Ultrathin silicon oxynitride interface material, tunnel oxide passivated structure and preparation methods and applications thereof

Abstract

An ultrathin silicon oxynitride interface material, a tunnel oxide passivated structure and preparation methods and applications thereof are provided. The ultrathin silicon oxynitride interface material is an SiON film with a thickness of 1 nm to 4 nm, and the percentage content of N atoms is 1% to 40%. Compared with silicon oxide, the diffusion rate of boron in the SiON film of the present disclosure is low, which effectively reduces the damaging effect of boron, improves the integrity of the SiON film and maintains the chemical passivation effect. The SiON film with high nitrogen concentration can noticeably lower the concentration of boron on the silicon surface so as to lessen the boron-induced defects. Furthermore, the SiON film has an energy band structure approximate to silicon nitride, which increases the hole transport efficiency and hole selectivity, and further improves the passivation quality and reduces the contact resistivity.