Defect Characterization in Silicon Carbide by Cathodoluminescence
Abstract
During homoepitaxial growth of silicon carbide (SiC), structural defects propagate from the substrate into the growing epitaxial layer. Locating and characterizing these defects are key to assessing the quality of the material and understanding the influence of the defects on device properties. Cathodoluminescence (CL) imaging has been reported to nondestructively locate defects in gallium nitride (GaN) by observing the lower intensity of the band edge CL. Similar to GaN, the structural defects in SiC may work as recombination paths for minority carriers and may exhibit a similar behavior. The literature has not shown use of CL to locate linear defects, such as basal place dislocations, threading edge dislocations, or threading screw dislocations for SiC. It is expected to be more difficult to locate defects in SiC compared to GaN due to the far lower density of defects (~103 vs. ~104106 cm3). This study investigates CL as an alternative method to locate and identify linear, planar, and morphological structural defects in 4H-SiC in a nondestructive manner. This is accomplished through CL mapping followed by a destructive defect etch to confirm the locations of defects. Improvements to the equipment and approach are discussed for follow-up work to this study.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2020
- Accession Number
- AD1089735
Entities
People
- Brenda Vanmil
- Harun G. Ganesan
- Robin Karhu
Organizations
- United States Army Research Laboratory