This letter investigates the negative-bias temperature instability (NBTI) degradation of p-channel low-temperature polycrystalline-silicon thin-film transistors (LTPS TFTs) under mechanical tensile stress. Experimental results reveal that the interface state density N it and grain boundary trap density N trap of tensile-strained LTPS TFTs are more pronounced than those of unstrained LTPS TFTs. Extracted density of states and conduction activation energy E a both show increases due to the strained Si-Si bonds, which implies that strained Si-Si bonds are able to react with dissociated H during NBTI stress. Therefore, NBTI degradation is more significant after tensile strain than in an unstrained condition.

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This paper investigates the channel hot carrier stress (CHCS) effects on gate-induced drain leakage (GIDL) current in high-k/metal-gate n-type metal-oxide-semiconductor field effect transistors. It was found that the behavior of GIDL current during CHCS is dependent upon the interfacial layer (IL) oxide thickness of high-k/metal-gate stacks. For a thinner IL, the GIDL current gradually decreases during CHCS, a result contrary to that found in a device with thicker IL. Based on the variation of GIDL current at different stress conditions, the trap-assisted band-to-band hole injection model is proposed to explain the different behavior of GIDL current for different IL thicknesses.

This letter systematically investigates the origin of gate-induced floating-body effect (GIFBE) in partially depleted silicon-on-insulator p-type MOSFETs. The experimental results indicate that GIFBE causes a reduction in the electrical oxide field, leading to an underestimate of negative-bias temperature instability degradation. This can be partially attributed to the electrons tunneling from the process-induced partial n + polygate. However, based on different operation conditions, we found that the dominant origin of electrons was strongly dependent on holes in the inversion layer under source/drain grounding. This suggests that the mechanism of GIFBE at higher voltages is dominated by the proposed anode electron injection model, rather than the electron valence band tunneling widely accepted as the mechanism for n-MOSFETs. Index Terms-EVB tunneling, gate-induced floating-body effect (GIFBE), negative-bias temperature instability (NBTI), silicon-on-insulator (SOI).

This letter investigates the impact of mechanical strain on gate-induced floating-body effect in partially depleted silicon-on-insulator p-channel metal-oxide-semiconductor fieldeffect transistors. The strained FB device has less NBTI degradation than unstrained devices. This behavior can be attributed to the fact that more electron accumulation induced by strain effect reduces the electric oxide field significantly during NBTI stress. Analysis of the body current (I B ) under source/drain grounded and floating operation indicates an increase in the anode electron injection and electron tunneling from conduction band which occur at the partial n + poly-Si gate and Si substrate, respectively. This phenomenon can be attributed to the bandgap narrowing which has been induced by the strain effect. Index Terms-Gate-induced floating-body effect (GIFBE), negative bias temperature instability (NBTI), silicon-on-insulator (SOI) MOSFETs, strained silicon.