It is herein proposed to grow SiC epitaxial layers via hot-wall chemical vapor deposition (CVD) using a rotation system to greatly improve thickness and doping uniformities. This will improve device performance and yield for all application areas. The advantage of highly uniform epitaxial SiC will be greatest for microwave MESFETs and high power devices. Epitaxy for these two types of devices will be the focus of this program. Recent attempts to improve uniformity in hot wall systems without rotation and cold wall systems with rotation have been encouraging. However, those results still fall short of what is required for device production. At the end of Phase I, we were able to produce SiC epitaxial layer thicknesses up to 20 um with variation of <5% in thickness and <20% in doping. An additional benefit is the ability to deposit on three wafers per reactor run. At the end of Phase II, we should be able to produce layers with variation of <1% in thickness and <7% in doping with a capacity of six 50 mm or three 75 mm wafers per deposition cycle. Evaluation wafers of both Schottky diodes and MESFET device sheet resistance will be mapped to verify the uniformity achieved.
Keywords: 1. uniform 2. epitaxial layers 3. chemical vapor deposition 4. silicon carbide 5. hot wall
