A semiconductor device includes an isolation layer disposed in a semiconductor device to define an active region. A gate trench is disposed across the active region and extends to the isolation layer. An insulated gate electrode fills a portion of the gate trench and covers at least one sidewall of the active region. A portion of the gate electrode, that covers at least one sidewall of the active region, extends under a portion of the gate electrode that crosses the active region. An insulating pattern is disposed on the gate electrode.

1. Technical Field
The present disclosure relates to a semiconductor device and to a method of fabricating the same, and more particularly, to a semiconductor device having a buried gate electrode and to a method of fabricating the same.
2. Description of Related Art
Driven by an increased demand for highly integrated semiconductor devices, extensive research has been conducted into minimizing the areas of components such as, for example, transistors. With the downscaling of a transistor, the channel length and the channel width may also need to be decreased as well. However, a reduction in effective channel width may also lead to a drop in channel current, thereby lowering the current driving capability of the transistor. Also, a reduction in effective channel length may cause not only an increase in the channel current but may also lead to other difficulties, such as, for example, a short channel effect.
A recess-channel metal oxide semiconductor field effect transistor (MOSFET) has been proposed to overcome the short channel effect and downscale the transistor. The recess-channel MOSFET includes a recessed channel region and an insulated gate electrode. The insulated gate electrode is disposed on the recessed channel region. Thus, the recess-channel MOSFET can have a larger effective channel length than a planar MOSFET. In other words, the recess-channel MOSFET has an improved structure that diminishes difficulties caused by the short channel effect.
However, when the insulated gate electrode protrudes over a semiconductor substrate, the recess-channel MOSFET may preclude subsequent processes, such as, for example, the formation of a contact plug and a planarization process. Also, upper corners of the recessed channel region may cause the occurrence of leakage current due to a field crowding effect. Further, formation of the protruding gate electrode involves a very complicated patterning process.
In an attempt to overcome the above-mentioned difficulties, a semiconductor device having a buried word line was researched and is described in U.S. Pat. No. 6,770,535 B2, entitled "Semiconductor Integrated Circuit Device and Process for Manufacturing the Same", by Yamada et al.
According to Yamada et al., a trench is formed across a channel region and an isolation layer. A word line is formed to fill a portion of the trench. An insulating pattern is formed to fill the remaining portion of the trench. As a result, the word line is buried underneath a semiconductor substrate. The buried word line provides a relatively longer effective channel length.
However, the effective channel width of the semiconductor device described in U.S. Pat. No. 6,770,535 B2 is dependent upon the channel region and the buried word line. Thus, the semiconductor device having the buried word line has substantially the same effective channel width as a planar MOSFET. As a result, the semiconductor device having the buried word line may be inferior to the planar MOSFET in current driving capability. For examples lowering of current driving capability may make it difficult to elevate the integration density of the semiconductor device.
Furthermore, the recess-channel MOSFET may have certain structural difficulties compared to the planar MOSFET in terms of a body effect, for example, an increase in threshold voltage.
In conclusion, there is a need in the art for an improved transistor and fabrication technique that adopt a buried word line and diminish the difficulties caused by a body effect.

Semiconductor device having buried gate electrode and method of fabricating the same


Provided is a preventive, ameliorant or remedy for hypertension excellent in both blood pressure lowering action and blood pressure-rise suppressing action and having high safety.

Examples of a pharmaceutical used for treatment of hypertension include various neuroleptics acting on the neural-factor-related regulator system, ACE inhibitors acting on the heurohumoral-factor-related regulator system, AT receptor antagonists, Ca antagonists acting on the vascular-endothelium-derived-substance-related regulator system, and hypotensive diuretics acting on the body-fluid-regulator system in the kidney. These pharmaceuticals are mainly used in medical institutions for patients suffering from severe hypertension.
Under the present state, however, pharmaceuticals used as a measure against hypertension are a serious burden for patients because in spite of satisfactory effectiveness, their side effects are not a few.
In the case where hypertension is regarded as a life-style related disease, on the other hand, general therapies for improving the life style such as dietetic therapy, kinesitherapy and limitation of alcoholic intake or smoking are applied widely not only to the people having a high normal blood pressure including a mild case but also to patients suffering from severe hypertension. With a tendency to recognize the importance of general therapies, improvement of eating habits has received great attention. Since there exist a large number of foods having blood pressure lowering action, pressure reducing materials derived from foods have so far been briskly searched for and separation and identification of their effective ingredients have been carried out frequently.
Under such situations, there is an increasing demand for the development of a method for preventing, ameliorating or treating hypertension without depending on pharmaceuticals if possible. As such a method, dietetic therapy is particularly important, so that foods having blood pressure lowering effects or blood-pressure-rise inhibitory effects have briskly been searched for. Proposed is use of, as a hypotensor, the juice of an unripe fruit of apples, pears, peaches or like fruits belonging to the family Rosaceae which juice contains fruit polyphenol such as caffeic acid having angiotensin I converting enzyme (ACE) inhibiting action (Japanese Patent Application Laid-Open (Kokai) No. Hei 8-259453). It is also reported that a water extract of sugarcane root tuber contains a chlorogenic acid, which is a polyphenol, and it has ACE inhibitory action (Food Research Results Information, No. 9, 20–21(1997)).
Foods which are said to have pressure reducing effects or their effective ingredients, however, tend to be not always satisfactory in their effectiveness, intake frequency or taste upon intake and in addition, many of them do not start exhibition of blood pressure lowering effects soon after intake.
An object of the present invention is therefore to provide a preventive, alleviative or remedy for hypertension which is derived from plants or foods, has excellent safety, does not become a burden for patients when administered daily and orally, and has high antihypertensive action.

This patent is subject to a terminal disclaimer.

Preventive, alleviative or remedy for hypertension

Abstract: This preventive, ameliorant or remedy for hypertension comprises a coffee bean extract.


Disclosed are various embodiments for coordination of autonomous vehicles in a roadway. A roadway management system can generate lane configurations for a roadway or a portion of the roadway. The roadway management system can determine the direction of travel for lanes in a roadway and direct autonomous automobiles to enter the roadway in a particular lane.

Autonomous vehicles can facilitate efficient transportation networks. Reversible or reconfigurable lanes can also facilitate efficient traffic flow through roadways in a roadway network. Autonomous vehicles may not have information about reversible lanes when approaching a portion of a roadway that has reversible lanes. Additionally, an autonomous vehicle may be unaware of an optimal lane at which to enter a roadway that has reversible lanes.

Lane assignments for autonomous vehicles


A food additive composition in an all-in-one powder composition containing multiple vitamins, calcium citrate, minerals, herbs, beans, peas, corn, grains, flakes, berries, and cloves. The composition is prepared by forming a mixture of the ground beans, corn and peas with the grains, spices, herbs, and vitamins. The mixture is steamed and baked in an oven. At least three different compositions are formulated and with different degrees of spiciness. The nutritious and flavorful additive composition can be added to food being cooked or while eating out.

