A comparative study of reliability and performance of strain engineering using CESL stressor and mechanical strain

Effects of a stressor nitride layer on device performance and reliability are investigated. To decouple intrinsic mechanical stress and process-related effects, device characteristics under mechanical bending stress and stressor layers were compared. The compressive stressor device exhibits improved initial interface quality, although slightly degraded reliability characteristics, due to increased hydrogen passivation of the dielectric/substrate interface. Thereby, the hydrogen passivation in the interface is found to be a primary cause of the difference in reliability characteristics.