,Evaluation of negative bias temperature instability in ultra-thin gate oxide pMOSFETs using a new o

• 作 者: Ji Zhi-Gang Xu Ming-Zhen Tan Chang-Hua
• 机 构: Department of Microelectronics, Peking University, Beijing 100871, China
• 出 处: 中国物理（英文版）
• 发表日期: 2006年10期
• 关键词: negative bias temperature instability proportional differential operator degrada

A new on-line methodology is used to characterize the negative bias temperature instability (NBTI) without inherent recovery. Saturation drain voltage shift and mobility shift are extracted by ID - VD characterizations, which were measured before stress, and after every certain stress phase, using the proportional differential operator (PDO) method. The new on-line methodology avoids the mobility linearity assumption as compared with the previous on-the-fly method. It is found that both reaction-diffusion and charge-injection processes are important in NBTI effect under either DC or AC stress. A similar activation energy, 0.15 eV, occurred in both DC and AC NBTI processes.Also degradation rate factor is independent of temperature below 90℃ and sharply increases above it. The frequency dependence of NBTI degradation shows that NBTI degradation is independent of frequencies. The carrier tunnelling and reaction-diffusion mechanisms exist simultaneously in NBTI degradation of sub-micron pMOSFETs, and the carrier tunnelling dominates the earlier NBTI stage and the reaction-liffusion mechanism follows when the generation rate of traps caused by carrier tunnelling reaches its maximum.