1. Field of the Invention
The present invention relates generally to food supplements. More specifically, the invention is a food additive, an all-in-one powder composition containing multiple vitamins, calcium citrate, minerals, herbs, beans, peas, grains, flakes, berries, and spices to add a delightful flavor to any food consumed and curbing one""s appetite.
2. Description of the Related Art
The related art of interest describes various food supplements, but none discloses the present invention. There is a need for a powdered food additive which supplies a variety of nutrients and flavors for enriching and flavoring one""s food, but also curbing one""s appetite to prevent overeating. The related art will be discussed in the order of perceived relevance to the present invention.
U.S. Pat. No. 4,710,387 issued on Dec. 1, 1987, to Dirk J. D. Uiterwaal et al. describes a nutritional supplement preparation for pregnant and breast-feeding women based on milk constituents and the process of preparation. The composition contains by weight 10-20% protein, 16-28% fat, 43-65% carbohydrates, at most 3.5% moisture, minerals, trace elements, and vitamins such as calcium, phosphorus, magnesium, copper, zinc, iodine, iron, vitamins A, B1, B6, C, D3, E, niacin, folic acid, and optionally flavoring and/or colorant. The composition is distinguishable for being tailored to supply nutrients to a pregnant or breast-feeding woman and requires large amounts of fat (linoleic acid) and carbohydrates (lactose, dextrins and sucrose).
U.S. Pat. No. 5,770,217 issued on Jun. 23, 1998, to Frank J. Kutilek, III et al. describes a dietary pilled supplement comprising herbs, herbal extracts, vitamins, minerals, and amino acids effective in modulating hematological toxicities, enhancing the immune system and maintaining appetite and weight. The supplement contains a large amount of crucifer extract (8-12 wt. %) and ascorbic acid or vitamin C (8-13 wt. %). The amino acids include glutathione, L-cysteine and L-methionine. The composition is distinguishable for requiring crucifer extract and amino acids in pill form.
U.S. Pat. No. 4,348,379 issued on Sep. 7, 1982, to Horst Kowalsky et al. describes a dietetic composition for natural digestion regulation comprising in parts by weight each of 50-150 of whole fleawort seeds, whole linseed, wheat bran, and lactose. A binding agent based on natural rubber and optionally, flavor and/or food color. The composition is distinguishable for requiring fleawort seeds and whole linseed.
U.S. Pat. No. 4,440,760 issued on Apr. 3, 1984, to Rex E. Newnham describes a food supplement for the relief of arthritic conditions comprising in parts by weight of 2-500 of sodium tetraborate, 150 each of the dried herbs Gauaiacum, Berberis and Harpagophytum, 1 ppm Rhus-tox and/or Bryonia, gum arabic as binder, starch as a disintegration aid, and magnesium stearate as a lubricating aid in tablet forming. The composition is distinguishable for requiring sodium tetraborate and several dried herbs not required in the present invention.
U.S. Pat. No. 5,332,579 issued on Jul. 26, 1994, to Anthony J. Umbdenstock describes a nutritional supplement for optimizing cellular health of recovering drug addicts, alcoholics, smokers, etc., comprising: 1,500-15,000 I.U. vitamin A; 5,000-45,000 I.U. Beta-carotene; 33-300 mg. vitamin B1; 50-1,000 mg. vitamin B6; 30-300 mcg. vitamin B12; 20-500 mg. niacin; 100-2,000 mg. niacinamide; 100 mg. vitamin C; 5-100 mg. magnesium; 10-100 mg. zinc; 50-1,000 mg. valerian root; at least two minerals selected from the group consisting of calcium, 20-500 mcg. chromium, copper, iron, 5-1,000 mg. manganese, and selenium; and at least four additional vitamins, herbs, and amino acids selected from the group consisting of 100-1,000 I.U. vitamin D3, 10-800 I.U. vitamin E, 5-100 mg. vitamin B2, 100-1,000 mcg. biotin, 50-500 mg. pantothenic acid, 70-900 mg. choline, 100-1,000 mg. inositol, 50-1,000 mg. glutamic acid, 50-1,000 mg. glutamine, and echinachea. The composition is distinguishable for omitting beans, peas, berries, and grains. U.S. Pat. No. 5,656,312 issued on Aug. 12, 1997, and U.S. Pat. No. 5,834,048 issued on Nov. 10, 1998, to Udo Erasmus et al. describes a daily dietary food supplement composition packaged in a sealed pouch for humans comprising at least by weight proportions, 71-73% flax seeds, 5% yeast, 6% rice and bran yeast, 2% liver, 2% alfalfa, 1% bone, 2% carrot, 2% apple, 0.07% kelp. 0.01% lecithin, 0.01% garlic, 0.02% taurine, 0.01% equiteum herb, and 0.01% carnitine. The composition must be prepared at a temperature below 100xc2x0 F. for less than 20 minutes and in the limited illumination of red light. The food composition is distinguishable for requiring liver, yeast, flax seeds, garlic, and taurine as well as limited heating and lighting conditions.
U.S. Pat. No. 5,925,377 issued on Jul. 20, 1999, to Teja D. Gerth et al. describes a dietary supplement composition combining amino acids, minerals, herbs, vitamins, diuretics, and digestive enzymes. For example, D,L-phenylalanine is combined with tyrosine, L-glutamine and St. John""s wort to act as an appetite depressant while L-carnitine is combined with chromium picolinate to work as fat directors to convert stored body fat into energy. The composition is distinguishable for requiring diuretics and digestive enzymes.
U.S. Pat. No. 5,976,579 issued on Nov. 2, 1999, and U.S. Pat. No. 6,143,332 issued on Nov. 7, 2000, to Linsey McLean describes a nutritional supplement for the prevention and treatment of excessive intestinal permeability comprising at least 50 wt. % nutritional buffers (calcium carbonate), amino acid chelates (selenium, copper, zinc, manganese, iodine, and chromium), minerals, vitamins (A, B-complex, D, and E), antioxidants, free radical scavengers, and intestinal tract-soothing herbs. The composition is distinguishable for requiring buffers, chelates, antioxidants, and free radical scavengers.
U.S. Pat. No. 6,238,672 B1 issued on May 29, 2001, to Jau-Fei Chen describes dietary supplements containing dehydrated cactus fruit juice and ginseng berry juice for food products, drinks, capsules, and tablets. The supplement is distinguishable for requiring cactus fruit juice and ginseng berry juice.
U.S. Pat. No. 6,264,995 issued on Jul. 24, 2001, to Thomas Newmark et al. describes a herbal composition for reducing inflammation in bones and joints comprising holy basil, tumeric, ginger, green tea, rosemary, huzhang, Chinese goldthread, barberry, oregano, and scutellariae baicalensis. The composition is distinguishable for its medicinal characteristics.
U.S. Pat. No. 6,274,189 B1 issued on Aug. 14, 2001, to Massoud Kazemzadeh describes a reduced-flatulence, legume-based snack foods which comprises saccharides depleted legumes (field bean, white pea bean, Tepary bean, Mung bean, lima bean, Broad-bean, chickpea, lentil beans, peanuts, buckwheat, and flax) grain-based ingredients (cereal grain, oil seed, oil seed flour, and mixtures thereof) , water, and processing aids (inorganic and organic compounds of calcium, potassium, sodium, and mixtures thereof) processed with a developed matrix having a high crunch texture and a low fat absorption when cooked. The compositions are distinguishable for requiring cooking.
German Patent Application No. DE 31 43 926 A1 published on May 11, 1983, for Kurt Jesselring et al. describes a dietetic composition containing bran and/or pectin, vitamins, minerals, customary auxiliaries and carriers, and an anti-thrombotically active fraction derived from Basidiomycetes such as Auricularia, Himeola auricula judae, Polyporus ovinus, Polyporus giganteus, and Sparassis crispa. The composition is distinguishable for requiring an antithrombotically active fraction.
German Patent Application No. DE 44 16 402 A1 published on Nov. 30, 1995, for Harro Carstens et al. describes an immunity improving food additive comprising ethanolic extra extracts of medicinal herbs (aloe), vegetable oils containing eugenol, and, optionally, conventional stabilizers and additives. The medicinal herb extracts have a detoxifying effect through the stomach and intestinal tract. The composition is distinguishable for requiring only herb extracts, vegetable oils and eugenol.
French Patent Application No. 2 737 849 published on Feb. 21, 1997, for Jean P. Curtay et al. describes an orally administered food supplement for adults over forty years of age comprising: (1) an excipient (gum arabic or starch); (2) mineral salts (calcium carbonate, magnesium carbonate, zinc citrate; (3) vitamins B1, B2, B6, B8, B9, B12, C, E, and PP; (4) beta-carotene, (5) borage oil (herb); (6) fish oil; and (7) methionine. The composition is distinguishable for requiring beta-carotene, borage oil and methionine.
German Patent Application No. DE 196 53 100 A1 published on Jul. 23, 1998, for Adolph Metz describes a lactose-containing magnetic capsule food supplement comprising: (1) ferromagnetic magnetite; (2) piezoelectric rock crystal (silica); (3) magnesite powder (magnesium carbonate); (4) ginseng root, taiga root, mistletoe, ginkgo biloba leaves, hawthorn flowers or leaves, horse chestnut leaves, milk thistle, balm mint leaves, St. John""s wort, speedwell, linden flowers, arnica flowers, lesser centaury (Erythraea centaurium), marigold flowers, yarrow (Achillea millefolium), red soapwort, and calamus root; and (5) vitamins A, C, E, aneurin, riboflavin, pyridoxine, B12, and Q10; reduced glutathione, glutamine, cysteine, methionine; (6) Ca-, Mg- and K-citrate; (7) E. Coli or Lactobacillus acidophilus; (8) heartwood of Thuaja plicata; (9) oak bark; (10) aspirin and/or willow bark; (11) zinc, selenium and manganese; and (12) lactose, starch and dextrose. The composition is distinguishable for requiring a vast variety of exotic herbs, vitamins, lactose, minerals, and a magnetic constituent.
W.I.P.O. Patent Application No. WO 98/00024 published on Jan. 8, 1998, and W.I.P.O. Patent Application No. WO 98/47376 published on Oct. 29, 1998, for Houn S. Hsia describes a diet supplement composition to increase the level of high density lipoprotein (HDL) and calcium ions, and to decrease the levels of free radicals and glucose in human blood plasma comprising; (1) anti-oxidants selenium, vitamins A, B, C, D, and E, and fruit or vegetable juice concentrates; (2) green barley composition; (3) tincture of ginkgo biloba extract; and (4) minerals. The composition is distinguishable for requiring minerals, ginkgo biloba, and fruit and vegetable juice concentrates.
German Patent Application No. DE 199 07 586 A1 published on Aug. 24, 2000, for Waldemar Braun et al. describes a daily nutritional composition comprising (a) a basic kit for constant circadian dosage combined with (b) an xe2x80x9cadd-onxe2x80x9d supplement used in time-dependent amounts. The basic kit contains specific amounts of various vitamins and minerals including beta-carotene, vitamins B1, B2, B6, B12, niacin, pantothenic acid, biotin, folic acid, phylloquinone, calcium, magnesium, manganese, zinc, iron, selenium, chromium, molybdenum, copper, and iodine. The xe2x80x9cadd-onxe2x80x9d composition contains apple vinegar powder, artichoke extract, carnitine, guarina, silica, creatine, lecithin, and taurine. The compositions are distinguishable for requiring minerals and the xe2x80x9cadd-onxe2x80x9d composition.
None of the above inventions and patents, taken either singularly or in combination, is seen to describe the instant invention of flavoring as claimed. Thus, a food additive composition solving the aforementioned problems is desired.
The present invention is a food enhancer which curbs one""s appetite while simultaneously adding nutritional value and flavor to the food to be eaten. The composition is in powder form that is versatile in application to any food. The food additive can be added to food being cooked, included in appetizers or sprinkled on any food while eating out. It consists of a variety of beans, grains, vitamins, herbs, and spices. Because the food enhancer is taken in powder form, absorption by the body is maximized and it is easier to swallow as opposed to tablets. This composition is intended to replace salt, pepper and other spices.
Accordingly, it is a principal object of the invention to provide a food supplement to replace salt, pepper and other spices in one""s diet.
It is another object of the invention to provide a food supplement in powder form.
It is a further object of the invention to provide a food supplement containing beans, grains, vitamins, herbs, and spices.
Still another object of the invention is to provide a food supplement which can be added to food being cooked or when dining out to add that extra flavor and nutrients.
It is an object of the invention to provide improved elements and arrangements thereof for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.


There are provided a seal fin, a seal structure, and a turbo machine that can achieve a high leak-suppressing effect and can reduce leak loss of the turbo machine. The disclosure suppresses leak of a fluid from a gap between a first structure being in a static state and a second structure rotating around an axis line and is formed on the first structure so as to extend toward the second structure while keeping a clearance between a tip face thereof on an extending direction and the second structure. The first structure and the second structure face each other in a radius direction with the gap inbetween. A plurality of hollows opening at a tip on the extending direction are arranged along a circumference direction in parallel with each other on a front face facing an upstream side of a flow direction of the fluid.

