Infrared Spectroscopic Study of Hydrogenation Process of Si(100) Surface During Hydrogen Plasma Exposure

We used infrared spectroscopy to investigate the hydrogenation process of Si(100) surface by hydrogen plasma exposure with the substrate bias of -150 V at different temperatures between room temperature and 200 °C. An amorphous layer is generated by exposure at room temperature, following the generation of both hydrogen insertion states and hydrogen terminated vacancies. By increasing the substrate temperature during exposure, generation of SiH2 in the amorphous layer is suppressed. Si vacancy terminated with three hydrogen atoms (VH
₃
) is prominently generated by the plasma exposure at more than 150 °C, following generation of two hydrogen insertions into the Si-Si bonds (IH
₂
).