is suitable for nmosfets furthermore fig3 shows the conduction band and valence band of tensile strained silicon on relaxed silicon germanium by curves 6 and 7 respectively electrons are confined in the tensile strained silicon which has high electron mobility and this material system is suitable for nmosfets with the three material systems the channel could either be a surface channel or a buried quantum well channel in fig1 3 the ordinate represents energy and the abscissa represents depth the cross sectional schematic for the first embodiment of a sige based lateral pmosfet 78 is shown in fig4 the device has the following structural characteristics 1 the drain is n type tensile strained silicon 82 2 the body is p type relaxed sige 81 and the doping level is adjusted to achieve desirable the threshold voltage 3 the source is n type tensile strained silicon 83 4 the channel is tensile strained si 84 and there is no hetero barrier along the current flow direction shown by arrow 93 the channel forms a heterojunction with the body 81 at the interface 805 which functions to provide a band offset as shown in fig3 to confine electrons in the si channel 84 the channel is typically autodoped by the layer below thus the channel region over the body 81 is autodoped p type while the channel region over the source 83 and drain 82 are doped n type there are other ways to provide the desired doping in the channel layer and.