GaN HFET中的陷阱和局域电子气  

Traps and Localized Electron Gases in GaN HFET

作　　者：薛舫时[1] 

机构地区：[1]南京电子器件研究所,微波毫米波单片集成和模块电路重点实验室,南京210016

出　　处：《固体电子学研究与进展》2015年第3期207-216,共10页Research & Progress of SSE

摘　　要：研究了GaN HFET中陷阱的各种行为,发现许多特性不能简单地用陷阱中心俘获带内电子模型来解释。从内、外沟道陷阱密度的巨大差异推出外沟道高密度陷阱不是由陷阱中心俘获带内电子产生的。通过自洽求解二维泊松方程和薛定谔方程发现栅-漏间隙中的强场峰在其两侧产生巨大能带畸变,使部分二维电子气不能通过强场峰而形成局域电子气。运用这一局域电子气新概念解释了目前实验中观察到的各类陷阱实验,说明目前陷阱研究把高密度局域电子气误认为"陷阱"而引入的各种误解。提出了从局域电子气研究来解决GaN HFET电流崩塌和可靠性难题的新途径。The various behaviors of traps in HFET were compared in this paper,from which it was found that many behaviors couldn′t be interpreted by the tapping of electron in traps from energy band.It was proposed from the large difference of trap density between inner and outer channel that the high density traps in outer channel were not induced by the tapping of electrons in traps.Through self-consistent solving of two dimensional Poisson equation and Schrodinger equation,it was found that a large band deformation was produced between two sides of the strong electric field peak in the gate-drain gap,which made the partial two dimensional electron gases not able to move through the strong electric field peak and some localized electron gases were formed.By using this new concept of localized electron gases,the experimental phenomena of traps in GaN HFET could be interpreted,from which it was proposed that the localized electron gases were mistaken for‘traps' in these trap experiments.A new path to solve the difficult problem for current collapse and reliability in GaN HFET was proposed from the deep investigation of localized electron gases.

关 键 词：氮化镓异质结场效应管的陷阱 外沟道中的能带畸变 局域电子气 陷阱与局域电子气的相互作用 电流崩塌 可 

分 类 号：TN386[电子电信—物理电子学]