Buried channel semiconductor device including energy barrier modulation region(s)

A method of forming a semiconductor device, the method comprising:

• forming a channel covering surface region in a doped region in a semiconductor substrate and at an upper surface of the semiconductor substrate, the doped region being doped with a first conductivity type, the channel covering surface region being doped with a second conductivity type opposite from the first conductivity type;
• forming a gate structure over the upper surface and over the channel covering surface region;
• forming a first energy barrier modulation region in the doped region and at the upper surface of the semiconductor substrate, forming the first energy barrier modulation region including implanting a first dopant of the first conductivity type in the semiconductor substrate underlying the gate structure;
• and
• forming a first source/drain region in the doped region, the first source/drain region being doped with the second conductivity type, the first energy barrier modulation region being laterally between the first source/drain region and the channel covering surface region.

A semiconductor device comprising:

• a first p-type source/drain region in an n-type well in a semiconductor substrate, the semiconductor substrate having an upper surface;
• a first n-type region in the n-type well and at the upper surface of the semiconductor substrate;
• a p-type region in the n-type well and at the upper surface of the semiconductor substrate;
• and
• a gate structure over the upper surface, the first n-type region and the p-type region underlying the gate structure, the first n-type region being laterally between the first p-type source/drain region and the p-type region.