Low-Frequency Noise Characteristics of SiGe p-Channel Metal–Oxide–Semiconductor Field-Effect Transistors with High-Compressive Interlayer-Dielectric-SiNx Stressing Layer

Abstract

Low-frequency noise characteristics of SiGe p-channel metal–oxide–semiconductor field-effect transistors (PMOSFETs) with a highly compressive interlayer-dielectric-SiNx (ILD-SiNx) stressing layer are studied. Experimental results predict that the SiGe-channel device with a highly compressive stressing layer has a lower noise magnitude than the conventional SiGe-channel and bulk-Si devices, irrespective of strain strength in our PMOSFET devices. This noise improvement can be attributed to the lower effective oxide trap densities. After extracting the effective trap densities from the low-frequency noise data, we found that the high-compressive SiGe-channel device has lower trap densities. The lower trap densities may be due to the passivation of gate dielectric defects by hydrogen species during high-compressive interlayer-dielectric-SiNx (ILD-SiNx) stressing layer deposition.