A method is provided for manufacturing a multi-layer wiring circuit substrate. A first metal layer is selectively etched in first areas to reduce a thickness of the metal layer in the first areas and to form protrusions in other areas which extend above the etched areas. An interlayer-insulating layer is formed to overlie the etched areas of the first metal layer. The interlayer-insulating layer has an inner surface which confronts the etched first areas and an outer surface remote from the inner surface, such that the protrusions extend through the interlayer-insulating layer and have ends exposed at the outer surface. A second metal layer is then provided in conductive communication with the exposed ends of the protrusions, and the first and second metal layers are selectively patterned from surfaces remote from the interlayer-insulating layer.

1. Field of the Invention
The present invention relates to a wiring circuit substrate used for mounting electronic devices, such as integrated circuits (ICs) and large scale integrated circuits (LSI circuits). Particularly, the invention relates to a wiring circuit substrate that allows high-density mounting to be implemented.
Furthermore, the present invention relates to a manufacturing method for the aforementioned wiring circuit substrate.
2. Description of the Related Art
FIGS. 54A to 54F and 55A to 55C are used to describe a conventional example of a high-density-mounting wiring circuit substrate. These figures are cross-sectional views illustrating a manufacturing method for the conventional wiring circuit substrate in the order of steps (A) to (I) described below.
Step (A)
First of all, as shown in FIG. 54A, a base 1 is prepared. The base 1 is made of an insulating sheet having a thickness of 25 to 100 μm. In the base 1, interlayer-connecting openings 2 are formed by using a punching machine or a drill or by performing laser processing.
Step (B)
Subsequently, as shown in FIG. 54B, conductive paste 3 (made of a main material, for example, such as silver or copper) is filled into the openings 2 by using a printing method for example. Thereby, the insulating base 1 is arranged to be a semi-cured sheet A in which the conductive paste 3 is filled into the openings 2.
Step (C) and Step (D)
Subsequently, as shown in FIG. 54C, metal foils 4 made of, for example, copper, are individually arranged over two faces of the sheet A. Then, as shown in FIG. 54D, the metal foils 4 are overlaid by using a pressing/heating press. Thereby, a multilayer body is formed such that the metal foils 4 are formed on the two faces, an insulating sheet is provided therebetween, and the metal foils 4 on the two faces are electrically connected to each other via the conductive paste 3 in the openings 2.
Step (E)
Subsequently, resist films 5 are formed on the metal foils 4. The resist films 5 have the same pattern as that of conductor circuits that will be formed. FIG. 54E shows a state after the resist films 5 are formed.
Step (F)
Subsequently, using the aforementioned resist films 5 as masks, etching is performed for the aforementioned metal foils 4, thereby forming conductor circuits 6, as shown in FIG. 54F. According to the above, layers are separated and arranged on the two faces via the insulating sheet (base) 1, and a multilayer body B having the conductor circuits 6 interlayer-connected to each other via the conductive paste 3 in the opening 2 is formed.
Step (G)
Subsequently, as shown in FIG. 55A, on individual two faces of the aforementioned multilayer body B, insulating sheets 1a having openings 2 filled with conductive paste 3 and metal foils 4a are overlapped with each other. Thereafter, these component members are stacked with each other by using a press, and a multilayer body C is thereby formed.
Step (H)
Subsequently, as shown in FIG. 55B, resist films 5 are selectively formed on the metal foils 4a on two faces of the multilayer body C.
Step (I)
Subsequently using the resist films 5 as masks, etching is selectively performed for the metal foils 4a, thereby performing patterning therefor to form wiring films 6a, as shown in FIG. 55C. Thereby, a wiring circuit substrate 7 having four layers of the conductor circuits 6 and 6a are formed.
FIGS. 56A to 56G are used to explain another conventional example of a high-density-mounting wiring circuit substrate. These figures are cross-sectional views illustrating a manufacturing method for the conventional wiring circuit substrate in the order of steps (A) to (G) described below.
Step (A)
For example, as shown in FIG. 56A, a metal foil 10 (having a thickness of, for example, 18 μm) made of a copper material is prepared. Then, on the metal foil 10, conductive protrusions 11 are formed by a printing method via conductive paste (made of a main material such as a silver or copper material) and a metal plate, and then, are heated and cured. The protrusions 11 are thus formed so as to have thicknesses, for example, ranging from 100 to 300 μm.
Step (B)
Subsequently, as shown in FIG. 56B, an insulating adhesive sheet 12 is adhered onto the face on which the protrusions 11 of the aforementioned metal foil 10 are formed. For the adhesive sheet 12, an adhesive sheet having a thickness smaller than the thicknesses of the protrusions 11 is used. Thereby, the top of each of the protrusions 11 protrudes from the surface of the adhesive sheet 12. A multilayer body A is produced that has a configuration in which the protrusions 11 are formed on the metal foil 10 and the adhesive sheet 12 is adhered onto the surface of the metal foil 10 in a state of allowing the top of each the protrusions 11 to protrude therefrom.
Step (C) and Step (D)
Subsequently, as shown FIG. 56C, a metal foil 13 similar to the aforementioned metal foil 10 is arranged over the surface of the adhesive sheet 12, then, as shown in FIG. 56D, the metal foil 13 is overlaid on the adhesive sheet 12 and the protrusions 11 according to a heating-pressing method. Thereby, a multilayer body B is produced.
Step (E)
Subsequently, for example, resist films for which patterning is performed are formed on the metal foils 10 and 13 individually formed on two faces of the multilayer body B. Then, etching is performed for the metal foils 10 and 13 by using the resist films as masks, thereby forming conductor circuits 14 and 15. FIG. 56E shows a configuration where the resist films used as masks are removed after the conductor circuits 14 and 15 are formed.
Step (F)
Subsequently, two multilayer bodies a are prepared. Each of the multilayer body (a) is formed by the same method as that for the multilayer body (A) shown in FIG. 48B. As shown in FIG. 56F, the two multilayer bodies (a) are individually arranged over two faces of the aforementioned multilayer body (B).
Step (G)
The aforementioned multilayer body (B) is sandwiched by the multilayer bodies (a), and the integrated body is pressed from the sides of two faces thereof according to the aforementioned heating-pressing method. Thereby, a wiring circuit substrate 16 as shown in FIG. 56G is produced.
Subsequently, a still another conventional technique will be explained. FIGS. 57A to 57E and 58A to 58D show a production process of still another wiring circuit substrate.
Step (A)
As shown in FIG. 57A, a copper-plated laminated plate 400a is prepared for forming a hole 400b for connection therein by drilling or laser processing. The numeral 400c is an insulating sheet to serve as the base member for the laminated plate 400a, and 400d, 400d are copper foils formed on both sides of the insulating sheet 400c.
Step (B)
Subsequently, as shown in FIG. 57B, a copper plating layer 400e is formed on the entire surface by an electroless plating process and a subsequent electrolytic plating process.
Step (C)
Subsequently, as shown in FIG. 57C, the hole 400b is filled with an insulating resin 400f, such as an epoxy.
Step (D)
Subsequently, as shown in FIG. 57D, both sides of the laminated plate 400a is smoothed by mechanical polishing. Thereafter, another copper plating layer 400g is formed by an electroless plating process and a subsequent electrolytic plating process. Accordingly, the insulating resin 400f filling up the hole 400b is covered by the copper plating layer 400g.
Step (E)
Subsequently, as shown in FIG. 57E, a wiring film 400h is formed by patterning the copper plating layers 400g, 400d, 400e on both sides of the laminated plate 400a. The etching operation is executed by applying a resist film, exposing and developing the same so as to form a mask pattern, and selective etching with the mask pattern used as the mask. After the etching, the resist film is eliminated.
Step (F)
Subsequently, as shown in FIG. 58A, an insulating resin 400i, 400i is coated on both sides of the laminated plate 400a. Thereafter, a hole 400j to be a through hole is formed in the insulating resin 400i by a laser beam. At the time, the residual resin adhered on the surface of the copper foil 400d should be eliminated by using a washing liquid.
Step (G)
Subsequently, as shown in FIG. 58B, a copper plating layer 400k is formed on both sides of the laminated plate 400a by an electroless plating process and an electrolytic plating process.
Step (H)
Subsequently, as shown in FIG. 58C, a circuit 400l is formed by patterning the copper plating layers 400k on both sides of the laminated plate 400a. The etching operation is executed by selective etching with a mask formed by patterning a resist film by exposing and developing used as the mask. Thereafter, the resist film used as the mask is eliminated.
Step (I)
Subsequently, as shown in FIG. 58D, both sides of the laminated plate 400a are covered selectively by a solder resist 400m. Accordingly a wiring circuit substrate 400n is completed.
However, the conventional example shown in FIGS. 54 and 55 arises problems as described the followings. First, the openings 2 in the insulating sheet 1 are filled with the conductive paste 3 made of a main material such as expensive silver material and are used for interlayer connection. This arises a problem of increasing costs. Particularly, since arrangement density of the openings 2 is required to be increased according to an increasing demand for high-density mounting, the increase in costs becomes noticeable so as not to be ignored.
Second, when the conductive paste 3 is filled into the openings 2, the conductive material is adhered to portions other than the openings 2, although the amount thereof is very small. This arises a problem of reducing the insulation resistance, particularly in a high-humidity environment.
Third, when press-overlaying is performed after the openings 2 are formed in the insulating sheet 1, the insulating sheet 1 is forced to horizontally extend. Thereby, positional deviation of the openings 2 occurs. Even by performing correction thereof and making openings, the correction is not effective in the high-density pattern. The positional deviation of the openings 2 causes defective interlayer connection, thereby arising serious problems, which cannot be ignored. Particularly, the problem is critical for the high-density-mounting wiring circuit substrate.
Fourth, the reliability of the connection between the metal foils 4 made of a copper material and the conductive paste 3 is insufficient. The conductive paste 3 filled into the openings 2 removes a solvent component so as to be a semi-cured state. The semi-cured conductive paste shrinks because of removal of the solvent component and the like, thereby reducing the volume of its own. In addition, in most cases, upper and lower faces of the conductive paste 3 become in a concave state. As a result, defective connection is apt to be caused between the metal foils 4, thereby arising a problem of reducing the reliability and the yield.
Subsequently, the conventional example shown in FIGS. 56A to 56G also arises problems as described the followings. First, using the protrusions 11 formed of the conductive paste also arises the problem of increasing costs.
Second, since a screen-printing method is used to form the protrusions 11 with the conductive paste, increase in the thickness thereof is restricted. Therefore, in most cases, screen-printing operations must be repeatedly performed to form the protrusions 11.
When the number of the printing operations is increased, the positional deviation of the protrusions 11 is apt to occur, and deformation of the protrusions 11 is thereby apt to occur. This develops a problem of reducing the reliability of the connections between the protrusions 11 and the metal foils 4. In addition, positioning operation for the screen-printing is very difficult and requires high-level skills, thereby causing a problem of requiring relatively long processing time.
These problems become increasingly apparent in proportion to reduction in the diameter of each of the protrusions 11. For example, for protrusions each having a diameter of 0.3 mm, two printing operations must be performed; and for protrusions each having a diameter of 0.2 mm, four printing operations must be performed. This is heavy work and disturbs improvement in the productivity, remaining problems to be solved for the provision of high-density wiring circuit substrates.
Third, still another problem arises in that heights of the protrusions 11 are likely varied. In specific, in the screen-printing method, since it is difficult to uniform thicknesses of films, heights of the protrusions 11 formed thereby are also likely to be variable. The variation in the thickness likely causes the connection between the metal foil 13 and the protrusions 11 to be defective. This results in arising a problem of reducing the yield and the reliability.
Fourth, in the manufacturing stage, the metal foil 10 basing the wiring circuit substrate is as thin as, for example, 18 μm. Therefore, in the screen-printing sufficient care must be taken to prevent it from being wrinkled, deformed, and bent on the metal foil 13 side. Even a very minor operation problem could reduce the yield. This develops to the problem of increasing costs, which should not be neglected. Conversely, increasing the thickness of the metal foil 10 so as to obtain a strong base also causes a problem of disturbing the conductor circuits to be finely patterned.
One of problems common to the described conventional examples is that there are restrictions in making the high-density arrangement, that is, in the arrangement of fine interlayer connection. In the case of one example, the printing operation is difficult because of the reduction in the diameters of the openings and difficulty in filling the conductive paste into the openings. In the case of another conventional example, the difficulty in the printing operation increases in proportion to the reduction in the diameters in bump printing. Thus, according to the conventional technology, an opening having a diameter smaller than 200 μm cannot be produced.
In addition, since the strength of the connection between the conductive paste and the copper foil is low, an excessively large area is required for the connection.
Next, the wiring circuit substrate shown in FIGS. 57A to 57E and 58A to 58D also involves problems.
A first problem is a poor adhesion property between the surface of the insulating resin 400f for filling the hole 400b and the copper plating layer 400g so as to easily generate adhesion failure.
Particularly at the time of mounting, in the case various members are connected with the area, there is a risk of generating fall-off.
Moreover, in order to solve the problem, the wiring circuit substrate needs to be designed so as not to superimpose the connecting points of the various members and the hole 400b formation area. Therefore, it gives the limitation in designing so as to be a cause for prohibiting a high density of the wiring circuit substrate.
A second problem is deflection of the surface of the copper plating layer 400k in the area with the hole 400j because the copper plating layer 400k is formed in the area with the hole 400j.
Therefore, a wiring layer cannot be formed further on the copper plating layer 400k, and thus a multi-layer structure cannot be provided.
A third problem is the inability of ensuring a sufficient film thickness in the area with the hole 400j because the copper plating layer 400k is formed in the area.
That is, the copper plating layer 400k is formed by an electroless plating process and a subsequent electrolytic plating process. The film formation rate in the electroless plating process is low. Furthermore, the film thickness irregularity can easily be generated in the electrolytic plating process in relation to the electrolytic distribution. Therefore, even in a level difference part for forming the hole 400j, a film is formed with a thin film thickness so that a sufficient film thickness cannot be ensured. This point has prohibited realization of minuteness of the wiring circuit substrate.