In a turbo machine such as a steam turbine, a gas turbine, or a turbo compressor, possible leak of an operation fluid such as steam from a gap between a stationary side and a rotating side causes a loss (leak loss) of the efficiency in the turbo machine. With the foregoing problem in view, a turbo machine uses a non-contact seal structure such as a labyrinth seal to avoid leak of an operation fluid.
Patent Literatures 1 and 2 disclose techniques related to a non-contact seal structure for a turbo machine. Hereinafter, description will now be made in relation to techniques disclosed in Patent Literatures 1 and 2. In the description, the reference signs used in Patent Literatures 1 and 2 are indicated in brackets.
Patent literature 1 discloses "a seal device that seals the space between a stationary body (11) and a rotating body (12) and that includes: a fin (13) protruding from the stationary body (11) toward the surface (12a) of the rotating body (12) and having a sharp tip; and a coarse face section (17) formed on the surface (12a) of the rotating body (12)" (see the front page, paragraph [0021], and FIGS. 1 and 2). According to Patent Literature 1, the coarse face section (17) disturbs flow surrounding the fin (13), so that the pressure loss of the fluid (14) is increased and an amount of the fluid (14) that leaks from the space between the fin (13) and the rotating body (12) can be reduced.
Patent Literature 2 discloses "a seal device including, in a labyrinth seal (28) that seals the space between the stationary body and the rotating body, a restriction ring (32) and a deflector means (36) arranged on a downstream of the restriction ring (32)" (see the front page, lines 15-30 in column 3, and FIGS. 1-5). The restriction ring (32) is formed so as to protrude from the platform (30) of the rotor assembly (10) toward the seal face (34) on the tip of the vane (24). The deflector means (36) is formed so as to protrude from the seal face (34) toward the platform (30) in contrast to the restriction ring (32).
According to Patent Literature 2, the operation fluid leaking from the first throttle opening (38) between the restriction ring (32) and the seal face (34) is deflected by the deflector means (36) and is therefore can be prevented from further leaking from the second throttle opening (40) between the deflector means (36) and the plat form (30).

Seal fin, seal structure, and turbo machine


Methods, apparatus, systems, computing devices, computing entities, and/or the like for programmatically generating multi-paradigm feature representations are provided. An example method may include generating a code dataset including a plurality of codes associated with a predictive entity; generating a plurality of semantic feature vectors based at least in part on code description metadata; generating a plurality of structural feature vectors based at least in part on code relation metadata; generating a plurality of multi-paradigm feature vectors based at least in part on the plurality of semantic feature vectors and the plurality of structural feature vectors; generating a prediction for the predictive entity by processing the plurality of multi-paradigm feature vectors using a prediction model; and performing one or more prediction-based actions based on the prediction.

Computer algorithms (for example, machine learning models and/or artificial intelligence programs) may be implemented to analyze trends and/or patterns in the data. For example, prediction models may analyze data related to medical claims for the purpose of identifying potential healthcare fraud, waste, abuse, error (FWAE), predicting disease progression, and/or the like.
Raw data may need to be transformed and/or converted to feature representations that are recognizable by and compatible with prediction models in order to be provided as input data. Applicant has identified many technical challenges, deficiencies and problems associated with transforming and/or converting raw data. For example, many techniques do not fully capture all the intrinsic properties of raw data, resulting in information loss during transformation/conversion and inaccurate outputs from the corresponding prediction models.

Method, apparatus and computer program product for generating multi-paradigm feature representations


An apparatus and method for removing an interference signal using a selective frequency phase converter are disclosed. The apparatus for removing an interference signal using a selective frequency phase converter includes: a first phase converter configured to convert a phase of a received RF signal to differentially output first and second signals having a phase difference of 180° from each other; a second phase converter configured to receive the first signal and selectively convert the phase of a particular frequency band; a third phase converter configured to receive the second signal and selectively convert the phase of a particular frequency band; a timing controller configured to correct a signal delay time between the output from the second phase converter and that of the third phase converter; and an adder configured to add an output from the second phase converter and an output from the third phase converter, wherein the second and third phase converters phase-convert the first and second signals such that the phases of the signals of the particular frequency bands do not have a phase difference of 180° from each other.

1. Field of the Invention
The present invention relates to an apparatus and method for removing interference signals using a selective frequency phase converter (or phase shifter) and, more particularly, to an apparatus for effectively removing interference signals by selectively phase-converting a signal of a particular frequency band by using simple hardware.
2. Description of the Related Art
An RF signal received in a wireline/wireless communication system includes signals from unnecessary frequency bands as well as signals from the necessary particular frequency band, and such undesired and unnecessary signals from other frequency bands are known as interference signals. Because most interference signals include signals generated by other systems, they have considerably powerful signal power strength, making the operation of electronic parts of a receiver system enter a saturated state, which can result in degradation of receiver performance. Thus, in order to ensure the stable operation of a receiver system, the strength of the interference signals must be attenuated to below a certain level in a front stage of a receiver. In addition, as an ideal communication system is supposed to only receive a signal of a particular required band, the removal of interference signals is closely connected with the performance of the communications system.
The related art method for removing interference signals includes a method of using a band pass filter, a method of using a notch filter, a feed-forward method, and various others.
The method of using a band pass filter allows a received signal to pass through a band pass filter having a pass band including a particular required frequency band. In this method, signal loss occurs to some extent even in the pass band, due to the non-ideal characteristics of the band pass filter, leading to an attenuation of even the signals of the particular required frequency band. In addition, in order to use the band pass filter, an external element must be mounted in the system, increasing the size of the system.
The method of using a notch filter allows a received signal to pass through a notch filter that removes signals of a certain range of frequency band. This method is effective for removing interference signals present in a narrow frequency band, but has difficulty in removing interference signals distributed across a wide frequency band.
The feed-forward method is where a received signal is first down-converted, such that its particular required frequency band is positioned at a baseband, namely, in the vicinity of DC, and allowed to pass through a high pass filter to remove a signal of particular required frequency band. The resultant signal's phase is then converted (i.e., shifted) by 180°, which is then up-converted so as to be added to the originally received signal, thus removing interference signals. This method is advantageous in that signal loss is minimal and interference signals across a wide frequency band can be effectively removed, however, the hardware configuration is complicated due to the fact that a down-converter and up-converter as well as a high pass filter must necessarily be used.

Apparatus and method for removing interference signal using selective frequency phase converter

Electronics and Telecommunications Research Institute


Spherical agglomerates of finely divided material such as inorganic oxides are prepared by admixing a slurry of finely divided material with a solution of a partially neutralised carboxylic acid.

The present invention relates to the production of free-flowing spheres of solid particulate materials using partially neutralised carboxylic acids.
In producing and processing finely divided solid materials in dry form, it is desirable that the particles be substantially uniform in shape and size and that they be free-flowing. Various finely divided materials are required to be substantially dispersed in polymeric or liquid media. In such dispersions, the term "primary particles" refers to the individual crystals and tightly held aggregates thereof "Agglomerates" are larger associations of the primary particles. Ideally, a dispersion consists mainly of primary particles and a minimum of loosely held aggregates consisting of co-adhering primary particles. In contrast, when finely divided materials are processed in dry solid form, the particles can be larger, but are preferably uniform in shape and size so that they are free-flowing.
Powders consisting of such finely divided materials generally exhibit poor flow properties and readily generate undesirable levels of dust. Powders which are coated with hydrophobic agents which assist pigment wetting and dispersion in polymer systems can exacerbate problems such as dustiness. Poor flow characteristics result in difficulties achieving accurate flow metering. Excessive dustiness can cause problems with respect to industrial hygiene. Free-flowing aggregates overcome these problems. A weakness of current methods of producing free-flowing powders is that the aggregates are difficult to de-aggregate to primary pigment particles, which limits their applications. A further weakness of some methods used to produce free-flowing powders is that significant quantities of binders, up to 20% by weight with respect to the particulate material, are required.
Some free-flowing plastic grade pigments or fillers are commercially available. Due to the role of pigments such as titanium dioxide as opacifying agents, the primary pigment particles must be sub-micron in size. Free-flowing plastic grade pigments or fillers are available such as Tioxide's TR36 or Bayer's R-FK21; however, both of these grades suffer from a difficulty to deaggregate and disperse, which limits their usefulness. The present invention substantially overcomes this weakness.
U.S. Pat. No. 4,375,989 discloses titanium dioxide pigments whose dispersibility is improved by coating with an organic coating and also an inorganic coating. Organic substances used for coating include large-molecule fatty acids and their salts. Suitable inorganic coatings are oxides and hydroxides of aluminium, zinc, titanium, zirconium and magnesium.
U.S. Pat. No. 4,186,028 discloses aqueous fluid suspensions of fillers or pigments containing dispersion aids which can include phosphonocarboxylic acids and/or salts thereof.
U.S. Pat. No. 4,563,221 discloses pigments comprising particulate titanium dioxide having an organic coating of isostearic acid, dodecyl benzene sulphonic acid and a cationic emulsifying agent of a fatty alkyl amine. The pigment particles are described as free of inorganic coatings, and after treatment do not require milling in a fluid energy mill.
U.S. Pat. No. 1,722,174 proposed the use of alkali metal and ammonium salts of fatty acids for rendering lithopone (a mixture of zinc sulfide and barium sulfate) organophilic.
U.S. Pat. No. 3,042,539 discloses the use of alkali metal and ammonium salts of fatty acids for treating zinc oxide to produce organophilic pigments of very fine particle size.
U.S. Pat. No. 4,255,375 discloses the treatment of aqueous dispersions of organic pigments with at least one organic acid (such as octanoic) which is liquid at temperatures below 100.degree. C., or a salt thereof, at a pH value at which the acid is water insoluble, maintaining the temperature above the melting point of the acid until the pigment has transferred into the organic phase, and then adding base to increase pH until the acid becomes water soluble. The amount of organic acid added to the pigment is greater than 10 weight percent of the resulting composition, based upon the disclosure of acid and salt as "from 0.1 to 4 parts . . . by weight per part of pigment." The pigment is recovered as spherical granules from 0.1 to 3mm in diameter.
U.S. Pat. No. 3,506,466 discloses titanium dioxide pigments, with or without inorganic coatings, which are treated with salts of water-soluble alkanolamines and oxycarboxylic acids and then milled in a fluid energy mill.
Hungarian Patent No 148,370 discloses organophilic oxide pigments prepared by adding an aqueous soap solution of an alkali metal or ammonium salt of a fatty acid (such as ammonium stearate) to an aqueous slurry of an oxide, such as titanium dioxide, then adding an acid such as HCl to adjust the pH to about 5.
U.S. Pat. No. 4,224,080 discloses inorganic oxide pigments (such as titanium dioxide) coated with alumina and treated with water soluble reaction products of excess di- or polybasic organic hydroxy acids with di- or polybasic alcohols.
British Patent No 909,220 discloses dry titanium dioxide pigments which are treated with water-soluble salts of organic (eg carboxylic) acids with tertiary amines. The treated pigments are said to disperse more easily in a vehicle and to exhibit a greater tendency to dry flow.
U.S. Pat. No. 4,786,369 discloses abrasive soap powders which can comprise titanium oxide particles coated with soaps formed by the reactions of organic acids with alkaline hydroxides or amines.
U.S. Pat. No. 4,923,518 discloses chemically inert pigmentary zinc oxide compositions prepared by wet treatment of chemically reactive zinc oxide base pigments which include the application of chemically inert organic or inorganic coatings. Such coatings can include water insoluble metallic soaps of a saturated or unsaturated monocarboxylic acid and/or various hydrous metal oxides. The pigment particles can be spherical or acicular in shape.
U.S. Pat. No. 4,277,288 discloses a process for producing a substantially dry, low dusting, free-flowing granular pigment composition by contacting a fluidised bed of pigment and a granulating assistant.
U.S. Pat. No. 5,215,583 discloses formation of granules from a suspension of one or more pigments wherein the suspension also contains 0.05 to 5% of a soluble salt, selected from alkali/alkaline earth metal chlorides, sulfates and phosphates.
U.S. Pat. No. 5,215,584 discloses a method for producing inorganic granules from a suspension of one or more inorganic pigmenting agents and a hydrolysed or poorly soluble compound of one or more ion types present per se as an essential constituent in one or more pigments.
U.S. Pat. No. 5,108,508 discloses a method for producing microgranules which are free-flowing and non-dust forming comprising providing an aqueous suspension of pigment which optionally contains from 0.1 to 0.9% by weight of binder and optionally contains from 0.1 to 2.0% by weight of silicone oil and spraying said suspension into a spray tower through a hollow cone nozzle. The binder is a sodium or ammonium polyacrylate, and the granules have a toroidal shape.
U.S. Pat. No. 5,634,970 discloses a granulating process comprising pretreating inorganic pigments by the addition of oils as binders and subjecting the pretreated pigment to a compacting stage to form flakes which are then broken down by rough grinding.
Many techniques have been developed for producing and processing such finely-divided materials, but in most cases they still lack uniformity as to size and, particularly shape, and hence are not as free-flowing as desired. Clearly there is room for improvement in this field.
Accordingly, an object of the present invention is to produce finely divided particulate materials such as pigments in which the particles are agglomerates substantially uniform in size and shape. Another object of the invention is to produce particles which are substantially free-flowing in bulk. A further object of the invention is to produce agglomerates of such finely divided materials which are substantially spherical in form. A further object of the invention is to produce free-flowing agglomerates which are sufficiently robust to survive manual handling whilst still being sufficiently soft to readily de-aggregate and disperse within the media into which the powder is to be incorporated.

