Please wait a minute...
 Chin. Phys. B, 2022, Vol. 31(9): 098502    DOI: 10.1088/1674-1056/ac6159
 INTERDISCIPLINARY PHYSICS AND RELATED AREAS OF SCIENCE AND TECHNOLOGY Prev   Next

# Improvement on short-circuit ability of SiC super-junction MOSFET with partially widened pillar structure

Xinxin Zuo(左欣欣)1,2, Jiang Lu(陆江)1,†, Xiaoli Tian(田晓丽)1, Yun Bai(白云)1, Guodong Cheng(成国栋)1,2, Hong Chen(陈宏)1, Yidan Tang(汤益丹)1, Chengyue Yang(杨成樾)1, and Xinyu Liu(刘新宇)1,‡
1 Institute of Microelectronics of the Chinese Academy of Sciences, Beijing 100029, China;
2 University of Chinese Academy of Sciences, Beijing 100029, China
Abstract  A novel 1200 V SiC super-junction (SJ) MOSFET with a partially widened pillar structure is proposed and investigated by using the two-dimensional numerical simulation tool. Based on the SiC SJ MOSFET structure, a partially widened P-region is added at the SJ pillar region to improve the short-circuit (SC) ability. After investigating the position and doping concentration of the widened P-region, an optimal structure is determined. From the simulation results, the SC withstand times (SCWTs) of the conventional trench MOSFET (CT-MOSFET), the SJ MOSFET, and the proposed structure at 800 V DC bus voltage are 15 μs, 17 μs, and 24 μs, respectively. The SCWTs of the proposed structure are increased by 60% and 41.2% in comparison with that of the other two structures. The main reason for the proposed structure with an enhanced SC capability is related to the effective suppression of saturation current at the high DC bias conditions by using a modulated P-pillar region. Meanwhile, a good Baliga's FOM ($BV^{2}/R_{\rm on}$) also can be achieved in the proposed structure due to the advantage of the SJ structure. In addition, the fabrication technology of the proposed structure is compatible with the standard epitaxy growth method used in the SJ MOSFET. As a result, the SJ structure with this feasible optimization skill presents an effect on improving the SC reliability of the SiC SJ MOSFET without the degeneration of the Baliga's FOM.
Keywords:  silicon carbide (SiC)      short-circuit (SC)      super-junction (SJ)      trench MOSFET
Received:  24 December 2021      Revised:  10 March 2022      Accepted manuscript online:  28 March 2022
 PACS: 85.30.-z (Semiconductor devices) 85.30.De (Semiconductor-device characterization, design, and modeling)
Fund: Project supported by the Key Research and Development Program of Guangdong Province, China (Grant No. 2019B090917010).
Corresponding Authors:  Jiang Lu, Xinyu Liu     E-mail:  lujiang@ime.ac.cn;xyliu@ime.ac.cn