A technique for direct wafer bonding of III–V materials utilizing a dry sulfur passivation method is presented. Large-area bonding occurs for GaAs/GaAs and InP/InP at room temperature. Bulk fracture strength is achieved after annealing GaAs/GaAs at 400°C and InP/InP at 300°C for times less than 12 h without large compressive forces. X-ray photoelectron spectroscopy measurements of the treated, bonded, and subsequently delaminated surfaces of GaAs/GaAs confirm that sulfide is present at the interface and that the oxide components show a reduced concentration when compared with samples treated with only an oxide etch solution.