Characterization of sulfur passivated n-GaSb using transmission electron microscopy and the influence of passivation on ohmic contact resistance

Sulfur passivation of (100) n-GaSb was studied using transmission electron microscopy. An amorphous Ga-S layer was found to be formed with a thickness dependence on the duration of passivation. It was also found that the sulfur layer remains amorphous when annealed at 350°C for 10 min, but becomes nanocrystalline and enriched with Ga from the GaSb on annealing at 500°C for 20 min. The result show that sulfur passivation can inhibit reaction between a contact metallization and GaSb if used as a permetallization surface preparation.