Rapid thermal annealing of indium phosphide compound semiconductors

Abstract

Rapid thermal annealing of ion implanted indium phosphide has been investigated. X-ray photoelectron spectroscopy was used to determine surface conditions of InP substrates cleaned with a degreasing procedure and subsequent treatment with either an iodic acid etch or an HF solution. The HF clean was found to remove the most oxygen from the surface. The indium phosphide substrates were implanted with Si at 100, 150, and 500 keV with doses of 5×1012, 1×1012, and 2×1013 cm−2, respectively. These implants were activated using rapid thermal annealing from 700 to 900 °C for 10–60 s in nitrogen or hydrogen ambients. Indium phosphide surfaces were protected during annealing by proximity contact with silicon wafers or by encapsulation with silicon nitride. Proximity contact was found to provide inadequate protection. Silicon was detected on the annealed InP surfaces and indium and phosphorus were detected on the silicon contact wafers. Indium phosphide substrates implanted with silicon at 100 keV with a dose of 5×1012 cm−2 showed a peak atomic concentration of 2×1017 cm−3 at a depth of 0.13 μm using secondary ion mass spectroscopy after encapsulation with silicon nitride and rapid thermal annealing at 700 °C for 30 s.