Magnetoresistance characterisation of 4H-SiC MOSFETs

Geometrical magnetoresistance measurements on 4H-SiC metal-oxide-semiconductor field-effect transistors (MOSFET) were performed under high magnetic field conditions (12T). Three n-channel samples were investigated with p-well acceptor concentrations of 5×10¹⁵ cm^-3, 2×10¹⁷cm^-3 and 2×10¹⁷cm^-3. The results indicate relatively high carrier mobilities. However, the devices were found to be affected by a nearly quadratic dependence of the sheet electron density on gate bias. This behaviour is attributable to charge trapping in the channel.