The Ohmic contact of n-GaSb with a Mo diffusion barrier

Ohmic contacts to n-type GaSb have been investigated. Some drawbacks are associated with conventional Ni/AuGe/Au Ohmic contact of n-GaSb, so we propose to add a Mo diffusion barrier between AuGeNi and Au layer and carry out the structure fabrication experiment. The results show that the new metallization decreases the specific contact resistance and can be annealed at wide temperature range. It is more important that the introduction of Mo inhibits effectively the in-diffusion of atoms by the analysis of AES. It also makes the new metallization have a better surface morphology, wider temperature range and benefit for the stability of the devices.