Reduction of Density of 4H-SiC / SiO<sub>2</sub> Interface Traps by Pre-Oxidation Phosphorus Implantation

The effect of phosphorus (P) on the electrical properties of the 4H-SiC / SiO 2 interface was investigated. Phosphorus was introduced by surface-near ion implantation with varying ion energy and dose prior to thermal oxidation. Secondary ion mass spectrometry revealed that only part of the implanted P followed the oxidation front to the interface. A negative flatband shift due to residual P in the oxide was found from C - V measurements. Conductance method measurements revealed a significant reduction of density of interface traps D it with energy E C - E it > 0.3 V for P + -implanted samples with [P] interface = 1.5 10 18 cm -3 in the SiC layer at the interface.