Transition metal oxide films prepared by pulsed laser deposition for atomic beam detection

Abstract

Resistivity of sintered metal oxides is known to change as a result of irradiation of atomic hydrogen, deuterium, nitrogen, and oxygen, but not as a result of irradiation of symmetrical diatomic molecules of these atoms. Thin films of nickel oxide, cobalt oxide and manganese oxide were formed by pulsed-laser deposition so as to enhance the sensitivity to atomic beams. The 4th harmonic of the Nd:YAG laser (λ=266 nm 4.8 J cm −2) was focused on sintered pellets, and thin films were deposited on pyrex glass substrates. The partial pressure of the oxygen gas P o2, and the substrate temperature, T g, are crucial parameters for the formation of transparent monoxide-like films. Optimum conditions were determined in the range of P o2=1.3×10 −4–1.3×10 Pa and T g=400–600°C. The films were characterized by X-ray photoelectron spectroscopy and X-ray diffraction. The monoxide-like films are found to be more sensitive to atomic beams than sintered oxides and even NiO single crystals.