A novel SiGe/Si hetero-junction power diode utilizing an ideal ohmic contact

Abstract

Novel structure to realize an ideal ohmic contact with the n/sup +/ region substituted by p/sup +/-n/sup +/ mosaic structure for the p/sup +/(SiGe)-n/sup -/-n/sup +/ hetero-junction switching power diodes is proposed. The reverse recovery characteristics of p/sup +/(SiGe)-n/sup -/-n/sup +/ diodes utilizing an ideal ohmic contact are much more improved but not notably sacrificing the forward voltage drop. there are about two thirds shorter in the reverse recovery time and a half shorter in peak reverse current than conventional p/sup +/(SiGe)-n/sup -/-n/sup +/ diodes, furthermore, far lower leakage current is exhibited. The new kind of high-speed and soft p/sup +/(SiGe)-n/sup -/-n/sup +/ diode is easily incorporated into monolithic combination with transistors, and is useful for various power applications. These improvements are achieved without resorting lifetime killing and thus the devices can be easily integrated into power ICs.