On the recovery of interface state in pMOSFETs subjected to NBTI and SHI stress

摘要

High temperature accelerated interface state (N_(it)) recovery is observed after the pMOSFETs experiencing negative bias temperature instability (NBTI) and substrate hole injection (SHI) stresses. It is found that there is hardly anyN_u recovery at room temperature, but much recovery happened with a rise in temperature. The recovery is due to the H species released by the breaking of Si_3≡Si-H, returning the Si/SiO_2 interface and passivating the Si_3=Si-. Some of the H species are trapped by oxide as-grown traps when diffusing to the gate and these will be activated by high temperature. So, more H species return the interface at higher recovery temperature which results in a large-scale recovery. A similar activation energy of generation and recovery is obtained, which supports the proposed recovery mechanism.