PHOTOINDUCED DEPOSITION OF ALUMINUM THIN-FILM ON SILICON-NITRIDE AND OXIDE

Aluminum thin films were deposited via a photochemical surface reaction using dimethylaluminum hydride (DMAH) and a deuterium lamp on silicon wafers covered with silicon nitride and silicon oxide layers. Unlike deposition on uncovered silicon wafers, the dosing of DMAH at room temperature was not required. The dependence of the thickness of the deposit on substrate temperature, as well as on deposition time, was measured for photodeposition on the nitride layer. Scanning tunneling microscope images showed the formation of aluminum islands. An X-ray photoelectron spectroscopy (XPS) study indicated that the aluminum atom was bonded with carbon after adsorption at 230-degrees-C, and we speculated that the aluminum-methyl radical complex was photodissociated.