High frequency doubling efficiency THz GaAs Schottky barrier diode based on inverted trapezoidal epitaxial cross-section structure

A high-performance terahertz Schottky barrier diode (SBD) with an inverted trapezoidal epitaxial cross-sectional structure featuring high varactor characteristics and reverse breakdown characteristics is reported in this paper. Inductively coupled plasma dry etching and dissolution wet etching are used to define the profile of the epitaxial layer, by which the voltage-dependent variation trend of the thickness of the metal-semiconductor contact depletion layer is modified. The simulation of the inverted trapezoidal epitaxial cross-section SBD is also conducted to explain the physical mechanism of the electric field and space charge region area. Compared with the normal structure, the grading coefficient M increases from 0.47 to 0.52, and the capacitance modulation ratio (C_max/C_min) increases from 6.70 to 7.61. The inverted trapezoidal epitaxial cross-section structure is a promising approach to improve the variable-capacity ratio by eliminating the accumulation of charge at the Schottky electrode edge. A 190 GHz frequency doubler based on the inverted trapezoidal epitaxial cross-section SBD also shows a doubling efficiency of 35% compared to that 30% of a normal SBD.     

基于ATE的SerDes功能测试技术研究

随着半导体行业的发展，特别是传输接口的发展，人们对传输速度的要求越来越高，串化器/解串器（SerDes）技术正在取代传统的并行传输成为新型的高速串口接口的主流。SerDes高速串行接口电路接口复杂，性能要求严格，为保证电路正常生产测试，对SerDes电路功能测试技术研究非常必要。基于ATE测试机台，重点针对SerDes类型电路的功能测试方法进行了研究。     

基于完全互补码扩频的通信雷达一体化系统

海量的设备接入网络极易导致严重的频谱拥堵,通信雷达一体化是应对该挑战的关键方法之一。然而,如何有效应对多用户和多目标之间的自干扰和互干扰是通信雷达一体化亟待解决的基础难题。为此,借助码分复用机理,将完全互补码作为扩频码,设计通感一体化信号,构建了多用户和多目标场景下的通信雷达一体化方案。仿真结果表明,与典型的扩频方案相比,所提方案具有更低的误码率与更高的频谱效率;此外,当信噪比较低时,所提方案可以对更多目标进行探测。