A New Observation of Strain-Induced Slow Traps in Advanced CMOS Technology with Process-Induced Strain Using Random Telegraph Noise Measurement

Abstract

In this paper, the hot-carrier induced oxide trap and its correlation with enhanced degradation in strained CMOS devices have been reported for the first time. First, the I(D)-RTN (Drain Current Random Telegraph Noise) has been employed to study the HC stress induced slow oxide traps in strained nMOSFETs and pMOSFETs. Secondly, different behavior of the slow traps in nMOSFET and pMOSFET has been observed. Results show that the vertical compressive strain generates extra oxide defects and induces more scattering after the HC stress in CESL nMOSFET. This vertical strain in CESL, also contributes to a non-negligible amount of extra device degradation. While, SiGe S/D pMOSFET shows different behavior in that the compressive strain in this structure shows no impact on its reliability.