Field effect transistor for reducing hot carrier damage and methods for forming the same

Abstract

A field effect transistor includes a source-side doped well, a drift-region well, a source region, a drain region; a shallow trench isolation structure including a first portion overlying the drift-region well and laterally spaced from the source-side doped well; a gate dielectric layer; a gate electrode overlying the gate dielectric layer; and a proximal doped layer stack embedded within the drift-region well and interposed between the source-side doped well and the first portion of the shallow trench isolation structure. Proximal doped semiconductor layers of the proximal doped layer stack have different average atomic concentrations of dopants of the second conductivity type.