In an apparatus for driving a luminescent display panel, in a state in which scanning lines are sequentially scanned to drive and illuminate light-emitting elements, a voltage peak value arising in a scanning line in a non-scanning state is held by a capacitor through parasitic capacitance of the light-emitting element in a non-scanning state. On the basis of the voltage value held by the capacitor, a reverse bias voltage to be output from a reverse bias voltage generation circuit is controlled, and the voltage is supplied to the scanning lines.

1. Field of the Invention
The present invention relates to a technique for driving a capacitive light-emitting element; e.g., an organic electroluminescence (EL) element, to emit light. Particularly, the invention relates to an apparatus and method for driving a luminescent display panel which suppresses occurrence of crosstalk illumination of EL elements and can offer a suitable luminous brightness characteristic by means of appropriately controlling a reverse bias voltage to be applied to cathode scanning lines in a non-luminous state, as required, when a display panel having a plurality of organic EL elements arranged thereon is driven.
2. Description of the Related Art
An organic EL display has already been put into actual use in some quarters as a display which serves as an alternative to a liquid-crystal display and enables realization of low power consumption, high display quality, and a lower profile. An underlying backdrop to this is that the efficiency and life of an EL display have been improved to a practical level, by use of an organic compound—which can be expected to yield a superior light-emitting characteristic—for a light-emitting layer which is made of EL elements and is to be used for an EL display.
The organic EL element can be electrically represented as an equivalent circuit as shown in FIG. 4. The organic EL element can be replaced with a configuration consisting of a diode component E and a parasitic capacitance component Cp connected in parallel with the diode component E. The organic EL element is considered to be a capacitive light-emitting element. Illumination is considered to be effected in the following manner. When a luminous drive voltage is applied to the organic EL element, electric charges corresponding to the electrical capacitance of the element flow into and are stored in electrodes as a displacement current. Subsequently, when the electric charges have exceeded a given voltage inherent to the element (an emission threshold value=Vth), an electric current starts flowing from the electrode (i.e., the anode of the diode component E) into an organic layer constituting the light-emission layer. The light-emission layer illuminates at an intensity proportional to the electric current.
FIGS. 5A to 5C show a static light-emission characteristic of such an organic EL element. As shown in FIG. 5A, when a drive voltage (V) exceeds the emission threshold-value voltage (Vth), an electric current (I) abruptly flows into the organic EL element, whereupon the EL element illuminates. In other words, if the applied drive voltage is lower than the emission threshold-value voltage, a drive current does not flow into the EL element after recharging of the parasitic capacitance, and hence the EL element does not illuminate. As shown in FIG. 5B, within a light-generative domain in which the drive voltage (V) exceeds the emission threshold-value voltage, the EL element has a characteristic of illuminating at luminance (L) substantially proportional to the drive current (I). Consequently, as shown in FIG. 5C, within the light-generative domain in which the drive voltage (V) exceeds the threshold-value voltage the EL element has a luminance characteristic such that light-emission luminance of the EL element becomes greater as the value of the voltage (V) applied to the same increases.
The organic EL element has a characteristic of the physical properties thereof changing with long-term use and the resistance thereof becoming greater. As shown in FIG. 5A, with lapse of operating time a V—I characteristic of the organic EL element changes in the direction indicated by the arrowhead (i.e., assumes a characteristic designated by broken lines). Consequently, the luminance characteristic of the EL element also deteriorates.
The luminance characteristic of the organic EL element is also known to change roughly in the manner as indicated by broken lines in FIG. 5C according to an ambient temperature. Specifically, within the light-generative domain in which the drive voltage (V) exceeds the emission threshold-value voltage, the EL element has a characteristic of light-emission luminance (L) thereof becoming greater as the voltage (V) applied to the element becoming greater. However, the emission threshold-value voltage becomes lower as ambient temperature rises. Consequently, when heated to a higher temperature, the EL element becomes able to emit light at a lower applied voltage. Further, in relation to luminance, the EL element has temperature dependence of illuminating brightly at a high temperature and illuminating dimly at a low temperature even when a light-generative voltage has been applied to the EL element.
As a method of driving a display panel constituted by arranging a plurality of organic EL elements, a simple matrix drive system is applicable. FIG. 6 shows an example of a simple matrix display panel and a drive unit therefor. A method of driving organic EL elements of the simple matrix drive system includes two methods; that is, a method of scanning cathode lines and driving anode lines, and a method of scanning anode lines and driving cathode lines. The configuration shown in FIG. 6 is associated with the former method; that is, a method of scanning cathode lines and driving anode lines. More specifically, anode lines A1 through An serving as "n" drive lines are arranged in the vertical direction, and cathode lines B1 through Bm serving as "m" scanning lines are arranged in the horizontal direction. Organic EL elements (OEL) assigned diode symbols are disposed at respective intersections between the cathode and anode lines (a total of "n"דm").
The EL elements constituting pixels are arranged in a grid pattern. The EL elements constituting pixels are provided in corresponding intersections between the positive drive lines A1 through An laid vertically and the cathode scanning lines B1 through Bm laid horizontally. Each of the EL elements is connected at one end (e.g., an anode terminal of the diode component E in the previously-described equivalent circuit) to an anode drive line and at the other end (e.g., a cathode terminal of the diode component E in the equivalent circuit) to a cathode scanning line. The anode drive line is connected to and driven by an anode line drive circuit 2, and the cathode scanning line is connected to and driven by a cathode line scanning circuit 3.
The cathode line scanning circuit 3 is equipped with scanning switches SY1 through Sym corresponding to the respective cathode scanning lines B1 through Bm. The cathode line scanning circuit 3 operates so as to connect, to a corresponding cathode scanning line, either a reverse bias voltage (VM) output from a reverse bias voltage generation circuit 5 for preventing occurrence of crosstalk illumination, or a ground potential serving as a reference potential. Further, the anode line drive circuit 2 is equipped with constant current circuits I1 through In and drive switches SX1 through SXn, wherein the constant current circuits I1 through In act as constant current sources for supplying drive currents to the respective EL elements through corresponding anode drive lines.
The drive switches SX1 through SXn act so as to connect to corresponding anode lines either ground potential or the electric current output from the constant current circuits I1 through In. Hence, the drive switches SX1 through SXn are connected to the constant-current circuits I1 through In, whereby the electric currents output from the constant current circuit I1 through In are supplied to the respective EL elements arranged so as to correspond to the cathode scanning lines.
A drive source, such as a constant voltage circuit, may be used in place of the constant current circuit. The current/luminance characteristic of the EL element is stable, whereas a voltage/luminance characteristic of the same is unstable. In addition, a constant current circuit is generally used as a drive source, as shown in FIG. 6, for reasons of preventing deterioration of the element, which would otherwise be caused by excessively high current.
The anode line drive circuit 2 and the cathode line scanning circuit 3 are connected to an illumination control circuit 4 by way of control buses. On the basis of an image signal which is to be supplied to the illumination control circuit 4 and to be displayed, the scanning switches SY1 through Sym and the drive switches SX1 through SXn are actuated. On the basis of the image signal, the cathode scanning lines are set to a reference potential at predetermined cycles, and the constant current circuit is connected to a desired anode line. As a result, the respective light-emitting elements are selectively illuminated, whereupon an image is reproduced on the display panel 1 in accordance with the image signal.
A DC output (a drive voltage=VCOM) output from a booster circuit 6 constituted of a DC-DC converter is supplied to the respective constant current circuits I1 through In in the anode line drive circuit 2. The booster circuit 6 which is constituted of a DC-DC converter and will be described later produces a d.c. output through pulse width modulation (PWM) control. Alternatively, pulse frequency modulation (PWF) may be utilized.
The DC-DC converter is configured such that an n-p-n transistor Q1 serving as a switching element is activated at a predetermined duty cycle by means of a PWM waveform output from the switching regulator circuit 11. By means of activation of the transistor Q1, the electric power energy output from a DC voltage source 12 is accumulated in an inductor L1. In association with deactivation of the transistor Q1, the electric power energy accumulated in the inductor is stored in a capacitor Cl via a diode D1. Through repeated activation and deactivation of the transistor Q1, a boosted DC output can be obtained as a terminal voltage of the capacitor C1.
The DC output voltage is divided by a parallel circuit constituted of a resistor R3 and a thermistor TH1 for temperature compensation and at a junction between a resistor R1 and a resistor R2 connected in series with the parallel circuit. The thus-divided output voltage is supplied to an error amplifier 14 in the switching regulator circuit 11, the amplifier being constituted of an operational amplifier. The error amplifier 14 compares the output voltage with a reference voltage Vref. A comparison output (i.e., error output) is supplied to the PWM circuit 15, thereby controlling the duty cycle of a signal wave output from an oscillator 16. In this way, the DC-DC converter is subjected to feedback control such that the output voltage is maintained at a predetermined constant voltage.
