Simulations of Deep-Level Transient Spectroscopy for 4H-SiC
1. Introduction
Silicon carbide is expected to be an excellent device material as high voltage and low-loss power devices. Recently, SBD (Schottky Barrier Diode) and MOSFET based on silicon carbide have been realized [1-3], however, those devices have some problems for its reliability and control of the IV characteristics. The problems are related to defects in the bulk and at the interface of insulator/semiconductor. The concentration (~5e12[/cm3]) of the defects is 2 orders higher than that of silicon [4], and so the defects cause degradation of device characteristics. The investigation of the defect property is important for the improvement of the device performance.
The DLTS (Deep Level Transient Spectroscopy) is one of the method used in measuring material properties such as energy levels and electrons and holes capture cross sections. The device simulator: Atlas can specify an energy level and a capture cross section, and then, can simulate the DLTS signal. So, we can calibrate the defect properties to the DLTS measurement data accurately and the derived defect properties can be applied to the simulations of device characteristics.
In this article, we demonstrate device simulations of the DLTS signal for a SBD structure with the Z1/Z2 center trap of carbon-vacancy in the bulk.
