小型CRT—LCLV组合器件

选用１英雨阴极射线管和液晶光阀研制成直径１英寸的ＣＲＴ－ＬＣＬＶ组合器件，介绍了组合器件的工作原理、制作工艺和性能指标，并给出了在小型光学相关器上的应用实例。     

国外消息

国外消息▲取代ＣＲＴ的１４英寸ＴＦＴ┐ＬＣＤ监视器韩国三星电子有限公司研制出的１４英寸薄膜晶体管液晶监视器（ＴＦＴ－ＬＣＤ），可取代一般ＣＲＴ。它的厚度仅５ｃｍ，该小型化监视器的重量为３ｋｇ，约为常规ＣＲＴ监视器的１／１０。新监视器最大清晰度为１０２...     

液晶显示器的宽视角技术

液晶显示器的飞速发展已经影响到了人类生活的许多方面,特别是近年来,由于笔记本电脑的发展,液晶显示屏幕尺寸由最初的１０．４英寸发展到目前人们广泛使用的１４．１英寸、另外用于台式电脑和工作站的液晶显示器也在侵蚀着阴极射线管（ＣＲＴ）的市场,目前屏幕尺寸主要有１５英寸、１６．１英寸、１８英寸以及更大尺寸的监视器,大有取代ＣＲＴ监视器的趋势。随着屏幕尺寸的增大,液晶显示器一个突出的问题就是其视角的狭窄及视角方向的不均匀性。这也是ＬＣＤ取代ＣＲＴ的一个最大障碍。目前已经提出了几种方法,较好地解决了ＬＣＤ的…     

基于数字微镜的数字光处理技术

无论是计算机还是电视机,目前主要都使用阴极射线管（ＣＲＴ）显示器。现在液晶显示器（ＬＣＤ）也已进入计算机和电视机领域,主要用在笔记本电脑和便携式电视机。随着大屏幕、高清晰度电视的发展,ＣＲＴ和ＬＣＤ越来越不能适应新的要求,一种基于数字微镜（ＤｉｇｉｔａｌＭｉｃｒｏ－ｍｉｒｒｏｒＤｅｖｉｃｅ－ＤＭＤ）的数字光路处理技术（ＤｉｇｉｔａｌＬｉｇｈｔＰｒｏｃｅｓｓｉｎｇ,ＤＬＰ）已经用于制造大屏幕显示器（≥３２英寸）和多媒体投影机,它具有高亮度、大屏幕、高清晰度的优良特性。音频数字化己有１０多年历史了,…     

21世纪——平板显示的世纪

平板显示器（ＦＰＤ）与ＣＲＴ（阴极射线管）显示器相比,具有身簿、轻量、功耗小、辐射低、没有闪烁、有利于人体健康等优点,近年得到了迅速发展,大有取代ＣＲＴ之势,因此,２１世纪被称为是液晶的世纪。市场展示美好平板显示器的主要代表液晶显示器（ＬＣＤ）,不断克服价格过高的应用障碍,２０００年世界市场一举成长了２４．３％,达１９６亿美元（同年ＣＲＴ为３１０亿美元）。随着监视器、笔记本电脑市场成长,中大尺寸（８．４英寸以上）ＬＣＤ需求逐年增长,加上中小尺寸（一般认为６～８英寸为中型,２～３英寸为小型）应用市…     

CRT力扛LCD拼争

ＣＲＴ力扛ＬＣＤ拼争１９９８年日本的监视器市场上,ＣＲＴ型仍占主流,但是ＬＣＤ凭借自身优势,正不断扩大市场占有率。ＣＲＴ监视器包括１５、１７、１９和２１英寸各型,目前１７英寸占市场的６０％、１５英寸３０％、１９和２０英寸合占１０％。ＣＲＴ价格下落很快...     

索尼公司开发新型5．6英寸多晶硅TFT－LCD模块

索尼公司开发新型５．６英寸多晶硅ＴＦＴ－ＬＣＤ模块日本索尼公司已开发成功内置驱动电路的新型５．６英寸多晶硅（Ｐ－Ｓｉ）彩色薄膜晶体管液晶显示（ＴＦＴ－ＬＣＤ）模块。与非晶硅（ａ－Ｓｉ）ＴＦＴ—ＬＣＤ模块相比，它有两个突出优点：其一是每个象素上的ＴＦＴ...     

液晶技术走向何方

液晶技术仍将迅速发展。一方面向高清晰度方向发展,在突破ＸＧＡ模式之后,努力向ＨＤＴＶ的２０００线清晰度迈进;另一方面向大屏幕化发展,在目前１５英寸商品化后,将会尽快将２１英寸商品化;此外,液晶技术和等离子ＰＤＰ彩色显示器件的结合将揉合双又方的优点几年后将会出现商品化的 ４０英寸以上的液晶ＰＤＰ,在超大屏幕高清晰度显示器件方面成为ＰＤＰ、ＣＲＴ的有力竞争者。 技术方向 １、低温Ｐｏ－ＳｉＴＦＴ 一般ＴＦＴ驱动电路的实际装载方法为ＴＡＢ—ＣＯＧ－ＭＬ１,它最终将走向驱动电路和液晶板的一体化。为达到这一目…     

