%0 Journal Article
%T Characterization of Al2O3/GaN/AlGaN/GaN metal–insulator–semiconductor high electron mobility transistors with different gate recess depths
%A 马晓华
%A 潘才渊
%A 杨丽媛
%A 于惠游
%A 杨凌
%A 全思
%A 王昊
%A 张进成
%A 郝跃
%J 中国物理 B
%D 2011
%I 
%X In this paper, in order to solve the interface-trap issue and enhance the transconductance induced by high-k dielectric in metal--insulator--semiconductor (MIS) high electron mobility transistors (HEMTs), we demonstrate better performances of recessed-gate Al2O3 MIS-HEMTs which are fabricated by Fluorine-based Si3N4 etching and chlorine-based AlGaN etching with three etching times (15 s, 17 s and 19 s). The gate leakage current of MIS-HEMT is about three orders of magnitude lower than that of AlGaN/GaN HEMT. Through the recessed-gate etching, the transconductance increases effectively. When the recessed-gate depth is 1.02 nm, the best interface performance with tauit=(0.20--1.59) μs and Dit=(0.55--1.08)×1012 cm-2·eV-1 can be obtained. After chlorine-based etching, the interface trap density reduces considerably without generating any new type of trap. The accumulated chlorine ions and the N vacancies in the AlGaN surface caused by the plasma etching can degrade the breakdown and the high frequency performances of devices. By comparing the characteristics of recessed-gate MIS-HEMTs with different etching times, it is found that a low power chlorine-based plasma etching for a short time (15 s in this paper) can enhance the performances of MIS-HEMTs effectively.
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=47EA7CFDDEBB28E0&jid=CD8D6A6897B9334F09D8D1648C376FB4&aid=E2F6F31D08708807DEF67B512C3C383E&yid=9377ED8094509821&vid=A04140E723CB732E&iid=0B39A22176CE99FB&journal_id=1009-1963&journal_name=中国物理&referenced_num=0&reference_num=23