Design and formation of SiC (0001)/SiO2interfaces via Si deposition followed by low-temperature oxidation and high-temperature nitridation

Abstract

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.