Recent developments in three-color plasma display panels

This paper describes recent developments in the fabrication of three-color-phosphor plasma display panels that improve both electrical and optical performance. The electro-optical characteristics of panels incorporating a phosphor bar pattern are presented, including the properties of panels fabricated with a black, UV-absorbing material surrounding the phosphors. In addition, processes developed to produce 20 × 20 in plasma panels with 512 × 512 three-color resolution elements at a total line density of 60 per inch are described.     

Electron transport self-shift display using an AC plasma panel

Using an electron transport mechanism, a self-shift display has been successfully implemented on an ac plasma panel providing higher resolution, higher shifting speed, and wider operating margins than previously obtained. The mechanism consists of a unidirectional and efficient transport of a large portion of electrons (generated during the display site discharge) to a neighboring OFF transfer site by a low transverse voltage. The process results in a large wall voltage build-up at the transfer site to switch its state from OFF to ON. The implemented electron transport self-shift display consists of a 7 × 128 site array of an Owens-Illinois 60 lines per inch panel where the 128 columns are driven by a four-phase driver. A resolution of one display site for every two electrodes and a shifting speed better than 600 characters per second have been successfully demonstrated. The ranges of the shifting voltages VDand VTare better than 15 V over a 10-V sustain range. The shifting operation also was successfully demonstrated on an 83 lines per inch panel with good operating margins.     

The differential voltage pen for plasma panels—A light pen substitute

A new hand-held interactive pen for ac plasma panels is described. The pen uses multiple metal plates to detect positional information generated by the regular write/erase voltages in the panel. No optical detector is used. Closed-form field potential equations of a panel line outside the panel are derived. These equations enable the resolution of the pen to be optimized; they are also helpful in pointing out some avoidable troublesome secondary effects. It is shown that a multiple plated probe's resolution is seven times better than that of a single-plate probe. This new pen can achieve resolutions to within 1 cell on panel artworks as dense as 50 lines/cm. Worst case detect time is 100 ms for a one million cell panel. Difficulties and special panel requirement when applied to a panel display product are discussed.     

Write and erase waveforms for high-resolution AC plasma display panels

The successful operation of ac plasma display panels (PDP) depends on the optimization of panel parameters such as chamber gap, gas pressure, line width, and the use of half or full-select cancellation techniques. As resolution increases, however, so does the importance of the write and erase waveforms. A unique set of write and erase waveforms which are specifically designed to optimize the performance of high-resolution PDP's are discussed.     

Infrared laser addressing of media for recording and displaying of high-resolution graphic information

Projection display systems which use a scanned infra-red laser beam to thermally record graphic information on different media may offer a useful alternative to CRT and other display systems. Three different types of thermal-recording projection display systems are reviewed. Laser micromachining of thin bismuth film has proved to be a very simple and efficient way to obtain instant high-quality images which are also permanent. Variable amplitude light pulses produced by an intracavity modulated laser beam were used to write these images. With an average laser power of 20 mW, 8×10 mm²facsimile type continuous-tone images, with a resolution of 1300×2000 resolvable elements, were recorded in 4 s. Thermal writing on liquid crystals offers a unique and simple way to record and display high-quality high-resolution graphic images with the capabilities of fast total or local erase. A CW Nd:YA1G laser was used to write graphic and alphanumeric-type information on cholesteric and smectic-type liquid-crystal light valves. High quality black and white images with a resolution of 2000×2000 picture elements were recorded within 30×30 mm²of liquid-crystal cell frames. With 4 mW of laser power, images were recorded at a rate of 10⁴resolvable elements per second. A contrast ratio of 7:1 was obtained with the cholesteric-type liquid-crystal light valve. The stored image was electrically erased in about 0.1 s. In smectic-type light valves, the contrast ratio was better than 10:1 and local erase was achieved by the application of an electric field while the laser beam locally heated the erased area.     

Reflective liquid crystal television display

A new reflective television display, operating off the air, is described. The display uses the dynamic scattering mode (DSM) in nematic liquid crystals and can be viewed in high-brightness ambients. The liquid crystal cell, 6 to 12 µm thick, was addressed in real time by means of an electron beam using a wire-mosaic faceplate on a demountable cathode ray tube. Two different liquid crystal materials--anasylidene paraamino phenyl acetate (APAPA) and an RCA proprietary room temperature liquid crystal--were tested with similar results except for the difference in operating temperature (82 to 110° C and room temperature, respectively). The resolution of the 3.1-cm-square display was somewhat less than that required for commercial television (∼150 lines), limited by the mosaic structure but not the liquid crystal. Adequate resolution should be achievable in slightly larger displays. The contrast was not optimized (7.5 to 1) but several techniques are available to improve this value to 15 or 20 to 1 as has been demonstrated in static displays. The subjective evaluation of this display points out the attractiveness of reflective television panels; under suitable external illumination the panel has a wide viewing angle (±45° approximately). The current and voltage requirements to achieve the DSM in liquid crystals are such as to raise hopes that an integrated addressing approach suitable for flat television panels can be found.     

