A semiconductor device is provided, which is capable of miniaturization to a level corresponding to 1-Gb DRAMs. A first interlayer insulating layer is formed on or over a semiconductor substrate to cover a first-level conductive layer. First and second conductive sublayers of a second-level conductive layer are formed on the first interlayer insulating layer. First and second insulating caps are formed on the first and second sublayers, respectively. A lower contact hole penetrating the first insulating layer is formed to be self-aligned with the first and second sublayers. A conductive pad is formed on the first-level conductive layer in the lower contact hole to be electrically insulated from the first and second sublayers by an insulating spacer. A second interlayer insulating layer with an upper contact hole communicating with the lower contact hole is formed on the first interlayer insulating layer. A third-level conductive layer is formed on the second interlayer insulating layer to be contacted with the conductive pad through the upper contact hole.

1. Field of the Invention
The present invention relates to a semiconductor device and more particularly, to a semiconductor device in which upper and lower wiring layers are electrically connected to each other through a contact hole formed by a marginless formation technique.
2. Description of the Prior Art
In recent years, the integration scale of integrated circuits (ICs) has been becoming larger and larger through miniaturization of semiconductor device
Now, semiconductor devices with an ultra-large integration scale such as 1-Gigabit (Gb) Dynamic Random-Access Memories (DRAMs) have developed and experimentally fabricated according to the 0.15-.mu.m-order design rule. To cope with such the ultra-large-scale integration of devices, it has been strongly required to eliminate the mask-alignment margin for lithography processes in the fabrication process sequence.
However, the mask-alignment margin has been provided for preventing any problems occurring due to the possible mask-alignment error (i.e., misalignment) during the lithography processes. Therefore, this margin is very difficult to be completely eliminated.
Specifically, in the typical semiconductor device fabrication sequence, a lot of patterned layers, which are usually made of various materials such as metal, semiconductor, dielectric, and so on, are successively formed to be stacked on or over a semiconductor substrate. After a lower patterned layer is formed on or over the substrate, a next, upper layer is formed on the lower patterned layer thus formed. Subsequently, a patterned mask for this upper layer is formed on the upper layer. Then, using this patterned mask, the upper layer is patterned to be aligned with the lower patterned layer by a popular lithography technique.
In this case, it is usually that some placement or overlay error occurs between the upper and lower patterned layers and as a result, a mask-alignment margin is essential for the conventional semiconductor devices. However, this margin will be a cause inhibiting larger-scale integration of devices.
To realize the elimination of the mask-alignment margin, various techniques have been studied and developed, which are termed the "marginless formation techniques".
An important one of the known marginless formation techniques is to eliminate margins for contact holes which are typically formed in an interlayer insulating layer. This marginless formation technique for contact-holes is one of the key measures in view of enhancement of the integration scale and packing density of semiconductor devices, because the contact hole is used for electrically interconnecting a wiring layer with a semiconductor substrate or another wiring layer through an intervening insulating layer.
An important or prevalent one of the known marginless formation techniques for contact holes is termed the "self-aligned contact hole" technique. To realize this technique, concrete structures and/or formation methods have been examined in various ways.
The Japanese Non-Examined Patent Publication No. 4-159725, which was published in June, 1992, discloses a fabrication method of a semiconductor device that realizes the "self-aligned contact hole" technique.
In this conventional method, a pair of insulating sidewall spacers are formed at each side of a gate electrode of a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET). A contact hole is formed in an interlayer insulating layer covering the MOSFET to reach one of a pair of underlying source/drain regions formed in a semiconductor substrate. The contact hole is self-aligned with the gate electrode.
FIGS. 1A to 1F show the conventional method disclosed in the Japanese Non-Examined Patent Publication No. 4-159725.
First, as shown in FIG. 1A, a patterned field oxide layer 102 is formed on a main surface of a p-type silicon substrate 101 to selectively expose the main surface. A gate oxide layer 103 is formed on the exposed main surface of the substrate 101.
Next, a polycrystalline silicon layer 110 is formed on the field oxide layer 102 and the gate oxide layer 103 over the whole substrate 101 by a Chemical Vapor Deposition (CVD) process. A silicon nitride (SiN.sub.x) layer 105 is formed on the polycrystalline silicon layer 110 over the whole substrate 101 by a CVD process. The state at this stage is shown in FIG. 1A.
Then, the silicon nitride layer 105 and the polycrystalline silicon layer 110 are successively patterned by popular photolithography and Reactive-Ion Etching (RIE) processes. Thus, a gate electrode 104 is formed on the gate oxide layer 103 by the remaining polycrystalline silicon layer 110, and a cap 105a is formed by the remaining silicon nitride layer 105, as shown in FIG. 1B.
Using the gate electrode 104, the cap 105a, and the field oxide layer 102 as a mask, an n-type dopant such as arsenic (As) is selectively ion-implanted into the substrate 101, forming a pair of n-type source/drain regions 106 at each side of the gate electrode 104 in the surface region of the substrate 101. The state at this stage is shown in FIG. 1B.
Then, the uncovered gate oxide layer 103 is removed by using the cap 105a and the gate electrode 104 as a mask. However, this process is not always necessary. In other words, the gate oxide layer 103 may be left in the state shown in FIG. 1B.
Subsequently, a silicon nitride layer 107 is deposited over the whole substrate 101 by a CVD process to cover the MOSFET. The layer 107 is formed on the field oxide layer 102, the exposed substrate 101, the gate electrode 104, and the cap 105a, as shown in FIG. 1C.
The silicon nitride layer 107 is then etched back selectively, thereby forming a pair of sidewall spacers 107a at each side of the gate electrode 104, as shown in FIG. 1D. The bottoms of the sidewall spacers 107a are directly contacted with the substrate 101, i.e., the source/drain regions 106, because the gate oxide layer 103 has been removed.
Following this, a silicon dioxide (SiO.sub.2) layer 10B serving as an interlayer insulating layer is deposited by a CVD process over the whole substrate 101, covering the MOSFET, as shown in FIG. 1E.
A photoresist film 111 with a window 112 is formed on the interlayer insulating layer 108 thus deposited. As shown in FIG. 1E, an end of the window 112 is overlapped with a corresponding one of the pair of sidewall spacers 107a.
Using the photoresist film 111 as a mask, the interlayer insulating layer 108 is selectively etched by a wet etching process using buffered hydrogen fluoride (HF) Thus, a contact hole 108a is formed in the interlayer insulating layer 108 at a corresponding position to the window 112. The contact hole 108a uncovers a corresponding one of the pair of source/drain regions 106.
