550 3 In, Ga, Se Cu / (In + Ga) 0.8 CIGS Characterization of CIGS Solar Cell Process and Cell

The conductive Cu nano ink can be printed by ink-jet printing on polyimide substrate, and then photo-sintered in the air atmosphere within 1 second. In the present work, the spin coated Cu nano ink on polyimide substrate was photo-sintered under various conditions. The microstructures of the sintered Cu films were observed by scanning electron microscopy. Neck formation and grain growth were promoted with increasing of irradiation energy. The mechanism of the photo-sintering process is studied in comparison with a firing process in nitrogen atmosphere. The obtained Cu film by photo-sintering process has low resistivity of 3μΩ·cm and good adhesion vs. polyimide. In contrast, the sintered Cu film by firing process in nitrogen atmosphere has high resistivity of 15μΩ·cm and poor adhesion. It was suggested that good adhesion between Cu film and polyimide is contributed by the bite into the substrate.

Dendritic electrodes composed of yttria stabilized zirconia (YSZ) and nickel oxide (NiO) were successfully fabricated by using micro stereolithography for solid oxide fuel cells. The dendritic structures constructed from micrometer order ceramic rods with coordination numbers of 4, 6, 8, and 12 were designed in computer graphic application. Range of aspect ratios determined by rod diameters and lengths was varied from 0.75 to 3.00. Gaseous fluid permeabilities in the dendritic lattices were simulated and visualized by using finite volume methods. The dendritic lattice with 12 coordination number was verified to exhibit the largest surface area and smooth fluid transparent characteristics. The optimized dendritic structure of 100 μm in lattice constant was fabricated by using micro stereolithography. Composite precursors of acrylic resin and nanometer sized YSZ and Ni particles were dewaxed at 600 °C for 2 hs and sintered at 1350-1450 °C for 2 hs. Microstructures were observed by using optical and scanning electron microscope.