Production of free flowing spheres using partially neutralized fatty acid


In a process for improving the adhesive strength of radiation-cured films of acrylate resins which comprise compounds having at least one amine group and at least one unsaturated acrylate group and, in particular, an amino-modified acrylate resin having a molecular weight Mn of at least 300, on substrates, the acrylate resins are admixed with amine-hardenable polyepoxides having an epoxide value of from 1 to 15 mol/kg such as polyglycidyl esters or polyglycidyl ethers. Preferred curable mixtures of amine-modified acrylate resins with polyepoxides have amine numbers of from 1 to 250 mg KOH/g and epoxide values of from 0.1 to 4 mol/kg. The mixtures applied as coating films to metal substrates or plastics substrates, in particular, are radiation-cured with, e.g., UV light and an at least partial amine hardening of the polyepoxide compounds in the mixture is conducted by thermal conditioning at, e.g., from 50 to 120xc2x0 C.

The invention relates to a process for improving the adhesion of radiation-curable acrylate resins comprising amino-functional acrylates on substrates by admixing and amine-hardening a polyepoxide compound.
Radiation-curable coating materials based on acrylate resins are known and are often used for coatings on substrates such as metals or polymer moldings. The polymerization shrinkage which occurs in the course of radiation curing of the coating film applied to the substrate has an adverse effect on the adhesion of the coating material to said substrate. It is known that the adhesion of the radiation-curable coating film may be improved by increasing the molecular weight of the film-forming resins, reducing their double bond density, or adding non-reactive polymers. This, however, leads to a sharp and unwanted increase in the viscosity of the coating materials. Without doubt there exists a need for radiation-curable coating materials which are based on acrylate resins and possess good adhesion to metal or plastics substrates.
We have found that the adhesion of radiation-curable coating materials based on acrylate resins as binders to substrates is improved if the coating materials comprise at least one compound having amine groups and unsaturated acrylate groups and also comprise a small amount of polyepoxide compounds and if the coating film applied to the substrate is cured with high-energy radiation and stored, or thermally conditioned, at a temperature of above 50xc2x0 C., in particular of from about 50 to 120xc2x0 C.
The present invention therefore provides a process for improving the adhesive strength of radiation-curable acrylate resins or mixtures thereof, comprising a compound containing at least one amine group and at least one radiation-curable unsaturated acrylate group, to substrates, which comprises admixing the acrylate resins with at least one polyepoxide compound having an epoxide value of from 1 to 15 mol/kg, curing the film of the resultant acrylate resin, applied to the substrate, using high-energy radiation, and conducting at least partial amine hardening of the polyepoxide compounds by treatment at a temperature of above 50xc2x0 C.
The acrylate resin mixture obtained by admixing the polyepoxide compound(s) is sometimes referred to below as the coating material or coating mixture.
It was surprising that the process not only led to improved adhesive strength between the substrate such as a metal sheet or polymer film and the cured coating film but also brought about a reduction in cracking in the coating films and a reduction in the yellowing of the coating materials. A further surprise was the good storage stability of the uncured mixtures in comparison to mixtures which comprise epoxy resins and low molecular mass aliphatic amines as hardeners.
Acrylate resins are understood to be known reaction products, in resin form, of (i) methacrylic acid and/or acrylic acid with (ii) at least dihydroxy polyesters, polyethers, polyurethanes or epoxy resins (which comprise at least two functional groups which react with (meth)acrylic acid), and also reaction products of (i) hydroxyalkyl (meth)acrylates with (ii) compounds containing isocyanate groups. Radiation-curable acrylate resins of this kind are customary in commerce and are described, for example, in P. K. T. Oldring, Chemistry and Technology of UV and EB Formulation for Coatings, Inks and Paints, Vol. II: Prepolymers and Reactive Diluents, J. Wiley and Sons, New York and Sita Technology Ltd., London 1997, and in H. Kittel, Lehrbuch der Lacke und Beschichtungen [Textbook of Paints and Coatings], Volume VII: Processing of Paints and Coating Materials, pp. 240-245 etc., Verlag W. A. Colomb, Berlin 1979. The acrylate resins, which are subdivided, in accordance with their preparation and the repeating structural units in the molecule chain, into polyester acrylates, polyether acrylates, urethane acrylates, epoxy acrylates and melamine acrylates, are, as what are known as radiation-curable prepolymers, of relatively low molecular mass, generally having an average molecular weight Mn of from 300 to 15,000 and preferably from 400 to 3000 g/mol, as determined by gel permeation chromatography (GPC) using polystyrene as the standard and tetrahydrofuran as the eluent. The resins contain generally from 0.1 to 1.0 and preferably from 0.1 to 0.5 mol of polymerizable Cxe2x80x94C double bonds per 100 g of prepolymer. Very suitable (meth)acrylate resins contain from 2 to 20, in particular from 2 to 10, and preferably from 2 to 6, methacryloyl and/or acryloyl groups in the molecule. Among the acrylate resins, particular suitability is possessed by those derived from polyfunctional aliphatic alcohols having no functional groups other than the hydroxyl groups, except for ether, ester, and urethane groups. Examples of alcohols are dihydric, trihydric and higher polyhydric alcohols such as propylene glycol, diethylene glycol, triethylene glycol, butanediol, hexanediol, neopentyl glycol, cyclohexanediol, glycerol, trimethylolpropane, ditrimethylolpropane, pentaerythritol, dipentaerythritol, and sorbitol. Compounds suitable for preparing polyester acrylates are primarily aliphatic polyester polyols. Polyester acrylates may be prepared in one or more stages from polyols, polycarboxylic acids, and (meth)acrylic acid. They are described, for example, in EP-A 279303. Alcohols suitable for preparing polyether acrylates are, in particular, alkoxylated, preferably ethoxylated and/or propoxylated, polyhydric alcohols, in which the degree of alkoxylation per hydroxyl group may be from 0 to 10.
In accordance with the process of the invention, the acrylate resins in the mixture comprise compounds having at least one amine group and at least one radiation-curable unsaturated acrylate group, especially amine-modified acrylate resins having a molecular weight Mn of at least 300 and preferably at least 400 g/mol. The mixtures may be of amino-free acrylate resins with compounds having at least one amine group and at least one radiation-curable unsaturated acrylate group, such as an amine-modified acrylate resin, although exclusively amine-modified acrylate resins may also be used with advantage as binders. By amine-modified acrylate resins are meant here acrylate resins which comprise Michael adducts of aliphatic amines with primary and/or secondary amino groups. These may be amine-modified polyether, polyester, epoxy and urethane acrylates, with polyether and polyester acrylates being preferred. Highly suitable acrylate resins are those in which from 0.5 to 60, and in particular from 0.5 to 30, mol % of the (methlacrylic groups are present in the form of Michael adducts of an amine having a primary and/or secondary amino group. The preparation of amine-modified acrylate resins is described, for example, in Patent Applications DE-A 2346 424, DE-A 4007 146, EP-A 211 978, EP-A 280 222 and EP-A 731 121. Amine-modified acrylate resins particularly suitable for the process of the invention are those which have an amine number of from 5 to 450 and preferably from 20 to 250 mg KOH/g. The mixture of the coating components should contain an amine number of from 5 to 250, in particular from 5 to 100, and preferably from 20 to 50 mg KOH/g. Amine synergists based on multifunctional monomers may also be used in some cases.
In addition to the compound having amine groups, the coating mixtures of the invention comprise at least one amine-hardenable polyepoxide compound having an epoxide value of 1-15 and especially 3-8 mol/kg. Preference is given to aliphatic polyepoxides and also aliphatic or aromatic glycidyl ethers and glycidyl esters having at least 2 glycidyl groups. Highly suitable polyepoxides are aliphatic glycidyl ethers such as pentaerythritol triglycidyl ether, trimethylolpropane triglycidyl ether, glycerol triglycidyl ether, and neopentyl glycol diglycidyl ether. The epoxide groups of the polyepoxide compounds may also have been partially reacted with (meth)acrylic acid, subject to the proviso that two intact epoxide groups remain in the molecule. The molecular weights of suitable polyepoxide compounds are generally below 2000 and preferably below 1100 g/mol. The amount of the epoxide compounds in the mixture is guided by the epoxide value thereof and by the amount of the other constituents in the mixture; the acrylate resin mixture should have an epoxide value of from 0.1 to 4, in particular from 0.1 to 2, and preferably from 0.1 to 1, mol/kg.
For the purpose in particular of adjusting the viscosity or influencing the hardness of the coating films, the acrylate resin mixtures used in accordance with the invention may further comprise what are known as reactive diluents, i.e., radiation-curable monomers having in particular 1-4 Cxe2x80x94C double bonds. Appropriate monomers and the criteria for their selection are described, for example, in the book cited above in connection with the radiation-curable acrylate resins, by P. K. T. Oldring, Vol. II, Chapter III, pp. 261-325. Customary additives, furthermore, may also be added to the acrylate resin mixtures, such as matting agents, fillers, pigments, leveling assistants, etc. The amount of these customary additives is generally from 0.01 to 20 and preferably from 0.05 to about 10% by weight of the total amount of the mixture.
The acrylate resin mixtures may be applied conventionally to substrates such as metals or plastics, examples being polyethylene, polypropylene, polyurethanes etc., such as by knife coating, spraying, flow coating, or rolling. Layers of the acrylate resin mixtures can be applied to a substrate.
The radiation curing of the coating films can be carried out with the aid of high-energy radiation, such as UV rays, electron beams, or gamma rays. Preference is given to curing with UV light. In this case it is necessary to admix to the mixtures at least one photoinitiator in an amount of from 0.05 to 20 and preferably from 0.05 to 5% by weight, based on the total amount of the acrylate resin mixture. In this respect, reference may be made to the extensive literature, for example, to P. K. T. Oldring, Chemistry and Technology of UV and EB Formulation for Coatings, Inks and Paints, SITA Technology, London 1991, Vol. III: Photoinitiators for Free Radical and Cationic Polymerisation. Examples of photoinitiators that may be mentioned include benzophenone, alkylbenzophenones, halogenated benzophenones, Michler""s ketone, anthrone, anthraquinone and its derivatives, benzoin and its derivatives, and also acylphosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide. The reactivity in UV polymerization may be increased in a conventional manner by adding tertiary amines such as triethylamine, triethanolamine, or amine synergists (e.g., Laromer(copyright) LR 8956). Radiation curing with UV light is suitably conducted using artificial emitters whose emission lies within the range of 2500-5000, preferably 2500-4000, angstroms. Suitable emitters are mercury vapor lamps, xenon lamps and tungsten lamps, with preference being given to the use of high-pressure mercury emitters. Radiation curing gives a scratch-resistant coating film.
For thermal curing or partial curing of the polyepoxide-amine system, the irradiated coating film is treated (thermally conditioned) at temperatures of above 50xc2x0 C., in particular from 50 to 120xc2x0 C., and preferably from 60 to 120xc2x0 C. The temperature and duration of thermal conditioning are codetermined by the specific epoxy/amine system used and may easily be optimized in preliminary experiments. In general, thermal conditioning is carried out for from about 5 to 240 minutes, often longer. It has been found that the curing reaction initiated by the thermal conditioning often continues for a relatively long time, even if the coating has been cooled to room temperature in the meantime, thereby leading to a further improvement in the adhesive strength.
The resultant acrylate resin films have the surprising, advantageous properties indicated above. They are therefore particularly suitable for producing coatings on metal and plastic.
The examples and comparative experiments below are intended to illustrate, but not restrict, the invention.
Unless specified otherwise, all parts and percentages are by weight.
The epoxide value, or the epoxide equivalent weight, was determined in accordance with DIN 53188 by titrating a solution of resin in a dichloromethane-acetic acid mixture, with the addition of tetra-n-butylammoniumiodide and crystal violet as indicator, with 0.1 N perchloric acid up to the point of color change from blue to yellowish green. The epoxide value indicates the number of moles of epoxide groups present in 100 g of an epoxy resin. The following relation exists: epoxide value=100/epoxide equivalent weight.
The amine number indicates the number of mg of KOH that are equivalent to 1 g of the substance. It is determined by dissolving 1-2 g of the epoxy resin sample in 50 ml of acetic acid, adding crystal violet solution as indicator, and titrating with 0.1 N perchloric acid in acetic acid until the point of color change of the indicator from blue to yellowish green.
As a measure of the flexibility, the measurement was made in accordance with DIN 56156 of the Erichsen indentation (EI), in mm, both before and during thermal conditioning, with high values denoting high flexibility.
In order to test the adhesion, the cross-cut value (GT) was determined in accordance with ISO 2409 (DIN 53151), both with and without Tesa film tearoff (mT), and before and during thermal conditioning.
Additionally, in Table 3, the adhesive strength in N/mm2 was measured using the Twistometer torsion measuring instrument on a coating applied at 25 g/m2 to a deep-drawn metal panel. The method is described in Farbe und Lack, Vol. 80, 10/1974 and also in the BASF datasheet xe2x80x9cBestimmung der Haftfestigkeitxe2x80x9d [Determination of Adhesive Strength] PM/ED 038d (Jan. 1999). By continuous rotation of a shaft, the Twistometer raises the torque on pre-prepared adhesive plugs up to the fracture load; when this load is reached, a pointer remains fixed in position and permits the adhesive strength to be read off directly in N/mm2 on a scale on the instrument.
The yellowing was determined using a Lange Colorpen spectrophotometer (400-700 nm; 20 n) in analogy to DIN 6167, ISO 7724/1-3 and ASTM D 1925-70, and is reported as the b value.
The viscosity (mPa.s) was determined in accordance with DIN EN ISO 3217.
As a measure of the reactivity, the belt speed is reported at which coating film applications of 50 g/m2 can be moved under an undoped high-pressure mercury lamp (output 120 W/cm lamp length; distance of lamp from substrate: 12 cm) in order to give a coating which resists scratching with the fingernail.


A pulse width modulation control unit multiplies a value of a user side setting signal by a value of a dimming signal to obtain a pulse width modulation output current control signal. The pulse width modulation control unit sends the pulse width modulation output current control signal to a light emitting diode driving unit. The light emitting diode driving unit multiplies a value of the pulse width modulation output current control signal by a value of a maximum output current of the light emitting diode driving unit to obtain a light emitting diode pulse width modulation driving current. The light emitting diode driving unit drives a light emitting diode by the light emitting diode pulse width modulation driving current.

1. Field of the Invention
The present invention relates to a light emitting diode driving apparatus and a method for outputting current of the light emitting diode driving apparatus, and especially relates to a light emitting diode driving apparatus with variable output current and method for the same.
2. Description of the Related Art
Comparing to incandescent light sources, light emitting diodes have a lot of advantages, including lower energy consumption, longer life, improved physical endurance, smaller size and faster switching speed. Therefore, light emitting diodes are used widely to replace fluorescent lamps or tungsten lamps.
A light emitting diode driving apparatus is used to drive light emitting diodes. However, the disadvantage of the light emitting diode driving apparatus is that the output current of the light emitting diode driving apparatus is not changed easily. Generally speaking, the hardware of the light emitting diode driving apparatus has to be modified in order to change the output current of the light emitting diode driving apparatus.

Light emitting diode driving apparatus with variable output current and method for the same


The present invention relates to ear-of-rice-shaped copper particles. The technical gist thereof is a method of manufacturing ear-of-rice-shaped copper particles, ear-of-rice-shaped copper particles manufactured thereby, and a conductive paste using the same. The method includes a first step of preparing a copper precursor solution, a second step of adjusting the pH of the copper precursor solution, a third step of adding a zinc powder to the pH-adjusted copper precursor solution, a fourth step of synthesizing the ear-of-rice-shaped copper particles by stirring the copper precursor solution, to which the zinc powder is added, for a predetermined time, and a fifth step of separating, washing, and then drying the synthesized ear-of-rice-shaped copper particles.

