Extraction of Interface Trap Density Through Synchronized Optical Charge Pumping in Gate-All-Around MOSFETs

Abstract

The number of interface traps ( ${N}_{\textit {it}}$ ) in a gate-all-around (GAA) MOSFET that harnesses an inherent floating body, was analyzed by using the synchronized optical charge pumping (SOCP) technique. By synchronizing control timing between the MOSFET operation and optical stimulation by light, holes generated by light illumination dominantly vanished, due to surface recombination with interface traps, rather than bulk recombination in a silicon nanowire and source/drain back-diffusion. This SOCP characterized the ${N}_{\textit {it}}$ without the aid of any additional specified test structure. To demonstrate an application, the amount of interface traps originating from off-state stress was quantitatively extracted by the SOCP.