Low-resistive sulphur-treated ohmic contacts to n-type InAsSb

The authors present low-resistive ohmic contacts to lattice-matched n-type InAsSb on n-GaSb substrates, which are suitable for GaSb-based devices. Using wet chemical treatment as a surface preparation in order to remove the native oxides and evaporating Ti/Pt/Au metals sequentially, specific contact resistivities as low as 5.6×10−6 Ω cm2 without any annealing are obtained. The resistivity decreases to 3.7×10−6 Ω cm2 after annealing at 350°C for 90 s.