Patent ID: 6884688

Claim:
A method of producing a MOS transistor, which comprises the following steps: forming a source zone and a drain zone each with a highly doped region of a first conductivity type in a substrate region of a second conductivity type, opposite to the first conductivity type; subsequently to forming the highly doped region of the drain zone and the highly doped region of the source zone, implanting doping atoms of the first conductivity type in the region of the drain zone and the source zone such that a local position of a pn junction between the drain zone and the substrate is vertically shifted; forming a gate oxide region and a gate electrode above a channel region between the drain zone and the source zone; forming LDD regions; implanting the LDD regions in the substrate beneath the gate oxide region after forming the LDD regions; and forming at least two heavily doped zones between the LDD regions and the gate oxide region.