如何克服CRT高压在视频动态作用下的不稳定性

１ 传统ＣＲＴ高压不稳的原因ＣＲＴ即阴极射线管（ｃａｔｈｏｄｅ ｒａｙ ｔｕｂｅ）,电子物理学上泛指示波管、显像管等电子束器件,广泛应用于显示领域,在三大显示器件（ＣＲＴ,ＬＣＤ,ＰＤＰ）中,ＣＲＴ技术最为成熟,特别是计算机领域,ＣＲＴ几乎就是计算机显示器的代名词。大家知道,在ＣＲＴ中,为了使电子束在屏幕上扫描形成光栅,必须具备两个条件：第一个条件是要有足够高的阳极电压（高压）,以产生强大电场使电子束加速,获得轰击屏幕的足够动能;第二个条件是要有一个受扫描电流控制使电子束偏转的偏转磁场。因此,电子…     

荷兰SMART舰载三坐标雷达

荷兰ＳＭＡＲＴ舰载三坐标雷达荷兰信号设备公司研制的舰载多波束目标搜索雷达（ＳＭＡＲＴ）是高性能三坐标雷达，有两种型号，即ＳＭＡＲＴ－Ｓ和ＳＭＡＲＴ－Ｌ，其性能指标见表１ＳＭＡＲＴ－Ｓ为中近程搜索雷达，是舰载武器系统的主探测设备，能对付０．１ｍ￣２、３...     

Fabrication of broad-area laser diodes on a three-inch wafer by asolid-phase diffusion method

We have developed extremely uniform Zn diffusion on a three-inch GaAs-AlGaAs QW laser wafer by an open tube solid-phase diffusion technique and have applied it to fabrication of broad-area laser diodes (LD's) for the first time using 3-inch full-wafer processing. Excellent uniformity of device characteristics have been obtained on a 3-inch wafer; threshold current distribution along the radial direction of a wafer is 356.2±8.3 mA (1σ), emission wavelength is 879.7±0.6 nm (1σ). Such high uniformity is caused by not only uniform Zn diffusion but also uniform epitaxial layer thickness over a three-inch wafer     

Relationship Between Basal Plane Dislocation Distribution and Local Basal Plane Bending in PVT-Grown 4H-SiC Crystals

The inhomogeneous distributions of basal plane dislocations (BPDs) in PVT-grown 4H-SiC crystal boule due to internal stresses cause lattice plane bending, which strongly affect SiC-based device fabrication. The relationship between BPDs and local basal plane bending in 6-inch 4H-SiC substrates has been investigated. Synchrotron monochromatic beam x-ray topography (SMBXT) imaging shows black and white contrast of BPDs with Burgers vectors of opposite signs based on the principle of ray tracing. We have evaluated the net difference of BPDs with black and white contrast along both [11$$ \bar{2}$$0] and [1$$ \bar{1}$$00] radial directions on the Si face across multiple 6-inch diameter 4H-SiC substrates sliced from the same and different boules and predicted the nature (concave/convex) and amount of bending of the basal plane in these wafers. Line scans of 0008 reflection using high resolution x-ray diffractometry (HRXRD) has been carried out along the two directions to verify the nature of bending in these wafers. Results show quite different bending behavior along [11$$ \bar{2} $$0] and [1$$ \bar{1}$$00] directions, indicating that the Si face of 6-inch substrates creates non-isotropic bending on the basal plane. These observations are correlated quite well with net BPD density analysis. The physical shapes of the wafers were also measured to be not flat due to the surface effect. Quantitative analysis of the degree of basal plane bending based on the SMBXT data was carried out and found to be correlating well with the measured tilt angle from HRXRD. Existence of a high stress center was observed in one of the 6-inch wafers resulting in severe bending which is associated with both large bending angles and abrupt changes in lattice constants a and c.     

CO2transverse-discharge lasers

A parametric study has been undertaken to determine the gain characteristics of flowing CO2-N2-He lasers employing a transverse-discharge configuration. Unlike conventional cylindrical discharge tubes, in this device the gas-flow and electrical-discharge paths lie perpendicular to the optical axis. Box lasers with various aspect ratios and electrode configurations were evaluated. The gain exhibited an inverse dependence upon the height of the box laser. The axial gain in the Faraday dark space is lower than in the region of the positive column, decreasing monotonically to zero at the cathode. The character of the axial gain profile is significantly changed by a reversal in the direction of gas flow relative to the polarity of the discharge. For a volumetric gas flow of 0.3 scfm, a peak gain of 3.4 dB/m was attained with a box laser characterized by 1/2-inch height, an 8:1 aspect ratio, and a 1-inch adjacent electrode spacing. Power output data are presented for a box laser employing a folded optical resonator.     

