Development of silicon carbide epitaxial wafers with reduced micropipe density

In this project Technologies and Devices International, Inc. (TDI) proposes-to develop silicon carbide (SiC) substrate material with reduced micropipe density. Our recent testing has demonstrated that micr( pipe density in SiC commercial wafers can be significantly reduced by filling micropipe channels in these wafers using a new SiC epitaxial approach After filling the micropipe in the initial wafer, we will grow a SiC homoepitaxial layer on the top of this wafer, forming a SiC epitaxial wafer with reduced micropipe density Such epitaxial wafers can be used as substrates for subsequent device fabrication or as seeds for SiC bulk growth These results afford the opportunity to develop SiC substrate material for large area high-power SiC devices. The goal of the Phase I project is to prove this concept and demonstrate a 41 mm diameter 6H-SiC and 4H-SiC wafers with average micropipe density less than 5 per cm2. We will also investigate how to apply this technology for larger SiC wafers. Test samples will be delivered. In Phase II, we plan to develop a multi-wafer production process for 2-inch (and 3-inch, if commercially available) 6H-SiC and 4H-SiC epitaxial wafers with reduced micropipe density. Phase II research will focus on growth technology for providing SiC epitaxial wafers without micropipes