SiC金属氧化物半导体(MOS)器件中SiO_2栅氧化层的可靠性直接影响器件的功能。为了开发高可靠性的栅氧化层,将n型4H-SiC(0001)外延片分别在1 200,1 250,1 350,1 450和1 550℃5种温度下进行高温干氧氧化实验来制备SiO_2栅氧化层。在室温下,对SiC MOS电容样品的栅氧化层进行零时击穿(TZDB)和与时间有关的击穿(TDDB)测试,并对不同干氧氧化温度处理下的栅氧化层样品分别进行了可靠性分析。结果发现,在1 250℃下进行高温干氧氧化时所得的击穿场强和击穿电荷最大,分别为11.21 MV/cm和5.5×10-4C/cm~2,势垒高度(2.43 eV)最接近理论值。当温度高于1 250℃时生成的SiO_2栅氧化层的可靠性随之降低。 The reliability of the SiO 2 gate oxide in SiC metal oxide semiconductor (MOS) devices directly affects the device’s functionality. In order to develop a highly reliable gate oxide, an n-type 4H-SiC (0001) epitaxial wafer was subjected to a high-temperature dry oxygen oxidation test at temperatures of 1 200, 1 250, 1 350, 1 450 and 1 550 ° C, respectively SiO 2 gate oxide. The gate oxide layer of SiC MOS capacitor samples were tested for zero-time breakdown (TZDB) and time-dependent breakdown (TDDB) at room temperature. The gate oxide samples under different dry oxidation temperatures were subjected to Reliability analysis. The results showed that the breakdown field strength and breakdown charge were the highest at 11.22 MV / cm and 5.5 × 10-4 C / cm ~ 2, respectively. The barrier height (2.43 eV) The closest theoretical value. When the temperature is higher than 1 250 ℃, the reliability of the SiO 2 gate oxide layer is reduced.