Prototyping a SiC JFET Drop-in Replacement Module for a 600-V, 600-A Si IGBT Half-Bridge Module

摘要

Silicon carbide power vertical-channel junction field effect transistors (VJFETs) are ideal candidates for next generation vehicle power systems. They combine the switching speed of MOSFETs with the voltage and current handling properties of IGBTs and the excellent thermal properties derived from the SiC material. As a unipolar device they can be easily paralleled over the entire operating range of the device and generate extremely high current for high power application. With the drop-in replacement, the case temperature of the motor drive can be significantly increased above the current limit of 80 ℃, which will permit the designer new opportunities for decreasing size, weight, and cost.rnWith current die area yields, the only way to fabricate high-current IPMs that can address 600-A IGBT replacement is to parallel SiC die. A process for packaging a 600-V, 600-A IGBT replacement module based on very low specific on-resistance SiC VJFETs (2.5 mΩcm~2 ) co-packed with SiC Schottky Barrier Diodes (SBD) is reported. The design covering thermal design, material selection, and thermal (soldering) budget for the DBC and copper base plate commercial packaging is presented. The DBC design will be presented, which took into consideration accommodating 80 VJFETs in parallel and 40 SBDs in anti-parallel. All DBC were screened for single die failures using a multi-step process including high-temperature reverse bias screening. Finite element thermal analysis was utilized for appropriate packaging material selection. Successful completion of the packaging process was confirmed by DC and switching characterization.