A power device material of corundum-structured α-Ga 2 O 3 fabricated by MIST EPITAXY ® technique

Corundum-structured oxides have been attracting much attention as next-generation power device materials. A corundum-structured α-Ga 2 O 3 successfully demonstrated power device operations of Schottky barrier diodes (SBDs) with the lowest on-resistance of 0.1 mΩ cm 2 . The SBDs as a mounting device of TO220 also showed low switching-loss properties with a capacitance of 130 pF. Moreover, the thermal resistance was 13.9 °C/W, which is comparable to that of the SiC TO220 device (12.5 °C/W). On the other hand, corundum-structured α-(Rh,Ga) 2 O 3 showed p-type conductivity, which was confirmed by Hall effect measurements. The Hall coefficient, carrier density, and mobility were 8.22 cm 3 /C, 7.6 × 10 17 /cm 3 , and 1.0 cm 2 V −1 s −1 , respectively. These values were acceptable for the p-type layer of pn diodes based on α-Ga 2 O 3 .