If the gate oxide layer 103 is not removed in the step in FIG. 1C, the gate oxide layer 103 is selectively etched during the etching process for the interlayer insulating layer 108.
After removing the photoresist film 111, a patterned wiring layer 109 is formed on the interlayer insulating layer 108 by popular processes. The wiring layer 109 is contacted with and electrically connected to the corresponding one of the source/drain regions 106 through the contact hole 108a of the interlayer insulating layer 108. The state at this stage is shown in FIG. 1F.
Another structure realizing the "self-aligned contact hole" technique was disclosed by T. Yamada et al. in the technical digest, pp. 35-38, 1989 International Electron Devices Meeting (IEDM), published in 1989.
In this conventional structure, a conductive layer is selectively grown on a source/drain region in self-alignment with a gate electrode using insulating sidewall spacers and a field oxide layer. An interlayer insulating layer formed to cover the selectively-grown conductive layer. A contact hole is formed in the interlayer insulating layer to extend the underlying conductive layer.
FIG. 2 shows the conventional semiconductor device disclosed in the 1989 IEDM technical digest.
A field oxide layer 122 is selectively formed on a main surface of a p-type silicon substrate 121. Gate electrodes 124 for MOSFETs are formed on the uncovered main surface of the substrate 121 through gate oxide layers 123, respectively. Silicon dioxide caps 125 are formed on the top faces of the gate electrodes 124, respectively. Pairs of insulating sidewall spacers 126 are formed at each side of the gate electrodes 124, respectively. Pairs of n-type source/drain regions 127 for the MOSFETs are formed in the surface region of the substrate 121 in self-alignment with the gate electrodes 124 and the sidewall spacers 126, respectively.
Silicon layers 128 are selectively grown on the exposed main surface of the substrate 121 between the sidewall spacers 126 and the opposing field oxide layer 122, respectively. The silicon layers 128 are doped with a dopant by ion-implantation to decrease their electric resistance. The tops of the silicon layers 128 are higher than the tops of the caps 125. One ends of the silicon layers 128 are located on the field oxide layer 122 to be overlapped therewith. The other ends of the silicon layers 128 are located on the corresponding silicon dioxide caps 125 to be overlapped therewith.
An interlayer insulating layer 129 is formed to cover the MOSFETs, the silicon layers 128, and the exposed filed oxide layer 122. Contact holes 129a are formed in the layer 129 to extend the corresponding silicon layers 128.
Wiring layers 130 are formed on the interlayer insulating layer 129 to be contacted with the silicon layers 128 through the corresponding contact holes 129a, respectively.
With the conventional method disclosed in the Japanese Non-Examined Patent Publication No. 4-159725, as shown in FIGS. 1A to 1F, the top and side faces of the gate electrode 104 are covered with silicon nitride cap 105a and the silicon nitride spacers 107a, respectively. Therefore, the contact hole 108a of the interlayer insulating layer 108 is formed in self-alignment with the gate electrode 104 without any margin. However, this method has the following two problems.
A first problem is that a large parasitic capacitance tends to occur in the vicinity of the contact hole 108a. This is because the gate electrode 104 and the wiring layer 109 are separated or electrically insulated by the silicon nitride spacer 107a with a relatively large dielectric constant in the vicinity of the contact hole 108a. This large parasitic capacitance will give a bad effect to high speed operation of the semiconductor device.
A second problem is that the hot-carrier resistance tends to degrade, resulting in deterioration in long-term reliability of the MOSFET. This problem is caused by the following reason.
As seen from FIG. 1F, the bottoms of the silicon nitride spacers 107a are directly contacted with the n-type source/drain regions 106, respectively. Therefore, hot carriers generated in one of the source/drain regions 106 that serves as a drain region tend to be trapped by a corresponding one of the spacers 107a. As a result, the electrical characteristics of the MOSFET such as the threshold voltage tend to fluctuate or deviate with time. This means that the hot-carrier resistance tends to degrade.
This phenomenon was reported by T. Mizuno et al. in the 1988 IEDM technical digest, pp. 234-237, published in 1988.
With the conventional structure disclosed in the 1989 IEDM technical digest, as seen from FIG. 2, the top and side faces of the gate electrode 124 are covered with the silicon dioxide cap layer 125 and the silicon dioxide spacers 126, respectively. Silicon dioxide has a smaller dielectric constant than that of silicon nitride. Therefore, the above first problem about the parasitic capacitance in the conventional method disclosed in the Japanese Non-Examined Patent Publication No. 4-159725 is solved.
Moreover, the sidewall spacers 126 are located on the corresponding gate oxide layer 123 and as a result, the above second problem about the long-term reliability in the conventional method disclosed in the Japanese Non-Examined Patent Publication No. 4-159725 is solved.
However, the structure in FIG. 2 has another problem relating to electrical insulation between the cap layer 125 and the selectively-grown silicon layer 128.
Specifically, when the contact holes 129a are formed in the interlayer insulating layer 129 by an etching process, the contact holes 129a may be located with some lateral shift with respect to the silicon layers 128 and as a result, they may be close to or contacted with the corresponding silicon-dioxide caps 125 due to mask-alignment error. If the contact holes 129a are close to the corresponding silicon-dioxide cap layers 125, leakage-current increase or short-circuit tends to occur between the wiring layers 130 and the corresponding gate electrodes 124. If the contact holes 129a are contacted with the corresponding silicon-dioxide caps 125, short-circuit will occur between the wiring layers 130 and the corresponding gate electrodes 124.
To prevent these disadvantages, it is necessary for the contact holes 129a not to be contacted or overlapped with the corresponding caps 125. In other words, the overlapped length 131 of each selectively-grown silicon layer 128 with the corresponding cap 125 needs to be longer than the alignment margin 133 of the corresponding silicon layer 128.
However, if the overlapped length 131 of the selectively-grown silicon layer 128 is designed to be longer than the alignment margin 133, the gap or space 132 between the opposing ends of the adjoining two silicon layers 128 becomes narrow. This leads to leakage current increase or short-circuit between these two layers 128 or the adjoining two wiring layers 130.
Thus, the electrical insulation between the wiring layers 130 and the corresponding gate electrodes 124 is a trade-off for the electrical insulation between the adjoining silicon layers 128 or the wiring layers 130. This means that it is difficult for the conventional structure disclosed in FIG. 2 to miniaturize the semiconductor device to thereby increase its packing density.
For example, for 1-Gb DRAMS designed with the 0.15-.mu.m rule, it is typical that the width of gate electrode 124 (i.e., the gate length) is set as approximately 0.15 .mu.m (150 nm), and that the alignment margin 133 for the contact holes 129a is set as approximately 0.05 .mu.m (50 nm). As a result, if priority is given to the electrical insulation between the wiring layers 130 and the corresponding gate electrodes 124, the space 132 of the selective-grown silicon layers 128 will be designed as a value less than 0.05 .mu.m (50 nm).