Manufacturing method for wiring circuit substrate


A system for providing nitrogen enriched air (NEA) from ambient air uses at least two gas separation membranes that are selectively gas permeable for oxygen and nitrogen. The oxygen/nitrogen selectivity and oxygen permeance of two of the membranes are different such that (1) the selectivity of first membrane is less than the second membrane and the oxygen permeance of first membrane is greater than the second membrane, or (2) the selectivity of first membrane is greater than the second membrane and the oxygen permeance of first membrane is less than the second membrane. The system is very compact, is energy efficient, and highly effective for generating NEA. It is ideally suited for mobile, remote and specialized end use applications, such as automotive vehicles, marine vessels, off-shore platform fuel storage and especially for supplying NEA to blanket ullage of onboard aircraft fuel storage tanks.

Air is a gas mixture comprising about 21 mol % oxygen, about 79 mol % nitrogen and very small amounts of other components such as carbon dioxide, argon and the like. The separation of air to provide oxygen enriched air (OEA) and/or nitrogen enriched air (NEA) is commercially significant. For example, one use of NEA is to provide an inert gas composition in the ullage of mobile fuel tanks, especially aircraft fuel tanks. Such tanks typically contain highly combustible liquid fuels of volatile organic compositions. Raising nitrogen concentration in the ullage sufficiently high can render the vapor above the liquid fuel in a fuel storage tank safely non-combustible. Nitrogen concentration can be effectively raised by displacing any ambient air in the tank with a suitable NEA.
Selectively gas permeable membranes are useful for separating components of gas mixtures. Membrane separation has been used to produce OEA and/or NEA from ambient air. Certain fluorinated composition membranes have been found effective for separating ambient air. A representative example of such a membrane has a nonporous selectively gas permeable layer of perfluorinated dioxole monomer, namely perfluoro-2,2-dimethyl-1,3-dioxole ("PDD") copolymerized with another fluorine containing monomer such as tetrafluoroethylene ("TFE"). Such membranes are available from Compact Membrane Systems, Inc., Newport, Del. An example of a membrane separation process for separating air is disclosed in U.S. Pat. No. 5,051,114. The complete disclosure of all U.S. patents and patent applications identified in the present patent application are hereby incorporated herein by reference.
The separation performance of gas permeable membranes is typically characterized by two principal parameters, namely, the selectivity of the membrane to discriminate between components of a binary feed mixture being separated, and the permeability of the faster permeating component. Usually such membranes exhibit high selectivity with low permeability, or low selectivity with high permeability. In this disclosure reference will be made to permeance. Permeance is permeability divided by the thickness of a membrane.
The trade-off between selectivity and permeance influences the size and operating conditions necessary to achieve desired separation. For example, to obtain highly N2-enriched air at a specified volumetric rate, a very selective membrane can be used. However, the permeance of the fast-migrating component will be relatively low such that production rate is likely slower than desired. This problem can be overcome by increasing the working area of the membrane. In mobile end use applications and particularly for aircraft, size and weight have critical upper limits such that large membrane separators can be unacceptable. Similarly, smaller membranes with higher permeance can be used but enrichment per separation step is relatively low. This problem can be overcome by utilizing a train of separator steps or stages such that enrichment increases in successive steps. The drawback is that many steps or stages and auxiliary equipment, such as compressors with associated power supplies may be needed. The weight and space for the extra equipment and multiple membrane units can be prohibitive.
It is desirable to have a selectively gas permeable membrane separation system for producing NEA from ambient air that is very light weight. It is desired to have a membrane separation system that occupies a small volume and is simple to operate. There is great need for a light weight, compact, energy conserving and reliable membrane separation system suitable for generating NEA to provide inert atmosphere in the ullage of mobile tanks of volatile organic compounds, and especially of onboard fuel tanks of aircraft.

Combination membrane system for producing nitrogen enriched air


In a magnetoresistive effect element using a ferromagnetic tunnel junction having a tunnel barrier layer sandwiched between at least a pair of ferromagnetic layers, a magnetization free layer comprising one of the ferromagnetic layers is composed of a single layer of a material having an amorphous or microcrystal structure or a material layer the main portion of which has an amorphous or microcrystal structure. The magnetoresistive effect element can produce excellent magnetic-resistance characteristics, and a magnetic memory element and a magnetic memory device using the magnetoresistive effect element as a memory element thereof can improve both of write and read characteristics at the same time.

