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

Abstract

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 Â 10 26 V cm 2 without any annealing are obtained. The resistivity decreases to 3.7 Â 10 26 V cm 2 after annealing at 3508C for 90 s.

Ultra-low resistive GaSb/InAs tunnel junctions

“…Then, the samples were immersed in an aqueous (NH 4 ) 2 S solution in order to exchange the oxygen with sulfur and passivate the dangling bonds at the surface. A more detailed description of the procedure can be found in [9]. The wet-chemical passivation step was followed by an immediate loading of the samples into a metal-deposition chamber.…”

Electrically pumped continuous-wave vertical-cavity surface-emitting lasers at ∼2.6 μm

“…The latter is dominating in such devices, despite the fact that the current spreads out in the bottom mirror. Here, the top p-contact, 14 the top lateral current spreading layer for the annular contact, 15 and the tunnel junction 16 contribute by about 0.9, 5.6, and 9.2 ⍀, respectively, to the total calculated resistances. Therefore, the rest of the total series resistance can be attributed to the epitaxial bottom mirror.…”