Defects and Impurities in 4H- and 6H-SiC Homoepitaxial Layers: Identification, Origin, Effect on Properties of Ohmic Contacts and Insulating Layers and Reduction

摘要

L.8+-0.4 X10 TO THE 7TH POWER V/cm were determined for chynoweth's equation for 6H-SiC and 4H-SiC, respectively, at room temperature. The coefficient ap was found to decrease with increasing temperature for both polytypes while the coefficient bp remained constant Based upon this data, the breakdown voltage of the 4H and 6H-SiC devices is predicted to increase with temperature which is an important desirable characteristic for power devices. The electrical characteristics of lateral n-channel MOSFETs fabricated on 4H-SiC are reported for the first time. Inversion layer electron mobilities of 165 sq cm/Vs in 4H-SiC MOSFETs were measured at room temperature.