GaN HFET沟道中的强场峰和背势垒

Peaked Electric Field in Channel and Back Barrier in GaN HFET

研究了背势垒、场板电极、电流崩塌、短沟道效应及源-漏穿通等GaN HFET的热点课题及其关联。高漏压下沟道阱中的强场峰和背势垒的相互作用是决定上述热点课题的关键。介绍、分析了目前国外用Silvaco有限元经典模拟软件计算的结果,发现这些理论计算的能带都向缓冲层末端倾斜,电子从沟道阱转移到缓冲层末端,不能用来研究上述课题和进行器件优化设计。提出了新的量子模拟理念,用沟道阱的量子限制解开了上述难题。量子模拟结果解释了上述课题的实验结果及其关联,有望从沟道强场峰和背势垒的相互作用研究中优化设计出高漏压工作的大功率、高效GaN HFET。

The back barrier, field plate electrode, current collapse, short channel effect, source-drain punch through and other hot problems and their correlations are investigated in this paper. The interaction between the strong peaked electric field in channel and the back barrier under high drain voltage determines the mentioned above issues. The published energy bands of heterostructure quantum well under high drain voltage calculated by classical software such as Silvaco are introduced and analyzed. It is found that these calculated energy bands all incline from the channel quantum well to the end of buffer, to where the electrons in channel well are trans- ferred. It is impossible to investigate the mentioned above issues and implement the optimization of GaN HFET design by using these classical software. A new quantum model is proposed in this paper to resolve the difficulty in above classical software by the quantum confinement in the chan- nel well. The above problems and their correlation have been explained by the calculated energy bands. It is hoped that some excellent GaN HFETs with high power and high PAE under high drain voltage can be optimally designed from the investigation of interaction between the strong peaked electric field in channel and the back barrier under high drain voltage.