In general, a conductive paste is manufactured by mixing a resin formulation, including a binder, a solvent, and a curing agent mixed therein, with a conductive filler. The conductive paste is widely used to form electrodes or circuits of various electric and electronic parts, or is widely used as bonding materials of devices and EMI shielding materials.
Examples of conductive filler typically used in the conductive paste include gold, silver, platinum, palladium, and copper, having high electrical conductivity. Gold, silver, platinum, and palladium have merits in that corrosion resistance is high and electricity is capable of easily flowing therethrough, but have a drawback in that they are very expensive. Copper has merits in that it is inexpensive and excellent in electrical conductivity. However, the surface of copper is easily oxidized due to the low corrosion resistance thereof, thus reducing the electrical conductivity thereof, which makes copper unsuitable for use as a conductive material.
In order to overcome this drawback of copper, the particle surface of copper may be coated with silver, although the manufacturing cost is increased.
Therefore, currently, most conductive pastes include silver, which has high electrical conductivity and which is relatively easily obtainable, as a conductive filler.
In order to reduce the high price of silver when using silver as the conductive filler, an attempt has been made to modify the shape of the silver particle so as to thus improve the electrical conductivity of the conductive paste while minimizing the amount of silver used therein.
FIG. 1 shows electrical conductivity measured depending on an addition amount when various types of silver particles are used as a conductive filler for a conductive paste. Electrical contact distribution is relatively increased when in the form of flakes rather than in the form of spherical silver particles and in the form of silver particles having many branches rather than in the form of flakes, and thus a similar electric conductivity is capable of being obtained with a small amount of addition thereof.
In particular, studies on the manufacture and application of conductive fillers in the form of dendrimer have been actively pursued as studies on conductive fillers having many branches.
It is reported that such a dendrimer-type conductive filler has electrical conductivity similar to that of a conventional flake-type filler even when using only about 50% of the addition amount in the case of a conventional flake-type filler (Nature Communication, 2015).
However, this result is obtained only when mixing of the filler and the resin formulation is performed under ideal conditions, and it is very difficult to effectively mix the dendrimer-type conductive filler with the resin formulation using a typical mixing method in the practical situation.
In particular, when the conductive filler is a dendrimer type, the surface area ratio thereof is greatly increased as the number and the length of branches are increased and the size of the manufactured particle is reduced, so that it becomes more difficult to perform uniform mixing while the resin formulation penetrates between the branches without local failures. Therefore, it is necessary to change the shape of the typical dendrimer-type filler to a somewhat integrated and simple shape in order to ensure effective mixing in an actual mixing process for paste-making.
To date, the development and study for dendrimer-type conductive filler materials has been conducted mainly using silver. However, in consideration of the characteristics of copper, which is as cheap as about 1/60 of the cost of silver and which has electrical conductivity similar to that of silver, the material of the dendrimer-type conductive filler is ultimately expected to be copper. Meanwhile, a surface treatment method using silver coating can be applied to eliminate the surface oxidation problem of the copper material.
A commonly known method of manufacturing dendrimer-type copper is to use a zinc or aluminum foil so that a copper dendrimer is generated and grows on the surface of the aluminum or zinc foil using a galvanic displacement reaction between zinc or aluminum and copper ions. Alternatively, an electrolytic application process using the above-described foils as a cathode material is used.
FIG. 2 shows an example of a conventional method of manufacturing a copper dendrimer. As shown in the drawing, an aluminum foil is immersed in an electrolytic solution containing copper ions so that the copper dendrimer grows using a galvanic displacement reaction. Electrons supplied using an oxidation reaction of aluminum are absorbed by copper ions in a solution, thus reducing copper.
However, this manufacturing method is known to be a high-cost process, in which somewhat complicated equipment is used and in which productivity is very low due to the heating process, which requires that a maximum temperature of about 120° C. be maintained for a maximum of 18 hours during a particle synthesis process, and a long synthesis time.
Further, the growth method on the foil faces an obstacle to mass production related to immersion of a large number of foils.
Further, the electrolytic process using the foils as the cathode material is widely used in order to increase a dendrimer synthesis rate, but this manufacturing method is fundamentally different from the process provided by the present invention in that it requires electricity to be applied.
Moreover, the manufacturing method using electrolysis has limitations such as the use of somewhat complicated equipment and the requirement to immerse a large number of foils for mass production.

Method for preparing rice ear-shaped copper particles, rice ear-shaped copper particles prepared thereby, and conductive paste using same


A method for producing a semiconductor device of the present invention includes forming a surface electrode on a semiconductor element, forming a solder layer by plating on one principal surface of the surface electrode, mounting the semiconductor element on the sub-mount so that the solder layer contacts a principal surface of the sub-mount, and bonding the sub-mount and the semiconductor element to each other via the solder layer.

