CAJ | 학술논문

AlGaN/GaN HEMT良好的功率特性虽然被大量报导,但其电流崩塌现象仍是一个令人困扰的问题,作者通过实验证明了导致其电流崩塌的一个因素.两个AlGaN/GaN样片被分别放在纯氮气和掺碳的氮气气氛中快速退火,利用XPS证明了后者中的碳元素含量远远大于前者.比较二者的I-V特性曲线,可发现碳杂质的引入可使AlGaN/GaN HEMT电流崩塌程度大大增加.分析表明:由碳杂质引入导致的深能级使得负栅压下俘获沟道中的载流子在正栅压下不能立刻释放,从而引起AlGaN/GaN HEMT中的电流崩塌现象.
AlGaN/GaN HEMT량호적공솔특성수연피대량보도,단기전류붕탑현상잉시일개령인곤우적문제,작자통과실험증명료도치기전류붕탑적일개인소.량개AlGaN/GaN양편피분별방재순담기화참탄적담기기분중쾌속퇴화,이용XPS증명료후자중적탄원소함량원원대우전자.비교이자적I-V특성곡선,가발현탄잡질적인입가사AlGaN/GaN HEMT전류붕탑정도대대증가.분석표명:유탄잡질인입도치적심능급사득부책압하부획구도중적재류자재정책압하불능립각석방,종이인기AlGaN/GaN HEMT중적전류붕탑현상.
Although outstanding microwave power performance of AlGaN/GaN HEMTs has been reported,drain current collapse is still a problem. In this paper, an experiment was carried out to demonstrate one factor causing the collapse. Two AlGaN/GaN samples were annealed under N2-atmosphere with and without carbon incorporation, and the XPS measure-ment technique was used to determine that the concentration of carbon impurity in the latter sample was far higher than in the former. From the comparison of two Id-Vds characteristics, we conclude that carbon impurity incorporation is respon-sible for the severe current collapse. The carbon impurity-induced deep traps under negative gate bias stress can capture the channel carriers, which release slowly from these traps under positive bias stress, thus causing the current collapse.