Semiconductor device with marginless contact hole


A debris catch assembly used between a plumbing fixture and drain piping. It has two strainers and structure for supporting the larger strainer in a superior position. Both strainers are configured with holes through their side and bottom surfaces, to catch all types of solid debris in waste fluid, including hair. During use, both strainers are rapidly removed and inserted without tools into their usable positions from a location above the plumbing fixture's drain opening. The larger strainer initially catches all of the debris. When it is filled up, it is withdrawn from the drain via finger engagement with a protruding stub, after which collected debris is emptied into a dry waste receptacle. During such cleaning, debris collects in the second strainer. When void of fluid, the second strainer can be removed from the drain for cleaning via a handle having a bent configuration that clears the strainer above it.

1. Field of the Invention
This invention relates to the field of plumbing traps and strainers, specifically to a plumbing assembly that is used under a plumbing fixture (sink, tub, etc.) to prevent drain blocking clogs. It has two strainers and structure for supporting them in desired positions of use between the plumbing fixture and the drain piping below it, with one strainer located above the other. The first strainer has a larger debris-catching volume than the second strainer and is in a superior position to the second strainer. Both have openings on their side and bottom surfaces configured to catch all debris, including hair and food particles, as well as dimensioned to allow oils and grease to be rinsed substantially from the collected debris. When the first strainer becomes filled with debris and/or wastewater flow through it begins to slow, it is lifted upwardly through the drain opening in the associated plumbing fixture and cleaned by emptying its contents into a dry waste receptacle. While the first strainer is removed from its preferred position of use, the second strainer is typically left in place to catch all debris in any standing water or other waste fluid passing through the plumbing fixture's drain opening. Should the openings in the first strainer become sufficiently blocked with debris to cause standing water in the associated plumbing fixture, the first strainer can be drawn upwardly through the standing water, with the second strainer functioning in a back-up role to catch any debris in the standing waste fluid as it enters into the plumbing fixture's drain opening and before it passes into a connected trap or drain piping, thus avoiding the risk of such debris building up sufficiently in the trap or drain piping to produce a fluid-blocking clog in a position that would be time consuming and/or costly to unblock. An important advantage of the present invention system is that both strainers are inserted and removed through the discharge opening of an associated plumbing fixture from a location above it. Thus, the person using a plumbing fixture having a connected present invention assembly does not have to bend over or drop to the knees to remove collected debris from either strainer. The first strainer can be easily removed via finger engagement with a protruding stub built into its interior surface near to its open top end. The second strainer has an elongated handle that permits easy withdrawal of the entire second strainer after the first strainer has been removed. Also, the handle of the second strainer is sufficiently short and has a bent configuration that allows it to clear the primary strainer above it so that when the second strainer is in its preferred position of use, it does not unseat the first strainer from its preferred positioning, whereby optimal debris catching is achieved.
2. Description of the Related Art
Debris traps for wastewater entering drain piping from a plumbing fixture are necessary to prevent the formation of fluid-blocking clogs that cause slow evacuation of wastewater from the plumbing fixture and/or wastewater accumulation in the plumbing fixture. P-traps or S-traps are typically placed under the fixture from which the wastewater is drained and clean out procedures are accomplished only from under the fixture, a disadvantage for those with arthritis, knee or hip injury, and advanced age. Also, special tools are usually needed to remove a P-trap or S-trap for cleaning, and strength may be required to accomplish the task, again a disadvantage for the infirm, injured, and elderly. Another prior art means of catching wastewater debris are strainers sitting in the uppermost portion of the drain piping connected to a plumbing fixture, such as the common kitchen sink strainer basket. However, many of them are shallow and not effective in high-volume wastewater applications, and/or do not have a filtering configuration that is effective in trapping hair and debris. Further, there is the issue of standing water, wherein once a strainer basket is removed, any standing water or other waste fluid in a plumbing fixture, along with associated debris, immediately moves through the plumbing fixture's drain opening and enters the drain piping below, where it poses a risk for creating a drain blocking clog in a position that would be difficult or expensive to remove.
While plumbing assemblies for trapping food, hair, and other debris are known to comprise multiple straining devices, such as the inventions disclosed in U.S. Pat. No. 989,410 to Peters (1911) and U.S. Pat. No. 394,213 to Scannell (1888). Both of the Peters and Scannell inventions have a superior strainer body with an independent strainer plate beneath it. The present invention has significant advantages over the both inventions and other known prior art, but the main difference is that the strainer plates of the Peters and Scannell inventions are not as easily and promptly removable from their positions of use within drain piping as is the second strainer of the present invention, which requires no separate tool, only finger engagement with its upwardly-directed handle. Also, Peters and Scannell disclosures do not teach the use of two reducing couplers, an adaptor, or the use of compression straps for reduced expense and ease of installation. Also, the tops ends of the Peters and Scannell strainers are seated adjacent to the discharge opening of the associated plumbing fixture, whereas the top flange of the present invention has an open-ended disposal flange immediately below the discharge opening and the top flange of its first strainer held by the lower portion of the disposal flange. Further, the Scannell strainer plate is held in place by a nut and bolt, with the only access to the nut being from below the plumbing fixture. Either a piercing tool or a specially designed wire for piercing (such as a coat hanger wire bent into a hook) would be required to engage one of the strainer plate holes and lift it upwardly from the stop ring that supports it, or a one would have to place at least one hand into the trap and grope through muck and debris to dislodge it from the stop ring so it can be removed. Either way, the Scannell strainer plate cannot be removed without difficulty. In addition, for lifting its strainer from the drain piping, the Peters disclosure reveals a cap connected to a chain that is secured to a portion of the plumbing fixture above the discharge opening. For lifting its strainer from the drain piping, the Scannell disclosure reveals a cross bar within the top strainer opening. Both the cap and cross bar are potential debris trappers, which could lead to premature blocking of waste fluid drainage. The protruding stub of the present invention is much smaller and poses much less of a risk of premature drain blockage. Another problem with the Scannell invention is that collection of debris on its strainer plate traps particles in a direct line with a p-trap, which acts as a sanitary water seal. Also in Scannell, it is contemplated for one to periodically empty its trap portion and remove collected semi-solid debris/grease material for burning. Thus, an operator of the Scannell invention has another task associated with its operation that requires working from below the plumbing fixture. In contrast, with use of the present invention, grease rinses freely away from debris collected in its strainer and does not form fluid-blocking clogs in the drain below. Further, in addition to both of its strainers being easily and readily removable by an operator working from above the plumbing fixture with which they are associated, not requiring the location and use of any tool for rapid removal and/or reseating of its strainers into its usable positions except operator fingers, and the present invention obviating the need for operators and maintenance personnel to bend over or work on the knees to remove drain-blocking debris clogs, which is difficult, time consuming, awkward, and not easily accomplished by those who are injured, infirm, or otherwise impaired in their movement, as well as the expense and delay of hiring a plumber, continued use of the present invention assembly further obviates the need for repeated use of drain cleaning chemicals to remove clogs from pipes and traps, which involve delay and can lead to pipe corrosion and premature pipe failure. Other disadvantages of prior art debris catch devices and procedures, which are overcome by use of the present invention, are the downtime associated with a drain blockage (particularly in business applications where a free-flowing drain is repeatedly needed, as in restaurant, animal grooming, and veterinarian applications), health hazard potential (as in the pet grooming industries, husbanding industries, kennels, and veterinarian applications where ticks associated with loosened pet hair in a drain can climb out of the drain), unpleasant odors associated with standing waste fluid, and the high cost burden placed upon wastewater treatment plants to remove food and other debris entering a drain. In contrast, the present invention debris catch system uses a fresh new approach for drain blockage prevention. A first elongated strainer sits lower in the drain than most prior art strainers, and has a larger catch capacity. Further, a second strainer supported in close proximity to the bottom of the suspended and easily removable first strainer has an elongated handle with a bent upper configuration and dimension that together allow the second strainer to be grasped from above the drain. The bent handle also allows positioning that is easily accessible from above an associated plumbing fixture, while not interfering with the proper support of the first strainer needed for effective debris capture. There is no invention known having the same structure as the present invention or all of its advantages.

Debris catch system for food preparation drains and other applications


A first silicon oxide film is formed on the surface of the semiconductor substrate in an area of a vertical transfer channel and a read gate contiguous with each other, and a silicon nitride film is formed on the first silicon oxide film. The silicon nitride film is isotropically etched by using a resist pattern formed on the silicon nitride film as a mask. A second silicon oxide film is formed on the surface of the etched silicon nitride film to form an insulating film containing silicon oxide films and a silicon nitride film. A photoelectric conversion element contiguous with the read gate on the opposite side of the vertical transfer channel is formed. The isotropical etching makes the silicon nitride film cover the vertical transfer channel, extend over the read gate, and have a tapered sidewall. A high quality solid state image pickup device can be manufactured.

