Improved Interface Trap Density Close to the Conduction Band Edge of a-Face 4H-SiC MOSFETs Revealed Using the Charge Pumping Technique
We study the interface properties of 4H silicon carbide Si-face 0001 and a-face 11220 power MOSFETs using the charge pumping technique. MOSFETs produced on the a-face show a higher electron mobility than Si-face devices, although their charge pumping signal is 5 times higher, indicating a higher interface/border trap density. We show the main contribution to the interface/border trap density on a-face devices originates from deep states in a wide range around midgap, whereas Si-face devices show a higher and exponentially increasing interface/border state density close to the conduction band edge of 4H silicon carbide, resulting in reduced mobility.
Konstantinos Zekentes, Konstantin V. Vasilevskiy and Nikolaos Frangis
G. Rescher et al., "Improved Interface Trap Density Close to the Conduction Band Edge of a-Face 4H-SiC MOSFETs Revealed Using the Charge Pumping Technique", Materials Science Forum, Vol. 897, pp. 143-146, 2017