Concept and design of super junction devices

Abstract

The super junction (SJ) has been recognized as the " milestone” of the power MOSFET, which is the most important innovation concept of the voltage-sustaining layer (VSL). The basic structure of the SJ is a typical junction-type VSL (J-VSL) with the periodic N and P regions. However, the conventional VSL is a typical resistance-type VSL (R-VSL) with only an N or P region. It is a qualitative change of the VSL from the R-VSL to the J-VSL, introducing the bulk depletion to increase the doping concentration and optimize the bulk electric field of the SJ. This paper firstly summarizes the development of the SJ, and then the optimization theory of the SJ is discussed for both the vertical and the lateral devices, including the non-full depletion mode, the minimum specific on-resistance optimization method and the equivalent substrate model. The SJ concept breaks the conventional " silicon limit” relationship of Ron∝VB2.5, showing a quasi-linear relationship of Ron∝VB1.03.

Performance and Reliability Review of 650 V and 900 V Silicon and SiC Devices: MOSFETs, Cascode JFETs and IGBTs

“…This application space has historically been dominated by silicon IGBTs; however, this is changing. MOSFETs are applicable in automotive medium voltage applications only if the conduction losses are minimized by wide bandgap (WBG) materials (like SiC [5] and GaN [6]) or if innovative device design techniques like charge balance from super-junction layouts are used in silicon [7]. Hence a plethora of 650 V to 1.2 kV SiC power MOSFETs have been commercialized alongside 600 V to 900 V super-junction silicon MOSFETs and 650 V enhancement mode GaN FETs.…”

Evaluation of silicon carbide Schottky barrier diode within guard ring by multifunctional scanning probe microscopy

“…[3][4][5][6][7][8][9][10][11][12] However, the performance improvement of silicon (Si) power devices has approached the limit. 13,14) It is difficult to achieve lower on-resistance and higher breakdown voltages using Si power devices. Therefore, wide band gap semiconductor (WGS) materials are expected to improve the performance.…”