By means of the configuration shown in FIG. 6, the thermistor TH1 is inserted into the feedback system so as to provide feedback to the error amplifier 14. The output voltage Vout produced by the DC-DC converter 6 is adjusted by means of the temperature characteristic of the thermistor TH1. Eventually, the reverse bias voltage VM—which is produced by means of dividing the output voltage Vout and will be described later—is varied in accordance with ambient temperature. Here, the output voltage Vout produced by the DC-DC converter 6 can be expressed as follows. In the following equation, "TH1//R3" denotes a parallel combined resistance value produced from the resistance of the thermistor TH1 and that of the resistor R3.Vout=Vrefx[(R1+R2+TH1//R3)/R1]
The reverse bias voltage generation circuit 5 utilized for preventing occurrence of the foregoing crosstalk illumination is constituted of a potential dividing circuit for dividing the output voltage Vout. The potential dividing circuit is constituted of resistors R4, R5 and an n-p-n transistor Q2 serving as an emitter follower. Therefore, when a base-emitter voltage in the transistor Q2 is taken as Vbe, the reverse bias voltage VM produced by the potential dividing circuit can be approximated as follows.VM=Vout×[R5/(R4+R5)]−Vbe
In the foregoing configuration, the illumination control circuit 4 controls the drive switches SX1 through SXn in the anode line drive circuit 2 in accordance with an image signal while scanning the cathode lines B1 through Bm in the cathode line scanning circuit 3 at a predetermined cycle, thus selectively connecting the constant-current circuits I1 through In to the respective anode drive lines A1 through An. At this time, the reverse bias voltage VM output from the reverse bias voltage generation circuit 5 is applied to the cathode lines in a non-scanning state. As a result, the EL elements connected to the interconnections between the anode line being driven and the cathode lines not selected for scanning operate so as to prevent occurrence of crosstalk illumination.
As mentioned previously, the organic EL element has the parasitic capacitance Cp. For instance, there is taken as an example a case where one anode drive line is connected to tens of EL elements, from the viewpoint of the anode drive line having a combined capacitance—which is greater than each parasitic capacitance by an order of magnitude—being connected to the anode drive line as load capacitance.
Consequently, the electric current output from the anode drive line at the leading end of a scanning period is spent in recharging the load capacitance. If the load capacitance is recharged until the emission threshold-value voltage of the EL element is sufficiently exceeded, a time lag will arise. This eventually presents a problem of a delay arising in start-up of the EL element. As mentioned previously, particularly in the case where the constant current sources II through In are used as a drive source, the constant current sources correspond to high-impedance output circuits in terms of principle of operation. Hence, a limitation is imposed on an electric current, thereby inducing a noticeable delay in the rise and illumination of the EL element.
The drive circuit of this type usually adopts a cathode resetting method. The cathode resetting method is described in, e.g., Japanese Patent Application Laid-Open No. 2320074/1997. When one scanning line has been switched to another scanning line, the method acts so as to speed up the rise and illumination of an EL element which is to be driven and illuminated by the current scanning line.
The drive switches SX1 through SXn provided in the anode line drive circuit 2 are connected to either the constant current sources I1 through In or the ground potential. When the switches SX1 through SXn are connected to the ground potential, the drive anode lines are set to the ground potential. Consequently, the cathode resetting method can be realized by utilization of the drive switches SX1 through SXn.
FIGS. 7A to 7D are illustrations for describing a cathode resetting operation. For instance, there is shown that a shift arises from a state in which an EL element E11 connected to the first anode drive line A1 is driven and activated to another state in which an EL element E12 connected to the first anode drive line A1 is driven and illuminated. In FIGS. 7A through 7D, an EL element to be driven and illuminated is depicted as a diode symbol, and the other EL elements are depicted as symbol of capacitors serving as parasitic capacitance.
FIG. 7A shows a state in which a cathode resetting operation is performed and in which the EL element E11 is illuminated as a result of a cathode line B1 having been scanned. The EL element E2 is to be illuminated through next scanning operation. However, before illumination of the EL element E12, the anode drive line A1 and all cathode scanning lines are reset to the ground potential as shown in FIG. 7B, thereby discharging all electric charges from the respective EL elements. To this end, the scanning switches SY1 through SYm are connected to ground, and the drive switch SX1 is connected to ground. In order to illuminate the EL element E12, a cathode scanning line B2 is scanned. In other words, the cathode scanning line B1 is grounded, and the remaining cathode scanning lines are given the reverse bias voltage VM. At this time, the drive switch SX1 is switched to the constant current source I1.
At the time of resetting operation, electric charges, which correspond to parasitic capacitance of the respective EL elements, are discharged. At this moment, as shown in FIG. 7C, the parasitic capacitance of the EL elements, except the EL element E12 which is to be illuminated next, is charged with the reverse bias voltage VM in a reverse direction as indicated by an arrow. This charging current flows into the EL element E12 to be illuminated next, via the anode drive line A1, thereby charging the parasitic capacitance of the EL element E12. At this time, as mentioned previously, the constant current source I1 connected to the drive line A1 in principle corresponds to a high-impedance output circuit. Hence, the constant current source I1 does not affect the flow of the charging current.
Provided that, for example, 64 EL elements are provided in the drive line A1 and that the reverse bias voltage is, e.g., 10(V), the potential V (A1) of the anode drive line A1 momentarily rises to a potential defined by Eq. 3 provided below through recharging operation, because line impedance of the panel is negligibly small. For instance, in the case of a display panel having outer dimensions of about 100 mm×25 mm (256×64 dots), a rise in the potential of the anode drive line is completed at about 1 μsec.V(A1)=(VM×63+0V×1)/64=9.84V
By means of the drive current which flows through the drive line A1 and originates from the constant current source I1, the EL element E12 is brought into an illuminating state, as shown in FIG. 7D. As has been described, the cathode resetting method acts so as to instantaneously increase the forward voltage of the next EL element be driven and illuminated, by utilization of parasitic capacitance of EL elements, which would originally hinder operation thereof, and a reverse bias voltage for preventing occurrence of crosstalk illumination.
When the cathode resetting method set forth is utilized, the forward voltage of an EL element to be driven and illuminated through the next scanning operation is started momentarily, and the EL element is driven and illuminated upon receipt of a drive current from the constant current source. Consequently, if the value of the reverse bias voltage VM is set higher, occurrence of crosstalk illumination can be effectively inhibited. Further, an initial charging voltage—which is a forward voltage to be supplied to an EL element to be illuminated through the next scanning operation—increases correspondingly. Therefore, at first glance the cathode resetting method is considered to be preferable. However, if the value of the reverse bias voltage VM is set excessively high, a so-called leakage phenomenon will arise, thereby deteriorating the display grade of the display panel. For this reason, in relation to a related-art drive circuit of this type, the reverse bias voltage VM is set to a fixed voltage close to the forward voltage Vf of the EL element.
As has been described by reference to FIG. 5A, the EL element of this type involves a problem of a forward voltage increasing with time. Further, as has been described by reference to FIG. 5C, the EL element of this type also involves a problem of a forward voltage varying in accordance with ambient temperature. For instance, in a case where a rise has arisen in a forward voltage after long-term use, a discrepancy gradually develops between a voltage VM with which an EL element is initially charged immediately before a scanning operation and the forward voltage Vf of the EL element, because the reverse bias voltage VM is a fixed voltage. Consequently, a delay arises in the time at which an EL element starts illuminating by means of an initial charging operation using the fixed reverse bias voltage VM, along with a problem of the quantity of illumination of the EL element gradually decreasing. In other words, a period during which a predetermined quantity of illumination of the EL element can be ensured is shortened, thereby turning into another problem of the life of the EL element becoming essentially short.
In addition to the changes with time and temperature dependence set forth, variations in film growth (deposition) treatment performed at the time of producing an EL element induce variations in the forward voltage of the EL element of this type. The EL element of this type involves a problem of a forward voltage changing according to the color of illumination, such as red (R) illumination, green (G) illumination, or blue (B) illumination. Eventually, variations arise in the light-emission luminance of the EL element.
Even in a case where a generation circuit constituted of a resistive divider and an emitter follower such as that shown in FIG. 6 is adopted as means for generating a reverse bias voltage VM, if the forward voltage Vf is higher than the reverse bias voltage VM, there arises a phenomenon of variations arising in an electric current which flows through an emitter-follower resistor via parasitic capacitance of respective EL elements in a non-scanning line in accordance with the number of elements illuminating in the display panel and with illumination luminance of the same. Therefore, the reverse bias voltage VM fluctuates, and variations arise in a potential difference between the reverse bias voltage VM and the forward voltage Vf of the element, eventually inducing variations in the illumination luminance of the EL element.
As shown in FIG. 6, even if the thermistor TH1 is used to consequently subject the reverse bias voltage VM to temperature compensation, the thermistor TH1 responds to temperature compensation slowly. Further, a temperature compensation curve does not necessarily match the characteristic of the EL element. For these reasons, difficulty is encountered in achieving a satisfactory compensation characteristic. Under ideal arrangement of the thermistor, the thermistor is brought into thermally intimate contact with a display panel. However, in reality, adoption of such a configuration is difficult, thereby posing difficulty in arranging and designing a thermistor.