FIG. 4A is a block diagram showing a main portion of a solid state image pickup apparatus assembling a solid state imaging pickup device, and FIGS. 4B and 4C are schematic plan views showing the structure of the solid state image pickup device. FIG. 4D is a schematic cross sectional view showing a portion of a pixel area of a solid state pickup device.
Referring to FIG. 4A, the structure of a solid state image pickup apparatus will be described. A solid state imaging pickup device 51 generates signal charge corresponding to an amount of light incident upon each pixel and supplies an image signal corresponding to the generated signal charge. A drive signal generator 52 generates drive signals (transfer voltage, etc.) for driving the solid state image pickup device 51 and supplies them to the solid state image pickup device 51. An analog front end (AFE) 53 subjects an output signal from the solid state imaging unit 51 to correlation double sampling, amplifies the sampled signal at an externally set gain, converts it into a digital signal, and outputs the digital signal. A digital signal processor (DSP) 54 processes an image signal supplied from the analog front end 53, such as recognition process, data compression and network control, and outputs the processed image data. A timing generator (TG) 55 generates timing signals for the solid state image pickup device 51, drive signal generator 52 and analog front end 53, to control the operations thereof.
The drive signal generator 52 includes, for example, a V driver for generating a vertical charge coupled device (CCD) drive signal. Signals supplied from the drive signal generator 52 to the solid state image pickup device 51 are a horizontal CCD drive signal, a vertical CCD drive signal, an output amplifier drive signal and a substrate bias signal.
As shown in FIG. 4B, the solid state image pickup device is constituted of: a plurality of photosensors 62 disposed, for example, in a matrix shape; a plurality of vertical CCDs 64 disposed near each column of the photosensors 62; a horizontal CCD 66 electrically connected to the vertical CCDs; and an amplifier circuit 67, connected to an output terminal of the horizontal CCD 66, for amplifying an output charge signal from the horizontal CCD 66. A pixel area 61 is constituted of the photosensors 62 and vertical CCDs 64.
The photosensor 62 is constituted of a photosensitive element, e.g., a photoelectric conversion element (photodiode) and a read gate. The photoelectric conversion element generates signal charge corresponding to an incidence light amount and accumulates them. Reading the accumulated signal charge to the vertical CCD 64 is controlled by a voltage applied to the read gate. The signal charge read to the vertical CCD 64 is transferred in the vertical CCDs (vertical transfer channel) 64 toward the horizontal CCD 66 (in a vertical direction). Signal charge transferred to the bottom end of the vertical CCDs 64 is transferred in the horizontal CCD (horizontal transfer channel) 66 in a horizontal direction, amplified by the amplifier circuit 67 and output to an external.
The photosensors 62 are disposed in a tetragonal matrix layout at a constant pitch in the row and column directions as shown in FIG. 4B, or disposed in a honeycomb layout in the row and column directions by shifting every second photosensors, for example, by a half pitch.
FIG. 4C is a schematic plan view of a solid state image pickup device having the honeycomb layout. The honeycomb layout has photosensors 62 disposed in a first tetragonal matrix layout and photosensors 62 disposed in a second tetragonal matrix layout at positions between lattice points of the first tetragonal matrix layout. Vertical CCDs (vertical transfer channels) 64 are disposed in a zigzag way between photosensors 62. Although this layout is called a honeycomb layout, the photosensor 62 of most honeycomb layouts is octangular.
As shown in FIG. 4D, formed in a p-type well 82 formed in a semiconductor substrate 81, e.g., an n-type silicon substrate, are a photoelectric conversion element 71 made of an n-type impurity doped region, a p-type read gate 72 disposed next to the photoelectric conversion element, and a vertical transfer channel 73 made of an n-type region disposed next to the read gate. A p+-type burying or covering region 71a is formed on the photoelectric conversion element 71. A vertical transfer electrode 75 is formed above the vertical transfer channel 73, with a gate insulating film 74 being interposed therebetween. A p-type channel stop region 76 is formed between adjacent photoelectric conversion elements 71.
The channel stop region 76 is used for electrically isolating the photoelectric conversion elements 71, vertical transfer channels 73 and the like. The gate insulating film 74 is a silicon oxide film formed on the surface of the semiconductor substrate 81, for example, by thermal oxidation. The vertical transfer electrode 75 is constituted of first and second vertical transfer electrodes made of, for example, polysilicon. The first and second vertical transfer electrodes may be made of amorphous silicon. The potential of the vertical transfer channel 73 is controlled by a voltage (drive signal) applied to the vertical transfer electrode 75 so that signal charge is transferred in the vertical transfer channel 73. The potential of the read gate 72 is controlled by a voltage (drive signal) applied to the vertical transfer electrode 75 above the read gate 72 so that signal charge generated and accumulated in the photoelectric conversion element 71 is read to the vertical transfer channel 73. An insulating silicon oxide film 77 is formed on the vertical transfer electrode 75, for example, by thermally oxidizing polysilicon. The vertical CCD 64 is constituted of the vertical transfer channel 73, upper gate insulating film 74 and vertical transfer electrode 75.
A light shielding film 79 of, e.g., tungsten, is formed above the vertical transfer electrode 75, with the insulating silicon oxide film 77 being interposed therebetween. Openings 79a are formed through the light shielding film 79 at positions above the photoelectric conversion elements 71. A silicon nitride film 78 is formed on the light shielding film 79.
As described above, the light shielding film 79 has the openings 79a above the photoelectric conversion elements 71 and prevents light incident upon the pixel area 61 from entering the region other than the photoelectric conversion elements 71.
A planarized layer 83a made of, e.g., borophosphosilicate glass (BPSG) is formed above the light shielding film 79. On this planarized surface, a color filter layer 84 is formed which is of three primary colors: red (R), green (G) and blue (B). Another planarized layer 83b is formed on the color filter layer 84. On the planarized layer 83b having a planarized surface, micro lenses 85 are formed, for example, by melting and solidifying a photoresist pattern of micro lenses. Each micro lens 85 is a fine hemispherical convex lens disposed above each photoelectric conversion element 71. The micro lens 85 converges incidence light to the photoelectric conversion elements 71. Light converged by one micro lens 85 passes through the color filter layer 84 of one of the red (R), green (G) and blue (B) and becomes incident upon one photoelectric conversion element 71. Therefore, the photoelectric conversion elements include three types of photoelectric conversion elements: photoelectric conversion elements upon which light passed through the red (R) color filter layer 84 becomes incident; photoelectric conversion elements upon which light passed through the green (G) color filter layer 84 becomes incident; and photoelectric conversion elements upon which light passed through the blue (B) color filter layer 84 becomes incident.
FIGS. 5A and 5B are schematic diagrams illustrating a manufacture method for a solid state image pickup device.
Referring to FIG. 5A, a semiconductor substrate 81, e.g., an n-type silicon substrate, is prepared and p-type impurities, e.g., boron ions, are implanted to form a p-type well 82.
In a surface layer of the well 82, n-type impurities, e.g., phosphorus or arsenic ions, are implanted to form a vertical transfer channel 73. A read gate 72 and a channel stop region 76 are formed by implanting p-type impurities, e.g., boron ions. An insulating film 74 is formed on the semiconductor substrate 81, the insulating film being an oxide-nitride-oxide (ONO) film including a thermally oxidized silicon oxide film, a silicon nitride film formed through chemical vapor deposition (CVD) and a silicon oxide film formed by thermally oxidizing the surface of the silicon nitride film.
A vertical transfer electrode 75 made of, for example, polysilicon, is formed covering the vertical transfer channel 73. The vertical transfer electrode 75 is made of, for example, first and second transfer electrodes stacked in the vertical direction. The vertical transfer electrode 75 is formed by depositing polysilicon on the insulating film 74, for example, by CVD and patterning it through photolithography and etching.
By using the vertical transfer electrode 75 as a mask or by using a resist pattern formed by coating resist on the surfaces of the vertical transfer electrode 75 and insulating film 74 and exposing and developing the resist, n-type impurities, e.g., phosphorus or arsenic ions are implanted to form a photoelectric conversion element 71. A burying layer 71a is formed by implanting p-type impurities, e.g., boron ions. The vertical transfer electrode 75 is thermally oxidized to form a silicon oxide film 77 on the surface thereof.
A horizontal CCD 66 is also formed in the semiconductor substrate 81 by using the above-described processes. An amplifier circuit 67 and the like are also formed.
Referring to FIG. 5B, a light shielding film 79 of, for example, tungsten, is formed above the silicon oxide film 77. Resist is coated on the light shielding film 79, exposed and developed to leave the resist in predetermined areas. By using this resist as a mask, the light shielding film 79 is etched to form an opening 79a above the photoelectric conversion element 71.
A silicon nitride film 78 is formed covering the light shielding film 79, and then a planarized layer 83a of BPSG is formed, for example, by CVD. For example, a deposited BPSG film is reflowed at 850° C. to form the planarized layer 83a. In addition to reflow, planarization may be performed, for example, by chemical mechanical polishing (CMP). Instead of BPSG, silicon oxide doped with impurities to lower a melting point may also be used.
On the planarized surface of the planarized layer 83a, a color filter layer 84 of three primary colors of red (R), green (G) and blue (B) is formed. For example, the color film layer 84 is formed by coating photoresist liquid mixed with granular pigment (pigment dispersed resist liquid) on the surface of the planarized layer 83a, exposing and developing it and curing it at a curing temperature of 220° C. Filter layers of three colors of red (R), green (G) and blue (B) are sequentially formed.
A planarized layer 83b is formed on the color filter layer 84 because the surface of the color filter layer 84 is irregular. For example, the planarized layer 83b is formed by coating material having the similar composition as that of transparent resin and curing it at a curing temperature of 220° C. Next, micro lenses 85 are formed on the planarized layer 83b.
FIGS. 6A and 6B are schematic cross sectional views showing the insulating film 74 near the read gate 72.
Referring to FIG. 6A, the insulating film 74 often adopts the ONO structure having the silicon nitride film 74b as an oxygen intercepting film sandwiched between the silicon oxide films 74a and 74c, as described earlier. Electrons constituting signal charge are accelerated by an electric field generated by a read voltage and partially become hot electrons, which may be trapped at the interface between the silicon nitride film 74b and silicon oxide film 74a, which may induce a temporal change in the read voltage.
The invention aiming to provide a solid state image pickup device is disclosed which device is stable, highly reliable, thin, and high in breakdown voltage and can suppress a temporal change in the read voltage caused by hot electrons (e.g., refer to Japanese Patent Laid-open Publication No. 2003-332556).
FIG. 6B is a schematic cross sectional view showing a characteristic portion of a solid state image pickup device according to the invention described in Japanese Patent Laid-open Publication No. 2003-332556. As shown, the solid state image pickup device of this invention includes a photoelectric conversion element 71 formed in a semiconductor substrate 81 and an insulating film 74 above a vertical transfer channel 73 near the photoelectric conversion element. The insulating film 74 has a lamination structure of silicon oxide films 74a and 74c and a silicon nitride film 74b. At least the silicon nitride film 74b of the insulating film 74 does not extend near to the upper end portion of the photoelectric conversion element 71.
FIGS. 7A to 7E are schematic cross sectional views illustrating a manufacture method for the characteristic portion of the solid state image pickup device according to the invention described in Japanese Patent Laid-open Publication No. 2003-332556.
Referring to FIG. 7A, on the surface of a p-type well 82 formed in a semiconductor substrate 81 of an n-type silicon substrate, an insulating film is formed having a three-layer structure of a silicon oxide film 74a having a thickness of 15 nm, a silicon nitride film 74b having a thickness of 50 nm and a silicon oxide film 74c having a thickness of 10 nm sequentially formed in this order from the bottom. Next, a heavily doped polysilicon film having a thickness of 0.4 μm is formed in order to form a vertical transfer electrode 30.
As shown in FIG. 7B, by using a resist pattern formed through photolithography as a mask, the polysilicon film is patterned by reactive ion etching (RIE) to form the electrode 30. By using the electrode 30 as a mask, the silicon oxide film 74c is etched.
As shown in FIG. 7C, a thermally oxidized film 31 is formed on the surface of the electrode 30 through thermal oxidation. The thermally oxidized film 31 is hardly formed on the silicon nitride film 74b. The thermally oxidized film 31 on the silicon nitride film 74b, if any, can be removed easily by an acid process.
As shown in FIG. 7D, after the thermally oxidized film 31 on the silicon nitride film 74b is removed by an acid process, the silicon nitride film 74b is selectively wet-etched with hot phosphoric acid, being laterally etched by a width of about 0.2 μm under the end portion of the electrode 30.
As shown in FIG. 7E, thermal oxidation is performed to bury the region under the end portion of the electrode without the silicon nitride film 74b.
In the solid state image pickup device formed in this manner, the insulating film under the electrode 30 near the photoelectric conversion element 71 has at its end portion a single layer structure of the silicon oxide film not containing the silicon nitride film 74b. It is therefore possible to maintain good read characteristics without a temporal change in the read voltage.
This single layer structure can be formed through isotropical etching without the necessity of a new photolithography process. A solid state image pickup device having good characteristics can be manufactured very easily with good workability.

