Advanced Low-Temperature–High-Pressure Hydrogen Treatment for Interface Defect Passivation in Si- and SiGe-Channel MOSCAPs

This work investigates a low-temperature and high-pressure (LTHP) hydrogen treatment in Si-channel and SiGe-channel metal–oxide–semiconductor capacitors (MOSCAPs). The LTHP hydrogen treatment can repair dangling bonds in the SiO2/Si and SiO2/SiGe interfaces to enhance device performance. Additional parameters of the treatment, including treatment pressure and time, are also investigated to better understand the reaction mechanisms, which further proves the effectiveness and potential of this supercritical fluid (SCF)-based treatment. In addition, this treatment will not damage the front structure and materials due to the relatively low process temperature (120 °C). Therefore, this treatment can be a nondestructive postannealing process. The results of extracting interface defect density ( ${D}_{{\text {it}}}{)}$ by the conductance method show that there is an ~51% reduction in the defect density after this posttreatment, a significant decrease. Finally, a TCAD simulation of different defect densities verifies the repair mechanism of deep-level defects.