Method of manufacturing semiconductor device including ashing of photoresist with deuterium or tritium gas

摘要

A method of manufacturing a semiconductor device comprises placing a semiconductor substrate in an ashing chamber, the semiconductor substrate having a gate, a silicon nitride gate sidewall offset spacer or a silicon nitride gate sidewall pacer formed thereon, and a photo resist residue remaining on the semiconductor substrate, introducing a gas mixture including D₂ or T₂ into the ashing chamber, and ashing the photo resist residue using a plasma that is formed from the gas mixture. The gas mixture can include a deuterium gas or a tritium gas having a volume ratio ranging between about 1% and about 20%. Embodiments can reduce Si recess and the loss of silicon nitride thin film during ashing.