The present invention relates to a magnetoresistive effect element, a magnetic memory element, a magnetic memory device and manufacturing methods thereof, and particularly to a magnetoresistive effect element having stable magnetic characteristics, a magnetic memory element operable as a magnetic nonvolatile memory element, a magnetic memory device composed of the magnetic memory element and manufacturing methods thereof.
As information communication devices, in particular, personal small devices such as personal digital assistants are making great spread, elements such as memories and logics comprising information communication device are requested to have higher performance such as higher integration degree, higher operation speed and lower power consumption. In particular, technologies for making nonvolatile memories become higher in density and larger in storage capacity are progressively increasing their importance as technologies for replacing hard disk and optical disc that cannot be essentially miniaturized because they have movable portions.
As nonvolatile memories, there may be enumerated flash memories using semiconductors and FRAM (Ferro electric Random Access Memory) using ferroelectric material and the like.
However, the flash memory encounters with a drawback that its write speed is as slow as the microsecond order.
On the other hand, it is pointed out that the FRAM has a problem in which it cannot be rewritten so many times.
A magnetic memory device called an MRAM (Magnetic Random Access Memory), (e.g. see "Wang et al., IEEE Trans. Magn. 33 (1977), 4498), receives a remarkable attention as a nonvolatile memory which can overcome these drawbacks.
Since this MRAM is simple in structure, it can easily be integrated at a higher integration degree. Moreover, since it is able to memorize information based upon the rotation of magnetic moment, it can be rewritten so many times. It is also expected that the access time of this magnetic random access memory will be very high, and it was already confirmed that it can be operated at the access time of nanosecond order.
A magnetoresistive effect element for use with this MRAM, in particular, a tunnel magnetoresistive (Tunnel Magnetoresistance) element is fundamentally composed of a lamination layer structure of a ferromagnetic tunnel junction of ferromagnetic layer/tunnel barrier layer/ferromagnetic layer.
This element generates magnetoresistive effect in response to a relative angle between the magnetizations of the two magnetic layers when an external magnetic field is applied to the ferromagnetic layers under the condition in which a constant current is flowing through the ferromagnetic layers. To be concrete, when the magnetization directions of the two magnetic layers are anti-parallel to each other, a resistance value is maximized. When they are parallel to each other, a resistance value is minimized. Function of memory element can be demonstrated by creating the anti-parallel state and the parallel state with application of the external magnetic field when the magnetization direction of one ferromagnetic layer is inverted.
This resistance changing ratio is expressed by the following equation (1) where P1, P2 represent spin polarizabilities of the respective magnetic layers.2P1P2/(1−P1P2)  (1)The resistance changing ratio increases as the respective spin polarizabilities increase. With respect to a relationship between materials for use with ferromagnetic layers and this resistance changing ratio, ferromagnetic chemical elements of Fe group such as Fe, Co, Ni and alloys of three kinds thereof have already been reported so far.
With respect to writing of information in the MRAM, in order to store information in the selected memory element of the magnetic memory element, this magnetic random access memory is composed of a plurality of bit write lines, a plurality of word lines intersecting these bit write lines and TMR elements provided at crossing points between these bit write lines and word write lines as magnetic memory elements. Then, when information is written only in the element located at the selected crossing point of these bit write line and word write line by utilizing an asteroid characteristic (see Japanese laid-open patent application No. 10-116490, for example).
The bit write line and the word write line used in that case are made of conductive thin films such as Cu and Al which are generally used by semiconductor devices. In this case, when information is written in a magnetic memory element of which the inverted magnetic field for generating the above-mentioned inversion of the magnetization is 40 [Oe], for example, by the bit write line and the word write line, the bit write line and the word write line being 0.35 μm in width, a current of approximately 10 mA was required. In this case, assuming that the thickness of the write line be the same as the line width, then a current density required at that time becomes 8.0×10−6 A/cm2. There is then a risk that breaking of wire will be caused by electromigration.
Accordingly, from a standpoint of the occurrence of electromigration and further in view of a problem of heat generated by the recording current and from a standpoint of decreasing a power consumption, this recording current has to be decreased.
As a means for decreasing the recording current, there is enumerated a method of decreasing an inverted magnetic field of a TMR element, i.e., coercive force.
The coercive force of this TMR element is determined based upon the size, shape of the element, the film arrangement and the selection of the materials. However, although it is desired that the size of the element should be miniaturized for the purpose of increasing a recording density of the MRAM, for example, the coercive force of the element tends to increase due to the miniaturization of the element. Therefore, the decrease of the coercive force should be attained from the material standpoint.
If the magnetic characteristic of the magnetic memory element is dispersed at every element and the magnetic characteristic is dispersed when the same element is used repeatedly, the selective writing using the asteroid characteristic becomes difficult.
Therefore, the magnetic memory element is requested to have a magnetic characteristic by which an ideal asteroid curve can be drawn. In order to draw the ideal asteroid curve, an R—H (resistance-magnetic field) curve obtained when TMR is measured should not have noises such as a Barkhausen noise, a rectangle property of a waveform should be excellent, the magnetization state should be stable and the dispersion of the coercive force Hc should be small.
Information may be read out from the magnetic memory element as follows. When magnetic moments of one ferromagnetic layer and the other ferromagnetic layer across the tunnel barrier layer are anti-parallel to each other and a resistance value is high, this state is referred to as a "1", for example. Conversely, when the respective magnetic moments are parallel to each other and a resistance value is low, this state is referred to as a "0". Then, information is read out from the magnetic memory element based upon a difference current obtained at a constant bias voltage or a difference voltage obtained at a constant bias current in these "1" and "0" states.
Accordingly, when resistance dispersions between the elements are identical to each other, a higher TMR ratio (Rmax−Rmin) Rmin where a resistance value Rmin represents the low resistance state and a resistance value Rmax represents the high resistance state) is advantageous and hence a magnetic memory device that can operate at a high speed, having a high integration degree and having a low error rate can be realized.
A magnetic memory element having a fundamental structure of ferromagnetic layer/tunnel barrier layer/ferromagnetic layer has a bias voltage dependence of TMR ratio., and it is known that the TMR ratio decreases as the bias voltage increases.
When information is read out from the element based upon the difference current or the difference voltage, it is known that the TMR ratio takes the maximum value of the read signal at a voltage (Vh) which decreases by half depending upon the bias voltage dependence. Accordingly, a smaller bias voltage dependence is effective for decreasing read error in the MRAM.
Therefore, the TMR element for use with the MRAM should satisfy the above-mentioned write characteristic requirements and the above-mentioned read characteristic requirements at the same time.
However, when the magnetization free layer is generally made of a magnetic material composed of only ferromagnetic transition metal chemical elements of Co, Fe, Ni, if the alloy compositions by which the spin polarizabilities shown by P1 and P2 in the aforementioned equation (1) are increased are selected, then the coercive force Hc tends to increase.
For example, when the magnetization free layer is made of Co75Fe25 (atomic %) alloy and the like, although a TMR ratio having large spin polarizabilities and which is greater than 40% can be maintained, it is unavoidable that the coercive force also increases. But instead, when the magnetization free layer is made of an Ni80Fe20 (atomic %) alloy which is referred to as a "permalloy" and the like, although the spin polarizabilities are small as compared with the case in which the magnetization free layer is made of the Co75Fe25 (atomic %) alloy so that the TMR ratio is lowered up to about 33%.
Further, when the magnetization free layer is made of a Co90 Fe10 (atomic %) alloy, although a TMR ratio of about 37% can be obtained and its coercive force can become an intermediate value between the above-mentioned Co75Fe25 (atomic %) alloy and Ni89Fe20 (atomic %) alloy, this magnetization free layer is inferior in rectangle property of an R—H loop and an asteroid characteristic by which information can be written in the element cannot be obtained.

Magnetoresistive effect element, magnetic memory element magnetic memory device and manufacturing methods thereof


A semiconductor device and a method of making a semiconductor device. A damascene metal layer (16) is formed in an insulating dielectric layer (12), which is in direct electrical communication with a substrate (10). A layer of a passive element, such as first capacitor electrode layer (20) is disposed on metal layer (16) and preferably is offset relative to metal layer (16) to allow a direct electrical interconnect through a via (36) to metal layer (16). In one embodiment a capacitor and a resistor are formed as passive elements in the device. In another embodiment, the passive element includes at least one resistor (28) and optionally a second resistor (32). In yet another embodiment, metal layer (16) is a damascene copper layer.

The present invention is directed to a semiconductor device and method for forming a semiconductor device, and particularly, a semiconductor device, including at least one passive element, adapted for use in wireless communication systems.
Many electronic devices currently suffer design and resulting performance limitations in view of the state of semiconductor device fabrication technology. Wireless communication systems, for example, generally contain relatively few semiconductor chips, but several hundred passive elements. As efforts continue to enhance form factor and power reduction, and to improve performance and functionality at frequencies on the order of 109 Hz or higher, it has become desirable to integrate passive elements into separate chips or modules and onto active substrates (such as silicon-containing substrates).
A variety of on-chip capacitor and resistor technologies currently exist, examples of which include double-poly, gate-oxide or junction capacitors or diffused silicon or poly silicon resistors. Many applications would benefit from an improvement in performance characteristics resulting from these technologies. For example, improvement is sought in the areas of reducing parasitic capacitance, improving voltage linearity, reducing electrode series resistance or reducing 1/f noise. It is also desired that resulting devices be integrated into the backend of an active substrate (e.g., Si-chip), heretofore not accomplished using existing technology.

Method of making semiconductor device having passive elements including forming capacitor electrode and resistor from same layer of material


The disclosure describes asymmetric turning films (ATFs) that may be used in conjunction with multiple light sources in a liquid crystal display assembly to provide multiple different characteristic output distributions of light. In some examples, the ATFs include a structured surface defining a plurality of microstructures having two or more faces with each face configured to reflect light in different directions. The microstructure may define a microstructure axis and an angle gradient characterizing the rotation of the microstructure axis across the structured surface of the ATF.

Turning films are used in many display and lighting applications to change the angular distribution of light. Turning films generally have features which operate by refracting and/or reflecting light. Turning films may be used in conjunction with light sources and liquid crystal displays to provide a desired light output.
Temporal multiplexing in display applications generally refers to providing non-continuous series of images through the same backlight architecture at a rate faster than the perceptible limit for human observation. The brain perceives the separate images as combined singular image.

Multiplexing backlight with asymmetric turning film


An in-line production apparatus and a method for composition control of copper indium gallium diselenide (CIGS) solar cells fabricated by a co-evaporation deposition process. The deposition conditions are so that a deposited Cu-excessive overall composition is transformed into to a Cu-deficient overall composition, the final CIGS film. Substrates with a molybdenum layer move through the process chamber with constant speed. The transition from copper rich to copper deficient composition on a substrate is detected by using sensors which detect a physical parameter related to the transition. A preferred embodiment sensors are provided that detect the composition of elements in the deposited layer. A controller connected to the sensors adjusts the fluxes from the evaporant sources in order provide a CIGS layer with uniform composition and thickness over the width of the substrate.