Apparatus and method for driving luminescent display panel


An embodiment of the invention relates to a nonvolatile mass storage device such as a flash memory device formed with erase blocks partitioned into memory management blocks. An erase block is identified containing at least a minimum number of management blocks marked invalid, from which data is copied, merged, and stored in a new management block. The erase block is then erased. Erase blocks containing at least the minimum number of invalid management blocks may be erased until a minimum amount of management blocks is free. Alternatively, all erase blocks containing at least the minimum number of invalid management blocks may be erased. A management table listing the number of invalid management blocks in erase blocks may be included in the mass storage device. Preferably, the new management block for storage of the merged data is located in an erase block different from the identified erase block.

Mass storage memory devices such as flash cards, USB ("universal serial bus") sticks, or solid-state disks use flash semiconductor structures to store data in a nonvolatile memory device. A nonvolatile memory device refers to a memory device for which a power source can be switched "off" without losing the contents of the memory. Nonvolatile memory devices include flash memory devices that may semi-permanently retain an electric charge to represent one or more bits, or a "hard disk" (also referred to as a "hard drive") that may a semi-permanently retain a magnetic charge to store one or more bits. Semiconductor devices such as SRAMs (static random access memories) and DRAMs (dynamic random access memories) are referred to as volatile memory devices because they lose the contents of their memories if a bias voltage source is switched off.
Today's magnetic-based mass storage devices such as floppy disks or hard disks are organized in so-called sectors (a sector of being a portion of a "track" in the disk), each sector typically storing 512 bytes (in magnetic disks), and each sector identified with an individual logical block address (LBA). An LBA is a logical addressing scheme wherein a fixed one-to-one relationship is established between a sector of data and the physical location on the disk in which the respective sector of data is stored. The operating system of a computer collectively handles the LBAs of the mass storage device and builds a file system based thereon. The computer operating system reads and writes sequential amounts of LBAs with different block sizes from and to the mass storage device. In a hard disk, data can be freely written, read, or rewritten one or more sectors at a time.
Unlike magnetic memory devices, in flash memory devices there are restrictions regarding reading and writing of data. Flash memory devices are organized in pages, typically of size 4 kB (kilobytes) plus data protection headroom, and in erase blocks (also referred to herein as a "block"), for example, an erase block of size 64 pages. Accordingly, a 4 kB page of flash memory can store eight 512-byte sectors. A page of flash memory that is not programmed, i.e., a page that does not already contain data, can be written only as an entire page. Similarly, data can be read one page at a time. Flash memory has a further restriction in that it can be erased only a block at a time. Thus, to rewrite selected data in a portion of memory, an entire block must be read, erased, the new data merged with the previous data, and the merged data rewritten as a block, i.e., a copy and merge operation must be performed. Data can thus not be overwritten except as an entire block.
Writing and rewriting is generally referred to as programming. In a typical (NAND structured) flash memory, a page is written to all 1's to erase previously stored data, and can then be rewritten with the intended data. A block of data in a flash memory device is typically written to a different physical portion of the flash memory device to alleviate a wear-out problem associated with repetitively storing data in the same memory location. A translation (mapping) table stored in nonvolatile memory of the flash memory device is thus required in the communication link with a host computer to logically associate a sector of data with its physical location. A translation table is also generally moved each time it is rewritten. The restrictions of reading, writing, and rewriting in a flash memory device are also applicable to the translation table stored therein.
To execute a copy and merge operation, non-programmed blocks of memory must be available. Therefore, after several copy and merge operations, there are erase operations that are necessary to maintain availability of empty blocks for further erase operations.
In the ordinary operation of a flash memory device, i.e., a solid-state disk ("SSD"), coupled to a host computer, there are typically small amounts of new data that are required to be copied and merged with old data stored in an erase block. The merged data is stored in a new flash memory location. This results in a substantial amount of data that must be copied and merged for a small amount of new data to be stored due to do need to copy and merge all the unchanged data originally stored in the erase block.
A conventional way of handling free blocks of memory in a USB flash memory stick is the use of so-called log blocks. A log block provides a temporary area of memory (i.e., a previously erased erase block) to consecutively accumulate merged data, with appropriate updates to the mapping table. After valid data in an erase block are merged to a log block, the previous erase block location is identified as invalid and can be erased, making it available for another erase-block merging operation. This procedure is continued until all sectors of the log block are filled. When a log block is full, a new log block can be started. A garbage collection process refers to erasing erase blocks that contain invalid data to free the erase block up for reuse.
The disadvantage of this procedure is that a huge amount of data is typically copied before a single (invalid) block can be erased. For an USB memory stick where normally large amounts of consecutive sectors are written, this procedure provides reasonably satisfactory performance, since sectors are stored consecutively in the log block. But for an SSD with frequent random writes of small amounts of data, this procedure results in substantial inefficiency for erase operations.
Due to limitations of writing new data to flash memory devices using conventional procedures as described above wherein a large amount of data must be copied and merged for each write access before a single block can be erased, a more efficient solution for managing storage of new data in such devices is required. Thus, there is a need for a process and related method for an efficient erase operation that is necessary to be performed for storage of new data in the nonvolatile memory of a flash memory device that avoids the inefficiencies of conventional processes.

Process and method for erase strategy in solid state disks


According to the present invention, a laminar wrapping paper is provided comprising first and second paper layers or laminae. Each lamina has an inside surface coated with a barrier coating. The layers are laminated by heat lamination, wherein the barrier coatings are melted together, or by providing an adhesive between the coated inside surfaces. The lamination may be accomplished in a selective or discontinuous manner in order to form air pockets within the laminar structure to increase the insulation characteristics of the wrapping paper. A plasticizer is applied to the outside surface of the first lamina. Graphic designs or lettering may be printed on the outside surface to identify the wrapped product or for purposes of decoration. The present invention is also directed at a process and apparatus for manufacturing the laminar wrapping paper described herein. First and second webs of paper are unrolled and passed through coating apparatus to coat one side of each web with a barrier coating. An adhesive is applied to one of the coated sides of the webs to laminate the webs together, or alternatively heat lamination is performed using a hot roll. A plasticizer is then applied to the outer side of the first web.

Laminated paper wrapping has a variety of uses in the packaging industry. Many cost-efficient processes have been developed for producing stable wrappings consisting of cellulose- and foil-based layers bonded or adhered together. In the food wrapping industry, and particularly in the case of heated foods, several performance criteria should be met. The wrapping should have superior insulation properties in order to retain heat within the packaging for an acceptable period of time. Superior moisture retention is also desirable. In addition, an important criterion is the deadfold characteristics of the wrapping--that is, the ability of the wrapping once deformed around a food item to resist springing back or unwrapping.
These performance criteria have for the most part been achieved in foil and foil-to-paper wrappings. For many applications or situations, however, the use of foil is not desirable. One such instance is where microwave heating is contemplated, which is, of course, incompatible with metal foil. In addition, foil is more expensive than paper and as a waste product does not degrade satisfactorily. But while paper-to-paper wrappings are often favored, the deadfold, insulating and moisture retention properties of such products have thus far been less than satisfactory. As previously indicated, the "natural memory" inherent in paper tends to cause a paper-to-paper laminate to unfold after being wrapped around a food product.
With this background in mind, it is an object of the present invention to produce a paper-to-paper laminated wrapping which emulates the superior performance criteria of foil wrappings.

Process for manufacturing laminated wrapping paper


Engines and methods of controlling an engine may involve one or more cams associated with engine intake and/or exhaust valves. In some examples, shifting the rotational phase of one or more cams advances and/or delays timing of the opening and/or closing of valves. Timing of valve closing/opening and possible use of an air supply system may enable engine operation according to a Miller cycle.

An internal combustion engine may include one or more turbochargers for compressing a fluid, which is supplied to one or more combustion chambers within corresponding combustion cylinders. Each turbocharger typically includes a turbine driven by exhaust gases of the engine and a compressor driven by the turbine. The compressor receives the fluid to be compressed and supplies the compressed fluid to the combustion chambers. The fluid compressed by the compressor may be in the form of combustion air or an air/fuel mixture.
An internal combustion engine may also include a supercharger arranged in series with a turbocharger compressor of an engine. U.S. Pat. No. 6,273,076 (Beck et al., issued Aug. 14, 2001) discloses a supercharger having a turbine that drives a compressor to increase the pressure of air flowing to a turbocharger compressor of an engine.
While a turbocharger may utilize some energy from the engine exhaust, the series supercharger/turbocharger arrangement does not utilize energy from the turbocharger exhaust. Furthermore, the supercharger requires an additional energy source.
The operation of an internal combustion engine, such as, for example, a diesel, gasoline, or natural gas engine, may cause the generation of undesirable emissions. These emissions, which may include particulates and oxides of nitrogen (NOx), are generated when fuel is combusted in a combustion chamber of the engine. An exhaust stroke of an engine piston forces exhaust gas, which may include these emissions, from the engine. If no emission reduction measures are in place, these undesirable emissions will eventually be exhausted to the environment.
Research is currently being directed towards decreasing the amount of undesirable emissions that are exhausted to the environment during the operation of an engine. Unfortunately, the implementation of emission reduction approaches typically results in a decrease in the overall efficiency of the engine.
Additional efforts are being focused on improving engine efficiency to compensate for the efficiency loss due to the emission reduction systems. One such approach to improving the engine efficiency involves adjusting the actuation timing of the engine valves. For example, the actuation timing of the intake and exhaust valves may be modified to implement a variation on the typical diesel or Otto cycle known as the Miller cycle. In a "late intake" type Miller cycle, the intake valves of the engine are held open during a portion of the compression stroke of the piston. Selective implementation of a variation on the conventional actuation timing, such as the Miller cycle, may lead to an improvement in the overall efficiency of the engine.
The engine valves in an internal combustion engine are typically driven by a cam arrangement that is operatively connected to the crankshaft of the engine. The rotation of the crankshaft results in a corresponding rotation of a cam that drives one or more cam followers. The movement of the cam followers results in the opening and closing of the engine valves. The shape of the cam typically governs the timing and duration of the valve opening/closing. As described in U.S. Pat. No. 6,237,551 to Macor et al., issued on May 29, 2001, a "late intake" Miller cycle may be implemented in such a cam arrangement by modifying the shape of the cam to overlap the actuation of the intake valve with the start of the compression stroke of the piston.
As noted above, the timing of a valve system driven by a cam arrangement is determined by the shape of the driving cam. Because the shape of the cam is fixed, this type of arrangement is sometimes inflexible and often only capable of permitting a varied timing through the use of complex mechanisms.
The present disclosure is directed to possibly addressing one or more drawbacks associated with prior approaches.

Combustion engine including cam phase-shifting


The present invention provides a novel protein containing an armadillo repeat, a gene encoding this protein, and production and use thereof. The present inventors identified a gene named ALEX1 encoding a human-derived novel armadillo repeat-containing protein. It was clarified that ALEX1 interacts with several proteins including insulin-degrading enzyme, presenilin-1, and JNK interacting protein 1. This gene shows significantly decreased expression in cancer cells. The protein ALEX1 and the gene encoding this protein are usable as tools in testing for diseases such as cancer and Alzheimer's disease and developing pharmaceutical agents.

