A Study of Strain Engineering Using CESL Stressor on Reliability Comparing Effect of Intrinsic Mechanical Stress

The 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 an increased hydrogen passivation of the dielectric/substrate interface. Thereby, the hydrogen passivation in the interface is found to be the primary cause of the difference in reliability characteristics.