Preparation of n- and p-InP Films by PH3 Treatment of Electrodeposited In Layers

Thin InP layers have been prepared by electrodeposition of In films on Ti substrates (ca. 2 mg cm(-2) of In) and their annealing in PH3 flow. The obtained material, characterized by scanning electron microscopy-energy dispersive x-ray analysis and x-ray diffraction techniques, shows uneven substrate coverage but good crystallinity. Photoelectrochemical investigations in acidic polyiodide medium show significant n-type photoactivity for the samples prepared from a nominally pure In layer. A p-type photoactivity is obtained depositing a small amount of Zn on top of the In layer prior to annealing. Results are compared with those obtained preparing InP layers on Ti by a conventional metallorganic chemical vapor deposition technique.