Low resistance palladium/molybdenum based ohmic contacts to n-GaSb grown on GaAs

Low resistance ohmic contacts were fabricated on n-type GaSb grown by molecular beam epitaxy. N-type GaSb epilayers with different doping concentrations and thicknesses were fabricated and studied in order to investigate the current transport mechanism between the metal contacts and the semiconductor. Different metallization schemes were implemented to achieve the lowest possible contact resistance. Rapid thermal annealing was performed at various temperatures to achieve the optimal gold penetration into the GaSb epilayers for low resistance. Ohmic contact fabrication and electrical characterization are discussed in detail. The microstructure analysis of the semiconductor and metal contact interfaces was performed using cross-section transmission electron microscopy and energy dispersive spectroscopy. Specific contact resistances as low as 3×10-6 Ωcm2 were obtained. © 2014 American Vacuum Society.

Duke Scholars

Author Sayan Mukherjee Statistical Science