Solid state image pickup device and its manufacture


A grid support structure is provided for a linear beam device having an axially centered cathode, an anode spaced therefrom and a grid disposed between the cathode and anode. The grid support structure maintains a proper grid-to-cathode spacing across an operating temperature range of the linear beam device. The grid is comprised of pyrolytic graphite, and includes a central active portion and a peripheral portion, with the peripheral portion comprising a plurality of evenly spaced elongated mounting holes. The grid support structure includes an inner grid support and an outer grid support. The inner grid support may include a plurality of axially extending posts that engage the mounting holes of the grid. The grid may further include resilient tabs that engage corresponding ramped surfaces to bias the grid into position.

1. Field of the Invention
The present invention relates to linear beam amplification devices having an electron emitting cathode and an RF modulated grid closely spaced therefrom, and more particularly, to a novel support structure for the grid that accommodates thermal expansion while maintaining an optimum grid-to-cathode spacing.
2. Description of Related Art
It is well known in the art to utilize a linear beam device, such as a klystron or travelling wave tube amplifier, to generate or amplify a high frequency RF signal. Such devices generally include an electron emitting cathode and an anode spaced therefrom. The anode includes a central aperture, and by applying a high voltage potential between the cathode and anode, electrons may be drawn from the cathode surface and directed into a high power beam that passes through the anode aperture. One class of linear beam device, referred to as an inductive output tube (IOT), further includes a grid disposed in the inter-electrode region defined between the cathode and anode. The electron beam may thus be density modulated by applying an RF signal to the grid relative to the cathode. As the density modulated beam propagates across a gap provided downstream within the IOT, RF fields are induced into a cavity coupled to the gap. The RF fields may then be extracted from the cavity in the form of a high power, modulated RF signal. An example of an IOT is provided by U.S. Pat. No. 5,650,751, to R. S. Symons, for INDUCTIVE OUTPUT TUBE WITH MULTISTAGE DEPRESSED COLLECTOR ELECTRODES, the subject matter of which is incorporated in the entirety by reference herein.
Since it is desirable to space the grid closely to the cathode surface, it thus must be capable of withstanding very high operating temperatures. In view of these demanding operating conditions, it is known to use pyrolytic graphite material for the grid due to its high dimensional stability and heat resistance. The pyrolytic graphite grid may be made very thin, with a pattern of openings formed therein, such as by conventional laser trimming techniques, to permit passage of the electron beam therethrough. The low coefficient of expansion of the pyrolytic graphite permits the grid to be heated by direct thermal radiation from the cathode and by dissipation of RF drive power when applied between the cathode and grid, without expanding the grid into the cathode and shorting these two elements together. As a result, the grid may be positioned very close to the cathode surface, permitting low RF drive voltage and high gain.
Nevertheless, a practical limitation on the efficiency of such linear beam devices has been the difficulty of supporting the grid in a proper position relative to the cathode surface. A metallic grid support structure, such as comprised of copper or stainless steel, will thermally expand at a much greater rate than the pyrolytic graphite grid, causing the relatively delicate grid to rupture. It is known to dispose a resilient, annular contact element between the grid and the metal grid support structure, such as a metallic braid, that compresses upon thermal expansion of the grid support structure to maintain proper spacing between the grid and the cathode surface. A drawback of this construction is that the resiliency of the contact element tends to degrade over time, especially due to the repeated thermal cycling of the device. Moreover, the addition of the contact element increases the complexity and associated cost of manufacture of the device.
Thus, it would be very desirable to provide a grid support structure for a linear beam device that maintains a proper spacing between the cathode and grid across the operating temperature range of the device. It would be further desirable to provide such a grid support structure which avoids the use of an additional resilient member.

Grid support structure for an electron beam device


A support assembly for displaying a banner on a flagstaff includes a base support for holding the base edge of a banner in extended condition, and an adjustable length deflector element extending from a point between the ends of the support element. The free end of the deflector element is attachable to the fabric of the flag at a central point within the flag's outer peripheral borders. The defector element is formed of resilient material and it is coupled to the support element by a guide bracket that includes a guide channel for bending the deflector element through a right angle. Dimensions of the guide channel and the deflector element are selected so that the deflector is free to slide telescopically within the channel to vary the length of the portion of the deflector extending from the support element. At the opposite end of the deflector, a right-angle projection engages a hole formed in the support element to retain the deflector in a desired extended position. By adjusting the distance between the free end of the deflector and the base edge of the flag, the support assembly may be adjusted specifically to various sizes of flags and various support angles between horizontal and vertical.

This invention relates generally to display supports for flags, banners and the like, and more specifically relates to a support assembly for preventing banners from wrapping around an associated supporting mast that is mounted in a non-vertical orientation.
Flags, pennants and banners, which for convenience will be referred to herein collectively, as banners, are frequently "flown" or displayed by attachment to vertical masts or flag poles. However, banners are also commonly displayed at the ends of masts and poles that are mounted at an angle part way between vertical and horizontal, because the surface patterns are more fully and clearly visible when a banner is suspended in that position. For further convenience in this specification, masts, poles and all other forms of elongate supports for banners and the like, will be referred to collectively, as staffs.
Although banners are known to be displayed more fully and effectively on staffs that are tilted from vertical toward horizontal, display of banners on such staffs is subject to a significant drawback that does not affect display on fully vertical staffs. Specifically, banners displayed in the outdoors are subject to widely variable natural wind forces that frequently result in the banner becoming wrapped or furled around the supporting staff.
In the of fully vertical support staffs, the forces of gravity naturally and inevitably cause a banner to "unwind" from around the staff when wind forces abate. On the other hand, in the case of staffs positioned at an angle between vertical and horizontal, natural "waving" or "flapping" of the attached banner often causes it to wrap around the semi-horizontal staff in response to wind forces, and to remain in that position, substantially furled, undisplayed and unattractive, when wind forces abate. When banners have become furled or wrapped around semi-horizontal staffs, they tend to remain in that position indefinitely due to the force of gravity, until they are manually unwrapped and restored to their "normal" unfurled display condition.
In the unfurled condition, banners hang freely, suspended from a single base edge attached to the staff. In the most commonly used display mounting arrangement, the base edge of the banner is engaged at its opposite ends and secured at those two points to the mounting staff, so that the base edge is extended to substantially its full length along and parallel to the axis of the staff. When the staff is tilted at an angle from the vertical, the base edge of the banner is extended effectively in the horizontal direction, so that the base edge becomes more and more nearly horizontal as the angle of tilt away from the vertical is increased. It is evident to even the most ordinary observation, that a banner is most fully extended for display purposes when the base edge is extended to its full length in the fully horizontal position. However, it is also evident that the "draping" effect that causes fabric to "roll" and creates the appearance of "fullness" when the base edge of a banner is extended at an angle between vertical and horizontal, adds substantially to the pleasing effect of the display and heightens the overall aesthetic appearance. It is highly desirable that any device intended to prevent a banner from becoming furled around a supporting staff, should also allow the banner to hang in a natural draped arrangement when it is at rest. Further, any such device should, preferably, allow the banner to "wave" as naturally as possible in reaction to ordinary wind forces.
In the prior art, various devices have been proposed for the prevention of wind-induced "furling" of banners around supporting staffs. These prior art devices have generally taken the form of rigid elongate bracing rods, positioned to extend along either the top or bottom edge of a banner generally at a right angle to the flag pole or staff. Displaying a banner in this way results in the upper or lower edge of the banner being held in an unnatural and unattractive position relative to the staff, preventing the pleasing effect achieved by natural "draping" when the banner is at rest. In others, the rod is merely attached fixedly along all, or a portion of, the upper or lower edge, without regard to fixing the relation of the rod to the staff and/or to the base edge of the banner; these devices are known to be subject to many of the same problems of wrapping, i.e. furling, or "fouling" the banner about the staff that affect banners mounted with no anti-fouling aids at all, and they are regarded as being minimally effective for their intended purpose. It can also be seen that a rigid support attached along an edge of the banner prevents that edge in particular from waving or rippling in any manner and further detracts from the desired pleasing aesthetic appearance of the display.
Accordingly, it is an object of this invention to provide an anti-furling support and display assembly for banners that permits the banner to drape in a natural and aesthetically pleasing manner when it is hanging at rest, supported on a staff positioned at an angle between horizontal and vertical.
It is another object of this invention to provide an anti-furling display support assembly that is readily and conveniently adjustable to accommodate a wide range of banner sizes and staff mounting angles.
It is still another object of this invention to provide an anti-furling display support assembly that can be attached to an associated banner conveniently and inconspicuously at a desirable and proper location without altering or damaging the fabric of the banner.
Yet another object of this invention is to provide a display assembly of the type described, which permits a banner to extend from the "at rest" position to a wind-induced "waving" position, while causing minimum interference with the natural flow of the fabric.
And, yet another and further object of this invention is to provide a device of the type described which is simple and inexpensive to manufacture and which can be installed easily without special knowledge or equipment.
These and other and further objects, features and advantages of this invention will be made more apparent by reference to the following specification and the accompanying drawings, in which:


