Fundamentals of Silicon Carbide Technology

Chapter 5Characterization Techniques and Defects in Silicon Carbide

Characterization of the physical properties, doping densities, and defects in SiC epitaxial layers and substrates is a fundamental step in the development of SiC devices. Accurate determination of the physical properties and identification of defect structures as well as their behavior are important subjects of academic study. For example, many of the physical properties of SiC that should be used in device simulations are still unknown. It is essential to fully understand the nature of the various defects that are present in SiC, because any of these defects could affect device performance and reliability. In this chapter, the fundamentals of important material characterization techniques are described, and an overview of extended and point defects in SiC is given.

5.1 Characterization Techniques

Almost all the material characterization techniques commonly used are applicable to SiC although special care is often required. The major points that are unique to SiC characterization are summarized as follows:

1. Sample structures (underlying substrate): Characterization of properties or defects in SiC epitaxial layers is often intended because they are likely to be directly linked to the device performance. However, SiC epitaxial layers are often relatively thin , and the influence of the underlying substrates therefore ...