Observation of single-carrier space-charge-limited flow in nitrogen-doped α-silicon carbide. I. I-V characteristics and impedance

Abstract

This paper first reviews the properties of silicon carbide, in which polytypism is a salient feature. If a highly compensated insulating polytype is sandwiched between low resistive polytypes, space‐charge injection will occur. The theory of space‐charge‐limited current flow in the presence of traps is reviewed and a somewhat different version of the standard theory is presented, which shows more clearly the ohmic and space‐charge‐limiting regimes. Close analytical parametric forms for I and V are obtained. Experimental data on I‐V characteristics and impedance are presented for 52–300 K. Except at the highest temperature, four regimes are clearly visible in the I‐V curves. A quantitative comparison with the theory is made and various transport quantities for α‐SiC are deduced.