Nitrogen doping of TiO(2) films (N:TiO(2)) has been shown to improve the visible-light sensitivity of TiO(2), thereby increasing the performance of both photovoltaic and photocatalytic devices. Inductively coupled rf plasmas containing a wide range of nitrogen precursors were used to create nitrogen-doped TiO(2) films. These treatments resulted in anatase-phased materials with as high as 34% nitrogen content. As monitored with high-resolution X-ray photoelectron spectroscopy spectra, the nitrogen binding environments within the films were controlled by varying the plasma processing conditions. XPS peak assignments for multiple N 1s binding environments were made based on high resolution Ti 2p and O 1s XPS spectra, Fourier transform infrared spectroscopy (FTIR) data, and literature N 1s XPS peak assignments. The N:TiO(2) films produced via plasma treatments displayed colors ranging from gray to brown to blue to black, paralleling the N/Ti ratios of the films. Three possible mechanisms to explain the color changes in these materials are presented.

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Thin films of CuInS 2 were grown on various substrates at a temperature of 523 K from two metal-organic precursors using radiofrequency plasma enhanced chemical vapor deposition (PECVD). Two precursor molecules, with different solubility properties, were dissolved in appropriate solvents and sprayed into the plasma region in the PECVD chamber. The resulting films were examined for atomic composition, growth rate, crystalline orientation, and uniformity. Films made from each precursor differed in thickness, atomic composition, and crystallinity. The uniformity of the film was fairly good from near the edge to the center of the substrate, and evidence for a chalcopyrite-like structure was found in several samples deposited from one of the precursor molecules.

Understanding the gas‐phase and surface chemistry of NHx species in pulsed NH3 plasmas can lead to optimized plasma conditions for nitriding metal oxide surfaces such as TiO2. Gas‐phase densities and surface reactions of NH and NH2 in pulsed NH3 plasmas used to nitride TiO2 surfaces were explored by systematically varying peak plasma power and pulsing duty cycle. Results from laser induced fluorescence and optical emission spectroscopy studies reveal interconnected trends of gas‐phase densities and surface reactions. Divergent trends in NH, NH2 Hα, Hγ, N, and N densities found in short pulse plasmas are explained by plasma pulse initiation and afterglow effects. NH2 and NH surface scatter coefficients were measured with the imaging of radicals interacting with surfaces technique as a function of plasma parameters, including pulse sequence. Results show NHx species primarily scatter off of TiO2 and are correlated to NH gas phase densities. magnified image