This work focuses on a simple template assisted approach for fabricating I-III-VI semiconductor nanowire arrays. Vertically aligned nanowires of p-CIS of controllable diameter and thickness are electrodeposited, from an acidic electrolyte solution, inside porous aluminum templates using a three electrode set up with saturated calomel electrode as the reference. AAO template over ITO-glass was used as starting template for the device fabrication. The deposited CIS is annealed at different temperatures in a reducing environment (95% Ar+ 5% H2) for 30 minutes. X-ray diffraction of the nanowires showed nanocrystalline cubic phase structures with a strong orientation in the <112> direction. The effective bandgap of the deposited CIS nanowires determined using the Near Infrared (NIR) Spectrometer was found to be 1.07eV. The type of CIS electrodeposited inside the porous alumina template is determined to be p-type from the Schottky diode obtained with ITO-CIS-Au structure. Schottky diodes were characterized and analyzed at room temperature.

The use of size and shape tunable quantum confinement nanocrystals has many potential applications for use in semiconductors, optics and sensors. The synthesis of lead sulfide (PbS) and copper indium diselenide (CuInSe���) nanoparticles are of particular interest for use in semiconductor, optoelectronics and bio-medical applications. The continuous synthesis of lead sulfide (PbS) and copper indium diselenide (CuInSe���) nanocrystals was undertaken in this work. Quality colloidal nanocrystal synthesis requires three components: precursors, organic surfactants and solvents. The synthesis of the nanocrystals can be thought of as a nucleation event, followed by a subsequent growth period. Both the nucleation and growth rates were found to be dependent upon factors such as temperature, growth time, and precursor concentration. For a continuous flow system the residence time (at nucleation and growth conditions) was also found to be important. In order to separate the nucleation and growth events, injection techniques were employed to achieve rapid nucleation of nanocrystals with final size dictated by the growth temperature and/or residence time through the growth zone of the reaction system. Experimental parameters to investigate the size, shape, and composition of synthesized nanocrystals included injection temperature, growth temperature, residence time, and concentration of organic surfactants. Size tunability was accomplished for both PbS and CuInSe��� nanocrystals where particle sizes less than 10 nm were achieved and the resulting nanocrystal compositions were found to be at the approximate stoichiometric ratios for both PbS and CuInSe���. The materials used for the process tubing and pumps were found to be important as chlorinated reaction byproducts were found to react with the stainless steel tubing and pump heads. Post processing was also found to be important in order to remove any possible reaction by-products and residual precursors from the surface of synthesized nanocrystals. When at least one dimension of the nanocrystal approaches the exciton Bohr radius, the bandgap for the nanocrystal increases. UV-VIS spectroscopy was used to optically characterize synthesized PbS nanocrystals from our continuous flow synthesis. The absorption spectra for the particles demonstrated an absorption onset showing a large blueshift compared to that of bulk PbS. The blueshift matches closely with literature reports of the quantum confinement effect that would be desired when synthesizing PbS nanoparticles at diameters that are less than the PbS exciton Bohr radius of 18 nm. / Graduation date: 2013