Solar cells provide a means to produce electric power with minimal environmental impact because it is a renewable technology. In order to become a commercial success the solar cells need to be efficient, to have low cost, to be durable, and not add other environmental problems.
Today's dominant solar cell technology is based on crystalline silicon. It fulfils many of the requirements mentioned above but can not be produced at such low cost that electricity generation in large scale is cost effective. It also requires relatively large amount of energy in the production, which is an environmental disadvantage.
Solar cells based on thin film technologies have been developed. They offer a potential of substantial cost reductions but have, in general, lower conversion efficiencies and less good durability. A very promising thin film solar cell technology is based on the semiconductor Cu(In,Ga)Se2 (CIGS) which has demonstrated high efficiencies (16.6% in small prototype modules) and durability in operation.

Method and apparatus for in-line process control of the cigs process


The present disclosure is directed to methods of preparing prostaglandin J natural products by stereoretentive metatheses reactions and intermediates used in the synthesis of these natural products, including the use of intermediates of Formula (I-A), where R1 is defined in the specification

Δ12-prostaglandin J natural products (1-4, FIG. 1) features a unique cross-conjugated dienone motif and appealing anti-cancer activity. Δ12-PGJs are secondary metabolites of fatty acids (ARA or EPA), isolated from cell culture. For example, ω-6 arachidonic acid (ARA) is converted by cyclooxygenase (COX; also known as PGH synthase) to PGH2. This pivotal intermediate is converted enzymatically to a variety of biologically active prostaglandins, including PGD2, PGE2, PGF2α, and PGI2. PGD2 can be spontaneously converted to Δ12-PGJ2 and 15d-PGJ2 via a nonenzymatic process. A similar biosynthetic pathway is known to account for the formation of Δ12-PGJ3 and 15d-PGJ3 from ω-3 eicosapentaenoic acid (EPA). Among the Δ12-prostaglandin J family, 15d-PGJ2 is the most well-studied and it is reported to be an endogenous ligand for peroxisome proliferator activated receptor-γ (PPAR-γ), which recognizes PPAR-response elements (PPRE) in the promoter region of target genes to stimulate or suppress DNA transcription. This pathway is responsible for the antineoplastic, anti-inflammatory, antiviral, and antiproliferative properties of 15d-PGJ2. Recently, it was reported that selenium supplementation upregulated the ARA metabolism to favor the production of CyPGs, which resulted in an amplification of PPAR-γ signaling, inhibiting chronic myeloid leukemia (CML) progression. 15d-PGJ2 features a unique cross-conjugated dienone motif, and this highly electrophilic structure accounts for the modifications of many proteins by covalent interactions. For example, crystallographic data show that PPAR-γ is covalently modified by 15d-PGJ2 via a Michael addition at the C9 or C13 position with the cysteine C285 residue.
Synthetic efforts toward Δ12-prostaglandin J compounds began in 2003, with a number of syntheses of Δ12-PGJ2 (see FIG. 1) and 15d-PGJ2 (see FIG. 1) reported through various approaches. See, e.g., (a) Bickley, J. F., et al., Synlett 2003, 1170-1174; (b) Brummond, K. M, et al., Org. Lett. 2004, 6, 149-152; (c) Acharya, H. P., et al., Tetrahedron Lett. 2004, 45, 1199-1202; (d) Acharya, H. P., et al., Tetrahedron 2006, 62, 3329-3343; (e) Kim, N.-J., et al., J. Org. Chem. 2010, 75, 7458-7460; (f) Egger, J., et al., Org. Lett. 2015, 17, 4340-4343; (g) Nicolaou, K. C. et al, J. Org. Chem. 2019, 84, 365-378. Total synthesis of Δ12-PGJ3 (see FIG. 1) were reported by Nicolaou and co-workers (see, e.g., (a) Nicolaou, K. C., et al., Angew. Chem., Int. Ed. 2014, 53, 10443-10447; (b) Nicolaou, K. C., Chem.-Eur. J. 2016, 22, 8559-8570 and more recently by the Aggarwal group (see, e.g., Pelšs, A., et al.. Chem.-Eur. J. 2018, 24, 9542-9545.).
Recently, Grubbs and Stoltz labs developed the shortest synthesis of all four of the Δ12-PGJ natural products by using stereoretentive metathesis. See WO2019222244 and Li, Jiaming, et al., "Concise Syntheses of Δ12-Prostaglandin J Natural Products via Stereoretentive Metathesis," J. Amer. Chem. Soc. 2019, 141, 154-158, each of which are incorporated by reference for all their teachings with respect to the methods and strategies for preparing prostaglandins and their intermediates. For example, tandem conjugate addition, aldol reaction and dehydration was performed to obtain 9, (references to compounds in this section are directed to those in FIG. 2), which was subjected to the standard one-pot stereoretentive homodimerization/cross-metathesis conditions. 10 was obtained in excellent yield (93% yield, FIG. 2) with high Z-selectivity (>99% Z). Finally, Ley oxidation of 10 gave 15-deoxy-Δ12,14-prostaglandin J2 (FIG. 2) in 68% yield.

However, intermediate 9 was obtained with a substantial loss in enantiopurity (88% ee) from enantiopure starting material 1 (>99% ee). The metathesis product 10 was obtained without significant erosion of enantiopurity (87% ee), which indicated that stereoretentive metathesis with the Z-selective ruthenium catalyst (designated "Ru-4," vida infra) retained the stereochemistry of the C8 stereocenter. Since the enantioenriched product is highly desirable in the downstream applications, such as in pharmaceutical industry, the inventors embarked on a study aimed to improve the enantioselectivity as well as the overall yield of intermediate 9.
The present disclosure sets forth the results of these exhaustive investigation that address at least some of these issues, as relevant to this and other such intermediates.

Total synthesis of prostaglandin J natural products and their intermediates


A charge-transporting layer includes a matrix-domain structure. The domain contains a polyester resin A. The matrix contains a charge-transporting substance and at least one of a polyester resin C and a polycarbonate resin D.

1. Field of the Invention
The present invention relates to an electrophotographic photosensitive member, and a process cartridge and an electrophotographic apparatus each having an electrophotographic photosensitive member.
2. Description of the Related Art
An electrophotographic photosensitive member which contains an organic photoconducting material is predominantly used as the electrophotographic photosensitive member to be installed on a process cartridge or an electrophotographic apparatus. In general, an electrophotographic photosensitive member includes a support and a photosensitive layer which contains an organic photoconducting material on the support. The photosensitive layer is typically of a lamination type (sequential layer type), formed of a charge-generating layer and a charge-transporting layer laminated in this order from the support side.
In an electrophotographic process, the surface of an electrophotographic photosensitive member comes in contact with various materials (hereinafter referred to as "a contact member") such as developer, a charging member, a cleaning blade, paper, and a transfer member. Examples of required characteristics for an electrophotographic photosensitive member therefore include reducibility of image deterioration due to contact stress with a contact member. In association with recent improvement in durability of an electrophotographic photosensitive member, further improvement is required in sustained effect of reduction in image deterioration due to the contact stress and in potential stability (reduction in potential variation) for repeating use.
Regarding sustained contact stress relaxation effect and potential stability for repeating use of an electrophotographic photosensitive member, a method for forming a matrix-domain structure in a surface layer using a siloxane resin having a siloxane structure integrated into a molecular chain is disclosed in International Publication No. WO2010/008095. According to the method, the use of a polyester resin having a specific siloxane structure allows for both of the sustained contact stress relaxation effect and the potential stability for repeating use of an electrophotographic photosensitive member.
The electrophotographic photosensitive member disclosed in International Publication No. WO2010/008095 achieves both of the sustained contact stress relaxation effect and the potential stability for repeating use.
However, the present inventors have found requirements for further improvement in the image deterioration caused by a photo memory due to a potential difference between a portion irradiated with light and a portion not irradiated with light.

Electrophotographic photosensitive member, process cartridge and electrophotographic apparatus


A memory device of the present invention allows high integration, improved operational speed, larger capacitance, improved isolation and/or reduced leakage current. The memory device includes a plurality of transistors parallel to each other and formed above a substrate. A bit line is perpendicular to each of the plurality of transistors, and is coupled to the transistors. A predetermined portion of each transistor is a storage node for a capacitor, and a plate surrounds the predetermined portion through a dielectric film.

FIGS. 1 and 2 are a cross-sectional view and an equivalent circuit diagram, respectively, of a conventional DRAM (Dynamic Random Access Memory). A memory cell includes a p well 2 formed in a predetermined part of a silicon substrate 1 manufactured through a p-type impurity doping process, and a pair of field oxide films 4, having doping layers 3 therebeneath, are formed at a predetermined distance therebetween to distinguish an element isolation region from an active region. A plurality of word lines 6' are connected to switching transistors and a transfer transistor gate electrode 6 formed at a predetermined part of the active region and the element isolation region on the substrate.
A capacitor includes a storage node electrode 7, a dielectric film 8, and a plate electrode 9, being combined with the switching transistors having a lower insulating film 10 therebetween. A contact hole is formed through insulating films formed on the switching transistors to expose a region of the switching transistors. A bit line 11 is formed on the upper insulating film 10' having the contact hole to be coupled to the exposed region.
FIG. 2 shows the equivalent circuit diagram of the DRAM cell. When a data signal to be stored is applied to a corresponding bit line 11 while a voltage exceeding the threshold voltage of the transfer transistor gate electrode 6 is applied to the corresponding word line 6', the transistor is turned on. The data is stored as a charge in the capacitor of the cell. After storage, the voltage of the word line 6' is lowered to switch off the transfer transistor and the data signal charge does not escape. When the stored data signal is read, a voltage is applied to the corresponding word line 6' again and the charge accumulated in the cell capacitor (a) is transmitted through the bit line 11 to a sense amplifier connected thereto. Through the abovementioned course, writing and reading operations are performed.
The conventional DRAM cell is disadvantageous since the field oxide film 4 is formed having the P well 2 and the element isolation region on the silicon substrate 1 (for example, a field insulation doping layer), isolation of the elements is difficult. Further, because the switching transistor is formed only on the silicon substrate, a cell array takes up a larger area. Only one surface of the storage node electrode 7 serves as a capacitor (a), and the capacity of the capacitor per cell area is limited. The operational speed is also delayed in accordance with a contact resistance between the switching transistor and a connection (b shown in FIG. 1) for the storage node electrode 7. Moreover, data may be lost by a leakage current generated at the contact region of the storage node electrode 7.

