Coeffect of trapping behaviors on the performance of GaN-based devices *Project supported by the National Natural Science Foundation of China (Nos. 61604137, 61674130). (September 2018)

• Record Type: Journal Article
• Authors: Zhou, Xingye; Tan, Xin; Wang, Yuangang; Song, Xubo; Xu, Peng; Gu, Guodong; Lü, Yuanjie; Feng, Zhihong
• Is Part Of: Journal of semiconductors. Volume 39:Number 9(2018:Sep.)
• Publication Date: 2018-09
• Subjects: GaN-based HEMT -- device physics -- trapping effect -- transient simulation; 2520D -- 2560P; Semiconductors -- Periodicals; 621.38152
• DOI: 10.1088/1674-4926/39/9/094007
• Languages: English
• ISSNs: 1674-4926

Abstract

Abstract: Trap-induced current collapse has become one of the critical issues hindering the improvement of GaN-based microwave power devices. It is difficult to study the behavior of each trapping effect separately with the experimental measurement. Transient simulation is a useful technique for analyzing the mechanism of current collapse. In this paper, the coeffect of surface- and bulk-trapping behaviors on the performance of AlGaN/GaN HEMTs is investigated based on the two-dimensional (2D) transient simulation. In addition, the mechanism of trapping effects is analyzed from the aspect of device physics. Two simulation models with different types of traps are used for comparison, and the simulated results reproduced the experimental measured data. It is found that the final steady-state current decreases when both the surface and bulk traps are taken into account in the model. However, contrary to the expectation, the total current collapse is dramatically reduced (e.g. from 18% to 4% for the 90 nm gate-length device). The results suggest that the surface-related current collapse of GaN-based HEMTs may be mitigated in some degree due to the participation of bulk traps with short time constant. The work in this paper will be helpful for further optimization design of material and device structures.