Members of the armadillo (Arm) family of proteins are homologous to the product of the armadillo gene of Drosophila and have been implicated in a variety of important cell functions. The common characteristic of all armadillo-related proteins is a series of imperfect 42-amino acid repeats (Arm motifs) (Peifer, M. et al. (1994) Cell 76, 789-791). The motif was first described in 1989 in the armadillo locus in Drosophila (Riggleman, B. et al. (1989) Genes Dev. 3, 96-113). Since then, a number of genes encoding proteins containing homologous motifs have been cloned and sequenced. These include: human α-, β-, γ-, δ-catenins; the tumor suppressor adenoma polyposis coli (APC); p120, the substrate of src protein kinases; importin involved in the nuclear import of proteins; and smgGDS involved in the guanine nucleotide conversion of low molecular weight G-proteins such as ras (Hatzfeld, M. (1999) Int. Rev. Cytol. 186, 179-224). Arm motifs are found throughout evolution and are conserved even between distant species like yeast and human. Arm repeats in proteins usually occur in tandem and, so far, no proteins with less than six repeats have been described. It is known that armadillo-related proteins interact with numerous different proteins through their Arm domains (Ozawa, M. et al. (1995) J. Biochem. (Tokyo) 118, 1077-1082; Rubinfeld, B. et al. (1995) J. Biol. Chem. 270, 5549-5555; Troyanovsky, R. B. et al. (1996) J. Cell Sci. 109, 3069-3078; Murayama, M. et al. (1998) FEBS Lett. 433, 73-77).
Recent studies have implicated Arm proteins in Alzheimer's disease. Human Arm-proteins β-, γ-, δ-catenins and p0071 have been found to interact with presenilin-1 (PS1) protein (Zhou, J. et al. (1997) NeuroReport 8, 2085-2090; Zhang, Z. et al. (1998) Nature 395, 698-702; Stahl, B. et al. (1999) J. Biol. Chem. 274, 9141-9148). Mutations of the PS1 and presenilin-2 (PS2) genes are responsible for the majority of cases of early-onset familiar Alzheimer's disease (Price, D. L., and Sisodia, S. S. (1998) Annu. Rev. Neurosci. 21, 479-505). PS1 and PS2 mutations increase the levels of the β-amyloid peptide 1-42 deposited at the core of amyloid plaques suggesting that presenilins are involved in the processing of amyloid precursor proteins (APP). The significance of interaction of catenins with presenilins is unclear, although it appears that wild-type PS1 can stabilize β-catenin, whereas PS1 mutants show loss of the stabilizing function.
As mentioned above, Arm proteins serve different functions in cells. The Drosophila armadillo gene was first identified as a component of the wingless signaling cascade (Wieschaus, E., and Riggleman, R. (1987) Cell 49, 177-184). Similarly, the vertebrate equivalent of armadillo, β-catenin, is known as a critical component of the Wnt/Wingless growth factor signaling pathway that governs cell fate choice in early embryogenesis. The mechanism of how β-catenin transduces the Wnt/wingless signal has been elucidated by the discovery that β-catenin forms a complex with members of the TCF/LEF-1 family of transcription factors that enters the nucleus (Behrens, J. et al. (1996) Nature 382, 638-642; Molenaar, M. et al. (1996) Cell 86, 391-399). TCFs are poor transcriptional activators, but complexes of TCF/LEF-1 and β-catenin act as strong transcriptional activators.
In addition to its role in signaling functions, β-catenin has an essential role in the morphogenesis of solid tissues and the subsequent maintenance of tissue integrity. β-catenin binds to the highly conserved cytoplasmic domain of cadherins and to α-catenin, which binds to actin. The cadherin-catenin complex is a target of regulatory signals that govern cellular adhesiveness and mobility (Kinch, M. S. et al. (1995) J. Cell. Biol. 130, 461-471).
In mammalian cells, β-catenin interacts with the tumor suppressor gene product APC (Su, L. K. et al. (1993) Science 262, 1734-1737). Mutations in APC gene are associated with familial and sporadic colorectal cancer (Kinzler, K. W., and Vogelstein, B. (1996) Cell 87, 159-170). APC is thought to function to decrease β-catenin stability since APC mutant proteins lacking β-catenin binding site display elevated levels of cytosolic β-catenin and constitutive transcriptional activation of the β-catenin/TCF complex.
Thus, Arm proteins are involved in the maintenance of tissue structures as well as intracellular signaling functions. They play a central role in tumorigenesis and are implicated in Alzheimer's disease. Therefore, it is thought that newly discovered members of the Arm family of proteins might be involved in these pathologies and, thus, represent useful targets for the development of therapeutics.
Recent studies from several laboratories demonstrated that insulin-degrading enzyme (IDE) is the main amyloid β peptide-degrading enzyme at neutral pH in rat and human nervous tissues (Kurochkin, I. V., and Goto, S. (1994) FEBS Lett. 345, 33-37; McDermott, J. R., and Gibson, A. M. (1997) Neurochem. Res. 22, 49-56; Qiu, W. Q. et al. (1998) J. Biol. Chem. 273, 32730-32738). Since most of IDE is localized to the cytoplasm, it is unclear how the protease could gain access to amyloid β peptide generated in a secretory organelle from an amyloid precursor protein (APP).


A multiple-chip probe assembly suitable for wafer testing over a wide temperature range includes a plurality of individual buckling beam probe elements. A support structure supports the plurality of buckling beam probe elements in an arrangement in accordance with an electrical contact footprint for use in electrically contacting multiple chips of a wafer under test and enables buckling movement in a contacting direction of the plurality of buckling beams. The support structure includes a principal support material having a thermal coefficient of expansion (TCE) matched with the wafer under test and a second material other than the principal support material, wherein a contact positioning of the plurality of buckling beam probe elements upon the wafer under test during a testing operation is maintained. The second material prevents an individual probe element from electrically contacting the principal support material.

1. Field of the Invention
This invention relates generally to electronic devices for testing and burning-in integrated circuits and, more particularly, to a multiple-chip probe assembly for use in a wafer test and burn-in system.
2. Discussion of the Related Art
Electronic integrated circuitry is burned-in under extreme conditions of temperature and voltage after manufacture in order to exaggerate the failure rate of defective circuitry while ensuring greater reliability of the circuitry which survives the stressful conditions. Because the rate of electronic component failure is significantly higher during the early life of a component, testing under stressful conditions is an effective method of identifying integrated circuit chips which would likely experience early failure in the field.
Systems for burning-in individual integrated circuit chips are available but expensive and difficult to make. Burn-in would be best accomplished while the individual circuits reside on their respective wafers before dicing into individual chips. Such a method of wafer-level burn-in has long been sought in the industry. As described in commonly assigned U.S. Pat. No. 5,600,257, entitled SEMI-CONDUCTOR WAFER TEST AND BURN-IN, problems with wafer level burn-in include alignment of test probes and thermal matching. As for probe alignment, each of the integrated circuits on the wafer has contact points on the surface of the wafer which must be contacted by a particular probe element of a multi-probe element test head assembly. The diminutive size of the test contact points requires that the probe elements of the test head assembly be of an appropriately small size, and further that the test head probe elements be precisely aligned with the test contact points on the integrated circuits undergoing the test.
The precise alignment between the probe elements of the test head assembly and the test contact points on the integrated circuits is difficult to maintain over the temperature range utilized during burn-in, for example, at temperatures between about 100.degree. C. to 160.degree. C. Probe elements, for example, may include cobra probes, such as described in commonly assigned U.S. Pat. No. 4,027,925 to Byrnes et al., entitled CONTACT FOR AN ELECTRICAL CONTACTOR ASSEMBLY. Heating of the wafer, which is typically comprised of silicon, results in expansion (in all three axes X,Y,Z) which cause problems due to the diminutive size of the test contact points on the integrated circuits of the wafer. The probe elements can also be affected. As a result, the probe elements of the test head assembly may become misaligned with respect to these test contact points to such an extent that the probe elements no longer contact the test contact points. Maintaining contact is of critical importance in most aspects of testing and burn-in.
As described in the '257 patent, the problem has been solved by providing the test head assembly with a material possessing the same or similar thermal expansion coefficient as that of silicon. At the same time, the test head assembly must provide means to effectively and accurately position the probe elements so that proper initial contact may be made and maintained with the test contact points on the integrated circuits being tested.
In addition to the above, contacting probe systems for wafer test currently permit contact of 1 to 16 chip sites of a wafer under test at a single time. As a result, multiple probings are required to test all of the chip sites of the wafer.
It is thus desirable to provide an improved probe assembly for testing the chip sites of an entire wafer at a single time during testing, and to provide a method of constructing the probe assembly.

Large area multiple-chip probe assembly and method of making the same

International Business Machines Corporation


The present invention is related to a compound conjugating a drug with a glycosaminoglycan, such as hyaluronic acid (HA), where the drug is useful for the treatment of diseases such as inflammation, auto-immune disease, allergy, infection and preferably cancer. The conjugated compound of the present invention can increase the concentration of drug at the specific site of disease by an interaction of the glycosaminoglycan used as target drug delivery carrier and the CD44 cell surface receptor, then enhancing the therapeutic efficacy and reducing the systemic side effect of the site-delivered drug.