1. Field of the Invention
The present invention relates to a semiconductor device and a method for producing the same. In particular, the present invention relates to a semiconductor laser element device including a semiconductor laser element mounted on a sub-mount, and a method for producing the semiconductor laser element device.
2. Description of the Related Art
An optical semiconductor element (in particular, a semiconductor laser) is being put into a practical use in the fields of optical information processing and optical communication. In both the fields, there is a demand for an increase in power of a laser. However, if the power is increased, there is a problem that reliability is decreased due to heat generated by an element and the like. This makes it important to develop an element configuration and a production process capable of keeping high reliability.
For example, in order to enhance heat radiation of a semiconductor laser element, a configuration is well known in which a base to be a heat sink made of a material having a high heat conductivity, and a sub-mount made of a material having a thermal expansion coefficient close to that of the laser element are stacked successively to be bonded to each other (e.g., see JP56(1981)-27988A and JP63(1988)-233591A).
FIG. 11 is a side cross-sectional view showing a configuration of a conventional semiconductor laser device. As shown in FIG. 11, the conventional semiconductor laser device has a configuration in which a semiconductor laser element 101, a sub-mount 102, and a base 103 are stacked. The semiconductor laser element 101 has a semiconductor layered body 131, a reverse-surface electrode 107, and a surface electrode 106. The surface electrode 106 is a pattern electrode composed of a plurality of patterned layers and is formed on one surface of the semiconductor layered body 131 in which an active layer 111 is formed. The reverse-surface electrode 107 composed of a plurality of layers is formed on the other surface of the semiconductor layered body 131. In FIG. 11, a light-emission point 112 of the semiconductor laser element is shown.
Furthermore, the sub-mount 102 includes an electrical insulating material 132, a surface electrode 108, a solder layer 104, a reverse-surface electrode 109, and a solder layer 105. On one surface of the electrical insulating material 132, the surface electrode 108 composed of a plurality of layers and the solder layer 104 are formed in this order. On the other surface of the electrical insulating material 132, the reverse-surface electrode 109 composed of a plurality of layers and the solder layer 105 are formed in this order.
Furthermore, the base 103 has a radiator 133 and an Au-plating layer 110. The Au-plating layer 110 is formed on the surface of the radiator 133.
Referring to FIG. 9, the semiconductor laser element 101 and the sub-mount 102 are bonded to each other by melting of the solder layer 104 therebetween. The sub-mount 102 and the base 103 are bonded to each other by melting of the solder layer 105 therebetween. Consequently, the semiconductor laser device shown in FIG. 11 is formed.
In the case where the driving current of the conventional semiconductor laser element 101 is in a wide current range of, for example, tens of mA to hundreds of mA, the amount of heat generation is increased. Therefore, a metallic radiator made of Cu or the like covered with a metal film 110 or the like in which Au-plating is formed on Ni-plating is used. Furthermore, the sub-mount 102 is made of a material having a thermal expansion coefficient close to that of the semiconductor laser element 101 in view of the connection process such as melting and bonding of the solder layers 104, 105, and the influence of heat generation during an operation of the semiconductor laser device.
Examples of the material for the solder layer 104 generally include an alloy of Au and Sn (hereinafter, referred to as an "AuSn alloy"), an alloy of Ag and Sn (hereinafter, referred to as an "AgSn alloy"), PbSn, AuSi, AuGe, AuZe, InSb, and the like. In particular, the AuSn alloy is used often in the semiconductor laser device due to its excellent corrosion resistance, high-temperature strength, and thermal shock resistance, and its small specific resistance.
In particular, the AuSn alloy and the AgSn alloy exhibit the effect of bonding at a low temperature due to a low melting point. For example, the melting point of Au is 1063° C.; however, by mixing Sn with Au, the melting point of Au is remarkably decreased, and in an eutectic composition of Au (80 wt %)-Sn (20 wt %), the melting point of Au is decreased to an eutectic point of 278° C. When the content of Sn is equal to or more than 20 wt %, the melting point of Au tends to increase gradually.
The melting point of Ag also is remarkably decreased by being mixed with Sn, and in an eutectic composition of Ag (3.5 wt %)-Sn (96.5 wt %), the melting point of Ag is decreased to an eutectic point of 221° C. Thus, the AgSn alloy enables mounting at a temperature lower than that of the AuSn alloy. When the content of Sn is equal to or more than 96.5 wt %, the melting point of Ag tends to increase gradually.
In mounting of the semiconductor laser element 101, bonding at a lower temperature is required for the following reason. Hereinafter, the case where the AuSn alloy is used as a material for a plating layer will be described. The surface electrode 106 provided on the semiconductor laser element 101 and the surface electrode 108 provided on the surface of the sub-mount 102 are made of a plating layer whose surface mainly contains Au. When the surface electrodes 106 and 108 are connected by heating via the solder layer 104, the AuSn alloy contained the solder layer 104 and Au contained in the electrodes 106 and 108 are alloyed to be integrated, whereby the surface electrodes 106 and 108 are bonded to each other via the solder layer 104. When the temperature is decreased to room temperature after connecting the surface electrodes 106 and 108, stress accumulates in the semiconductor laser element 101 due to a change in size of both materials caused by the difference in thermal expansion coefficient between the semiconductor laser element 101 and the sub-mount 102. This stress strains the semiconductor laser element 101, which greatly degrades the reliability of the semiconductor laser element 101.
Therefore, as the material for the sub-mount 102, SiC, AlN, diamond, Mo, or the like having physical property values (e.g., a thermal expansion coefficient, Young's modulus, etc.) close to those of the material for the semiconductor laser element 101 is selected. Furthermore, in order to reduce thermal stress, bonding at a lower temperature is required, and a solder material having a low melting point is selected for the solder layer 104.
In connection between the solder layer 104 made of an AuSn alloy and the surface electrodes 106 and 108, in the case where the content of Sn with respect to the total amount of Au of the alloy formed by the connection is an eutectic composition of Au(80 wt %)-Sn(20 wt %), bonding at a lowest melting point is made possible. However, in the case where a shift from the eutectic composition occurs, the melting point is increased. Thus, when the bonding temperature is set in accordance with the lowest melting point, the AuSn alloy of the solder layers 104 and 105 is not melted, or sufficient bonding strength cannot be obtained even if it is melted. When the bonding temperature is increased so as to avoid this, thermal stress is increased and causes strain. Because of this, it is important to control the content of Sn with respect to the total amount of Au in the surface electrodes 106, 108 and the solder layer 104.
Hereinafter, a method for forming the solder layer 104 of the AuSn alloy will be described. A first forming method is based on vapor deposition. The first forming method includes a method for stacking an Au layer and a Sn layer alternately to a desired thickness, using Au and Sn as respective vapor deposition sources (e.g., see JP6(1994)-69608A), and a method for forming an AuSn layer to a desired thickness, using an AuSn alloy that has been controlled for a composition as a vapor deposition source (e.g., see JP8(1996)-181392A). According to these methods, the thicknesses of the Au layer and the Sn layer, and the compositions thereof can be controlled by the thickness precision enabled by vapor deposition.
However, in order to obtain stable bonding strength, the thickness of the solder layer 104 desirably is 1 μm or more. In order to obtain the desired thickness, the film-formation time is prolonged, and the amount of a vapor deposition material is increased, which leads to an increase in cost.
A second method is to form an Au layer and a Sn layer by plating. According to this method, an Au-plating layer and a Sn-plating layer are stacked successively, and then, the stack is heated to form the solder layer 104 of an AuSn alloy. Alternatively, an Au-plating layer is formed on one opposed surface between the semiconductor laser element 101 and the sub-mount 102 to be bonded, and a Sn-plating layer is formed on the other opposed surface therebetween; they are heated under the condition that they are in contact, whereby the semiconductor laser element 101 is bonded to the sub-mount 102 (e.g., see JP11(1999)-204884A). According to this method, a thick layer can be obtained in a short period of time. Therefore, the solder layer 104 can be produced at a cost lower than that of the method using vapor deposition.
Next, mounting of the semiconductor laser element 101 on the sub-mount 102 will be described.
Generally, the semiconductor laser element 101 is mounted on the sub-mount 102 by a Junction-down (hereinafter, referred to as "J-down") method in most cases. According to the J-down method, the surface electrode 106 side of the semiconductor laser element 101 is bonded to the sub-mount 102. In the semiconductor laser element 101, the active layer 111 is formed on a side dose to the surface electrode 106. According to the J-down method, the semiconductor laser element 101 is bonded to the sub-mount 102 in such a manner that the surface electrode 106 on a side close to the active layer 111 generating heat is positioned dose to the base 103 that is a radiator. This allows the heat generated by the active layer 111 to diffuse to the sub-mount 102 smoothly. Therefore, the heat radiation of the semiconductor laser device can be enhanced.
However, in the case of the J-down method, the interval between the active layer 111 including the light-emission point 112 and the sub-mount 102 is several μm. Therefore, the solder layer 104 melted in the course of connection may come around the side wall portion of the semiconductor laser element 101 to cause a short-circuit defect, and may cover the light-emission point 112 to block laser light.
Therefore, as shown in FIG. 9, in most cases, the area for forming the solder layer 104 is patterned so as to be smaller than the contour of the semiconductor laser element 101. However, even with such a configuration, when a positional shift occurs in the course of arranging the semiconductor laser element 101 on the sub-mount 102, the solder material for the solder layer 104 may come around the side wall surface of the semiconductor laser device 101.
FIG. 10 shows each component before bonding for another conventional semiconductor laser device. FIG. 10 is different from FIG. 9 in that the solder layer 104 is not formed on the surface electrode 108 of the sub-mount 102, but is formed on the surface electrode 106 of the semiconductor laser element 101.
As shown in FIG. 10, in the case where the solder layer 104 is formed on the semiconductor laser element 101 side, even when a positional shift occurs in the course of mounting, the solder material for the solder layer 104 is unlikely to come around the side wall surface of the semiconductor laser element 101. Furthermore, in the case of using a two-wavelength laser element, a GaN laser element, or the like as the semiconductor laser element 101, the surface electrode 106 is composed of two or more pattern electrodes having the same thickness, and their electrode interval is small (i.e., about 100 μm). However, even in such a case, the solder layer 104 does not spread more than necessary, so that a short-circuit defect caused by the interval of the pattern electrodes can be prevented.