Memory device and fabrication method thereof


An improved mixing and dispensing apparatus for reconstituting and remixing reconstituted juice concentrate includes a container, a spout, a cap with a skirt and a mixing element with a shaft having a handle at one end and a mixing head at the other end. The mixing head is adapted to displace the liquid substantially radially and non-circularly and only moderately axially relative to the shaft as the shaft is reciprocally displaced axially relative to the cap. The container has indicia for indicating the quantity of liquid contained therein. The container generally has a non-circularly shaped cavity which, in cooperation with the mixing head, prevents rotational displacement of the mixing head relative to the cavity. Alternatively, a shaft opening in the cap and a cross-sectional profile of the shaft cooperatively prevent relative rotational therebetween. The skirt has pour openings which may be selectively and separately spaced adjacently to the spout such that ice contained in the liquid may be poured from, or restricted to, the container or non-adjacently to the spout such that ambient atmospheric oxidation is minimal. An upstop limits initial displacement of the mixing head to total emersion in the liquid. The upstop is adjustable for varying initial quantities of the liquid.

For those with discerning taste, it is well known that juice concentrate reconstituted by stirring with a spoon tastes substantially better than that reconstituted by using a blender or by shaking a container containing the juice. The loss in taste probably results from the blending of substantial quantities of air into the juice because of the turbulent and swirling action of the blender or shaker. To the contrary, the improved taste when using a spoon probably results from the avoidance of significant inclusion of ambient atmospheric air into the mixture because of substantially reduce turbulence. However, stirring with a spoon generally requires a circular displacement of the mixture and breaking the free surface of the mixture with a handle of the spoon, which also introduces some atmospheric air into the mixture. In addition, the latter not only produces a drippy spoon when the juice concentrate is reconstituted, but also produces another drippy spoon each time the juice is re-stirred prior to dispensing thereof.
Thus, what is needed is an apparatus which provides a mixer for reconstituting the juice concentrate while substantially minimizing inclusion of ambient atmospheric air in the juice without the use of another appliance or utensil such as a spoon and which, in addition, provides a container for subsequently remixing the reconstituted juice concentrate as needed again without the use of another utensil.

Juice concentrate mixing and dispensing apparatus


A developing device including a developing roller mounted in a developing chamber is provided. In the developing device, the developing roller is partially exposed to an environment outside the developing chamber through an opening portion of the developing chamber, an air inlet is provided between an upstream boundary of the opening portion in a rotational direction of the developing roller and an outercircumference of the developing roller, wherein air may pass into the developing chamber through the air inlet, and an air outlet may be formed near the upstream boundary of the opening portion and communicatively connected to the developing chamber so as to discharge the air in the developing chamber. The air outlet is located outside an effective image area in a length direction of the developing roller.

An image forming apparatus using an electrophotographic method supplies toner to an electrostatic latent image formed on a photosensitive body to form a toner image, transfers the toner image onto a recording medium, and fixes the transferred toner image on the recording medium so as to print an image on the recording medium. A developing device accommodates toner, and supplies the toner to the electrostatic latent image formed on the photosensitive body to form a visible toner image on the photosensitive body.
A developing device includes a developing chamber and a developing roller supplying toner, accommodated in the developing chamber, to a photosensitive body. As the developing roller is rotated, air flows into the developing chamber which increases a pressure therein. When an internal pressure in the developing chamber has reached a predetermined level, the air reflows into an air inlet, causing the air to be discharged to the outside through the air inlet. In such a case, the toner in the developing chamber may also be discharged with the air, which may result in scattering of the toner to the outside of the developing device. The scattered toner may contaminate the photosensitive body and degrade a printing image quality. In addition, the scattered toner may contaminate an inner portion of an image forming apparatus.

Hewlett-Packard Development Company, L.P.


A microfluidic system employs a microchannel and a gravity driven pump comprising horizontally oriented fluid supply reservoirs which supplies fluid to the microchannel at a substantially constant rate. The device is useful for numerous microfluidic applications, for example in the culture and/or treatment of biological systems under constant flow-induced stress, cell-size sorting, motile sperm sorting, or embryo culture.

1. Field of the Invention
The present invention pertains to gravity driven pumps for microfluidic applications, and to microfluidic devices employing such pumps.
2. Background Art
Microfluidic devices are steadily supplanting their macroscale counterparts in numerous applications, particularly in biological and pharmaceutical research. Such devices often require one or more pumps to propel fluid through microchannels. Current methods may employ mechanical pumps such as syringe-type pumps and micromechanical pumps, and non-mechanical pumps such as electrohydrodynamic pumps, electro-osmotic flow pumps, electrowetting pumps, and thermocapillary pumps.
All these pumping systems have drawbacks associated with them. For example, a steady flow rate is difficult to achieve. Moreover, mechanical pumps require an electrical power source, as do pumps which operate based on electrical properties. Most of these pumps are costly and inconvenient to integrate with other microscale devices, and often have slow response times. Electro-osmotic flow pumps have a flow profile which is pH dependent, and which produce stable flow only over a limited pH range. Recently, a thermocapillary pump has been developed. However, this pump requires complex electronic control circuitry and creates heat transfer issues.
The use of gravity-driven flow in microfluidic applications has been attempted. However, conventional reservoirs produce a decrease in hydrostatic pressure as the liquid level in the reservoir drops. This decreasing pressure difference leads to decreased flow rates with respect to time.
It would be desirable to provide a microfluidic system including a microfluidic pump which is simple, economical to produce, and preferably disposable, which can provide a relatively constant and optionally adjustable flow rate, without the necessity for an external power source.

Microfluidic gravity pump with constant flow rate


A stretchable stitch-bonded nonwoven fabric is disclosed herein. The fabric includes a nonwoven substrate having basis weight in the range from about 15 to about 150 g/m2, and density in the range from about 0.02 to about 0.12 g/cm3. The nonwoven substrate is bonded with a binder applied to the outer surfaces of the substrate in a liquid form in a sufficiently uniform manner so that no areas greater than the spaces between stitch insertion points are devoid of binder. The binder constitutes from about 2% to about 25% of the total weight of the sum of binder and nonwoven substrate weight. The substrate is stitch-bonded with yarns arranged in a stitch pattern that allows the stitch-bonded fabric to be stretched in at least one direction by a factor of about 2.5 to about 5.0 without forming local ruptures therein, and wherein the stitch-bonded nonwoven fabric can be washed and dried at least twenty times.

Processes are known for making stretchable stitch-bonded nonwoven fabrics by multi-needle stitching of a fibrous layer with elastic yarn. Earlier patents disclosing such processes include U.S. Pat. No. 4,704,321, which describes stitching and contracting non-bonded plexifilamentary polyethylene sheets, U.S. Pat. No. 4,876,128, which discloses stitching and contracting bonded fibrous layers, and U.S. Pat. No. 4,773,238, which describes stitching a substantially non-bonded web and then contracting the stitched fabric to less than half its original area, among others.
To produce a highly stretchable stitch-bonded fabric by these known processes generally required that the stitched fabric be allowed to contract or gather extensively after the stitching step. The contraction was caused by the retractive power of the elastic stitching yarns. Stitch-bonding with elastic yarns usually was not performed with accurately controlled tensions on (a) the fibrous substrates fed to the stitch-bonding machine, (b) on the elastic yarns fed to the stitching needles and/or (c) on the stitched fabrics leaving the machine. Generally, the stitch-bonding machines were operated with high tensions on each of these components. In addition, the elastic yarns were subjected to increased tension by the action of the stitching needles of the stitch-bonding machine. Accordingly, the yarns arrived at the stitching needles with high elongations and were inserted into the fibrous layer with very little residual stretch remaining in the yarns. The elongation of the stitched yarn usually was quite close to its break elongation.
For example, as described in the '238 patent, the elastic yarns were fed to the stitch-bonding machine with an elongation of 100 to 250%, and then further stretched by the action of the stitching needles. The high elongation and low residual stretch of the elastic yarns in the stitched fabric were evident from the large contraction of the stitch-bonded fabric as it exited the stitching machine, despite a high wind-up tension applied to the exiting fabric, and from the inability of the stitched and contracted fabrics to be stretched much beyond its original stitched dimensions. It was only after the contraction that the fabrics could be stretched significantly.
U.S. Pat. No. 4,998,421 discloses a process for making an elastic stitch-bonded fabric, which does not require large contraction of the fabric after stitching in order to achieve stretchability. The non-woven substrates described in the '421 patent include "substantially nonbonded" webs wherein "the fibers are not generally bonded to each other by chemical or thermal action". To improve durability (e.g., wash resistance, surface stability and abrasion resistance), such substrates are needle-punched or point-bonded or line-bonded. While such actions improve the durability of the substrates, they also reduce the stretchability of the substrates.
U.S. Pat. No. 5,879,779 also discloses stitch-bonded fabrics utilizing "lightly bonded or unbonded nonwovens" stitched with stretchable "POY" yarns. The fabrics can be stretched to a limited degree beyond their original "as-stitched" dimensions making them "moldable." They can also be shrunk, and then stretched. Only point bonded and entangled/spunlaced non-woven substrates are given as examples in the '779 patent. Extensive bonding of the fibers to each other, and extensive distribution of binder among the fibers and onto the surfaces of the fibers are avoided by using liquid chemical binders, sheath binders over high melting fiber cores and the like to prevent over bonding and the resulting loss of stretchability.
There remains a need in the art for stretchable stitch-bonded nonwoven fabrics that utilize the stretchability of the nonwoven substrate and do not require significant contraction of the fabrics after the stitch-bonding process before the fabrics achieve stretchability.

