2英寸高均匀性GaAs多层外延材料

用法国进口的ＧａＡｓＶＰＥ设备，采用ＡｓＣｌ）３／Ｈ＿２／Ｇａ体系，以ＳｎＣｌ＿４ｌ／ＡｓＣｌ＿３为掺杂液，生长了２英寸多层ＧａＡｓ外延材料，自行设计了反应器的热场分布，在反应器中增加了合适的搅拌器，用以改变反应器中气体流动情况。ＧａＡｓ外延层的浓度均匀性与厚度均匀性均小于５％。浓度均匀性的最佳值为３．７％，厚度均匀性的最佳值为１．５％，当外延层载流子浓度为１．９×１０￣（１７）ｃｍ￣（－３）时，室温迁移率达到４３９０ｃｍ￣２／Ｖ·ｓ。     

WB系列砷化镓变容二极管

ＷＢ系列砷化镓变容二极管ＷＢＳｅｒｉａｌＧａＡｓＶａｒａｃｔｏｒｓＧａＡｓ变容管具有优良的微波性能，已广泛应用于微波电路中。从７０年代起，南京电子器件研究所开始研制ＧａＡｓ变容管，目前，产品已形成系列化，具有电性能好，可靠性高等优点，在国内得到广泛应...     

C波段GaAs FET VCO设计的一种方法

在小信号Ｓ参数基础上，提出了一种宽带优化方法，设计了宽调谐、低相噪ＧａＡｓＦＥＴＶＣＯ。用该方法设计的Ｃ波段ＧａＡｓＦＥＴＶＣＯ用变容二级管调谐，其电压调谐范围在０～１５Ｖ，在调谐带宽为５００ＭＨｚ范围内ＶＣＯ的调谐线性度为１：１．５，带内相位噪声优于－８２ｄＢｃ（偏离１００ｋＨｚ处）输出功率大于２０ｍＷ，功率起伏小于±１ｄＢ。     

硅基GaAs／GaAlAs平面光波导的研究

分析了金属有机化合物化学气相淀积（ＭＯＣＶＤ）ＧａＡｓ／ＧａＡｓＡｌ／ＧａＡｓ／Ｓｉ材料结构的性能，用ＭＯＣＶＤ法地硅衬底上生长了ＧａＡｓ／ＧａＡｓＡｌ／ＧａＡｓ材料，并用这种材料制备了平面光波导样品，测定了１．３μｍ，单模激光的传输损耗小于０．６５ｄＢ／ｃｍ。     

2英寸GaAs快速热退火技术研究

为配合２０００门ＧａＡｓ超高速门阵列及ＧａＡｓ超高速分频器等２英寸ＧａＡｓ工艺技术研究，开展了２英寸ＧａＡｓ快速热退火技术研究。做出了阈值电压为０～０．２Ｖ，跨导大于１００ｍＳ／ｍｍ的Ｅ型ＧａＡｓＭＥＳＦＥＴ和夹断电压为－０．４～－０．６Ｖ，跨导大于１００ｍＳ／ｍｍ的低阈值Ｄ型ＧａＡｓＭＥＳＦＥＴ。     

用MOCVD在非平面衬底上生长的量子阱、量子线及其光学性质

本文报道在６５０℃的衬底温度下实现了ＭＯＣＶＤ在（１００）面和（１１１）面上生长ＧａＡｓ与Ａｌ０．４Ｇａ０．６Ａｓ的不同的选择性．这一衬底温度比国际上以前报道的要低，对制作适于光电器件的ＧａＡｓ／ＡｌＧａＡｓ量子阱层比较有利．用此技术，在ＧａＡｓ非平面衬底上生长了ＧａＡｓ／Ａｌ０．４Ｇａ０．６Ａｓ量子阱，并用扫描电镜、低温光致发光谱以及偏振激发的光反射率谱技术进行了研究．结果不仅证明了ＭＯＣＶＤ外延生长ＧａＡｓ和Ａｌ０．４Ｇａ０．６Ａｓ的独特选择性，也证明了在Ｖ字形沟槽底形成了量子线．     

2英寸GaAs快速热退火技术研究

为配合２０００门ＧａＡｓ超高速门列及ＧａＡｓ超高速分频器等２英寸ＧａＡｓ工艺技术研究，开展了２英寸ＧａＡｓ快速热退火技术研究，做出了阈值电压为０～０．２Ｖ，跨导大于１００ｍＳ／ｍｍ的Ｅ型ＧａＡｓＭＥＳＦＥＴ和夹断电压为－０．４～－０．６Ｖ，跨导大于１００ｍＳ／ｍｍ的低阈值Ｄ型ＧａＡｓＭＥＳＦＥＴ。     

