In a semiconductor device that uses a silicon carbide semiconductor substrate having p type, n type impurity semiconductor regions formed by ion implantation, the electrical characteristics of the end semiconductor device can be improved by decreasing the roughness of the silicon carbide semiconductor substrate surface. The invention comprises placing an end of the shaft into shaft support apertures in the hub, fitting a thrust bearing counterplate into a recess defined by an annular retaining flange that is proximate the end of the shaft, and deforming the counterplate to form a gap between the end of the shaft and a surface of the counterplate. The invention further relates to genetic complements of plants of variety CH796937. If the version of the embedded KBC is newer than the version of the KBC in the system, a KBC flashing process is performed during a POST of the system. When the supplied operation log is a negative history, a program vector corresponding to the operation log is additionally stored as a negative history, and a negative history vector is generated from a sum of program vectors.