Minority Carrier Trap in n-Type 4H–SiC Schottky Barrier Diodes

Ivana Capan,Yuichi Yamazaki,Takeshi Ohshima,Takahiro Makino,Yuya Oki,Tomislav Brodar

doi:10.3390/cryst9070328

Abstract

We present preliminary results on minority carrier traps in as-grown n-type 4H–SiC Schottky barrier diodes. The minority carrier traps are crucial for charge trapping and recombination processes. In this study, minority carrier traps were investigated by means of minority carrier transient spectroscopy (MCTS) and high-resolution Laplace-MCTS measurements. A single minority carrier trap with its energy level position at Ev + 0.28 eV was detected and assigned to boron-related defects.

Highlights

Owing to its many advantages over silicon, silicon carbide (SiC), in its 4H polytype, is becoming a mainstream material for the industry of high-power electronics
SiC diodes for radiation detection are highly sensitive to defects that introduce deep levels which act as recombination centers and degrade carrier lifetimes
The main recombination center in n-type 4H–SiC is known as Z1/2 and it has been identified as a (=/0) transition from the single carbon vacancy (VC ) [1]

Summary

Introduction

Owing to its many advantages over silicon, silicon carbide (SiC), in its 4H polytype, is becoming a mainstream material for the industry of high-power electronics. Minority carriers in Schottky barrier diodes (SBDs) could be optically generated by use of above-bandgap light [6]. The first experimental application of the generation of minority carriers by use of a light with an energy just above the bandgap energy as a technique for manipulating the occupancy of deep states was described by Hamilton et al [7] and it was called the minority carrier capture (MCC) method It was further developed into minority carrier transient spectroscopy (MCTS). Majority carrier traps were analyzed by means of conventional DLTS and minority carrier traps were measured by MCTS and Laplace-MCTS Figure 1 shows schematic representation of the experimental setup (Figure 1a) and the semi-transparent n-type 4H–SiC Schottky barrier diode

Result and Discussion

Schematic representation of the experimental setup and semi-transparent

Conclusions