GaAs表面及AlxGa1—xAs／GaAsHBT外基区表面（NH4）2S／SiNx钝化工艺研究

分析了ＡｌｘＧａ１－ｘＡｓ／ＧａＡｓＨＢＴ外基区表面复合电流及外基区复面复合速度对直接增益的影响，用光致发光（ＰＬ）谱和Ａｌ／ＳｉＮｘ－Ｓ／ＧａＡｓＭＩＳ结构ＣＶ特性，研究了ＧａＡｓ表面（ＮＨ４）２Ｓ／ＳｉＮｘ钝化工艺的效果及其稳定性。结果表明，ＥＣＲ－ＣＶＤ淀积ＳｉＮｘ覆盖并在Ｎ２气氛中退火有助于改善ＧａＡｓ表面硫钝化效果的稳定性，在此基础上形成了一套包括（ＮＨ４）２Ｓ处理，ＳｉＮｘＥＣＲ－ＣＶ     

用MOCVD在非平面衬底上生长的量子阱,量子线及其光学性质

本文报道在６５０℃的衬底温度下实现了ＭＯＣＶＤ在（１００）面和（１１１）面上生长ＧａＡｓ与Ａｌ０．４Ｇａ０．６Ａｓ的不同选择性。这一衬底温度比国际上以前报道的要低，对制作适于光电器件的ＧａＡｓ／ＡｌＧａＡｓ量子阱层比较有利。用此技术，在ＧａＡｓ非平面衬底上生长了ＧａＡｓ／Ａｌ０．４Ｇａ０．６Ａｓ量子阱，并用扫描电镜、低温光致发光谱及偏振激发的光反射率谱技术进行了研究。结果不仅证明了ＭＣＣＶＤ外延生     

固体C_(60)/p-GaAs异质结的整流特性和界面电子态

我们将Ｃ６０膜淀积在ｐ－ＧａＡｓ〈１００〉衬底上，做成了固体Ｃ６０／ｐ－ＧａＡｓ异质结并对其电学性质做了研究．异质结的理想因子接近于１，在偏压为±１Ｖ时，其整流比大于１０６倍．在正向偏压固定的情况下，结电流的对数与温度倒数成线性函数关系，从关系中求出异质结有效势垒高度为０．６３ｅＶ．用深能级瞬态谱（ＤＬＴＳ）技术在Ｃ６０／ｐ－ＧａＡｓ界面上观测到一个空穴陷阱，其能级为ＧａＡｓ价带之上０．４５ｅＶ，密度为２．４×１０１１／ｃｍ２．这样少的界面态存在于Ｃ６０／ｐ－ＧａＡｓ界面上可能意味着Ｃ６０膜对ＧａＡｓ表面     

Quantum barrier varactor for coplanar waveguide applications

A quantum barrier varactor with a GaAs/AlGaAs/GaAs structure embedded in a coplanar waveguide has been fabricated. The configuration in the coplanar waveguide improves frequency-tripler performance by using a harmonic load-pull technique     

Varactor Controlled Gunn Oscillator at W-Band

This paper describes the experimental circuit and measured performance of varactor tuned Gunn oscillator at W-band. The power output of 12.5 dBm has been achieved when packaged GaAs Gunn diode is used. Linear frequency excursion of 150 MHz with power variation of 1 dB has been observed when varactor was given reverse bias from 0 to 20 volts. GaAs hyperabrupt varactor is used in parallel to gunn diode at a distance of odd multiple of λg/2 in waveguide channel.     

“P~+-N结正向势垒电容异常变化”变容管模型的最佳化

用计算机辅助设计,给出P~+-N结正向势垒电容异常变化的变容管模型的最佳值解。据此研制的参放变容管性能为:γ[0.5V,-4V]=0.20～0.27,M=110～160。使用该器件的4GHz常温参放,噪声温度低达35K。     

A Millimeter-Wave Quadruple and an Up-Converter Using Planar-Diffused Gallium Arsenide Varactor Diodes

