Phosphorous from P2O5 is more effective than nitrogen for passivating the 4H-SiC SiO2 interface. The peak value of the field-effect mobility for 4H-SiC metal-oxide-semiconductor field-effect transistors (MOSFETs) after phosphorus passivation is approximately 80 cm 2 V̇s. However, P2O5 converts the SiO 2 layer to phosphosilicate glass (PSG)-a polar material that introduces voltage instabilities which negate the benefits of lower interface trap density and higher mobility. We report a significant improvement in voltage stability with mobilities as high as 72 cm2V̇s for MOSFETs fabricated with a thin PSG gate layer (∼10 nm) capped with a deposited oxide.
- silicon carbide
- thin phosphosilicate glass (PSG)
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Electrical and Electronic Engineering