Focus reflex modulation of electron guns

High resolution and low drive features have been successfully combined in a new type of electron gun for cathode-ray tubes. The gun has a spot-defining aperture of 0.007 inch upon which emission from a large cathode area is concentrated by a retarding electron lens. This unit modulates the beam by electron reflection, while focusing it upon the aperture ("Focus Reflex Modulation"). Immediately ahead of the aperture, a modulated virtual cathode is formed with an emission capability of over four amperes per square centimeter. A1000-microa beam with a 6° divergence is controlled by a signal of 12 volts centered at ground potential. Highlight brigntness of 250 foot lamberts was read at 17,500 volts, while more than 500 lines were resolved on a television test pattern. In more recent forms of the FRM gun,1600 microa are measured in the screen return, out of1800-microa cathode current. This is 88 per cent over-all transmission, using the same defining aperture (0.007 inch). 18 volts of drive signal will completely modulate the above current.     

A 512-kb flash EEPROM embedded in a 32-b microcontroller

A 512-kb flash EEPROM developed for microcontroller applications is reported. Many process and performance constraints associated with the conventional flash EEPROM have been eliminated through the development of a new flash EEPROM cell and new circuit techniques. Design of the 512-kb flash EEPROM, which is programmable for different array sizes, has been evaluated from 256- and 384-kb arrays embedded in new 32-b microcontrollers. The 512-kb flash EEPROM has incorporated the newly developed source-coupled split-gate (SCSG) flash EEPROM cell, Zener-diode controlled programming voltages, internally generated erase voltage, and a new differential sense amplifier. It has eliminated overerase and program disturb problems without relying on tight process controls and on critical operational sequences and timings, such as intelligent erase, intelligent program, and preprogram before erase. A modular approach was used for chip design to minimize development time and for processing technology to achieve high manufacturability and flexibility     

Canon: more than just concern

A profile is presented of Canon Inc., a Japanese company that has successfully diversified its product line away from the cameras with which it made its name. Among its products are digital color copiers, laser printers, and IC wafer-steppers. Canon, which operates six research centers in Japan plus R&D subsidiaries in the US and Europe, has grabbed 70% of the color printer market and is preparing for the evolution toward a new generation of G4 digital facsimile machines in conjunction with a more advanced integrated-services digital network (ISDN) infrastructure. Canon also has many new camera offerings, as well as a removable magnetooptical disk that offers read write, and erase capability, and can store 256 Mbytes, the equivalent of 6500 pages of text, on a single side     

A new multi-resolution hybrid wavelet for analysis and image compression

Most of the current image- and video-related applications require higher resolution of images and higher data rates during transmission, better compression techniques are constantly being sought after. This paper proposes a new and unique hybrid wavelet technique which has been used for image analysis and compression. The proposed hybrid wavelet combines the properties of existing orthogonal transforms in the most desirable way and also provides for multi-resolution analysis. These wavelets have unique properties that they can be generated for various sizes and types by using different component transforms and varying the number of components at each level of resolution. These hybrid wavelets have been applied to various standard images like Lena (512 × 512), Cameraman (256 × 256) and the values of peak signal to noise ratio (PSNR) obtained are compared with those obtained using some standard existing compression techniques. Considerable improvement in the values of PSNR, as much as 5.95 dB higher than the standard methods, has been observed, which shows that hybrid wavelet gives better compression. Images of various sizes like Scenery (200 × 200), Fruit (375 × 375) and Barbara (112 × 224) have also been compressed using these wavelets to demonstrate their use for different sizes and shapes.     

A true three-dimensional display

A new three-dimensional (3D) display concept is described that employs a random accessed flying spot in a transparent volume of material viewable from any position outside the volume. Arbitrary, true 3D figures may be presented ranging from line to full surface drawings and including alphanumerics. The display has a multicolor capability, continuously variable intensity, and can exhibit fixed or moving objects with good resolution. Display volumes of several cubic feet with high information capacity seem feasible.     