1. Field of the Invention
The present invention relates to a compound consisting of a glycosaminoglycan conjugated with a drug and to a preparation method thereof as well.
2. Description of the Prior Arts
The extracellular matrix (ECM) is a dynamic assemblage of interacting molecules that regulate cell functions and interactions in response to stimulation. One class of extracellular matrix macromolecules, the glycosaminoglycans, are molecules known to be involved in a wide array of both normal and abnormal biological processes, including cell migration, differentiation, proliferation, immune response and cytoskeletal organization.
Glycosaminoglycans (GAGs) are unbranched chains composed of repeating disaccharide units. These disaccharide units always contain an amino sugar (N-acetylglucosamine or N-acetylgalactosamine), which in most cases is sulfated, with the second sugar usually being an uronic acid (glucuronic or iduronic). GAGs are highly negatively charged because of the presence of carboxyl or sulfate groups on most of their sugar residues. As such they are strongly hydrophilic. GAGs tend to adopt highly extended conformations and form matrices that are space filling and resistant to compressive forces. Four main groups of GAGs have been distinguished by their sugar residues, the type of linkage between these residues, and the number and location of sulfate groups. They include: (1) hyaluronan, (2) chondroitin sulphate and dermatan sulfate, (3) heparan sulfate and heparin, and (4) keratan sulfate.
Hyaluronan (also called hyaluronic acid or hyaluronate or HA) is the simplest of GAGs. It consists of a regular repeating sequence of non-sulfated disaccharide units, specifically N-acetylglucosamine and glucuronic acid. Its molecular weight can range from 400 daltons (the disaccharide) to over millions of daltons. It is found in variable amounts in all tissues, such as the skin, cartilage, and eye, and in most, if not all, fluids in adult animals. It is especially abundant in early embryos. In articular cartilage, HA can form a large aggregate which is important for the function of cartilage. Furthermore, cell motility and immune cell adhesion is mediated by the cell surface receptor RHAMM (Receptor for Hyaluronan-Mediated Motility) and CD44.
HA is synthesized directly at the inner membrane of the cell surface with the growing polymer extruded through the membrane to the outside of the cell as it is being synthesized. Synthesis is mediated by a single protein enzyme, hyaluronan synthetase (HAS). By contrast, other GAGs are synthesized inside the cell in the Golgi apparatus, possibly in association with some core protein, and then released by exocytosis. HA degradation in vertebrate tissues in vivo is mediated by hyaluronidase, and exoglycosidases that remove sugars sequentially. Mammalian-type hyaluronidases have both hydrolytic and transglycosidase activities and can degrade HA and chondroitin. In connective tissue, the water of hydration associated with HA creates spaces between tissues, thus creating an environment conducive to cell movement and proliferation. HA plays a key role in biological phenomena associated with cell motility including rapid development, regeneration, repair, embryogenesis, embryological development, wound healing, angiogenesis, and tumorigenesis.
CD44 (also known as Pgp-1, Hermes-3, HCAM, ECMR III) is a widely expressed glycoprotein with a molecular weight of 85 to 90 kDa. CD44 is a major cell surface receptor for the glycosaminoglycan, hyaluronic acid (HA). CD44 binds HA specifically, although certain chondroitin-sulfate containing proteoglycans may also be recognized. CD44 plays a role in various cellular and physiological functions, including adhesion to and migration on HA, HA degradation and tumor metastasis. CD44 has also been shown to play a role in extracellular matrix binding, cell migration, lymphocyte activation, lymphocyte homing, and proliferation of bronchial smooth muscle cell (Gunthert et al., 1991, A new variant of glycoprotein CD44 confers metastatic potential to rat carcinoma cells, 5; 65(1):13-24). The CD44 receptor shows a complex pattern of alternative splicing in its variable region of the extracellular domain. CD44 appears to be a particularly important leukocyte receptor for HA and may therefore have a role in the pathogenesis of asthma. In addition, levels of HA, which were increased during experimental asthma in control mice were markedly attenuated in the antibody-treated mice, supporting a role for CD44 in HA metabolism (specifically in the breakdown of high molecular weight HA to pro-inflammatory low molecular weight forms). This may be particularly important because HA-derived oligosaccharides can bind and activate Toll-like receptor. Clearly, the most impressive aspect of the results is the profound magnitude of the beneficial effects of anti-CD44 treatment.
HA-CD44 interactions may play an important role in development, inflammation, T cell recruitment and activation, lung inflammation, and tumor growth and metastasis. Altered expression of alternatively spliced CD44 transcripts has been found in many cancers, including cancer of the stomach (F Reihani-Sabet et al., 2003, Effects of Inflammation and H. pylori Infection on Expression of CD44 Variant Exons in Gastric Tissue, Journal of Sciences, 14:11-16).
Malignant tumor cells could selectively ingest proportionally more of bioconjugates than normal connective tissue or mesenchymal cells due to their overexpression of the CD44 receptor. Several studies have correlated increased HA synthesis and uptake with cancer progression and metastatic potential. Certain tumors, including many that are found in the lung, overexpress the CD44 cell-surface marker. Breast cancer cells are known to have greater uptake of HA than normal tissues, requiring HA for high P-glycoprotein expression, the primary contributor to multi-drug resistance. Furthermore, invasive breast cancer cells overexpress CD44, the primary receptor for HA, and are dependent on high concentrations of CD44-internalized HA for proliferation. Thus, chemotherapeutic drug nanoconjugates with HA may be efficacious against lymphatic metastases. (Eliaz, R. E. et al., 2004, Liposome-encapsulated doxorubicin targeted to CD44: a strategy to kill CD44-overexpressing tumor cells, Cancer Res., 61(6):2592-601).
Non-steroidal anti-inflammatory drugs (NSAIDs) and selective inhibitors of cyclooxygenase (COX)-2, are therapeutic groups generally used for the treatment of pain, inflammation and fever. Recently, growing experimental implies that some NSAIDs and the selective COX-2 inhibitors may also have anti-cancer activity by involving in multiple biologic events throughout the tumorigenic process. For example, epidemiological studies have shown that regular use of Aspirin reduces the risk of developing cancer, in particular of the colon (Sandler R S., et al., 2003, A randomized trial of aspirin to prevent colorectal adenomas in patients with previous colorectal cancer, New England J. Med., 348:883-890). Otherwise, it is also found that the COX-2 antagonist, such as Celecoxib, Rofecoxib, Nimesulide, meloxicam and Etodolac, can also have anti-cancer activity (Yamazaki R., et al., 2002, Selective cyclooxygenase-2 inhibitors show a differential ability to inhibit proliferation and induce apoptosis of colon adenocarcinoma cells, FEBS Lett., 531(2):278-84). Further, COX-2 is chronically overexpressed in many premalignant, malignant, and metastatic human cancers, and levels of overexpression have been shown to significantly correlate to invasiveness, prognosis, and survival in some cancers (Dannenberg A J., et al., 2003, Targeting cyclooxygenase-2 in human neoplasia: rationale and promise, Cancer Cell, 4(6):431-6). Maximum efficacy is typically dose-limited by COX-1-related toxicities; however, COX-2 inhibitors have been shown to have tumor suppression effect in several animal models of colon, skin, lung, bladder, and breast cancers (Alane T. Koki, et al., 2002, Celecoxib: A Specific COX-2 Inhibitor With Anticancer Properties, Cancer Control, 9(2 Suppl):28-35).
WO94/09811 describes the use of CD44 in treating inflammation or detecting cancer metastasis. The authors show that CD44 is upregulated in inflammatory conditions and CD44 peptides are capable of inhibiting T-cell activation. No data or claims are presented on inhibition of metastasis by CD44 and no claims are made towards use of CD44 for inhibiting tumor growth or angiogenesis. WO 99/45942 discloses the use of HA-binding proteins and peptides, including CD44, to inhibit cancer and angiogenesis-dependent diseases. This patent application uses metastatin, a 38 kDa fragment of the cartilage link protein, as well as a HA-binding peptide derived from this fragment to inhibit pulmonary metastasis of B16 mouse melanoma and Lewis lung carcinoma. In the case of the HA-binding peptide, growth of B16 melanoma on chicken CAM and endothelial cell migration on HA have been inhibited. In both patent applications the use of HA-binding peptides is directly related to their ability to bind hyaluronic acid.
U.S. Pat. No. 8,192,744 shows that soluble recombinant CD44 hyaluronic acid binding domain (CD44HABD) inhibits angiogenesis in vivo in chick and mouse and thereby inhibits human tumor growth of various origins. The invention discloses soluble non glycosylated CD44 recombinant proteins as a novel class of angiogenesis inhibitors based on targeting of vascular cell surface receptor.
Thus, the prior arts, hereinabove cited, disclose the potential use of CD44 and suggest that any effects can be dependent on HA-CD44-interaction. Consequently, all utility ascribed so far to CD44-HA conjugate is directly dependent on their ability to bind hyaluronic acid.
However, some drugs are still not successfully conjugated onto HA and further experiments should be carried out to confirm the potential usefulness of HA as site-delivery carrier of active compound. In particular, the prior art has not shown that the interactions between the surface cell receptor CD44 and a conjugate of HA with an active compound can be profitably exploited for a target delivery of such active compound in diseases characterized by an overexpression of CD44 obtaining an effective therapeutic improvement of the same.
For pathologies, such as for example cancer, in fact, it is still a need felt to have available therapeutic tools balancing an effective cytotoxic effect against the tumoral cells and the cytotoxic effects on the normal cells with a better safety profile.

Compound of glycosaminoglycan and its fabrication method as well as application


Disclosed are methods for the application of a cyanoacrylate/anti-microbial composition over mammalian skin surfaces to peri-wound and peri-mucosal areas. The composition can also be applied over medicament that has been applied onto the skin surface.

Field of the Invention
This invention is directed to the use of cyanoacrylate/PVP-iodine compositions for the treatment of the peri-wound or peri-mucosal skin. Specifically, the methods of this invention involve the application of a cyanoacrylate/PVP-iodine composition over mammalian skin surfaces peripheral to and surrounding a wound or a mucosal area such as a stoma. The composition can be applied to form a protective barrier layer on skin that is exposed to urine or fecal waste. The composition can also be applied over medicament that has been applied onto the skin surface. The cyanoacrylate composition to be used can be stored in dispensers for single or repeated/intermittent use and can be applied to the skin by spraying, painting etc. of the composition.

Application of cyanoacrylate/anti-microbial compositions to the peri-wound or peri-mucosal area


The present housing for coin selectors is provided with an electronic circuit wherein are included elements for measuring the variation of the field produced by the passage of coins through a magnetic field generated by a group of coils, said housing being provided, on one of its faces (9) corresponding to the paths of coins, with various ribs (10) parallel to each other and parallel with the rolling ramp for the coins, preferably three ribs, with self-cleaning effect which avoids the deposition of dirt entrained by the coins.

