平面型RTD及其MOBILE的设计与研制

鉴于已报道的平面共振遂穿二极管(PRTD)存在的缺点,文中提出了一种新的平面RTD器件结构.以n+ GaAs代替半绝缘GaAs衬底,利用硼离子注入产生的非晶化作为RTD器件的电隔离,成功设计研制平面型RTD和由其构成的单-双稳转换逻辑单元,此种结构可适用于以输出端作为公用端的所有电路.     

GaAs基共振隧穿二极管的研究

对GaAs基共振隧穿二极管(RTD)进行了研究,首先用分子束外延(MBE)方法进行AlAs/GaAs/InGaAs双势垒单势阱材料结构的生长.接着用常温光致荧光(PL)方法对结构材料进行了测试分析,其结果显示,较好的外延结构材料的PL谱线半峰宽达到62.6 nm.最后通过制成RTD器件对材料进行验证,器件测试结果表现出良好的直流特性.     

平面型RTD与BJT构成的串联单元特性分析

采用了n+-GaAs衬底和硼离子注入的新型工艺实现了共振隧穿二极管(RTD)的平面化,解决了台面型RTD工艺的不足,得到常温电流峰谷比为2.51∶的平面型RTD(PRTD);利用高级设计系统ADS电路模拟和实验测量对PRTD与BJT串联单元的不同串联方式的电压-电流特性进行了深入分析。这一特性的研究对RTD与异质结双极晶体管(HBT)、MOSFET、高电子迁移率晶体管(HEMT)等三端器件的结合具有普遍意义。     

平面型RTD制作过程中的两个关键工艺

采用n GaAs衬底和自对准B离子注入技术制作了平面型共振隧穿二极管,深入讨论其制作过程中几个关键问题,包括离子注入能量与剂量的选择、RTD负阻区表观正阻现象等,并系统地研究了快速合金工艺温度和时间对于制作良好欧姆接触和消除负阻区表观正阻的影响.结果表明对于所选材料,离子注入能量为130 keV,剂量为4×1013/cm2,退火温度为380℃持续60 s可得到特性较好的PRTD器件,该器件的制作为RTD的应用打下良好基础.     

器件模拟对AIGaAs／GaAs RTD的特性分析

使用SILVACO公司的器件模拟软件ATLAS对A1GaAs／GaAs共振隧穿二极管(RTD)进行了器件模拟，得到了不同结构的RTD的I-V特性曲线。对量子阱宽度、掺杂浓度、势垒宽度和高度对RTD的I-V特性的影响进行了详细的分析。     

MBE生长RTD材料的X射线双晶衍射研究

用分子束外延技术(MBE)生长了GaAs基共振隧穿二极管(RTD)的材料结构,利用X射线双晶衍射(XRD)方法对材料进行了测试分析.结果表明,材料的双晶衍射峰半峰宽达到16.17",GaAs层与In0.1Ga0.9As层的相对晶格失配率仅为0.015 6%.对实验样品进行了双晶衍射回摆曲线的模拟,模拟结果与测试结果符合较好,说明生长的RTD材料结构与设计相符合.通过制成器件对材料进行验证,室温下对器件进行直流测试,PVCR达到5.1,峰值电流密度达到73.6 kA/cm2.     

一种新材料结构的RTD器件的设计及实现

设计了一种带有Al0.22Ga0.78As/In0.15Ga0.85As/GaAs发射极空间层和GaAs/In0.15Ga0.85As/GaAs量子阱的共振隧穿二极管(RTD)材料结构,并且成功地制作了相应的RTD器件.在室温下,测试了RTD器件的直流特性,计算了RTD器件的峰谷电流比和可资电流密度.在分析器件特性的基础上,指出调整材料结构和优化工艺参数将进一步提高RTD器件的性能.     

器件模拟对AlGaAs/GaAs RTD的特性分析(英文)

使用SILVACO公司的器件模拟软件ATLAS对AlGaAs/GaAs共振隧穿二极管(RTD)进行了器件模拟,得到了不同结构的RTD的I-V特性曲线。对量子阱宽度、掺杂浓度、势垒宽度和高度对RTD的I-V特性的影响进行了详细的分析。     

基于共振隧穿理论的GaAs基RTD的设计与研制

以共振能级的透射系数半峰宽(FWHM)做为共振隧穿二极管(RTD)材料结构设计的依据,对GaAs/AlAs/In0.1Ga0.9As材料体系的RTD进行了设计.用分子束外延(MBE)进行了RTD结构材料制备,X射线双晶衍射(XRD)分析表明,制备的异质结界面光滑、层厚准确.RTD采用台面结构,器件特性测试结果表明,峰值...     

GaAs MESFET平面型变容管高频特性分析

本文分析了用于GaAs MMIC调频器件MESFET平面型变容管的微波特性,讨论了器件几何结构与直流参数、S参数之间的关系.重点研究了器件串联电阻对微波特性的影响,给出了变容管变电容比与器件几何尺寸.     