A high frequency filter includes a dielectric plate 8, an outer conductor 9 formed on the one surface of the dielectric plate 8, a plurality of strip conductors 10a-10d formed approximately in parallel on the other surface of the dielectric plate 8, a strip conductor 15 formed in a direction crossing the strip conductors 10a-10d, short-circuiting portions 11 and 16 connecting the one ends of the strip conductors 10a-10d and the strip conductor to the outer conductor 9, respectively, and further comprises a plurality of resonators 110a-110d constructed by the strip conductors 10, a plurality of capacitors (gaps) 12 coupling the resonators to each other to be connected in series, capacitors 13 connecting the strip conductors 10a, 10d to an input terminal and an outer conductor, respectively, a resonator 200 constructed by the strip conductor 15, and a plurality of capacitors (gaps) 33 connecting the strip conductors 10a, 10d to the resonator 200.

1. Field of the Invention
The present invention relates to a high frequency filter mainly used in a VHF band, UHF band, a microwave band and a millimeter wave band and more particularly to polarize it and improve its characteristic.
2. Description of the Related Art
FIG. 33 is a schematic diagram showing a conventional high frequency filter disclosed in e.g. Japanese Utility Model Unexamined Publication No. Hei 1-101603.
In the figure, reference numeral 8c denotes a dielectric block.
Reference numeral 9 denotes one of outer conductors each made of a conductive film formed on the remaining sides other than one side (upper side in the figure) of all the sides of the dielectric block 8c. The outer conductors are in intimate contact with the outer wall of the dielectric block 8c.
Reference numeral 10c denotes one of inner conductors each made of a conductive film formed in intimate contact with the inner wall of each of first through-holes 23 described later. The inner conductors 10c are continuously connected to the outer conductors 9 on the outer wall of the dielectric block 8c at their one ends (the bottom side in the figure).
Reference numeral 23 denotes one of first four through-holes passing through between opposite faces of the dielectric block 8c (upper face and bottom face) and arranged in substantially parallel. The first through-holes 23 are arranged in substantially parallel to the remaining faces (side faces in the figure).
Reference numeral 24 denotes one of three second through-holes formed in the same manner as the first through-holes 23 and arranged in substantially parallel between the adjacent first through-holes 23. Each second through-hole 24 has a smaller diameter than that of each first through-hole 23.
The inner conductors 10c, first through-holes 23 and second through-holes 24 constitute 1/4 wavelength resonators 120a to 120d with their one ends opened and other ends short-circuited.
Reference numeral 25 denotes one of first electrodes formed on the surface of the dielectric block 8c at the open ends (upper side in the figure) of the 1/4 wavelength resonators 120a and 120d at both ends. Each first electrode is continuously connected to each inner conductor 10c.
Reference numeral 26 denotes a dielectric plate having substantially the same shape as the one side (upper face in the figure) of the dielectric block 8c. The dielectric plate 26 is overlaid on this surface of the dielectric block 8c.
Reference numeral 27 denotes one of third through-holes provided on the dielectric plate 26 so as to coincide with the opening positions of the first through-holes 23 at the open ends of the 1/4 wavelength resonators 120a and 120b at both ends.
Reference 28 denotes one of second electrodes each made of a conductive film in intimate contact with the surface of the dielectric plate 26 and formed on the periphery of each of the second though-hole at both ends.
Reference numeral 29 denotes a conductor for connecting said second electrodes 28 to each other.
Reference numeral 30 denotes a dielectric tube, and P1 and P2 denote terminals provided on the dielectric tube 30, respectively.
Each first electrode 25 and each second electrode 28 are opposite to each other through the dielectric plate 26 to constitute a capacitor. The terminal P1 and the terminal P2 are partially inserted into dielectric tubes 30, respectively and into the through-holes 23 at both ends. Thus, the inner conductor 10c, dielectric tube 30, terminal P1 or P2 constitute a capacitor for input/output coupling.
An explanation will be given of the operation theory. First, the presence of the second through-holes 24 generates inequality in permittivity within the dielectric block 8c. This inductively couples the adjacent resonators to each other by mainly a magnetic field. The amount of coupling can be adjusted by the distance between the resonators 120 and size of the second through-hole 24. The resonators 120a and 120d at both ends are mainly inductively coupled with each other through the intermediate resonators 120b and 120c, and also slightly capacitively coupled with each other through the first electrodes 25, second electrode 27 and connecting conductor 29.
Now it is assumed that the length of the inner conductor 10c is adjusted so that the four resonators 120a to 120d are resonated at the same frequency f0. On this assumption, at the frequency f0, the four resonators in a resonance state are strongly inductively coupled with one another. Thus, a wave incident to the terminal P1 is guided to the resonator 120d through the resonators 120a to 120c and taken out from the terminal P2. On the other hand, at the frequency other than f0, the resonators 120a to 120d are very weakly coupled with one another so that most of the electric power of the incident wave to the input/output terminals is reflected. In this way, the conventional high frequency filter as shown in FIG. 33 can serve as a band-pass filter.
In the high frequency filter as shown in FIG. 33, the resonators 120a and 120d at both ends are mainly coupled with each other through the intermediate resonators 120b and 120c and also slightly capacitively jumping-coupled with each other by the first electrodes 25, second electrodes 27 and connecting conductor 29. Generally, the passing phase of the resonator is +90.degree. at the frequency lower than the resonance frequency, 0.degree. at the resonance frequency and -90.degree. at the frequency higher than the resonance frequency. The passing phase of the capacitive coupling means in series connection is +90.degree. whereas that of the inductive coupling means in series connection is -90.degree.. In the main coupling between the resonators 120a and 120d at both ends, which passes through two resonators and three stages of inductive coupling means, the total passing phase is -90.degree. at the frequency lower than f0 and -450.degree. (=-90.degree.) at the frequency higher than f0.
On the other hand, since the jumping-coupling is capacitive, the passing phase due to it is +90.degree. irrespectively of the frequency. Thus, in the conventional high frequency filter as shown in FIG. 33, the passing phase due to the main coupling and that due to the jumping-coupling are opposite. For this reason, attenuation poles are generated in the frequencies lower and higher than the passing band, thereby making the attenuation characteristic abrupt. In this case, the amount of jumping which is very little has little effect on the loss of the passing band.
In order that the jumping-coupling is capacitive, it should be noted that the electric length of a connecting conductor must be much shorter than the wavelength, and in FIG. 33, the permittivity of the dielectric plate 26 must be much smaller than that of the dielectric block 8c.
FIG. 34 is a schematic diagram showing the conventional high frequency filter disclosed in J-UM-3-44304, for example.
In the figure, reference numeral 8 denotes a dielectric plate.
Reference numeral 9 denotes an outer conductor of a conductive film formed in intimate contact with the one entire surface (bottom surface in the figure) of the dielectric plate 8.
Reference numeral 10 denotes one of strip conductors of a conductor film arranged in parallel and formed in intimate contact with the other surface (upper surface in the figure) of the dielectric plate.
Reference numeral 11 denotes a short-circuiting end surface of a conductive film formed in intimate contact with the side surface of the dielectric plate and continuously connected to the outer conductor 9 and strip conductors 10.
The dielectric plate 8, outer conductor 9, strip conductors 10 and short-circuiting end surface 11 constitute an approximately 1/4 wavelength microstrip line type resonator 110 with the one end opened and other end short-circuited.
Reference numeral 13 denotes one of capacitors provided on the strip conductors 10, respectively.
Reference numeral 14 denotes one of conductor ribbons each having the one end connected to the capacitor 13 and the other end connected to a strip conductor 31 described below.
Reference numeral 31 denotes the strip conductor of a conductor film in intimate contact with the other surface (upper surface in the figure) of the dielectric plate 8. The strip conductor 31 is arranged in a direction crossing the strip conductors 10 in the vicinity of the open ends of the strip conductors where the capacitors 13 are provided.
The dielectric plate 8, outer conductor 9 and strip conductor 31 constitute a main line 32.
Reference symbols P1 and P2 denote terminals, respectively. The open ends of the two strip conductors are connected to the strip conductor 31, with a distance of approximately 1/4 wavelength therebetween, through the capacitors 13 and conductor ribbons 14.
In operation, assuming that the resonance frequency of the resonator 110 is f0, at the frequency lower than f0, the resonator 110 serves as an inductance to constitute a series resonance circuit together with a capacitor 13. Now assuming that the series resonance frequency is f1, most of the electric power of the incident wave at the frequency of f1 incident on the terminal P1 is reflected owing to the resonance in the series resonance circuit. On the other hand, at the frequency other than f1, without being influenced by the resonators 110, most of the electric power of the incident wave on the terminal P1 is guided to the terminal P2. In this way, the conventional high frequency filter as shown in FIG. 34 serves as a band-stop filter.
Since the high frequency filter is constructed as described, where the resonators 120a to 120d and the jumping-coupling means such as the electrodes 25 and 27 are formed on the same dielectric block or plate, or otherwise the permittivity of the dielectric material constituting a filter is relatively small, the electric length of the connection line (connection line 29) of the jumping connecting means becomes fairly long, thus making it impossible to form a desired attenuation pole.
In connection between the strip conductors 10 and strip conductor 31, in addition to the connection in the manner of a lumped constant circuit by the capacitors 13, the direct connection by fringing is provided so that both strip conductors cannot be arranged adjacently to each other. For this reason, the conductor ribbons are required for connecting the capacitors 13 to the strip conductors 31. This makes the assembling of the high frequency filter complicated.