Stitch-bonded fabrics utilizing stretchable substrates


The invention proposes a valve train of an internal combustion engine comprising a cam (1) and a directly driven cam follower (2), such as a roller tappet. This valve train is additionally designed for effecting an internal exhaust gas recirculation at an exhaust valve. A housing (4) of the cam follower (2) comprises two relatively displaceable elements (8, 9). The cam (1) is configured as a high lift cam (1a) for the inner element (8), and at least one low lift cam (1b) configured out-of-phase to the high lift cam (1a) is provided for the outer element (9). When it is desired to carry out an internal exhaust gas recirculation, the two elements (8, 9) are coupled to each other by a coupling element (10), so that, at the end of the base circle of the high lift cam (1a), the low lift cam (1b) protruding thereinto enables a slight post-opening of the gas exchange valve concerned and, thus also, an exhaust gas recirculation.

Valve trains of the pre-cited type are sufficiently well-known in the technical field and need no further detailed description here. An internal exhaust gas recirculation within narrow limits takes place due to valve overlap. For example, the quantity of exhaust gas returned to the combustion chamber by the exhaust gas system is determined by the point of time of closing of the exhaust valve. This can lead to advantages with regard to consumption and emission. Besides this, a late point of time of closing of the exhaust valve reduces the induction work because less throttling is required for load regulation.
It can be said, in general, that the quantities of exhaust gas recirculated due to design-related valve overlaps in engines without a variable valve control are relatively small.
The technical world is further familiar with solutions in which an external exhaust gas recirculation is used. In this case, exhaust gas components are extracted at the exhaust manifold and returned to the intake manifold through complex pipe systems. In addition to the pipes, it is also necessary to provide return valves for the exhaust gas in these solutions.

Valve train of an internal combustion engine


An auxiliary web feeder attachment for selective alphanumeric printers includes a convex flexible flange or base which fits under and is held in position by the printer. A hollow cylinder attached to the base connects one end of a flexible steel conduit or gooseneck arm. A support shaft is attached to the other end of the flexible gooseneck arm for supporting a standard 2.5 inch wide roll of calculator or adding machine web paper. The support shaft includes a fixed first flange on one end and a removable cap having a second flange on the opposite end, the removable cap having a second flange on the opposite end, the removable flange being retained on the shaft by friction. The auxiliary web feeder attachment enables the roll of paper to be selectively moved into position to feed the web of paper to the printer when it is desired to print small messages without a substantial waste of paper. A paper clip having toothed bifurcated legs biased toward each other to grip an end of the web paper extending from the roll when the roll is moved out of web feeding position is mounted by a C-clamp on the auxiliary web feeder attachment.

1. FIELD OF THE INVENTION
The present invention relates to a web feeder attachment for a selective, alphanumeric printer such as a dot matrix printer, daisy wheel printer, typewriter and the like. More specifically, this invention relates to a flexible holder for supporting a roll of standard 2.5 inch adding machine roll paper, whereby the roll paper may be selectively positioned for printing thereon when desired, and easily moved out of the way at other times.
Many selective printers are connected to and controlled by personal computers, and normally print information on fan-folded web paper perforated to provide tear-off sheets that are 81/2 by 11 inches in size. Many times, however, the user may print reminder notes of only a few lines, such as an address, telephone numbers, "to-do" lists, recipes, instructions to secretaries, case citations, etc., or use the personal computer as a desk calculator, or as a label printer, resulting in a tremendous waste of paper when printing on an 81/2 by 11 inch sheet of paper. This invention saves paper by enabling the easy substitution of adding machine paper for the larger size paper.
2. DESCRIPTION OF THE RELATED PRIOR ART
Structure for supporting web-paper supply rolls on a selective alphanumeric printer is well known in the prior art. U.S. Pat. No. 766,804 issued Aug. 9, 1904 to Charles J. Bellamy discloses a typewriter attachment for mounting a roll of paper on a typewriter comprising a frame with recesses for receiving the ends of a paper roll shaft, the frame having depending pegs which are inserted into hollow posts provided on the typewriter carriage, whereby the frame may be quickly removed.
U.S. Pat. No. 858,597 issued Jul. 2, 1907 to Hiram j. Halle discloses a frame permanently attached to a typewriter carriage for supporting a roll of paper.
U.S. Pat. No. 1,124,378 issued Jan. 12, 1915 to Clio B. Yaw discloses a frame secured to a fixed portion of a combined typewriter, which frame supports a roll of adding machine paper to be used by the combined typewriter and adding machine.
U.S. Pat. No. 3,986,594 issued Oct. 19, 1976 to Nicholas Kondur, Jr. discloses a fixed frame for supporting a roll of paper for use with a matrix print head mounted on a shiftable carriage.
As will be seen, none of the above cited patents, taken alone or in combination, disclose the invention described below and in the appended claims.

Auxiliary web feeder attachment for printer


The wheel and tire dolly apparatus provides a compact, mobile support for holding a wheel and tire at an adjustably chosen height within the cradle with backplate. The cradle can be pivoted with relation to the triangular base with omnidirectional casters. Two pivot arm casters optionally pivot outward to provide a wider base support. A spring loaded stop holds the wheel and tire within the cradle. The foot pedal controls raising and releasing of the upright within the vertical sleeve, the upright supporting the cradle.

A problem inherent in vehicle maintenance involves the vertical lift and lowering of wheel/tire combinations, either to remove or install a wheel and tire, or to service related and proximal vehicle parts. Lifting a wheel and tire is difficult, because of bulk and weight, with many wheel/tire combinations easily exceeding an individual's ability to lift them. Even if capable, a worker is prone to injury. While various devices have been proposed to alleviate the problems associated with handling wheels and tires, none offer all of the desirable advantages most needed in providing a tool for such which is compact, inexpensively produced and sold, easily operated, and quickly height adjustable. More than one device previously offered is quite complex. Complexity often results in a user simply not using the device, due either to a lack of competency or to the time involved in use. And, complex devices often negate purchase due to cost of production and sale. Some devices previously proposed are also quite bulky, thereby restricting use.
Too many wheels, too great a base dimension, and large overall size deter use in crowded work spaces, and offer sometimes even greater difficulty in storage when not in use. Some such devices require extended legs because the tire and device must have such to support the tire and/or wheel and negate toppling. These prior proposed devices also do not allow a tire or wheel to be pivotally positioned upon the device. Some devices require external pneumatic pressure for operation, a less than desirable trait in various work environments. Further, the devices previously proposed do not lend themselves to use in multiples. Rotating tires, for example, requires that either two or four tires, on a typical car, require removal, transfer to another hub, and reinstallation. Therefore, multiple devices are needed. A bulky, costly, or complex device does not encourage multiple purchases and use. Further, a bulky device does not always allow access to the vehicle's hubs, as jack stands, lifts, equipment, and a host of other items may simply bar proximity of a bulky device. What is needed is an apparatus for supporting a tire, wheel, or combination which is inexpensively produced and sold, so that multiple units may be employed. The apparatus should be operable without instruction. The ideal apparatus should be sufficiently compact to allow full access to an area proximal to the wheel and tire, so that full unencumbered use is possible. The ideal apparatus should provide for foot control in lifting and lowering, so that hands can be used for other tasks. The apparatus should also be compact to provide for storage in limited space areas. The apparatus should provide rotation of the supported wheel and tire.The apparatus should be compactly sized to provide for confined space use, to provide for storage, and to provide for use in multiples, such as in rotating 4 or even more tires. The apparatus should further provide for holding a supported wheel and tire without the need for a user to aid in preventing the wheel and tire from falling. The present apparatus provides these advantages.


A marine engine has a crankshaft that rotates about a crankshaft axis; a crankcase supporting the crankshaft, the crankcase being made primarily of a first material; and a cover on the crankcase. The cover includes a heat exchanger having an inner plate facing an interior of the crankcase, and the inner plate is located such that rotation of the crankshaft causes lubricant in the crankcase to impinge upon the inner plate. The cover also includes a frame holding the heat exchanger and isolating the heat exchanger from direct contact with the crankcase. At least a portion of the frame is made of a second material that is more compliant than the first material.

U.S. Pat. No. 7,198,019 discloses a lubricating system for a marine engine that provides a lubrication deflector which extends from the cylinder block of the engine toward rotating surfaces of a crankshaft and/or connecting rod. A lubrication passage is provided as an integral part of a cylinder block of the marine engine to direct a flow of liquid lubricant away from the lubrication deflectors and downwardly toward a lubrication reservoir, or sump.
U.S. Pat. No. 8,696,394 discloses a marine propulsion system comprising an internal combustion engine, a cooling circuit carrying cooling fluid that cools the internal combustion engine, a sump holding oil that drains from the internal combustion engine, and a heat exchanger receiving the cooling fluid. The oil that drains from the internal combustion engine to the sump passes through and is cooled by the heat exchanger.
U.S. Pat. No. 9,457,881 discloses an outboard marine engine having an engine block; a crankcase on the engine block; a crankshaft disposed in the crankcase for rotation about a crankshaft axis; a cover on the crankcase; a bedplate disposed between the engine block and the cover, the bedplate having a plurality of bearings for supporting rotation of the crankshaft; and a cooling water jacket that extends parallel to the crankshaft axis along a radially outer portion of the plurality of bearings. The cooling water jacket carries cooling water for cooling the plurality of bearings and at least one oil drain-back area is located adjacent to the cooling water jacket. The at least one oil drain-back area drains oil from the crankcase.
U.S. Pat. No. 10,344,639 discloses a marine engine having a crankcase having a crankshaft that rotates about a vertical crankshaft axis; a cover on the crankcase; and a cooling member disposed in the crankcase. The cooling member has an inner surface that faces the crankshaft and an outer surface that faces the cover. The cooling member is configured such that rotation of the crankshaft causes lubricant in the crankcase to impinge on and drain down both the inner and outer surfaces of the cooling member.
The above patents are incorporated herein by reference in their entireties.

