A semiconductor structure and a method for fabricating the semiconductor structure provide a field effect device structure. The field effect device structure includes a gate electrode located over a channel region within a semiconductor substrate that separates a plurality of source and drain regions within the semiconductor substrate. The channel region includes a surface layer that comprises a carbon doped semiconductor material. The source and drain regions include a surface layer that comprises a semiconductor material that is not carbon doped. The particular selection of material for the channel region and source and drain regions provide for inhibited dopant diffusion and enhanced mechanical stress within the channel region, and thus enhanced performance of the field effect device.