Development of 4H-SiC MOSFETs with Phosphorus-Doped Gate Oxide

In this article, we show some new results regarding the electrical properties of 4H-SiC MOSFETs fabricated by thermal annealing using POCl3. The temperature dependence of MOSFET properties is described and the effect of POCl3 annealing followed by forming gas annealing is shown. POCl3-annealed MOSFETs indicates negative temperature dependence of channel mobility and smaller change in threshold voltage. Forming gas anneal after the POCl3 treatment further improves channel mobility up to about 101 cm2/Vs. Features and problems of P-doped oxide are summarized and the future challenges are described.