High frequency filter having a plurality of serially coupled first resonators and a second resonator


Methods and systems for displaying medical images are provided. The method includes performing three-dimensional (3D) volume visualization on a plurality of two-dimensional (2D) images acquired continuously. The method further includes combining the 3D volume visualizations to form a plurality of four-dimensional (4D) volumes representing the 3D volume visualizations over a period of time and displaying at least one 4D volume.

This invention relates generally to medical imaging systems, and more particularly, to systems that display images resulting from scans performed by medical imaging systems.
Medical analysis and diagnosis is often performed with medical imaging system having displays to display the results of a scan of a patient. Analysis of the images can be very time sensitive or critical with added time possibly resulting in increased risk to the patient due to the patient condition. This added time can result in increased risk of permanent injury or death. For example, a brain attack is a time critical patient condition where every minute counts. Accordingly, rapidly determining the appropriate diagnosis and treatment path is often critical and can reduce the chances of permanent injury or death. In particular, for a patient showing signs of a possible stroke, it is important to quickly determine whether there is brain hemorrhaging. Increased time in diagnosis can increase the likelihood of permanent injury. If the diagnosis is not correct, for example, if there is no stroke and a patient is given a stroke treatment, serious harm and death can result. Improper diagnosis can lead to improper treatment. Thus, fast and robust diagnosis and appropriate patient treatment helps to ensure improved patient outcomes.
Known methods for displaying medical image data to analyze for diagnosing a patient can be difficult to view or navigate, thereby increasing the time for diagnosis. For example, due to the basic complexity of some anatomical regions, such as the brain, existing segmentation techniques do not allow for a clean visualization. Similarly, these systems display a single image in time and may not provide the clinician with all of the information needed for a proper diagnosis. The clinician often has to view different images, which may be on different screens or may not be able to be viewed simultaneously. This increases the difficulty in reviewing and analyzing the images, thereby increasing the time for a proper diagnosis.
Thus, known methods and systems for displaying medical images can be difficult to navigate and review. Further, these system can be cumbersome or awkward to use, further adding time before a proper diagnosis. This added time can result in serious consequences.

Method and system for displaying a cine loop formed from combined 4D volumes


A drilling system is provided for drilling a borehole into an earth formation, the drilling system comprising pump means for pumping drilling fluid into the borehole and discharge means for discharging drilling fluid from the borehole. The discharge means comprises at least one pressure chamber for temporarily accommodating drilling fluid being discharged from the borehole, and control means for controlling the fluid inflow into each pressure chamber.

WO-A-0079092 discloses such drilling system, whereby the discharge means control the discharge of drilling fluid,and therewith the flow of drilling fluid through the annular space. Therefore the discharge conduit is provided with a controllable outlet valve. As an alternative WO-A-0079092 describes an injection pump arranged to pump injection fluid via an injection nozzle into the discharge conduit in a direction opposite to the direction of flow of drilling fluid through the discharge conduit. By controlling the injection fluid, the resistance in the discharge conduit can be controlled.

System for controlling the discharge of drilling fluid


A die cushion apparatus of a press machine in which a discharge opening of a fluid hydraulic pump/motor is directly connected to a pressure chamber on a cushion pressure production side of a fluid hydraulic cylinder and the torque of a rotating shaft of the fluid hydraulic pump/motor is controlled by an electric motor to control a pressure (die cushion pressure) of the pressure chamber on the cushion pressure production side. It is therefore possible to control the die cushion pressure with excellent responsiveness with respect to a die cushion pressure command and prevent occurrence of a surge pressure. The die cushion apparatus also has excellent energy efficiency since energy required for a die cushioning action that a cushion pad receives when effecting die cushioning of a press machine is regenerated as electrical energy through the fluid hydraulic cylinder, fluid hydraulic pump/motor, and electric motor.

(a) Pneumatic Die Cushion Apparatus
A pneumatic die cushion apparatus is constructed by connecting a pneumatic cylinder that supports a cushion pad and a steel cylinder in which a low pneumatic pressure is accumulated. A pneumatic die cushion apparatus has advantages including convenience and that fact that a surge pressure does not occur since it uses a compressible fluid.
On the other hand, there are disadvantages such as a problem that the size of the apparatus increases due to the need to provide a pit accompanying upsizing of pneumatic cylinders, performance problems such as vibrations upon collision accompanying pressure fluctuations in the compressible fluid or dumping deficiencies, and a problem that additional mechanisms are required in order to overcome a lack of knock-out operation controllability (e.g. an additional mechanism is required when locking a cylinder at the bottom dead center of a press). Accompanying the recent technological advances in the press industry, this may be called an old-style die cushion apparatus.
(b) Oil Hydraulic (Servo) Die Cushion Apparatus
A die cushion apparatus of a press has been proposed that comprises an NC servo valve that obtains a cushioning action by controlling the pressure of cushion cylinders of a cushion pad, and a positional control servo valve that executes pre-acceleration, auxiliary lifting, locking, and lifting of a cushion pad by controlling the pressure oil that is supplied to an upper chamber and a lower chamber of an oil hydraulic cylinder that supports the die cushion pad (Patent Document 1).
This die cushion apparatus can control a surge pressure by pre-accelerating the cushion pad.
(c) Electric (Servo) Type Die Cushion Apparatus
Patent Documents 2 and 3 disclose die cushion apparatuses of presses that control a pressing force for a cushion pad with an electric (servo) motor and screw and nut mechanism, link mechanism, or rack and pinion mechanism.
An advantage mentioned is that control of the pressing force is facilitated since the cushion pad is driven via an electric (servo) motor with good responsivity and (in comparison to hydraulic oil or the like) a mechanism with high rigidity (no loss of responsivity).
(d) Regarding Other Similar and Often Seen Apparatuses
Patent Document 4 discloses a plastic working device according to a hydraulic drive system that, although not a die cushion apparatus, is close thereto with respect to the outward configuration.
This plastic working device according to a hydraulic drive system has a closed combination circuit that is formed by connecting a two-way operation type oil hydraulic cylinder and a two-way discharge type hydraulic pump in a one-to-one condition without mounting a valve therebetween. The plastic working device is configured to drive the oil hydraulic cylinder via the hydraulic pump by driving the hydraulic pump using a direct current servo motor, and to subject a plate material to plastic working using a punch that is driven by the oil hydraulic cylinder.
Patent Document 1: Japanese Patent Application Laid-Open No. 7-24600
Patent Document 2: Japanese Patent Application Laid-Open No. 5-7945
Patent Document 3: Japanese Patent Application Laid-Open No. 6-543
Patent Document 4: Japanese Patent Application Laid-Open No. 10-166199