A millimeter-wave quadruple, employing planar-diffused GaAs varactor diodes and a tuned second-harmonic idler circuit, is described. This quadruple operated at an output frequency of 50.4 GHz, produced a maximum power output greater than 13 mW, and exhibited a maximum overall conversion efficiency of 12 percent. 2) A millimeter-wave up-converter using similar diffused GaAs diodes has been operated successfully. The input was at 1.3 GHz, the output at 51.7 GHz, and the local oscillator power was supplied at 50.4 GHz. The minimum observed overall conversion loss, 50.4 to 51.7 GHz, was about 2.5 dB at an output power between 1 and 3 mW. 3) The performance of these devices is described as a function of the parameters of the diodes employed, and a comparison of the performance of diffused-junction and Schottky-barrier diodes (of comparable quality) in the two circuits is discussed. 4) The fabrication and characterization of the planar-diffused gallium arsenide varactor diodes used in these circuits is described; zero-bias cutoff frequencies to values in excess of 2000 GHz were achieved.     

一种基于复合左右手传输线结构的模拟移相器

基于0.25 μm GaAs pHEMT工艺设计了一种工作在Ku波段的可调谐模拟移相器。该移相器采用集总参数型复合左右手传输线(CRLH-TL)拓扑结构实现相移网络,并利用可变电容结构进行相位调谐。为了解决端口失配问题,插入了共源共栅缓冲器来增加隔离度,并中和无源器件带来的损耗。电路采用统一的偏置电压来控制所有变容结构,简化了电路结构。仿真结果表明,该移相器在工作频率内的相移可调谐范围大于90°,在电源电压为1.5 V下,直流功耗为63.3 mW,平均增益大于8.5 dB,幅度波动小于5 dB。     

An electrically and optically gate-controlled Schottky/2DEGvaractor

A novel gate-controlled varactor is reported. The three-terminal varactor is a modulation-doped heterostructure of AlGaAs/GaAs with two Schottky contacts directly made to a two-dimensional electron gas (2DEG). The third, gate, contact is formed from highly doped n⁺ GaAs material to allow an open optical window that can be used for optical gating and mixing. Structure capacitance is less than 1 pF and a change of more than 30% from the zero bias capacitance is observed with the applied gate voltage. The capacitance also increases proportionally with applied light and inversely with the terminal voltage     

Gate controlled 2-DEG varactor for VCO applications in microwave circuits

A novel gate controlled Schottky diode varactor is introduced. The three-terminal varactor is a modulation-doped heterostructure of AlGaAs/GaAs with two Schottky contacts, similar to a metal–semiconductor–metal (MSM) diode. Schottky metal contacts are made to a two-dimensional electron gas (2-DEG). The third contact, the gate contact is formed from highly doped n⁺ GaAs material to allow an open optical window that can be used for optical gating and mixing. Structure capacitance is less than 1 PF and a change of more than 30% from the zero bias capacitance is observed with the applied gate voltage. On the basis of our quasi two-dimensional C–V model, the layer structure and device dimensions can be optimized and scaled to cover a wide range of operations in the microwave and millimeter wave regimes.     

Physical equivalent circuit model for planar Schottky varactordiode

A physical equivalent circuit model for the planar GaAs Schottky varactor diode is presented. The model takes into account the distributed resistance and capacitance of the active layer, the sidewall capacitance, and the parasitic resistances and accurately accounts for the high series resistance observed near the pinch-off voltage. The dependence of the maximum series resistance on varactor size, frequency, and doping profile has been theoretically investigated, and the results agree well with experimental data. The proposed model can be easily used for optimization of planar Schottky varactor diodes with regard to broadband monolithic VCO constraints     

A 15-GHz monolithic low-phase-noise VCO using AlGaAs/GaAs HBTtechnology

A 15-GHz fully monolithic low-phase-noise VCO MMIC fabricated without an external tuning element using an AlGaAs/GaAs HBT technology was developed. An HBT and a variable capacitance diode or varactor were fabricated in an MMIC chip using-standard HBT IC process. A tuning range of about 600 MHz was obtained with varying control voltage from 0 to 4 V with an output power of more than -4 dBm. The low phase noise for an offset frequency of 100 kHz of -85 dBc/Hz was measured at a frequency of 15.6 GHz     

W-band monolithic frequency doubler using vertical GaAs varactor diode with n/sup +/ buried layer

A W-band monolithic frequency doubler was designed and fabricated using a vertical GaAs varactor diode that has an n/sup +/ buried layer and uses a mesa isolation process. An output power of 30 mW was obtained from this chip at 93 GHz with a conversation efficiency of 12%. This is believed to be the first reported W-band monolithic varactor diode frequency doubler.<>