Realization of an n-channel GaAs/AlGaAs bistable transistor(BISFET)

The first realization of a novel heterostructure device, the bistable field-effect transistor (BISFET), is reported. The device uses an n-channel GaAs/AlGaAs inversion channel structure. It contains a positive feedback loop between the gate and source terminals, which is activated above a gate voltage of 1.7 V. This leads to abrupt transitions between high- and low-current states as the drain voltage is changed, with a switching ratio of 1.5. The transitions are accompanied by sharp changes in gate current as the feedback loop turns on and off. These transitions, referred to as switch up and switch down, form a large hysteresis loop in the drain characteristics. Hysteresis as large as 3.7 V is observed, making the device strongly bistable     

Limitations of the back-to-back barrier-intrinsic-n+(BIN) diode frequency tripler

Problems of the back-to-back GaAs barrier-intrinsic-n⁺ (BIN) diode frequency tripler concept along with the associated device physics are presented. The back-to-back GaAs BIN diode structure was originally proposed to have an intrinsic cutoff frequency close to 1 THz and to be a highly efficient millimeter-wave frequency tripler. Frequency limitations will be discussed to explain the failure of the back-to-back GaAs BIN diode as a millimeter-wavelength device. Optimization is also carried out to explore the possibility of improving the high-frequency performance by modifying the BIN diode structure     

RTD/HEMT单片集成中RTD直流参数与材料结构的关系

为了研究器件参数与材料结构的关系,设计了三种不同的GaAs基RTD材料结构。通过完全相同的器件制造工艺,研制出三种RTD器件,并测量了它们的9个直流参数。对测量结果进行了对比和分析。最后针对RTD与HEMT集成时,如何处理RTD与HEMT间的电流匹配问题提出了建议。     

An InGaP/GaAs Merged HBT-FET (BiFET) Technology and Applications to the Design of Handset Power Amplifiers

The last decade has seen GaAs HBTs emerge as the dominant technology in wireless handset power amplifiers. Modern application requirements and size limitations have driven industry leaders towards the co-integration of depletion mode n-FET and GaAs HBT. The merger of Bipolar and FET, or BiFET, gives an additional degree of freedom in the design of advanced power amplifiers independent of a silicon controller. This paper provides an overview of the various techniques that can be used to join the two device technologies and then shows how a merged epitaxial structure, where an FET is formed in the emitter layers of an HBT, combines functional versatility with the high volume manufacturability needed to supply millions of power amplifiers at low cost. A large-signal model of the FET structure is developed which takes into account the unique physics and geometries of the device, including voltage-dependant parameters and charges on all four electrical terminals. Specific handset applications that can benefit or be enabled by BiFET are presented, such as on-off switching, low voltage bias controllers , Auto-Bias power amplifiers, and bias circuits with low or no voltage reference. When npn-only bias circuitry is limited to low voltage reference levels, HBT power amplifiers with BiFET bias stages are shown to have superior RF performance to their npn-only counterparts.     

共振隧穿二极管的设计和研制

用分子束外延在半绝缘砷化镓上生长两垒一阱结构,制成RTD单管。经过材料生长设计、工艺设计和版图设计几方面的改进,测得最高振荡频率已达54GHz。     

RTD/HEMT多值逻辑(MVL)电路的PSPICE模拟

由共振隧穿二极管(RTD)与高电子迁移率晶体管(HEMT)相并联组成的结构是构成当前RTD高速数字电路常用的基本单元。由于RTD的负阻、双稳和自锁特性,由RTD/HEMT组成的逻辑电路可以大大减少器件的数目,用最少的器件完成一定的逻辑功能。本文对多值逻辑(MVL)中的文字逻辑门用PSPICE模拟软件进行了电路模拟,模拟结果与预期结果一致,并有助于指导该电路的设计。     

AlGaAs/GaAs quantum well infrared photodetector focal plane array based on MOCVD technology

128 × 128, 128 × 160 and 256 × 256 AlGaAs/ GaAs quantum well infrared photodetector (QWIP) focal plane arrays (FPA) as well as a large area test device are designed and fabricated. The device with n-doped back-illuminated AIGaAs/GaAs quantum structure is achieved by metal organic chemical vapor deposition (MOCVD) epitaxial growth and GaAs integrated circuit processing technology. The test device is valued by its dark current performance and Fourier transform infrared spectroscopy (FTIR) spectra at 77 K. Cut off wavelengths of 9 and 10.9 μm are realized by using different epitaxial structures. The blackbody detectivity DB* is as high as 2.6 × 109 cm· Hz1/2·W-1. The 128 × 128 FPA is flip-chip bonded on a CMOS readout integrated circuit with indium (In) bumps. The infrared thermal images of some targets under room temperature background have been successfully demonstrated at 80 K operating temperature. In addition, the methods to further improve the image quality are discussed.