Generation of amorphous SiO/SiC interface structure by the first-principles molecular dynamics simulation

Miyashita, Atsumi; Onuma, Toshiharu*; Iwasawa, Misako*; Tsuchida, Hidekazu*; Yoshikawa, Masahito

SiC semiconductor devices are expected to be used in severe environments. However, SiC devices don't present the theoretically expected performance. This is considered to be attributed to the SiO/SiC interface defects that reduce electrical characteristics of devices. To generate the real device interface structure with the computer simulation, it is important to construct the a-SiO structure on SiC. The slab model using 444 atoms for a-SiO on a 4H-SiC (0001) crystal layer was constructed by using first-principles MD simulation. The heating and rapid quenching method was carried out to make an a-SiO/SiC interface structure. The heating temperature, the heating time and the speed of rapid quenching is 4000 K, 3.0 ps and -1000 K/ps, respectively. The interatomic distance and the bond angles of SiO layers agreed well with the most probable values in bulk a-SiO, and there were no coordination defects in the neighborhood of the SiC substrate.