The present invention relates to a housing for coin selectors, specifically for selectors with electromagnetic coils which generate a magnetic field which is modified by the coins in its path, as a function of the intrinsic characteristics of each coin; or with selectors having sensors of an optical type. This housing has been perfected in order to avoid the classical problems arising from dirt deposited by the passing coins.
One of the most advanced and effective solutions in the area of coin selectors consists of using an electronic circuit in the pathway of coins which is capable of measuring the fluctuations in the magnetic field caused by the coins. This field is generated by a series of coils, such that with the collaboration of a series of standard measurements, the device is capable of selecting different types of coins, not only by their dimensions but also by the nature of the material from which the coins are made.
To this end, the housing of the selector is provided with a rolling ramp suitable for the passage of coins and designed to carry out the pertinent measurements. More specifically, the housing is provided with two sections joined to one another in a tilted manner, which reach their limiting positions through the use of a spring. One of these sections incorporates the electronic circuit cited above, and the other incorporates the electromagnetic coils or optical sensors, as the case may be, with a "laminar" space defined between the two, which is closed on its lower side by a thin, oblique wall belonging to one of the two sections and which determines the above-cited coin rolling ramp, and which is obviously parallel to the imaginary alignment line of the coils.
Moreover, the coins, because of their constant circulation and change of ownership, are often dirty. This dirt gradually accumulates on the areas of the housing that enter into contact with the coins, specifically on those areas of the housing where the vital elements of the housing are located, that is, on the measurement zone.
This accumulation of dirt on the coin pathways brings with it the fundamental problem of having to periodically and frequently clean the selector; otherwise, the selector will reject the coins.


Pyrogenically prepared surface-modified silicon dioxide-titanium dioxide mixed oxides are prepared by spraying pyrogenically prepared silicon dioxide-titanium dioxide mixed oxides with a surface-modifying agent. The surface-modified pyrogenically prepared silicon dioxide-titanium dioxide mixed oxides can be used in sun protection formulation.

Cosmetic preparations, such as creams or lotions, comprising UV filters are used to protect the skin from too intensive UV radiation. As UV filters these preparations generally comprise one or more organic compounds which absorb in the wavelength range from 290 to 400 nm, which is divided into the ranges: UVB radiation (290 to 320 nm); UVA radiation (320 to 400 nm).
UVB radiation, which is higher-energy, causes the typical symptoms of sunburn and also causes suppression of the immune defence, while UVA radiation, which penetrates more deeply into the layers of the skin, causes premature ageing of the skin. Because the cooperation of the two types of radiation is said to promote the development of skin diseases caused by light, such as skin cancer, there has been a search for possible ways of further improving significantly UV protection.
Metal oxides, such as titanium dioxide or zinc oxide, are widely used in sun protection agents. Their action is based substantially on the reflection, scattering and absorption of the damaging UV radiation and is dependent substantially on the primary particle size of the metal oxides. Microfine titanium dioxide is used in many cosmetic formulations because it is chemically inert and toxicologically harmless and results neither in skin irritations nor sensitisation. Microfine titanium dioxide can be prepared by wet chemical precipitation processes or thermal (pyrogenic) gas-phase processes.
Pyrogenically prepared silicon dioxide-titanium dioxide mixed oxide is known from DE 4235996. A disadvantage of the known pyrogenically prepared silicon dioxide-titanium dioxide mixed oxide is its photocatalytic activity, which initiates reactions that can lead to a change in constituents of a sun protection agent. Numerous methods have therefore been developed for lowering the photocatalytic activity of these metal oxides without reducing their UV-screening properties, for example by surrounding them with a shell of silicon dioxide and/or aluminium oxide.
The photoactivity of titanium dioxides can also be reduced by rendering them hydrophobic with organosilanes. A microfine, pyrogenic titanium dioxide that has been established on the market for many years is titanium dioxide T 805 or AEROXIDE TiO2 T 805 (Degussa AG). This product can be prepared by the flame hydrolysis of titanium tetrachloride according to the AEROSIL process and subsequently rendering the product hydrophobic with an organosilane. Pyrogenic titanium-iron mixed oxides that have been rendered hydrophobic are described, for example, in EP 0722992.
However, hydrophobic, pyrogenic titanium dioxides cannot be dispersed in the water phase of a sun protection emulsion but only in the oil phase. However, because the water phase generally accounts for more than 60%, the larger part of a sun protection formulation cannot be used as "carrier" for titanium dioxide. Consequently, the titanium dioxide content of a sun protection emulsion has an upper limit and is generally only from 3 to 5 wt. %, based on the total formulation. This means, that without the addition of further organic UV filters and/or zinc oxides, sun protection agents having a light protection factor >10 are difficult to produce.
Surface-treated hydrophilic, pyrogenic titanium dioxides can be prepared by coating them with silicon dioxide, as described, for example, in DE 10260718 and further publications mentioned therein. However, such materials exhibit a pronounced photoactivity and therefore have only limited suitability for use as UV filters.
Further disadvantages of known hydrophobic and hydrophilic, pyrogenic titanium dioxides are:    insufficient transparency of the sun protection formulations prepared therewith on application to the skin    complicated dispersion is necessary    a pronounced thickening effect on dispersion in, for example, cosmetic oils or water makes it difficult to prepare dispersions or sun protection agents having a high TiO2 content    the sun protection formulations that are prepared feel dull on the skin.
Accordingly, one object in this area is to find a pyrogenically prepared silicon dioxide-titanium dioxide mixed oxide that does not exhibit these disadvantages. A further object to prepare sun protection agents that have improved transparency and sensory properties and that have a high sun protection factor.

Surface-modified silicon dioxide-titanium dioxide mixed oxides


A spectacle frame according to the present invention includes a pair of lens hangers each having a lens connector at a distal end thereof, and a pair of fixing barrels for supporting proximal ends of the lens hangers to be rotatable on a leftward/rightward axis, and joined to a brow bar. The fixing barrel has a supporting hole extending leftward/rightward, an outer circumference concentric with the supporting hole, having a predetermined radius of curvature, and an annular groove formed on the outer circumference. The lens hanger which is made of a metallic wire has a shaft portion fit in a rotatable manner into the supporting hole of the fixing barrel, an engagement portion engageable with the annular groove of the fixing barrel, and a spring portion formed between the shaft portion and the engagement portion to elastically bias the engagement portion toward the annular groove.

1. Field of the Invention
The present invention relates to a spectacle frame and a lens hanger removably attached to the spectacle frame.
2. Description of the Related Art
When a wearer of spectacle lenses for accommodating one's eyesight uses sunglasses, polarizing sunglasses, a loupe or aged person's spectacles, it necessary to newly buy exclusively adjusted sunglasses, polarizing sunglasses, loupe or aged person's spectacles. The purchase thereof not only burdens the buyer with the economical load but also troubles him regarding the replacement. Accordingly, in the prior art, there are many proposals wherein additional spectacle lenses such as sunglasses, polarizing sunglasses or a loupe are used while covering the former on the top of the presently used spectacle lenses in the spectacle frame.
In Japanese Unexamined Patent Publication (Kokai) No. 11-264956, subsidiary sunglasses removably attached to a spectacle frame are disclosed. According to this invention, the frame of the subsidiary sunglasses is put into a brow bar or a brace bar to be openable and closable relative to the spectacle frame by the elasticity of spring members incorporated in the subsidiary sunglasses. According to this subsidiary sunglasses, it is possible to use the spectacle lenses alone or together with the subsidiary sunglass if necessary.
The jumping-up type subsidiary sunglasses disclosed by the Japanese Unexamined Patent Publication (Kokai) No. 11-264956 are of a general purpose type usable for various spectacle frames in a relatively wider range. Particularly, those having the openable/closable function, however, are liable to increase their weights due to the incorporation of the spring members or others. Accordingly, there is an inconvenience particularly in recent spectacle frames having a reduced weight in that a sense of incompatibility in design is significant and also a weight balance is no good, whereby the spectacle frame may slip off during the wearing. In addition, the spectacle frame is not so good in wearing sense, has a number of fine parts and is inferior in durability.
When one wearing the spectacles uses a microscope or a telescope, particularly through an eyepiece having a short eye point, it is necessary to remove the spectacles, whereby the operability is often extremely worsened. To eliminate such a trouble, jumping-up type spectacle frames are proposed in Japanese Unexamined Patent Publication (Kokai) No. 10-115811 or others. The jumping-up type spectacle frame disclosed in the Japanese Unexamined Patent Publication (Kokai) No. 10-115811 is capable of opening and closing rims to which spectacle lenses are attached are openable and closable relative to the brow bar of the spectacle frame.
The jumping-up type spectacle frame disclosed in the Japanese Unexamined Patent Publication (Kokai) No. 10-115811 has a structure so that left and right rims are opened or closed while being integral with each other. To stop the rims at an optional rotational position, it is necessary to incorporate a balancer using, for example, torsion coil springs in correspondence to weights of the rims and the lenses or to impart a strong frictional force to the rotational center. The construction incorporating the balancer has a drawback in that the number of parts becomes large to increase the weight thereof and the appearance of the spectacle frame is worsen. On the other hand, in the construction wherein the rotational position of the rims is maintained by the frictional force, it is difficult to jump up the spectacle lenses by a weak force, which deteriorates the operational feeling of the spectacle frame. In addition, it becomes gradually difficult to maintain the jumping-up state of the spectacle lenses due the wearing of the rotational parts. Also, it is necessary to frequently adjust the jumping-up mechanism.


A suspension for a disc drive includes a base plate, a load beam, and a flexure. The flexure includes a metal base member and a circuit member disposed along the metal base member. The circuit member extends along the load beam. The circuit member includes a resin base member formed of a first polyimide, conductors, and a resin cover member formed of a second polyimide. The resin cover member is lower than the resin base member in humidity expansion coefficient.

