Method for making split dual gate field effect transistor

A method for making a semiconductor device with at least two gate regions, the method comprising:

• providing a substrate region including a surface;
• implanting a first plurality of ions into the substrate region at a first dosage level to form a protective layer;
• implanting a second plurality of ions into the substrate region at a second dosage level to form an adjustment layer;
• forming a source region in the substrate region by at least implanting a third plurality of ions into the substrate region at a third dosage level, the third dosage level being higher than the first and second dosage levels, the source region partially overlapping the protective layer and the adjustment layer;
• forming a drain region in the substrate region by at least implanting a fourth plurality of ions into the substrate region at a fourth dosage level, the drain region and the source region being separate from each other, the fourth dosage level is higher than the first and second dosage level;
• depositing a gate layer on the surface;
• forming a first gate region and a second gate region on the surface;
• wherein the forming a first gate region and a second gate region includes forming an insulation region on the surface by at least removing a part of the gate layer, the first gate region and the second gate region being separated by the insulation region;
• wherein:
• the first gate region is capable of forming a first channel in the substrate region, the first channel from the source region to the drain region;
• the second gate region is capable of forming a second channel in the substrate region, the second channel from the source region to the drain region.