Marine engine crankcase cover with integral oil cooler


A dresser for dressing a polishing cloth adhered to a platen is provided with different dressing tools such as a lapping tool and a brush disposed around the lapping tool. In polishing, the platen is rotated and a wafer holding unit sucks and holds a wafer to press it against the polishing cloth while the wafer is rotated. In this manner, while polishing is performed, dressing is performed at the same time by pressing the dressing tools of the dresser against the polishing cloth. The brush and lapping tool may be rotated independently, or the dresser may be swung while it is rotated.

This application is based on Japanese patent application No. 8-90539 filed on Mar. 19, 1996, the entire contents of which are incorporated herein by reference.
a) Field of the Invention
The present invention relates to a polishing machine for polishing a subject such as a semiconductor wafer, and more particularly to a polishing machine having a dresser for dressing a polishing cloth.
b) Description of the Related Art
A polishing process is performed, for example, in order to planarize the interlayer insulating film formed on the surface of a semiconductor wafer. A known conventional polishing machine polishes a wafer by pressing it to a polishing cloth which is fixed to a rotary platen.
As the number of wafers polished with such a polishing machine increases, the polishing cloth is filled or choked up with polishing agent, scraped-off particles and the like. The polishing cloth may be deformed or abraded by rotation or load of wafers. With these reasons, the polishing performance may be degraded such as lowering a polishing speed, and a wafer may be damaged or contaminated.
A dressing function of reconditioning a polishing cloth choked up with foreign materials has been added to a polishing machine (refer to JP-A-4-364730 and JP-A-7-254578).
FIGS. 12 to 19 illustrate an example or a conventional polishing method for a polishing machine having a dressing function. A polishing machine 10 has a platen 12 to the surface of which a polishing cloth is adhered and a wafer receptacle 14 mounted near the platen 12. As shown in FIG. 19, a dresser 24 held by a dresser holder 22 is movably mounted on the polishing machine 10. This dresser 24 is not shown in FIGS. 12 to 18 for drawing simplicity. As a dressing tool of the dresser 24, one of a wire brush, a resin brush, a diamond disk conditioner and the like is used.
As shown in FIG. 20, a wafer holder 18 can hold a wafer 18 at the inside of a guide 26, by a vacuum chuck or the like, and is made movable so that the wafer holder 18 can press the wafer 18 against the polishing cloth on the platen 12 while being rotating by its rotary shaft 28.
At the process shown in FIG. 12, a subject wafer 16 is placed on the wafer receptacle 14, and at the process shown in FIG. 13 the wafer 16 is sucked by a vacuum chuck and held by the wafer holder 18.
Next, at the process shown in FIG. 14, the wafer holder 18 holding the wafer 16 is moved to the central area of the platen 12. At the process shown in FIG. 15, the wafer holder 18 is lowered to press the wafer 16 against the polishing cloth on the rotating platen 12. Polishing agent is supplied from a dispensing nozzle 20 onto the platen 12. The wafer 16 rotated and held by the wafer holder 18 and pressed against the polishing cloth is therefore polished.
After polishing, at the process shown in FIG. 16 the wafer holder 18 raises the wafer 16 from the platen 12. At the process shown in FIG. 17, the wafer holder 18 holding the wafer 16 is moved to the wafer receptacle 14 and unloads the wafer 16 down into the wafer receptacle 14 through release of suction by the vacuum chuck or through application of water pressure.
At the process shown in FIG. 18, the wafer holder 18 is moved to the initial position. At the process shown in FIG. 19, the dresser holder 22 moves the dresser 24 to the area over the platen 12. Thereafter, the dressing tool of the dresser 24 is pressed against the polishing cloth on the rotating platen 12 to dress the polishing cloth while the dresser 24 is rotated. In this case, cleaning liquid such as pure water may be supplied from an unrepresented pipe to clean the polishing cloth.
After dressing, the process returns to the process shown in FIG. 12 to execute a polishing process for the next wafer in the manner described above. Dressing may be performed after a plurality of wafers are polished, not by performing it each time a single wafer is polished.
The following properties (1) to (4) are generally required for dressing.
(1) brushing or lapping away choked foreign materials in polishing cloth (lapping) PA1 (2) removing foreign materials on polishing cloth (surface cleaning) PA1 (3) providing plastic deformation for elastic polishing cloth or other cloths (pressing) PA1 (4) raising naps of fibered polishing cloth or other cloths (uniforming)
Various kinds of dressing tools have been proposed. However, none of them can satisfy the requirements of the properties (1) to (4) at the same time, and only one or more properties can be provided.
For example, if a diamond disk conditioner having a large abrading ability is used as a dressing tool, scraped-off polishing cloth fibers and diamond grains are Left on the polishing cloth so that the wafer may be damaged or contaminated. If a dressing tool having no cleaning ability is used, contaminated polishing agent is supplied to the subject wafer during dressing.
Furthermore, since the conventional dressing process is performed independently from the polishing process, throughput of both the processes is lowered if the polishing performance is not stable.

Polishing machine with efficient polishing and dressing


According to one embodiment, a nonvolatile semiconductor memory device includes: a plurality of first semiconductor regions; a plurality of control gate electrodes; a charge storage layer; a first insulating film provided between the charge storage layer and first semiconductor regions; a second insulating film provided between the charge storage layer and control gate electrodes; and an element isolation region provided between the plurality of first semiconductor regions, and the element isolation region being in contact with the first insulating film and a first portion of the charge storage layer on the first insulating film side. Each of the plurality of control gate electrodes is in contact with a second portion other than the first portion of the charge storage layer. The charge storage layer includes a silicon-containing layer in contact with the first insulating film and a silicide-containing layer provided on the silicon-containing layer.

In a nonvolatile semiconductor memory device typified by a NAND flash memory, while miniaturization is progressing, the element isolation region is configured to have a prescribed depth to ensure the electrical insulation between elements.
However, with the progress of miniaturization, the width of the floating gate becomes narrower. Hence, there is a problem that depletion of the upper portion of the floating gate is likely to occur and the stability of writing and the stability of reading are not sufficient. Thus, a nonvolatile semiconductor memory device is desired that is good in the stability of writing and the stability of reading even when miniaturization progresses.

Nonvolatile semiconductor memory device and method for manufacturing same


A method of manufacturing a semiconductor nanowire semiconductor device is described. The method includes forming an amorphous channel material layer on a substrate, patterning the channel material layer to form semiconductor nanowires extending in a lateral direction on the substrate, and forming a cover layer covering an upper of the semiconductor nanowire. The cover layer and the nanowire are patterned to form a trench exposing a side section of an one end of the semiconductor nanowire and a catalyst material layer is formed in contact with a side surface of the semiconductor nanowire, and metal induced crystallization (MIC) by heat treatment is performed to crystallize the semiconductor nanowire in a length direction of the nanowire from the one end of the semiconductor nanowire in contact with the catalyst material.

High-performance semiconductor devices improve the quality of electronic products and come with benefits in terms of cost. Such a semiconductor device needs to have a semiconductor channel of high mobility and reliability, and in particular, as semiconductor channels have certain characteristics, it is necessary to reduce the characteristic spread.
AM-OLED (active-matrix organic light-emitting diode) displays are mainly applied to mobile devices of recent smartphones. As a pixel switching element of this AM-OLED display, a low temperature polycrystalline silicon thin film transistor (LTPS TFT) having high mobility and high reliability even under a high degree of integration is suitable.
Excimer Laser Annealing (ELA) is mainly applied to the manufacture of low-temperature polycrystalline silicon thin film transistors (LTPS TFT) for crystallization of silicon. The disadvantage of the LTPS TFT is that it is difficult to maintain a certain level of crystal grain uniformity when applied to a large-area display, and the yield is low.

Method for manufacturing a single-grained semiconductor nanowire


A connector assembly connects a hub connector to a wellhead housing by utilizing a collet. The collet has an upper internal projection that engages the hub connector and a lower internal projection that engages the flange on the wellhead housing. An actuator ring moves the collet from an unlocked to a locked position, the actuator ring moving axially. A drive nut, when rotated, will move the actuator ring downward. Load screws extending through the drive nut force the actuator ring further downward after the drive nut has reached its lower position. Release pins extending through the actuator ring, when rotated inward, will pry against a release surface to move the actuator ring upward relative to the drive nut.

1. Field of the invention
This invention relates in general to devices for connecting two tubular members together, and in particular to a mechanically locked wellhead connector.
2. Description of the Prior Art
In the oil industry, a well will commonly have a wellhead housing extending upward from the well. Pressure control equipment during drilling, or a christmas tree after drilling, mounts to the upper end of the wellhead housing. A wellhead connector will connect the pressure control equipment or tree to the wellhead housing.
Typically, the wellhead housing has an upper rim and a seal seat located at the upper rim. The wellhead connector body has a rim that abuts the rim of the wellhead housing. The seal seals between the hub connector body and the wellhead housing. Generally, the wellhead connector for use during drilling is large and hydraulically actuated. A piston when supplied with fluid will move a cam or actuator sleeve downward, forcing dogs into grooves formed on the wellhead housing. The wellhead connector for production need not be as large. Some utilize clamps without the need for hydraulic actuation. Others are hydraulically actuated, similar to the type used for drilling. While the prior art connectors serve sufficiently well, improvements in simplicity, size and ease of installation are desirable.


