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Ion energy of laser plasmas produced by repeated nanosecond pulsed laser ablation of graphite is measured by time-of-flight (TOF) spectrometry and retarding potential analysis. An Nd:YAG laser with λ=1064 nm wavelength is incident toward the center of a cylindrical graphite target while the target is rotated along its axis. Ion energy distributions are measured via TOF spectroscopy. TOF signals show a decrease in the ion peak current by half followed by shifting of the signals by 4 μs toward later times after 10 000 laser shots. An ion energy decrease of 200 eV was measured from the retarding potential analysis.

The effect of varying the water vapor content in a DC magnetron sputtering process was investigated for zinc oxide film formation. The plasma parameters near the substrate surface were measured using a single Langmuir probe, and the deposited films were characterized using X-ray diffraction, X-ray reflectivity, optical transmittance, and 4-point probe methods. In the region near the substrate surface, the addition of water changes the plasma properties, and the measured plasma parameters showed the changes corresponding to the transition in the film growth mechanism from Zn to ZnO. Depositing at 40% water content resulted to a highly transparent film with a ρ of 1.20 Ω cm. The band gap of films deposited at 40 to 100% settings ranged from 3.36 to 3.34 eV, which matches the expected shallow hydrogen donor doping in ZnO.