短波红外InGaAs焦平面探测器研究进展

短波红外InGaAs焦平面探测器具有探测率高、均匀性好等优点,在航天遥感、微光夜视、医疗诊断等领域具有广泛应用。近十年来,中国科学院上海技术物理研究所围绕高灵敏度常规波长（0.9～1.7 μm） InGaAs焦平面、延伸波长（1.0～2.5 μm） InGaAs焦平面以及新型多功能InGaAs探测器取得了良好进展。在常规波长InGaAs焦平面方面,从256×1、512×1元等线列向320×256、640×512、4 000×128、1 280×1 024元等多种规格面阵方面发展,室温暗电流密度优于5 nA/cm2,室温峰值探测率优于5×1012 cm·Hz1/2/W。在延伸波长InGaAs探测器方面,发展了高光谱高帧频1 024×256、1 024×512元焦平面,暗电流密度优于10 nA/cm2和峰值探测率优于5×1011 cm·Hz1/2/W@200 K。在新型多功能InGaAs探测器方面,发展了一种可见近红外响应的InGaAs探测器,通过具有阻挡层结构的新型外延材料和片上集成微纳陷光结构,实现0.4～1.7 μm宽谱段响应,研制的320×256、640×512焦平面组件的量子效率达到40%@0.5 m、80%@0.8 m、90%@1.55 m;发展了片上集成亚波长金属光栅的InGaAs偏振探测器,其在0 °、45 °、90 °、135 °的消光比优于20:1。     

Memory array architecture and decoding scheme for 3 V only sectorerasable DINOR flash memory

A memory array architecture and row decoding scheme for a 3 V only DINOR (divided bit line NOR) flash memory has been designed. A new sector organization realizes one word line driver per two word lines, which is conformable to tight word line pitch. A hierarchical negative voltage switching row decoder and a compact source line driver have been developed for 1 K byte sector erase without increasing the chip size. A bit-by-bit programming control and a low threshold voltage detection circuit provide a high speed random access time at low V_cc and a narrow program threshold voltage distribution. A 4 Mb DINOR flash memory test device was fabricated from 0.5 μm, double-layer metal, triple polysilicon, triple well CMOS process. The cell measures 1.8×1.6 μm² and the chip measures 5.8×5.0 mm ². The divided bit line structure realizes a small NOR type memory cell     

Advanced IX projection photolithography

Pattern techniques in the semiconductor industry are driven by the need to improve cost/performance per bit. The key to reducing cost per bit and improving performance is increased density. Tighter photolithography ground rules (smaller images with reduced line width and registration tolerances) are primary sources of increased density. Enhanced ground rules coupled with larger wafers are certain to form the basis for the next generation of VLSI chips. The trend toward tighter ground rules and larger wafers is causing many semiconductor manufacturers to migrate away from IX projection tools, the workhorses of present-day production lines, to step and repeat exposure tools. The higher numerical aperture of step and repeat tools, coupled with chip-by-chip focus, guarantees improved resolution compared to today’s IX projection tools. The price paid for increased numerical aperture is reduced field size and, subsequently, reduced throughput and higher exposure cost per wafer. Ideally, it would be preferable to improve the resolution of the IX projection tool/process to make it competitive with the step and repeat tool, while maintaining the high throughput of IX systems. Effective use of shorter exposure (< 350 nm) wavelengths in IX systems is the key to extending resolution capability.     

A novel self-aligned highly reliable sidewall split-gate flash memory

A self-aligned sidewall split-gate Flash memory cell is fabricated with overerase immunity. Particularly, the sidewall corner of the floating-gate is deliberately rounded to release the electric field lines encountered in the poly-to-poly erase. The unit cell size of 12.7 F/sup 2/ (F is the feature size), formed in a 32-Mb NOR architecture, and the acceptable erase speed of 20 ms for block erase (512 K bits, 16 pages) are quite competitive. Endurance cycles up to 10/sup 5/ confirm the novel cell to be highly reliable as compared with the conventional source-side erase scheme. The bake experiment at 250/spl deg/C before and after program/erase cycles indicates the cell not only free of extrinsic defects in the manufacturing process but also experiencing excellent retention characteristics. Disturb effects during the programming and read-out operations are examined in detail and the operating conditions for disturbs inhibition are readily determined. We eventually elaborate on the differences between the proposed cell structure and existing ones, as well as on the NAND architecture application.     

