An L-Shaped Trench SOI-LDMOS With Vertical and Lateral Dielectric Field Enhancement

Author

Wang, Zhigang ; Zhang, Bo ; Fu, Qiang ; Xie, Gang ; Li, Zhaoji

Author_Institution

State Key Lab. of Electron. Thin Films & Integrated Devices, Univ. of Electron. Sci. & Technol. of China, Chengdu, China

Volume

33

Issue

5

fYear

2012

fDate

5/1/2012 12:00:00 AM

Firstpage

703

Lastpage

705

Abstract

For the first time, we report a novel L-shaped trench LDMOS on silicon-on-insulator with double (lateral and vertical) enhanced dielectric field (ENDIF) (DENDIF) effect. This device features an L-shaped trench for accumulating charges (mainly, ionized charges) to enhance lateral breakdown voltage (BV). Then, the vertical ENDIF can be self-adaptive to the lateral ENDIF due to the lumped charges (mainly, inversion charges) at the interface of the buried oxide/silicon. The L-shaped trench makes the potential contours as tree roots, which can spread into the folded drift region to prevent premature breakdown in silicon. The simulated results of the DENDIF LDMOS show that the electric field in the dielectric layer is >; 200 V/μm, the gate-drain charge density (Q_gd) is 0.39 nC/mm², and the Baliga´s figure of merit [(FOM); FOM = BV²/R_ON,sp] is 11.9 MW/cm².

Keywords

MOSFET; dielectric materials; electric breakdown; silicon-on-insulator; DENDIF LDMOS; L-shaped trench SOI-LDMOS; Si; accumulating charges; buried oxide/silicon; dielectric layer; gate-drain charge density; ionized charges; lateral breakdown voltage; lateral dielectric field enhancement; silicon-on-insulator; vertical dielectric field enhancement; Dielectrics; Electric breakdown; Electron devices; Logic gates; Silicon; Silicon on insulator technology; Space charge; Breakdown voltage (BV); dielectric field enhancement; enhanced dielectric field (ENDIF); silicon-on-insulator (SOI); trench LDMOS;

fLanguage

English

Journal_Title

Electron Device Letters, IEEE

Publisher

ieee

ISSN

0741-3106

Type

jour

DOI

10.1109/LED.2012.2188091

Filename

6172645