采用复合帽层改善GaAs HEMT/PHEMT的欧姆接触特性  

Improvement of Ohmic Contact Characteristics on GaAs HEMT/PHEMT by Composite Cap Layer Design

作　　者：黄念宁[1] 韩克锋[1] 高喜庆[1] 邹鹏辉[1] 高建峰[1] 

机构地区：[1]南京电子器件研究所,南京210016

出　　处：《固体电子学研究与进展》2015年第2期197-201,共5页Research & Progress of SSE

摘　　要：GaAs HEMT/PHEMT的欧姆特性对器件的性能和可靠性至关重要,通常为了得到最好的欧姆接触特性,帽层(CAP层)的掺杂浓度大约在5E+18cm-3的水平,已经达到了GaAs掺杂的极限。为了进一步改善GaAs HEMT/PHEMT欧姆特性,本文的研究工作是在砷化镓帽层上生长一层10nm厚、具有更小禁带宽度的InGaAs薄层,基于这种新的外延结构,在欧姆制作工艺不变的情况下,制作的欧姆接触具有更低的欧姆接触电阻率和更好的一致性。Ohmic contact is a critical characteristic for performance and reliability of a GaAs HEMT/PHEMT.It has already reached its limitation when the doping density is 5E＋18cm-3in cap layer.To improve the GaAs HEMT/PHEMT ohmic contact characteristics,an additional layer of InGaAs which had a smaller band gap was grown on the top of the cap layer while keeping the ohmic contact formation process unchanged.A lower ohmic contact resistance and better consistency were achieved based on the proposed new epitaxial structure.

关 键 词：复合帽层 接触电阻率 一致性 热可靠性 

分 类 号：TN385[电子电信—物理电子学] TN303