1. Field of the Invention
The present invention relates to a suspension for a disc drive used in an information processing apparatus, such as a personal computer.
2. Description of the Related Art
A hard disc drive (HDD) is used in an information processing apparatus, such as a personal computer. The HDD includes a magnetic disc that rotates around a spindle, a carriage turnable around a pivot, etc. A suspension for the disc drive is disposed on an arm of the carriage.
The suspension for the disc drive includes a load beam fixed to the carriage, a flexure located overlapping the load beam, etc. A slider is mounted on a tongue portion that is formed on the flexure. The slider is provided with a transducer for reading or writing data.
Flexures of various forms have been put to practical use according to required specifications. As an example of these flexures, there is a flexure with conductors described in Jpn. Pat. Appln. KOKAI Publication No. 2005-183831. The flexure with conductors includes a metal base member formed of a thin stainless steel plate, a resin base member formed of an electrically insulating material, such as polyimide, a plurality of copper conductors, etc. The resin base member is formed on the metal base member. The conductors are formed on the resin base member and covered by a cover member formed of an electrically insulating material, such as polyimide.
A pitchwise inclination of the slider with the tongue portion of the flexure in a free state is called a pitch static attitude in the art. In order to achieve a predetermined performance of the suspension for the disc drive, variation of the pitch static attitude should be minimized.
The pitch static attitude varies depending on various factors. It is generally known that the pitch static attitude may fluctuate owing to, for example, a variation in the machining accuracy of the flexure or a temperature change. Studies by the inventors indicate that a flexure with conductors is more susceptible to humidity changes than one without. In the case of a flexure with conductors in which a photosensitive polyimide is used for a resin cover member of a circuit member, in particular, the pitch static attitude sometimes may considerably vary in sensitive response to humidity changes.


A control device controls an analyzing device or a processing device by using an application performing control for causing a GUI image including a plurality of GUI components to be displayed on a display screen of a display unit. The control device includes: a GUI component designation information receiving unit that receives GUI component designation information used for designating a GUI component among the GUI components; a position information acquiring unit that identifies the GUI component designated on the basis of the GUI component designation information and acquires position information indicating a position of the identified GUI component on the display screen from an operation system; and an emphasizing image display control unit that performs control for causing an image for emphasizing the identified GUI component to be displayed on the display screen on the basis of the position information.

The present invention relates to a control device, and an information storage medium.
As means which receives a user operation in a control device for controlling an analyzing device such as an electronic microscope, a mass spectroscope, an electron probe micro-analyzer or a processing device such as a focus ion beam system, a graphical user interface (GUI) is known. For example, Japanese Patent Application Publication No. 2014-115104 discloses a GUI for a user to instruct the dilution rate of a standard specimen in a mass spectroscope, a GUI for checking whether or not a calibration curve is appropriately produced, and the like.
Since a method of operating an analyzing device or a processing device as mentioned above is complicated, an unskilled user may operate a GUI, while looking at an electronic manual. However, even when the user can know a GUI component to be operated next by referring to the electronic manual, a large number of GUI components are displayed on the displayed screen of a control device. Accordingly, the user has to find the GUI component to be operated next from among the large number of GUI components.

User interface help control device, and information storage medium


An observation-point arranging unit arranges an observation point indicating a portion to be included in a slice area on a positioning image displayed on a display device. A scanning-condition receiving unit receives a specification of a scanning condition including number of movements of a couch on which an object is placed during scanning and a size of the slice area. A slice-area setting unit sets the slice area including the observation point for each position to which the couch is to be moved, based on the observation point and the scanning condition. A scanning unit scans the object multiple times while moving the couch, based on the slice area.

1. Field of the Invention
The present invention relates to a magnetic resonance imaging apparatus and a method of setting a slice area.
2. Description of the Related Art
In a conventional method of setting a slice area for a magnetic resonance imaging apparatus, a tomographic image of an object is taken in advance as a positioning image, an operator sets a slice area for an actual scanning by arranging slice areas with respect to the positioning image displayed on a console (see, for example, JP-A 2003-290171 (KOKAI) or JP-A 2003-290172 (KOKAI)).
A magnetic resonance imaging apparatus generally excites hydrogen nuclei inside an object by irradiating the object placed in a static magnetic field with a radio frequency (RF) wave, and reconstructs an image from magnetic resonance signals emitted by the excitation of the hydrogen nuclei. However, a scan image may be degraded at a position far from the center of the static magnetic field because the static magnetic field becomes nonuniform with increasing distance from the center of the static magnetic field.
For this reason, if a scanning needs to be performed on an object across a wide range, the scanning is performed multiple times by moving a couch in the direction of the body axis of the object. In this case, the slice area needs to be set for each movement of the couch, and when setting the slice area using the positioning image, a rectangular parallelepiped range representing the slice area (hereinafter, "a volume") is arranged to a position of the couch with respect to the positioning image. At this time, the operator arranges the volume in such a manner that a region of interest is included inside the volume by adjusting the position and the orientation inclination in accordance with a body part and a posture of the object.
However, for example, when performing angiography of a lower limb, there is a problem that an operation of setting the volume is cumbersome and complicated, because it is difficult to arrange the volume in such a manner that blood vessels in the region of interest completely fall within the volume. It is because that the angiography of the lower limb requires a wide range scanning, so that the scanning is performed multiple times, and furthermore, the lower limb cannot be stretched to a perfectly straight form and blood vessels inside the lower limb run three-dimensionally.

Magnetic resonance imaging apparatus and method of setting slice-area/slice-volume orientation at each moved couch position


A novel methodology for characterizing and calibrating an entangled photon distribution system is disclosed. The entangled photon distribution system includes at least a source of entangled photon pairs, two photon detectors which detect photons among two channels and a controller. The methodology includes: for at least two different operational setting levels of the source of entangled photon pairs, measuring count rates for photons detected by the two photon detectors, individually and coincidently; fitting the measured individual and coincidence count rate data for the at least two different operational setting levels with theoretical models of detection probability; and determining operational parameters of the system from the fitting. The determined operational parameters of the system include the rate of generated entangled photon pairs by the source, the rates of Raman-scattered photons generated in the first and second channels, respectively, and the efficiency of the two photon detectors, respectively.

Entanglement is a key feature in quantum information science, and provides a resource which can be exploited for secret communications, computation, and enhanced sensing. The creation of entanglement can be achieved using a fourwave mixing source in nonlinear optical media such as optical fibers. Unfortunately, the creation of entanglement in this way is not without noise in the form of Raman-scattered photons which reduce the usefulness of the created entangled photons. To properly characterize such a source of entanglement it is generally necessary to separately measure either the detector efficiencies or the amount of Raman noise in a system and use these as inputs into a characterization model.
Entangled photon sources are required for quantum networking applications. Historically, these entangled photon sources generated entangled photon pairs using various bulk crystals (χ(2) nonlinearity). However, entangled sources using four-wave-mixing (FWM) in the zero-dispersion region of optical fibers (χ(3) nonlinearity) have recently been developed as disclosed in the publication M. Fiorentino, P. L. Voss, J. E. Sharping, and P. Kumar, "All-fiber photon-pair source for quantum communications," IEEE Photon. Technol. Lett. 14, 983-985 (2002). These sources have the benefit of the generated signal and idler photons being inherently fiber-based. This allows low-loss coupling to existing fiber networks for long distance distribution of entanglement. However, Raman-scattered noise photons are generated in addition to the entangled pairs with a fiber-based source, and steps must be taken to reduce their effect on the system's performance. Likewise, the Raman-scattered photons result in additional difficulties when characterizing the source and its detectors.
In order to fully characterize an entangled photon source and detection system, the photon generation rates (FWM pairs and Raman-scattered photons), channel transmission, and detector efficiencies must be known.
The proper use of an entangled photon distribution system necessitates a calibration procedure, which entails the determination of the photon generation rates (both FWM signal-idler pairs and Raman-scattered noise photons) and detector efficiencies (which are less than 100% for telecom band InGaAs avalanche photodetectors). The difficulty in assessing these efficiencies lies in the absence of deterministic single photon sources. The historic solution proposed by D. N. Klyshko, "Use of two-photon light for absolute calibration of photoelectric detectors," Sov. J. Quantum Electron. 10, 1112 (1980) utilizes a photon pair source to accurately determine the efficiency of single photon detectors (SPDs). SPDs have been very accurately characterized using this method with crystal-based entanglement sources. However, it is difficult to apply this method to fiber-based systems due to the presence of Raman-scattered noise photons. Therefore, the determination of detector efficiencies with a fiber-based source has required additional measurements to quantify the amount of Raman-scattered noise photons that are generated. Likewise, determination of the source parameters (both signal/idler and Raman photon generation rate) requires a calibrated detector in the first place.
There is a need for a convenient method to simultaneously characterize both SPDs and a fiber-based entangled photon source. Particularly, the method should allow an in-situ calibration, which requires no disassembling of the system (i.e. no disconnecting fibers) and no additional equipment.

Methodology for in situ characterizing and calibrating an entangled photon distribution system

The United States of America as represented by the Secretary of the Army


A Semiconductor component that contains AlxGayIn1-x-yAszSb1-z, whereby the parameters x, y, and z are selected such that a bandgap of less than 350 meV is achieved, whereby it features a mesa-structuring and a passivation layer containing AlnGa1-nAsmSb1-m is applied at least partially on at least one lateral surface of the structuring, and the parameter n is selected in the range of 0.4 to 1 and the parameter m in the range of 0 to 1.

