Extremely thin semiconductor on insulator semiconductor device with suppressed dopant segregation

A method of fabricating a semiconductor device comprising:

• providing a handling substrate;
• forming a first semiconductor layer on the handling substrate;
• epitaxially growing a second semiconductor layer on the first semiconductor layer, wherein the composition of the second semiconductor layer is different than the first semiconductor layer and the second semiconductor layer has a thickness of less than 20 nm;
• forming a first gate structure on a first surface of the second semiconductor layer;
• forming a source region and a drain region adjacent to the first gate structure, wherein at least a portion of dopant of the source and drain regions is present in at least the second semiconductor layer;
• removing the handling substrate and the first semiconductor layer to expose a second surface of the second semiconductor layer that is opposite the first surface of the second semiconductor layer;
• and
• forming one of a second gate structure or a dielectric region in contact with the second surface of the second semiconductor layer.