1. Rzhanov Institute of Semiconductor Physics SB RAS, 13 Lavrentiev Av., Novosibirsk 630090, Russia
2. Department of Semiconductor Devices and Microelectronics, Novosibirsk State Technical University, 20 K. Marx Str., Novosibirsk 630073, Russia
3. Joint Institute for High Temperatures RAS, Izhorskaya Str. 13 Bd.2, Moscow 125412, Russia