Study of electron mobility on silicon with different crystalline orientations

nMOSFETs with different channel directions are fabricated on (100), (110), (111) and (112) silicon substrates, in order to study electron mobility on (112) substrates. Electron mobility is extracted and compared between different crystalline orientations. Results show that electron mobility on (112) substrates is higher than that on (110) substrates but lower than that on (100) substrates. Electron mobility on (112) substrates is channel orientation depended, which is different from that on (111) substrates. Electron mobility on (112) substrates is close to that on (111) substrates with current flow along <;110> direction, and is close to that on (110) substrates with current flow along <;111> direction.