Patent ID: 9337027
Filing Date: 2016-05-10
CPC Classification: C23C,C30B,H01L

Claim Text:
1. A method for depositing silicon carbide coating onto a single crystal silicon carbide substrate such that the resulting coating has a carrier lifetime of 0.5-1000 microseconds, the method comprising a. continuously introducing a controlled amount of a gas mixture comprising a chlorosilane gas, wherein the chlorosilane gas is dichlorosilane gas, methylhydrogendichlorosilane gas, dimethyldichlorosilane gas, or mixtures thereof, a carbon-containing gas, and hydrogen gas into one portion of a reaction chamber containing a 4H single crystal silicon carbide substrate having an angle of tilt of 4 to 8 degrees while drawing a vacuum from another site in the reaction chamber so as to cause flow of the vapor to be uniform over the area of the substrate; b. heating the substrate to a temperature of greater than 1200° C. but less than 1800° C.; with the proviso that the pressure within the reaction chamber is maintained in the range of 10 to 250 torr, wherein a total gas flow rate is 1-150 liters per minute, and a combined flow rate of the chlorosilane gas and carbon-containing gas is 0.1 to 30% of the total flow rate, wherein the resulting single crystal silicon carbide substrate contains a 4H silicon carbide epitaxial layer having a thickness of 1 nm up to 25 cm.