Static arrays of optical traps can be used to sort microscopic objects with exponential sensitivity to size. Such optical fractionation relies on competition between an externally applied force and the moving objects' differing affinities for optical gradient traps. In a reverse fractionation method, objects that are more strongly influenced by the traps tend to become kinetically locked in to the array and are systematically deflected back into an input flow. In a thermal ratcheting method, patterns are spaced to allow particle diffusion, thus providing the opportunity for forward or reverse movement through the patterns. Unlike other sorting techniques, optical fractionation can operate continuously and can be continuously optimized. The exponential sensitivity arises quite generally from the particle size dependence of the potential wells' apparent widths.

Optical tweezers use optical gradient forces to trap small, usually micrometer-scale, volumes of matter in both two and three dimensions. A holographic form of optical tweezer can use a computer-generated diffractive optical element to create large numbers of optical tweezers from a single laser beam. These tweezers can be arranged in any desired configuration dependent on the need at hand.
Although systems are known to move particles precisely and with a relatively high degree of confidence, conventional systems require a separate hologram to be projected for each discrete step of a particle's motion. Computing multiple holograms can be time consuming and requires substantial computational effort. Furthermore, computer-addressable projection systems required to implement such computer-generated optical tweezers or other dynamic optical tweezer systems, such as scanned optical tweezers, tend to be prohibitively expensive.

Optical fractionation methods and apparatus


A retractable safety needle apparatus is provided. The apparatus includes a needle holder with opposite proximal and distal ends. A needle assembly is mounted in the needle holder for movement from a first position where a distal cannula projects distally beyond the needle holder and a second position where the distal cannula is entirely within the needle holder. A spring is provided for propelling the needle assembly proximally and into the second position. The needle assembly includes a deflectable actuator for releasably holding the needle assembly in the first position and against the biasing forces of the spring. Portions of the needle holder adjacent the distal end are tapered to facilitate alignment of the needle assembly and to provide visual cues for proper orientation and gripping locations.

Many medical procedures require samples of bodily fluid, such as blood, to be collected and analyzed. The samples often are collected in an evacuated tube that has a cylindrical side wall, a closed bottom and an open top. The open top is closed by a needle pierceable and resealable material. Evacuated tubes of this general type are sold by Becton Dickinson under the trademark VACUTAINER®.
Evacuated tubes typically are employed with a needle assembly and a needle holder. The needle holder typically includes a rigid cylindrical side wall with proximal and distal ends. The proximal end of the side wall is widely open and is dimensioned for slidable receipt of the evacuated tube. A distal end wall extends across the distal end of the tubular side wall, and includes an aperture for engaging the needle assembly.
The typical needle assembly includes a plastic hub configured to mount in the aperture through the distal end wall of the needle holder. The needle assembly further includes a proximal needle cannula extending proximally from the hub and a distal needle cannula extending distally from the hub. Safety shields are mounted releasably to the needle hub for covering both the proximal and distal needle cannulas prior to use.
The needle holder and needle assembly are employed by first removing the safety shield from the proximal needle and mounting the needle hub in the aperture of the distal end wall of the needle holder. Thus, the proximal needle projects into the needle holder. The distal safety shield then may be removed and the distal needle cannula may be urged into a blood vessel or other source of bodily fluid. Typically the health care worker will align the needle holder so that the bevel at the distal end of the distal needle cannula faces up. Thus the health care worker will have to rotate the cylindrical needle holder by hand to achieve the preferred bevel orientation. Additionally, the health care worker will want as small an angle of entry of needle cannula into the patient as is permitted by the geometry of the needle holder.
An evacuated tube can be inserted into the open proximal end of the needle holder after the blood vessel or other source of bodily fluid has been accessed. Movement of the evacuated tube into the needle holder urges the proximal needle cannula into the evacuated tube and places the low pressure interior of the evacuated tube in communication with the source of bodily fluid. Hence, a flow of the bodily fluid is generated into the evacuated tube. The evacuated tube is separated from the needle holder after a sufficient volume of the fluid has been collected. Additional evacuated tubes can be urged sequentially into the needle holder to collect additional samples.
The needle holder and needle assembly are withdrawn from the patient after a sufficient number of fluid samples have been collected. The distal needle cannula then is shielded to prevent accidental sticks, and the shielded assembly is discarded in a sharps receptacle.
Many different shielding mechanisms are commercially available. Accordingly, there is a potential for improper shielding of a used needle cannula due to a lack of familiarity with the particular shield. A demand exists for a shieldable medical implement with an easy and efficient shielding mechanism and with visual and tactile cues to ensure that shielding is carried out efficiently and correctly.


An automatic calculation method for thickness calculation of a deposition layer in a Fin-type field-effect transistor (FinFET) is disclosed through mapping edge lines onto an Excel spreadsheet. The similar method is also applied to the thickness calculation of superlattice or multiple quantum well for a light emitting diode (LED). The edge lines are obtained and transformed from an electronic image taken by Transmission Electron Microscopy (TEM), Focus Ion Beam (FIB), Atomic Force Microscopy (AFM), or X-Ray Diffraction (XRD) of the device.

Technical Field
The present invention relates to a dimension calculation method for a semiconductor device, such as a FinFET or a LED. The boundaries or edge lines between neighboring layers are extracted from an electronic image taken by Transmission Electron Microscopy (TEM), Focus Ion Beam (FIB), Atomic Force Microscopy (AFM), or X-Ray Diffraction (XRD) over a semiconductor device.
Description of Related Art
In the process of semiconductor manufacturing, the performance of metrology equipment directly impacts yield. Fabs and equipment suppliers must ensure that their metrology results are within tolerances and maintain their ISO and QS quality certifications. This task becomes more challenging as the device features shrink and tolerances become tighter, to the extent of their physical limits in many cases. Especially, while the metrology tools in nanoscale regime provide 'precise, accurate, efficient, and effective' data; the error creeps in data collection, analysis, interpretation and presentation due to the manual or semi-auto data processing systems adopted in the present semiconductor industries. Accuracy of measurement not only depends on the metrology tools, but also directly depends on the data analysis and its interpretation. For example, nanoscale features imaged by XRD, SEM, AFM, FIB, TEM etc. and the critical dimensions are traditionally measured by manual over the images, which is not only consume a huge amount of time but also add an inaccuracy and uncertainty in the results. The results become meaningless while the inaccuracy and uncertainty become comparable to the tolerance. So the traditional manual or semi-auto data analysis or interpretation system thus cannot be reliable to estimate the nanoscale features from the data collected by the metrology tools. Therefore, an auto-metrology approach is eager in the semiconductor field to be developed for a more convincing and scientific to analyze and represent the data in a 'precise, accurate, efficient, and effective' way.
FIG. 1 shows a prior art
FIG. 1 shows a traditional metrology, e.g. thickness calculation, for a deposition layer of an electronic image, which comprises the following steps:
(1) Image providing;
(2) Dimension measuring; visual-manually operated;
(3) Data calculating; visual-manually operated; and
(4) Data outputting; visual-manually operated.

Dimension calculation method for a semiconductor device


An image processing method and analog front end circuit are described. An analog signal is converted to digital form to obtain a digital signal by increasing a conversion resolution value of an analog-to-digital converter module. The digital signal is subsequently amplified to obtain an amplified digital output signal.

High-end consumer and professional applications in a wide range of digital image acquisition systems, such as, for example, digital video camcorders, digital still cameras, personal computer video teleconferencing, digital copiers, and infrared image digitizers, require ever better image quality. Several attempts have been made to process signals received from certain sensor devices in such image systems and to provide high resolution output signals.
FIG. 1 is a block diagram illustrating an exemplary digital image acquisition system 100. The system 100 includes an image processing analog front end circuit 110 coupled to a Charge-Coupled Device (CCD) sensor 105 and further coupled to a digital image processing module 120, which includes a digital image processing unit 122, a compression and formatting unit 124, and a media interface 126.
FIG. 2 is a schematic diagram of a prior art image processing analog front end circuit 110 within the digital image acquisition system 100. As illustrated in FIG. 2, the circuit 110 includes an amplifier module 210, such as, for example a Programmable Gain Amplifier (PGA), coupled to an Analog-to-Digital Converter (ADC) module 220.
The PGA 210 is implemented with gain stages to receive an input analog signal 205 from the CCD sensor 105 and to amplify the analog signal 205 to the full scale range of the ADC module 220 in order to obtain an amplified analog signal 215. The ADC module 220 performs analog to digital conversion of the amplified analog signal 215. The ADC module 220 converts the amplified analog signal 215 into a digital output signal 225 through quantization and encoding operations. The ADC module 220 subdivides the range of the amplified analog signal 215 into a finite number of intervals, for example 2n−1 intervals, where "n" represents the number of bits available for a corresponding binary word of each interval, such as, for example, a value between 10 bits and 14 bits. Next, a binary word is assigned to each interval, i.e. to each range of signals, the binary word representing the digital representation of any signal that falls within that interval.
Because an entire interval of the input range is represented by a single digital value, some errors are necessarily present in the conversion operation and are called quantization errors. If a quantization error is different for different independent colors, this quantization error translates into image artifacts, such as, for example, color noise.
FIG. 3 is a diagram illustrating quantization values for separate independent colors. As shown in FIG. 3, considering the analog to digital output granularity as a function of the light intensity, different quantization errors on each independent color, for example the red and blue colors shown, create significant artifacts in the processed image.
In order to avoid such image artifacts, the PGA 210 is used before the ADC module 220 to equalize the relative amplitudes of the input signal for the different colors. This operation is sometimes called white balancing. The white balancing is performed in the digital image processing unit 120 of the image acquisition system 100, but partial color equalization is necessary to be done in the analog domain, prior to the ADC module 220, in order to avoid the image artifacts.
However, the addition of the PGA 210 to the analog front end circuit 110 takes a large portion of the total power dissipation and adds extra thermal noise to the signal path.
Thus, what is needed is an image processing method and analog front end circuit that will increase the resolution of the output signal without a corresponding increase in the power dissipation and noise within the circuit.

Image processing method and analog front end circuit