Furthermore, the advantages in the case where the solder layer 104 is formed on the semiconductor laser element 101 side will be described with reference to FIGS. 12A to 12C and FIGS. 13A to 13D. FIGS. 12A to 12C are views respectively illustrating an example of a mounting process for a semiconductor laser element in the case where a solder layer is formed on a sub-mount side.
First, as shown in FIG. 12A, the sub-mount 102 is held on a needle-shaped adsorbing collet 129, and placed at a predetermined position on the base 103. Next, as shown in FIG. 12B, the semiconductor laser element 101 is held by another adsorbing collet 130, and placed at a predetermined position on the sub-mount 102. Next, as shown in FIG. 12C, the resultant stack is heated to raise the temperature to melting points of the solder layers 104 and 105. Consequently, the solder layers 104 and 105 are melted simultaneously, and the base 103 and the sub-mount 102, and the semiconductor laser element 101 are bonded to each other simultaneously.
FIGS. 13A to 13D are views respectively illustrating an example of a mounting process for a semiconductor laser element in the case where a solder layer is formed on the semiconductor laser element side. First, as shown in FIG. 13A, the sub-mount 102 is held by the needle-shaped adsorbing collet 129, and placed at a predetermined position on the base 103. Then, the resultant stack is heated as shown in FIG. 13B to raise the temperature to the melting point of the solder layer 105, whereby the solder layer 105 is melted, and the base 103 is bonded to the sub-mount 102. Next, as shown in FIG. 13C, the semiconductor laser element 101 is held by another adsorbing collet 130, and placed at a predetermined position on the sub-mount 102. Next, as shown in FIG. 13D, the resultant stack is heated to raise the temperature to the melting point of the solder layer 104. Consequently, the solder layer 104 is melted, whereby the sub-mount 102 and the semiconductor laser device 101 are bonded to each other. It also may be possible for the sub-mount 102 to be bonded to the semiconductor laser element 101, and the resultant stack then bonded to the base 103 to produce a semiconductor laser device.
In such a production process, when the temperature is raised to the melting point of the solder layer 104 in bonding between the semiconductor laser element 101 and the sub-mount 102, in most cases, the stack is heated under the condition of being supplied with a load of about 10 g by the adsorbing collet 129 or 130 so that the semiconductor laser element 101 and the sub-mount 102 are not shifted from predetermined positions.
According to the method shown in FIGS. 13A to 13D, the steps shown in FIGS. 13A and 13B, and the steps shown in FIGS. 13C and 13D can be performed simultaneously at different positions. In this case, compared with the method shown in FIGS. 12A to 12C, there is an advantage of a high production efficiency. Furthermore, immediately after the sub-mount 102 and the semiconductor laser element 101 are placed at respective predetermined positions, they are bonded to each other, so that there also is an advantage of a high positional precision.
On the other hand, in the case where the solder layer 104 is formed on the sub-mount 102 side as shown in FIG. 12A, when the semiconductor laser element 101 is bonded to the sub-mount 102 after the base 103 is bonded to the sub-mount 102, there is the following problem. The surface of the solder layer 104 on the sub-mount 102 is placed at a predetermined position on the base 103 while being held by the adsorbing collet 129. Furthermore, the resultant stack is heated in that state. Therefore, the solder layer 104 also is melted at the same time as the melting of the solder layer 105, and a mark of the adsorbing collet 129 is formed on the surface of the solder layer 104 to generate level difference. Furthermore, there is a problem that a solder material adheres to the end of the adsorbing collet 129, and the like. When the solder layer 104 is melted in the course of bonding between the base 103 and the sub-mount 102, Au in the surface electrode 108 diffuses to increase the melting point thereof and the surface electrode 108 may be oxidized. Therefore, the temperature required thereafter for bonding the semiconductor laser element 101 to the sub-mount 102 via the solder layer 104 becomes high.
In order to solve these problems, the following is proposed: solder materials having different melting points are used for the solder layers 104 and 105, and the composition ratio of the same solder material is varied (e.g., JP11(1999)-214791A and JP9(1997)-172224A). According to these methods, along with an increase in steps, there is a possibility that the cost of the sub-mount 102 may be increased, and the bonding temperature and solder composition may be varied.
On the other hand, in the case where the solder layer 104 is formed on the semiconductor laser element 101 side as in the method shown in FIGS. 13A to 13D, the solder layer 104 is not formed on the opposed sub-mount 102 surface. Therefore, even if the sub-mount 102 is adsorbed and held by the adsorbing collet 129, and heating is performed while a load is applied, the mark of the adsorbing collet is not formed on the solder layer 104, and the solder layer 104 does not adhere to the adsorbing collet 129. However, in the case where the semiconductor laser element 101 with the solder layer 104 formed thereon is mounted on the sub-mount 102, the following problem arises. For example, as disclosed in JP11(1999)-204884A, when the solder layer 104 made of an AuSn alloy or the like is formed by plating, a thick film is obtained in a shorter period of time, compared with the vapor deposition method. However, the AuSn alloy layer or the like is formed after previously performing heat treatment, so that the number of steps is increased. Furthermore, since each layer is thick, there is a problem that the composition after alloying is not uniform in a layer, and stress is increased due to the variation in a melting point, the variation in a composition, and the segregation of Sn. Furthermore, JP11(1999)-204884A proposes a method for forming a paired layer including a thin Au-plating layer and a thin Sn-plating layer repeatedly, and controlling the total thickness of the Sn-plating and Au-plating. However, according to this method, the operation time is prolonged in the same way as in the case of vapor deposition.
Furthermore, as described with reference to FIG. 10, since the solder layer 104 is formed on the semiconductor laser element 101 side, there are advantages that a solder material can be prevented from coming around the side wall surface of the semiconductor laser element 101, a mounting method with a high production efficiency is applicable, and the like, as described above. On the other hand, there is a problem in cleavage processing.
Cleavage processing refers to an operation in which, when the semiconductor laser element 101 is produced, a plurality of semiconductor laser elements 101 are formed as a single unit, and then, the unit is divided into individual semiconductor laser elements 101. Hereinafter, the cleavage processing and problems caused therein will be described with reference to the drawings. FIGS. 14A to 14C are views respectively illustrating the steps of cleavage processing of a semiconductor laser element. As shown in FIG. 14A, a plurality of semiconductor layers each including an active layer are stacked successively on a semiconductor substrate, whereby a plurality of semiconductor layered bodies 131 formed as a single unit are provided. Furthermore, on the surface of the semiconductor layered bodies 131 on which the semiconductor layers are formed, a plurality of grooves 121 for cleavage are formed in parallel to each other at an equal interval for each interval of the semiconductor laser elements 101 in a resonator length direction (X direction in FIGS. 14A to 14C) of the semiconductor laser element 101 (see FIG. 10). Next, over the entire surfaces of the semiconductor layer uppermost portions of the semiconductor layered bodies 131, the surface electrodes 106 patterned in a lattice shape are provided in portions excluding cleavage regions, and the reverse-surface electrodes 107 are provided over the entire reverse surfaces of the semiconductor layered bodies 131. On each surface-electrode 106, the solder layer 104 made of an AuSn alloy is formed. The solder layer 104 is formed in a region narrower than the surface electrode 106, so that a part of the surface electrode 106 is exposed so as to surround the semiconductor layer 104. In order to cut out the semiconductor layered bodies 131 in a rectangular shape with a Y direction being a longitudinal direction, a plurality of short scribe points 122 are formed at an equal interval on each side edge in the resonator direction of the semiconductor layered bodies 131 in a rectangular shape.
Then, as shown in FIG. 14B, the semiconductor layered bodies 131, the surface electrodes 106, and the reverse-surface electrodes 107, which are formed as a single unit, are cleaved (primary cleavage) in the Y direction, using each scribe point 122 (see FIG. 14A) provided on the semiconductor layered bodies 131 cut out in a rectangle as a starting point, a plurality of bar-shaped element connected bodies 123 are obtained.
Next, as shown in FIG. 14C, each bar-shaped element connected body 123 (see FIG. 14B) is cleaved (secondary cleavage) along the grooves 121 for cleavage, whereby a plurality of semiconductor laser elements 101 are obtained.
Each semiconductor laser element 101 includes the surface electrode 106 on the front surface of the semiconductor layered body 131, and the reverse-surface electrode 107 on the reverse surface thereof. Furthermore, the solder layer 104 is provided on the surface electrode 106. A voltage is applied between the surface electrode 106 and the reverse-surface electrode 107, whereby laser light is output from an end face formed by primary cleavage.
In the above-mentioned process, in primary cleavage and secondary cleavage, generally, a pattern is recognized using the difference in reflection of light between the regions of the surface electrodes 106 and the other regions by irradiating the surfaces of the semiconductor layered bodies 131 with light, and a cleavage angle and a cleavage position can be adjusted from the recognized pattern. Particularly in primary cleavage, when the crystal direction of the semiconductor layered body 131 is not matched with the cleavage direction, the cleavage surface is not matched with the crystal surface. Therefore, level differences and scars are formed on an end face, and the end face does not function as an end face mirror. Furthermore, laser light is eclipsed, which substantially degrades characteristics.
In order to solve this problem, by increasing the difference in reflectance between the regions of the surface electrodes 106 and the other regions (e.g., the solder layer 104), the recognition ratio of the surface electrodes 106 is enhanced. For example, the surfaces of the surface electrodes 106 or the surfaces of the other regions are roughened with an etchant or the like to decrease flatness, and the like.
However, the AuSn alloy used in the solder layer 104 has very high flatness, and also has resistance to an etchant. Therefore, it is difficult to form unevenness on the surface. Thus, the clear difference in reflectance between the surface electrodes 106 and the other regions is not obtained, and pattern recognition cannot be performed satisfactorily. Furthermore, even after the primary cleavage, there are a number of steps of recognizing the pattern of the surface electrodes 106, aligning them, and defining the direction thereof, so that similar problems arise.
On the other hand, since the AuSn solder layer is dark green, the difference in color under visible light between the surfaces of the surface electrodes 106 and those of the other regions (e.g., the surfaces on which Pt is exposed) is clear. Therefore, if pattern recognition is performed by color extraction or the like, the above-mentioned problem may be solved. However, according to this method, the recognition property is unstable, and an apparatus having a color identification capability is expensive.

