Development of SiC Super-Junction (SJ) Devices by Multi-Epitaxial Growth

Abstract

Super-junction (SJ) devices have been developed to improve the trade-off relationship between the blocking voltage (VBD) and specific on-resistance in unipolar power devices. This SJ structure effect is expected in SiC unipolar devices. Multi-epitaxial growth is a known fabrication method for SJ structures where epitaxial growth and ion implantation are repeated alternately until a certain drift-layer thickness is achieved. In this study, we fabricated two types of test elemental groups with an SJ structure to evaluate the breakdown voltage (VBD) and specific resistivity of the drift layer (Rdrift). Experimental results show that VBDexceeded the theoretical limit of the 4H-SiC by 300V, and Rdriftagreed well with the estimated value from the device simulation. The beneficial effects of the SJ structure in the SiC material on VBDand Rdriftwere confirmed for the first time.