Developmental solid-state imaging system

A developmental imaging system has been constructed as part of a long-term program to develop a high quality, high performance, all solid-state television camera for NASA. The purpose of the developmental system is to provide a test and demonstration vehicle for solid-state mosaics developed on the program and to obtain limited operational information in a nonlaboratory environment. The system, loosely packaged in an 8½-by-8½-by-10 inch volume including display sweep generator circuits, utilizes commercially available integrated circuit logic cards, discrete FET sampling switches, and a 100-by-128 element mosaic developed on the program. The "camera" provides a dynamic range of approximately five to seven shades of gray and operates on 6 volts at variable frame rates between 6 and 60 frames per second at light levels of 0.1 to 1 foot-candle, respectively. As of March, 1968, the system had been in operation for approximately one year without failure. This imaging system exhibits frame integration sensitivity due to storage of light-generated charge carriers in each phototransistor's collector-base depletion layer during the periods between its readout sampling. Fabrication of the sensor matrix and mechanization of the interrogation system for image readout from the mosaic are described. Considerations affecting imaging resolution, spectral response, responsivity dynamic range, and quantum efficiency are discussed.     

An experimental 4 Mb flash EEPROM with sector erase

A 512K×8 flash EEPROM (electrically erasable programmable ROM) which operates from a single 5-V supply was designed and fabricated. A double-poly, single-metal CMOS process with a minimum feature size of 0.9 μm was developed to manufacture the test vehicle, which resulted in a die size of 95 mm². The storage cell is 8.64 μm² and consists of a one-transistor cell that uses a remote, scalable, tunnel diode for programming and erasing by Fowler-Nordheim tunneling. Process high-voltage requirements are relaxed by utilizing circuit techniques to alleviate the burden of high voltages. A segmented architecture provides the flexibility to erase any one sector (16 kB) or the entire chip during one cycle by an erase algorithm. The memory can be programmed one byte at a time, or the internal bit-line latches can be used to program a 256-B page in one cycle. A programming time of 10 ms is typical, which results in a write time of 40 μs/B during page programming. The chip features an access time of 90 ns     

3.5‐Inch QCIF AMOLED Panels with Ultra‐low‐Temperature Polycrystalline Silicon Thin Film Transistor on Plastic Substrate

In this paper, we describe the fabrication of 3.5‐inch QCIF active matrix organic light emitting display (AMOLED) panels driven by thin film transistors, which are produced by an ultra‐low‐temperature polycrystalline silicon process on plastic substrates. The over all processing scheme and technical details are discussed from the viewpoint of mechanical stability and display performance. New ideas, such as a new triple‐layered metal gate structure to lower leakage current and organic layers for electrical passivation and stress reduction are highlighted. The operation of a 3.5‐inch QCIF AMOLED is also demonstrated.     

Correction of deflection-aberrations by analog computer

For wide-angle deflection (±25°) of microspot tubes (spot size-8 microns), dynamic correction of focal length (DCF) alone is no longer capable of conserving resolution. It is found, however, that complete recovery of ultra-high resolution (3000 lines per inch) is practical by adding dynamic correction of astigmatism (DCA) to DCF. The laws of error distribution on the tube face are found to be quadratic functions of position coordinatesxandy. Dynamic correction thus requires an ideal product generator that obeys the associative law of multiplication out to large amplitudes. A special beam-deflection type of computer tube has been developed. It operates on the principle of deflecting a square beam across a quadrantal target. An analog computer using three of these "roving-square tubes" (RST's) generates all three dynamic corrections as required by DCF and DCA. Photographs of deflected television microimages show the effectiveness of this analog computer in presenting approximately 9000 spot diameters, or 80 million dots, within a 3-inch square.     

Charge transport in an AC plasma panel

A transverse voltage applied between a display cellDand a transfer cellTon a standard 60 lines/inch ac plasma panel can simultaneously cause a previously ON cellDto fire and transport a large amount of electrons from cellDtoward cellT. The same transverse voltage combines with the voltage due to transported electrons to produce subsequent discharges which, initiated near cellT, grow rapidly as they propagate along the row toward cellD. A voltage pulse (≃sustain pulse), applied to cellT, will combine with the local row wall voltage to produce another sequence of discharges along the row. These discharges, initiated near cellD, gain intensity as they spread toward cellT. This dynamic process results in a large and controllable charge transfer between the display cellDand the transfer cellT, a key mechanism for shift address display. By reversing the polarity of the transverse voltage, ions also can be transported, but ion transport produces smaller charge transfer.