Design and formation of SiC (0001)/SiO2 interfaces via Si deposition followed by low-temperature oxidation and high-temperature nitridation

逆転の発想でSiCパワー半導体の高品質化に成功 --非酸化による酸化膜形成で高品質化10倍--. 京都大学プレスリリース. 2020-08-24.We report an effective approach to reduce defects at a SiC/SiO2 interface. Since oxidation of SiC may inevitably lead to defect creation, the idea is to form the interface without oxidizing SiC. Our method consists of four steps: (i) H2 etching of SiC, (ii) Si deposition, (iii) low-temperature (~750 °C) oxidation of Si to form SiO2, and (iv) high-temperature (~1600 °C) N2 annealing to introduce nitrogen atoms. The interface state density estimated by a high (1 MHz)–low method is in the order of 1010 cm−2 eV−1, two orders of magnitude lower than that of an interface formed by SiC oxidation