Physical understanding of electron mobility in asymmetrically strained InGaAs-on-insulator metal-oxide-semiconductor field-effect transistors fabricated by lateral strain relaxation

In this paper, we fabricated asymmetrically tensile-strained In0.53Ga0.47As-on-insulator (-OI) metal-oxide-semiconductor field-effect transistors (MOSFETs) using a lateral strain relaxation technique. A stripe-like line structure, fabricated in biaxially strained In0.53Ga0.47As-OI can lead to the lateral strain relaxation and asymmetric strain configuration in In0.53Ga0.47As-OI with the channel width of 100 nm. We have found that the effective mobility (μeff) enhancement in In0.53Ga0.47As-OI MOSFETs with uniaxial-like asymmetric strain becomes smaller than that in In0.53Ga0.47As-OI MOSFETs with biaxial strain. We have clarified from a systematic analysis between the strain values and the μeff characteristics that this mobility behavior can be understood by the change of the energy level of the conduction band minimum due to the lateral strain relaxation.