A TCAD Study on High-Voltage Superjunction LDMOS with Variable-K Dielectric Trench

Micromachines

Hongwei Zhang¹  Qi Sun¹  Chuanfeng Ma¹  Licheng Jiao¹  Qian Wang¹  Zhen Cao¹ 

[1] School of Artificial Intelligence, Xidian University, Xi’an 710071, China;

关键词: superjunction;    LDMOS;    electric field modulation;    dielectric RESURF;    breakdown voltage;   

DOI  :  10.3390/mi13060843

来源: DOAJ

【 摘 要 】

In this paper, a novel high voltage superjunction lateral double diffused MOSFETs (SJ-LDMOS) using a variable high permittivity (VHK) dielectric trench is presented. A relatively high HK dielectric is in the upper trench, which is connected with the drain electrode to suppress the high electric field (E-field) peak under the drain by the dielectric reduced surface field (RESURF) effect. In addition, a relatively low HK dielectric is at the bottom of the trench. On the one hand, the substrate is effectively depleted by a suitable HK dielectric layer, and the vertical depletion region of the substrate is greatly expanded. On the other hand, the overall vertical bulk E-field distribution is modulated by the E-field peaks generated at the position of varying K dielectric. A more uniform bulk E-field distribution is obtained for VHK SJ-LDMOS, leading to a high breakdown voltage (BV). Compared to the conventional SJ-LDMOS, the blocking voltage per micron of the drift region of VHK SJ-LDMOS has increased by 41.2%. Besides, compared with the SJ-LDMOS with a uniform-K, the BV of VHK SJ-LDMOS is improved by about 9.5%. The condition of the optimal range of the variable high permittivity is also presented. Meanwhile, the proposed VHK SJ-LDMOS has good conduction characteristics and heat dissipation

【 授权许可】

Unknown