gaas mosfet射频开关器件与电路的研究-research on gaas mosfet rf switching devices and circuits.docx

摘要随着当今通讯科技的飞速发展，以移动通信、雷达、卫星通信等为代表的无 线通信系统对射频开关的开关速度、功率容量、开关损耗等各方面性能均提出了 不断提高的新要求。在常用的射频开关器件中，固态 FET 射频开关以其出色的性 能和极高的集成度广泛应用于移动无线通信中，其中又以 Si 基 SOI 器件和 GaAs 基 HEMT 器件应用最为普遍。本文以为 GaAs MOSFET 核心内容，开展了以下方 面的研究：1. 本文介绍了 GaAs 器件的基础知识，对 GaAs MOSFET 结构与常见 HEMT 结构进行了比较。同时对 GaAs MOS 结构的沉积前退火（PDA）进行了研究，在 550℃氧气氛围退火条件下得到一个相对最优的介质层厚度，并讨论了影响 GaAs MOS 退火特性的因素。进一步探究了生长中采用臭氧处理对 InP/Al2O3 界面的影响。2. 本文介绍了射频开关的基础知识，同时基于中国科学院微电子研究所的GaAs MOSFET 工艺，制作了适合开关应用的栅长 0.5μm InGaP/InGaAs MOSFET 射频开关器件，并对其进行了直流特性以及开关特性的测试和表征。根据测试结 果进行了小信号建模，并利用该模型设计了一款单刀四掷的射频开关电路。关键词：InGaP/InGaAs MOSFET 射频开关 PDAAbstractWith the development of communication techniques, higher performance of on/off speed, power handling and insertion loss is required for radio-frequency (RF) switches in the application of mobile communications, radar and satellite communications. Among common RF switch devices, solid field effect transistor (FET) stands out for its excellent performance and high integrated level, while Si based silicon-on-insulator (SOI) devices and GaAs based high mobility electronic transistor (HEMT) devices are most widely used in solid FETs. Centering in GaAs MOSFET, researches shown below are conducted in this thesis.Basis of GaAs devices was introduced. Comparison of GaAs MOSFET and GaAs HEMT was done in this paper. Research was also done in the condition for post deposition annealing (PDA) in oxygen ambient for GaAs MOS structure, and a relatively optimum thickness of dielectric layer was given together with the discussion of the factors affecting GaAs MOS annealing property.Fundamentals of RF switches were introduced. An InGaP/InGaAs MOSFET applying on RF switches was fabricated based on the InGaP/InGaAs MOSFETs fabrication process with its gate length of 0.5μm. DC and S parameter measurement was done to show its RF switch characters. According to the result of measurements, a SP4T switch was designed.Keywords: InGaP/InGaAs MOSFETRF switchPDA目录摘要...............................................................