Reliability of Nitrided Gate Oxides for N- and P-Type 4H-SiC(0001) Metal-Oxide-Semiconductor Devices

摘要

In this paper, we have investigated reliability of n- and p-type 4H-SiC(0001) metal-oxide-semiconductor (MOS) devices with N_2O-grown oxides and deposited oxides annealed in N_2O. From the results of time-dependent dielectric breakdown (TDDB) tests, it is revealed that the N_2O-grown oxides have relatively-high reliability (4-30 Ccm~(-2) for n- and p-MOS structures). In addition, the deposited SiO_2 on n- and p-SiC exhibited a high charge-to-breakdown of 70.0 and 54.9 C cm~(-2), respectively. The n/p-MOS structures with the deposited SiO_2 maintained a high charge-to-breakdown of 19.9/15.1 Ccm~(-2) even at 200 °C. The deposited SiO_2 annealed in N_2O has promise as the gate insulator for n-and p-channel 4H-SiC(0001) MOS devices because of its high charge-to-breakdown and good interface properties.