CW three-terminal GaAs oscillator

Three-terminal GaAs devices have oscillated coherently at frequencies between 60 MHz and 2500 MHz. Continuous power outputs at room temperature are generally less than 1 mW. Typical units are fabricated from GaAs p-n diodes by sawing into the n side with an 0.0005- or 0.001-inch tungsten wire to a depth close to the depletion region. The resultant device has an n contact on either side of the cut and one control contact on the p region. At a threshold bias field of approximately 4 kV/cm in the narrow neck between the sawcut and the depletion region, coherent microwave or submicrowave oscillations commence. The frequency of oscillation is primarily a function of external circuitry and device size, but can also be controlled by a bias applied to the p electrode.     

Vitesse semiconductor joins the southwest stampede

The vanguard merchant GaAs device supplier's expansion to a 6-inch process fab in Colorado Springs represents more than the 2.2 times as many die per wafer capability that allows Vitesse's GaAs to compete evenly with BiCMOS and 0.35 μm CMOS. The new fab also creates enticing opportunities for Vitesse employees in the more affordable and congenial Southwest USA.     

An L-Band Loop-Type Coupler (Correspondence)

The design of loop couplers for various loop length has been reported by Lombardini, Schwartz and Kelly. This device is useful for many applications as the over-all length can be held to about 6 inches, whereas a com-parable multihole coupler must be on the order of several feet long. The loop-type device couples a TE/sub 10/ waveguide mode from a RG-69/U to a TEM mode in a 3/8-inch coaxial line. A comb-type coupler, for coupling a coaxial line to TE/sub I0/ waveguide, was reported by Lombardini and Schwartz. This device made use of a multiple-capacitive probe situated in a longitudinal slot in the top wall of the waveguide.     

Characteristics of new dielectric isolation wafers for high voltagepower IC's by single-Si poly-Si direct bonding (SPSDB) technique

Physical and mechanical characteristics of a new DI (Dielectric Isolation) wafer based on a single-Si poly-Si direct bonding (SPSDB) technique were investigated to reduce wafer warpage, increase wafer size and decrease minimum device patterning size. Developed SPSDB wafers of 5-inch size had unchanging warpage height and high bonding strength. When SPSDB wafers were bonded at 1100°C for 2 h, the latter property was comparable to that of the thermal oxidizing layer interface     

Current status of large-area MOVPE growth of HgCdTe device heterostructures for infrared focal plane arrays

This paper reviews the current status of the growth of fully doped HgCdTe (MCT) devices by metalorganic vapor phase epitaxy (MOVPE). The current reactor system has been developed to produce 3-inch diameter epitaxial layers compatible with slice-scale processing. The new reactor system has achieved routine epitaxial growth of MCT with good morphology onto both gallium arsenide (GaAs) and GaAs on silicon (Si) wafers that were oriented (2–8°) off (100) orientation. The density of surface defects (so-called “hillocks”), typical of MOVPE growth on such orientation substrates, has been reduced to <5 cm⁻² at a sufficient yield to make the production of low cluster defect 2D arrays possible. Alternative growth experiments onto cadmium telluride (CdTe) on Si substrates with (211)B orientation have also been performed to investigate their usefulness for infrared focal plane array (IRFPA) applications. Si substrates give better thermal expansion match to the read out Si circuits (ROIC). The horizontal reactor cell design has a graphite susceptor with a rotating platen capable of using substrates up to 4-inch diameter. Work, however, has concentrated on 3-inch diameter GaAs and GaAs on Si wafers substrates in the reactor, and these reproducibly demonstrated good compositional and thickness uniformity. Cut-off wavelength and thickness uniformity maps showed that there was sufficient uniformity to produce twelve sites of large format 2D arrays (640×512 diodes on 24-μm pitch) per slice. Minority carrier lifetimes in heterostructures is an important parameter and some factors affecting this are discussed, with special emphasis on As-doped material grown under various growth conditions in an attempt to reduce Shockley-Read (S-R) trap densities. New data are presented on trap densities and theoretical fitting of lifetimes in MOVPE material. Fully doped heterostructures have been grown to investigate the device performance in the 3–5 μm medium-wave IR (MWIR) band and 8–12 μm long-wave IR (LWIR). These layers have been fabricated into mesa arrays and then indium-bumped onto Si multiplexers. A summary of the 80-K device results shows that state-of-the-art device performance has been demonstrated in MOVPE-grown device structures.     

Operational Improvements in Image Orthicon Camera Equipment

A modern broadcast TV Camera adaptable for use with either 3-inch or 4?-inch image orthicon tubes is described. Circuit and mechanical innovations are discussed which result in improved stability and reliability. Simplified operation and maintenance of the camera are emphasized.     

Halogen lamp annealing of GaAs for MESFET fabrication

Incoherent light from high-intensity halogen lamps was used for capless annealing of 2-inch GaAs wafers following silicon ion implantation. Fabrication of depletion mode MESFETs on the annealed wafers was used to study the DC characteristics and uniformity achieved with this annealing method. An average mutual transconductance of 110 mS/mm was obtained with MESFET fabricated wafers which were uniformly implanted at 5 × 1012 cm?2 with Si+ at 80 keV and subsequently annealed at 900°C for 2 s. The carrier concentration profiles obtained with this method are shown to be sharper than those obtained with furnace annealed wafers, which in turn results in a sharper device pinch-off voltage.