Nitride removal while protecting semiconductor surfaces for forming shallow junctions

Abstract

A method of removing silicon nitride over a semiconductor surface for forming shallow junctions. Sidewall spacers are formed along sidewalls of a gate stack that together define lightly doped drain (LDD) regions or source/drain (S/D) regions. At least one of the sidewall spacers, LDD regions and S/D regions include an exposed silicon nitride layer. The LDD or S/D regions include a protective dielectric layer formed directly on the semiconductor surface. Ion implanting implants the LDD regions or S/D regions using the sidewall spacers as implant masks. The exposed silicon nitride layer is selectively removed, wherein the protective dielectric layer when the sidewall spacers include the exposed silicon nitride layer, or a replacement protective dielectric layer formed directly on the semiconductor surface after ion implanting when the LDD or S/D regions include the exposed silicon nitride layer, protects the LDD or S/D regions from dopant loss due to etching during selectively removing.