1. Field of the Invention
The invention relates to a semiconductor component with a passivation layer and a method for its production. Passivation is understood to mean the coating of flat or structured components such that the electrical properties of the component are not a function of the ambient atmosphere.
2. Discussion of Background Information
The surface of a semiconductor represents a disturbance of the periodic lattice that changes the electrical properties of the semiconductor considerably. This causes the formation of surface states that can be modified by the chemisorption or physisorption of adsorbates. The result is a space-charge zone, the expansion and character of which largely determine the properties of the surface. This exerts an impact onto the position of the Fermi level in the active region of the component and consequently to a dependence of the electrical properties on the ambient atmosphere, e.g., air humidity and/or process chemistry. The consequence of the changing surface states are surface leakage currents that raise the noise level of a semiconductor component. The performance of active components, in particular those made of materials with a small bandgap (e.g., infrared photodiodes), is essentially dependent on the noise contributions. Therefore, an effective passivation is essential in particular for the permanent suppression of surface leakage currents and for the stabilization of the electrical properties of the surface of the component.
Generally, components based on elemental semiconductors such as silicon or germanium and the III-V-semiconductors are passivated by applying a layer of insulator material. Customary materials for this are SiO2, SixNy, or SiOxNy. These are applied by various deposition methods, e.g., low pressure chemical vapor deposition (LPCVD), plasma enhanced chemical vapor deposition (PECVD), or sputtering.
Semiconductor components with a small bandgap, e.g., mercury-cadmium-telluride (MCT) can be conventionally passivated by a material with a larger bandgap, e.g., CdTe. The effect of the passivation rests hereby on the combination of the semiconductor CdTe having a large bandgap (Eg=1.6 eV) with the diode material of the component having a smaller bandgap (Eg<350 meV). As a result, an expansion of the effective bandgap occurs in the region of the diode. This leads to a depletion of the respective minority charge carrier in the border area of the diode and thus to a reduction in the surface leakage currents. The methods and processes for the production as well as the processing of MCT are elaborate, error-prone, and cost-intensive.
Furthermore, semiconductor components with a small bandgap can also be produced on the basis of the alloy AlxGayIn1-x-yAszSb1-z. Depending on the parameters x, y, and z, a bandgap of less than 350 meV can be achieved.
Components with small bandgaps can be produced in particular by application of heterostructures and superlattices of two different alloys, such as, e.g., InAs and Ga1-xInxSb single layers with thicknesses of between 2 nm and 10 nm. However, the passivation of such components has not hitherto been possible in a simple manner.

Semiconductor component containing compound of aluminum, gallium, indium, arsenic, and antimony has mesa structure whose sides have passivation layer of compound of aluminum, gallium, arsenic, and antimony

Fraunhofer-Gesellschaft zur Foerderung der Angewandten Forschung E.V.


A non-toxic fire ant extermination system providing probe injection of scalding water below ground level within a fire ant mound is disclosed. The system includes a propane fueled water heater and water circulating pump capable of heating water in the range of 200 to 210 degrees Fahrenheit and of delivering the same at a flow rate of least three gallons per minute which is effective to eradicate the insects within the core region of a fire ant mound. The injection probe features a cylindrical capture shield which is radially disposed about the probe and adapted for sliding attachment therewith being spring-biased in a downward direction against the surface of the ground during operation thereof to retain the intense heat generated by the process,to capture fire ants emerging from the mound, and to protect the operator from the backflow of scalding water as the treatment proceeds. The injection probe is inserted below ground level and a continuous flow of scalding water is introduced into the mound as the probe is inserted further and slowly withdrawn until the hot water has penetrated throughout the core region of the mound complex. The fire ant extermination system is adaptable for use with any natural source of fresh water by use of a suitable filter system. In the alternative the system is adaptable to any municipal water supply having adequate water pressure in the range of 40 to 60 pounds per square inch.

This invention relates to the extermination of fire ants and, more particularly, to a method and apparatus for treating the same.
Since the importation of the fire ant to this country in the early 1900's, perhaps on shiploads of lumber imported from the insect's home territory in South America, more than 300 million acres of cropland, lawns, recreation areas and other valuable property throughout the entire southern portion of the United States have been infested with many millions of acres being rendered useless.
The United States Department of Agriculture estimates an annual yearly loss to agriculture of several billions of dollars because the imported fire ants consume an extraordinary amount of agriculture products such as soybeans, citris fruit and trees, and potatoes.
Fire ants attack any living thing that invades their established territory surrounding their raised nesting mounds and are known to kill and eat chickens, calves and piglets. In some areas the rapidly spreading ants are crowding out (or killing) other insects, lizards, birds, and small mammals completely destroying natural ecosystems.
The use of chemical pesticides and poison baits to eradicate the insects has raised environmental concerns and resulted in a government ban against chemical treatment of fire ants by conventional methods. The primary problem with pesticides and other poisons is that they not only kill their targets but also most other wildlife including those species of ants and other insects which help to keep the population of the fire ants under control.
Thus, the present invention provides a solution to these problems by utilizing an effective environmentally safe, non-toxic treatment for fire ant control.


The invention provides a chemical-mechanical polishing composition containing a ceria abrasive, one or more nonionic polymers, optionally one or more phosphonic acids, optionally one or more nitrogen-containing zwitterionic compounds, optionally one or more sulfonic acid copolymers, optionally one or more anionic copolymers, optionally one or more polymers comprising quaternary amines, optionally one or more compounds that adjust the pH of the polishing compositions, water, and optionally one or more additives. The invention further provides a method of chemically-mechanically polishing a substrate with the inventive chemical-mechanical polishing composition. Typically, the substrate contains silicon oxide, silicon nitride, and/or polysilicon.

Compositions and methods for planarizing or polishing the surface of a substrate are well known in the art. Polishing compositions (also known as polishing slurries) typically contain an abrasive material in a liquid carrier and are applied to a surface by contacting the surface with a polishing pad saturated with the polishing composition. Typical abrasive materials include silicon dioxide, cerium oxide, aluminum oxide, zirconium oxide, and tin oxide. U.S. Pat. No. 5,527,423, for example, describes a method for chemically-mechanically polishing a metal layer by contacting the surface with a polishing slurry comprising high purity fine metal oxide particles in an aqueous medium. Polishing compositions are typically used in conjunction with polishing pads (e.g., a polishing cloth or disk). Suitable polishing pads are described in, for example, U.S. Pat. Nos. 6,062,968, 6,117.000, and 6,126,532, which disclose the use of sintered polyurethane polishing pads having an open-celled porous network, and U.S. Pat. No. 5,489,233, which discloses the use of solid polishing pads having a surface texture or pattern. Instead of, or in addition, being suspended in the polishing composition, the abrasive material may be incorporated into the polishing pad. U.S. Pat. No. 5,958,794 discloses a fixed abrasive polishing pad.
As a method for isolating elements of a semiconductor device, a great deal of attention is being directed towards a shallow trench isolation (STI) process where a silicon nitride layer is formed on a silicon substrate, shallow trenches are formed via etching or photolithography, and a dielectric layer (e.g., an oxide) is deposited to fill the trenches. Due to variation in the depth of trenches, or lines, formed in this manner, it is typically necessary to deposit al excess of dielectric material on top of the substrate to ensure complete filling of all trenches. The excess dielectric material is then typically removed by a chemical-mechanical planarization process to expose the silicon nitride layer. When the silicon nitride layer is exposed, the largest area of the substrate exposed to the chemical-mechanical polishing composition comprises silicon nitride, which must then be polished to achieve a highly planar and uniform surface.
Generally, past practice has been to emphasize selectivity for oxide polishing in preference to silicon nitride polishing. Thus, the silicon nitride layer has served as a stopping layer during the chemical-mechanical planarization process, as the overall polishing rate decreased upon exposure of the silicon nitride layer. For example, U.S. Pat. No. 6,544,892 and references cited therein describe polishing compositions which provide selectivity of silicon dioxide to silicon nitride. Also, U.S. Pat. No. 6,376,381 describes the use of certain nonionic surfactants to increase the polishing selectivity between silicon oxide and silicon nitride layers.
Recently, selectivity for oxide polishing in preference to polysilicon polishing has also been emphasized. For example, the addition of a series of BRIJ™ and polyethylene oxide surfactants, as well as PLURONIC™ L-64, an ethylene oxide-propylene oxide-ethylene oxide triblock copolymer with an HLB of 15, is purported to increase the polishing selectivity of oxide to polysilicon (see Lee et al., "Effects of Nonionic Surfactants on Oxide-to-Polysilicon Selectivity during Chemical Mechanical Polishing,"J. Electrochem. Soc. 149(8): G477-G481 (2002)). Also, U.S. Pat. No. 6,626,968 purports to obtain polishing selectivity of silicon oxide to polysilicon through the use of a polymer additive having hydrophilic and hydrophobic functional groups selected from polyvinylmethylether, polyethylene glycol, polyoxyethylene 23 lauryl ether, polypropanoic acid, polyacrylic acid, and polyether glycol bis(ether).
The STI substrate is typically polished using a conventional polishing medium and an abrasive-containing polishing slurry. However, polishing STI substrates with conventional polishing media and abrasive-containing polishing slurries has been observed to result in overpolishing of the substrate surface or the formation of recesses in the STI features and other topographical defects such as microscratches on the substrate surface. This phenomenon of overpolishing and forming recesses in the STI features is referred to as dishing. Dishing is also used to refer to overpolishing and forming recesses in other types of features. Dishing is undesirable because dishing of substrate features may detrimentally affect device fabrication by causing failure of isolation of transistors and transistor components from one another, resulting in short-circuits. Additionally, overpolishing of the substrate may also result in oxide loss and exposure of the underlying oxide to damage from polishing or chemical activity, which detrimentally affects device quality and performance.
U.S. Patent Application Publications 2009/0246956, 2009/0221145, 2008/0242091, and 2007/0200089 disclose chemical-mechanical polishing compositions comprising various triazole, tetrazole, indole, and indazole compounds that purportedly provide improved dishing performance.
Despite these polishing compositions and methods, there remains a need in the art for polishing compositions and methods that can provide desirable selectivity of silicon oxide, silicon nitride, and polysilicon and that have suitable removal rates, low defectivity, and suitable dishing performance. The invention provides such a composition and method. These and other advantages of the invention, as well as additional inventive features, will be apparent from the description of the invention provided herein.

CMP compositions selective for oxide and nitride with high removal rate and low defectivity