Semiconductor device and method for producing the same

Matsushita Electric Industrial Co., Ltd.


A golf ball retriever enables a golfer to quickly and easily recover the ball from a muddy ground hazardous location and the like. The retriever includes a rod, a swivel coupling adjustably mounted on the rod for positioning the retriever at selective angular positions with respect to the ground, a head member fixedly attached to the swivel coupling, and a cage mounted on the head member for capturing a single ball or multiple balls within, depending on the size of the cage being used. The retriever cage is formed of flexible looped wires which are spaced apart sufficiently to permit passage of the ball therein. The ball is captured by contacting the ball with the cage in a direct or peripheral manner. Cages of various capacities can be readily interchanged on the retriever.

1. Field of the Invention
The present invention relates to a golf ball retriever which enables a golfer to quickly and easily recover the ball which is lodged in a muddy ground hazardous location and the like. More particularly, the present invention pertains to a golf ball retriever having wire loop projections from the front end of an elongated handle, including one wire loop used as a retaining element for loosely engaging the other wire loops.
2. Description of the Prior Art
Retrievers for golf balls are known in the prior art. Many of the golf ball retrievers of the prior art require the golfer to have a substantial amount of patience and luck to actually capture the ball within a cage of the retriever. In a water hazardous situation, unclear water and/or wave movement on the water surface make(s) the retrieval uncertain of success. Many golfers find it extremely difficult to position the cage securely on top of the ball to perform the retrieval, especially if the ball is located in a muddy hole in the water hazardous location and the like. Further, when the handle of the retriever is a long telescopic type, that is, when the telescopic handle is extended to its operational length, that is, 10 feet, 15 feet, 18 feet and the like, the cage end becomes shaky and difficult to retain in a stationary position to enable the ball to be contacted. Further, mispositioning of the cage can agitate the water and give it a muddy and unclear condition to make the retrieval difficult or impossible. Further, retrievers of the prior art are difficult to operate when the retrieval operation is performed in a tight and small space. When a ball rolls, for example, into a small hole at a water hazardous location, the wedging of the ball into the cage enclosure and its retention therein are challenges which have met with little or no success by the prior art devices. Eventually, the golfer may give up trying to retrieve the ball and will move on in an angry mood which may not help the golfer's game.
Retrievers are broadly old in the patented prior art as illustrated in the references cited below.
The U.S. Pat. No. 373,289 issued Nov. 15, 1887 to William H. Hart discloses the feature of interchangeability of tools on a rod member.
U.S. Pat. No. 2,270,632 issued Jan. 20, 1942 to Robert R. Hasty discloses a golf ball rake or retriever comprising a telescoping handle and a cage which are adjustable to various angular positions with respect to each other.
U.S. Pat. No. 3,265,430 issued Aug. 9, 1966 to Homer T. Jenkins discloses a golf ball retriever comprising a retriever unit pivotally connected to a handle portion. The retriever unit having a wedging part of opposed members collects the ball by passing the ball through a pair of adjoining, resilient members to retain the ball therein.
U.S. Pat. No. 3,743,338 issued Jul. 3, 1973 to Robert W. Seeger discloses a golf ball retriever which is adapted to be removably attached to the end of an elongated rod. The retriever head comprises a plurality of elongated wires shaped into loops, which are secured within a tubular hub to form a cage-like structure. Upon contact with the ball, the opening of the loop is slightly expanded to receive the ball and then closes around the ball once it is within the cage-like structure.
Australia Patent No. 270,206 published May 12, 1966 to Kenneth E. Graham discloses a golf ball retriever having a cage-like member of a cylindrical formation of a diameter slightly larger than the ball.
None of the above-cited patents disclose or suggest alone or in combination the instant invention described and claimed herein.


A substitute reference signal input is incorporated into a state space controller for a scanning probe microscope to improve tracking efficiency.

For a typical scanning force microscope such as the atomic force microscope, a micromachined tip is scanned across a surface which results in the cantilever attached to the tip being deflected. Typically, the cantilever is controlled in the direction normal to the surface being scanned by an actuator such as a piezoelectric tube or a MEMS actuator. The deflection is typically detected by illuminating the cantilever using a laser beam. While it is possible to measure the deflection and use that as a position signal, large deflections may damage the tip and the surface being scanned. By ensuring that the deflection is close to some nominal point by moving either the cantilever or the surface being scanned, any potential damage is reduced. Hence, an additional signal besides the cantilever deflection is typically needed to provide an estimate for surface height.

Nano position sensing and surface estimation in scanning probe microscopes using reference estimation


A semiconductor device has a first area in which first and third semiconductor elements are formed, a second area in which second and fourth semiconductor elements are formed, and a third area located between the first and second areas. On the first to fourth semiconductor elements, a multilayer wiring layer including first and second inductors is formed. A through hole penetrating the semiconductor substrate is formed in the third area, and a first element isolation portion protruding from a front surface side of the semiconductor substrate toward a back surface side of the semiconductor substrate is formed in the through hole. Further, on the back surface side of the semiconductor substrate, the semiconductor substrate in the first area is mounted on the first die pad, and the semiconductor substrate in the second area is mounted on the second die pad.

In recent years, developed has been a technique in which an inductor is mounted on each of two semiconductor chips and a signal is transmitted and received between these two inductors in a non-contact manner. A device provided with such two inductors and a transmitter/receiver circuit is called a digital isolator.
For example, Patent Document 1 (Japanese Patent Application Laid-open No. 2011-54800) discloses a semiconductor device in which a first semiconductor chip and a second semiconductor chip are laminated so that the first inductor formed on a first semiconductor chip and the second inductor formed on a second semiconductor chip are opposed to each other. A first semiconductor element formed on the first semiconductor chip and a second semiconductor element formed on the second semiconductor chip can transmit a signal to each other by electromagnetic induction coupling via a first inductor and a second inductor.

Semiconductor device and method of manufacturing the same


The present invention includes the utilization of support blocks with angular surfaces which define semi-circular notches therein so that when assembled the semi-circular notches are aligned to form substantially circular regions for supporting a plurality of hoses individually in an offset and spaced relationship from one another. The ability to utilize support blocks which are designed in such a manner provides a space efficient manner for holding the individual hoses, while simultaneously, protecting the hoses from damage.

It is typically known that clamping devices are used for securing a high number of hoses or conduits on a wide variety of machines. Many such clamping devices allow adequate spacing for the hoses or conduits, either between the individual hoses or conduits themselves or from other adjacent components, to prevent damage to the hoses and conduits. One such clamping device includes a bent plate with a ladder construction capable of securing a plurality of hoses or conduits in a spaced and angled relationship to one another. The securing of the hose or conduit occurs through the use of a flexible fastener which is tightened around each hose at various rungs of the ladder.
In some instances, however, a clamping device is needed to secure individual hoses or conduits in an arrangement which is more space efficient and ensures higher protection from damage and instability. Therefore, it is important to utilize a clamp device which is easily manufactured and assembled and which can be adapted to hold a plurality of hoses or conduits with ease.
The present invention is directed to overcoming the problems as set forth above.

Hose clamp assembly offset mounting capability