Impact of Highly Compressive Interlayer-Dielectric-SiNx Stressing Layer on 1/f Noise and Reliability of SiGe-Channel pMOSFETs

Abstract

The 1/f noise and reliability of SiGe-channel pMOSFETs with a highly compressive contact-etching stop-layer (CESL) interlayer-dielectric-SiNx stressing layer have been studied in this letter. The SiGe-channel devices with a highly compressive CESL layer have higher drain current and lower 1/f noise than the conventional SiGe-channel and bulk-Si devices. However, the device reliability is degraded while integrating with the highly compressive CESL layer. By examining the effective oxide-trap densities under hot-carrier instability stress, we find that the incorporated hydrogen in gate oxide during CESL layer deposition may play an important role on the 1/f noise and device reliability.