TW270234B - Manufacturing process for lightly doped drain transistor device - Google Patents

Abstract

A manufacturing process for lightly doped drain transistor device, that is applicable to one substrate, comprises: forming the first insulation on the substrate, then performing the first ion implantation procedure in order to adjust threshold voltage of channel; forming the second insulation and the third insulation on the above first insulation in sequence; by lithographic process defining gate area pattern to expose designated gate area; through etching procedure etching the first insulation to the third insulation in order to make the above exposed gate area present one inverse-T trench; forming one gate oxide on substrate surface of the trench; forming one conducting layer on gate area of the above inverse-T trench and the third insulation; with conducting layer of the trench's two sides and the third insulation as mask, performing anti-punchthrough second ion implantation procedure; filling conducting material in trench above the above gate oxide, and generating one inverse-T gate electrode after etching back; removing the third insulation; removing the second insulation; with upper half part of the above gate electrode as mask, performing the third ion implantation procedure in order to form lightly doped source/drain and heavily doped source/drain simultaneously.