A facility for selectively suppressing notifications on a portable device is described. The facility accesses data characterizing the condition of the portable device. The facility infers from the accessed data that that the portable device is being carried by a person who is viewing content being played by a media player device. In response to this inference, the facility determines whether notifications should be suppressed on the portable device. If the facility determines that notifications should be suppressed on the portable device, it causes a wireless communication to be transmitted to the portable device instructing the portable device to suppress notifications.

Audio/video programs have the capacity to be highly engaging, entertaining, and/or informative. These can include, for example, television programs, movies, plays, music videos and concerts, classes, video blogs, speeches by government officials, space launches, natural disaster coverage, etc.
In some cases, people view audio/video programs in partly- or fully-specialized rooms designed to improve the viewing experience. These rooms may include a large, high-resolution video screen; a high-fidelity, high-power audio system; comfortable furniture; optimized light levels; sonic isolation; etc.

Automatically suspending or reducing portable device notifications when viewing audio/video programs


An access control system and method is provided for an activities center wherein activities are available for customers. The control system employs a plurality of access cards, a comptroller processor, at least one credit station and a plurality of access stations. Each access card is encoded for a respective customer, and the comptroller processes data, creates customer account files correlated to each customer's account file identifier, stores the customer account files, verifies customer account files to determine availability of credit and issues either approval or disapproval. The credit station reads an account file identifiers on an access cards and signals the processor to open the customer account file. An access station is associated with each activity and reads an access card to signal the comptroller processor to open the customer account file. Debit circuitry within each access station generates a debt signal corresponding to a selected cost debt for the respective activity, and the comptroller processor then generates approval or disapproval depending on the customer account credit for that activity. The access station has receiving circuitry responsive to the approval or disapproval signals from the comptroller processor to grant or deny customer access to the selected activity. A plurality of types of credit are used, and the comptroller processor maintains corresponding subaccounts, and the customers may allocate payment at the credit station among the types of credit available.

In virtually every business setting wherein customer access to goods or services is provided on a fee basis, the need exists to both control access and account for payment of fees where access is given to a user. In many instances, the user selects the items or services desired and pays for the same on an item-by-item basis. In such cases, a cashier is provided to total the charges for such items and to handle the financial transaction as the intermediary between the business and the customer. In other environments, it is often more desirable to provide a customer with access to an event, item or even to an area on a credit unit or time interval basis so that an attendant is not required at the actual time of the commercial transaction. For example, a customer at a grocery store typically selects the food items for purchase and takes these items to a cashier who tallies the total purchase price, accepts payment from the customer, and returns any change due from the funds provided by the customer. Examples of the latter type of control and payment can encompass a wide variety of commercial enterprises. For example, access to a hotel room is usually based on an interval of time, and it is often desirable to provide the customer with promotional credits which can be redeemed for other items such as courtesy gifts and the like. Other enterprises utilize tokens or coupons denominating unit credits which may be used in place of money for permitting access to a game or an event; example here include theatre ticket or pass books, concert series tickets, and token machines such as slot machines and other gaming devices. While the present invention has potentials in these as well as other commercial endeavors, of especial interest to the present invention is the use of the access control apparatus and system of the present invention as applied to recreational facilities and activities.
Recreational activities have always been part of human existence, and the variety of leisure activities developed by various cultures is almost endless In modern times, the increase in leisure time has created a corresponding increase in the demand for varied recreational activities; technology has responded with leisure events and recreational devices of increased diversity. The advent of micro-processing circuitry has, for example, opened a huge market for video game equipment beyond the more limited mechanical equipment of a few years ago.
Parents, in particular, have found an especial need for wholesome recreational activities for their children Different recreational facilities allow for varying degrees of parental participation in the activities of the children, ranging from active participation to mere observance. Accordingly, a trend has been to construct activity centers which offer different activity events, play areas and game machines. The most successful of these facilities typically provide recreational activities which appeal to different age groups, including not only children and youths but parents as well. A difference in activities is also desirable due to individual tastes and levels of skill. Therefore, those facilities which offer wide varieties of activities appealing to a broader customer base.
Operation of recreational facilities, however, is not without its drawbacks. These difficulties usually comprise three types. First, there can arise supervisional difficulties due to customer volume and the fact that customers include small children and even unattended youths. Second, difficulties arise in monitoring and controlling access to the various events, areas and activities so as to prevent unauthorized use. Third, difficulties are present in monitoring the cash flow in recreational facilities.
The present invention concerns the second and third of these difficulties experienced in existing recreational facilities management. Heretofore, access to the activities provided by a recreational facility has generally been one of three ways. One such technique has been the "pay as you go" method wherein a user pays for each event at the time of use. While this procedure in some instances is acceptable, it is labor intensive since each activity must be staffed, on one hand, and extra personnel are needed for the collection and counting of money on the other hand. This technique also creates many opportunities for theft therefore increasing the need for management supervision over employees. In order to eliminate some of the problems inherent with a cash based system, some recreational facilities employ the use of game tokens or coupons. This procedure, while eliminating some of the staffing problems, does little to alleviate the theft and unauthorized use since there is still the temptation to steal and resell the tokens on a black market.
Finally, some recreational facilities have elected to eliminate many of the above mentioned problems by simply establishing a single entry fee for unlimited use, usually on a day-to-day basis, for the facility. While this technique eliminates some problems, other disadvantages arise since a single use fee is not always practical and customer fees may be set at an artificially high rate. This procedure also does not allow those customers to pay only for the activities which they use; thus, these customers subsidize more intensive use by a few. This naturally acts as a negative selling point to many customers, and, in some instances, may reduce overall use.
Accordingly, there is a substantial need for facilities access and control apparatus and methodology which more efficiently manages access to events, areas and activities from an operational standpoint. There is further a need for apparatus and methodology which more securely manages the cash flow of a facility offering services and goods to users. There is also a need for improved apparatus and methodology which eliminates the labor intensity of access management. Finally, there is an especial need for an apparatus and methodology which simplifies use of a recreational facility and which allows customers a variety of options for use in payment and in the selection of games and activities.

Apparatus and method for accessing events, areas and activities


A method for generating a composite image includes receiving a separate image into a computer system, comparing the separate image to the composite image so as to generate a mismatch value, and modifying at least one of the composite image and the separate image to reduce the mismatch value.

Often, there is a need to identify a person through comparison of the person's face with a recorded image of a face. Such situations regularly arise in police investigations where, for example, the police search for a suspect on the basis of a security camera image.
Difficulty arises when the image used for comparison is of poor quality. The lighting in the store might have been poor. The subject might not have been facing the camera or part of the subject's face might have been hidden by bystanders. The image might have been recorded on a medium such as magnetic tape subject to deterioration.
There are advantages in converting the recorded image to a standard frontal and profile composite image similar to the image composed by a person under the guidance of a police artist. Such an image can easily be the basis for comparison. The image can maintain its fidelity despite noise added in transmission and copying. The image can be updated to allow for the passage of time or for modifications associated with a particular area, such as a beard.
Construction of a composite image is an interactive process. A witness working with a police artist guides manipulation of the appearance and location of features such as ears and eyes until she feels that the composite image resembles her memory of the face. A person working with a separate image of a face instead of with a witness has the advantage of not relying on memory. However, the person working with a separate image, lacking a witness to tell him when to stop, relies on his own criteria in deciding when resemblance of the composite image to the separate image is close enough. With an unlimited number of combinations of features and locations available, the person working with a separate image may find himself trying one combination after another, unable to home in on the combination associated with a composite image most similar to the separate image.