Preparation Of BZO Films Using LPCVD And Their Applications In Amorphous Silicon Thin Film Solar Cells

Zinc oxide(Zn O) as a n-type wide direct band-gap semiconductor material,with 3.37 eV band gap at room temperature, has excellent features with piezoelectricity, photoelectricity, pressure-sensitivity and others. It has high optical transparency, electrical conductivity, even comparable electrical and optical properties to that of ITO. And the raw materials of ZnO are abundant and non-toxic. Owing to those properties, ZnO thin film has been widely used in flat panel display electrodes, gas sensors and solar cells etc, and attracted wide attention and research. In order to optimize the performance of ZnO, accelerate the industrialization, and improve its efficiency and stability when it is applied to the solar cells, in this paper, we used low pressure chemical vapor deposition(LPCVD) technique to prepare ZnO:B thin film front electrode with light trapping structure on the glass, silicon and flexible substrate respectively, and it had been successfully applied to amorphous silicon thin-film flexible solar cells.Firstly, the ZnO:B(BZO) films were fabricated by low pressure chemica vapor deposition(LPCVD) technique, and the influence of deposition time, flow of boron doping and annealing conditions on the crystalline state, microscopic structure, electrical and optical properties of the films had been systematically discussed. It was found that the deposition time determined the growth thickness and the crystal orientation of BZO films, as well as effected the surface morphology and the grain size of BZO films;the doping of B would change the growth characteristics and the orientation temperature of the crystal growth of films, and broaden the optical band gap, at the same time, it could effectively reduce the resistivity of the films which was helpful to improve the electrical stability of films; the electrical and optical properties of films after annealing in the specific process had been greatly improved. The experimental results showed that :when the deposition time was 420 s, the flow of boron doping was 50 sccm, and DEZ/H2 O was 450/150, high-quality texture BZO thin films could be fabricated, and the electrical properties could be greatly improved after annealing 30 min at 200℃ in the H2 reduction atmosphere.Secondly, on the basis research of BZO thin films, the amorphous silicon thin film solar cells and modules had been prepared using the traditional silicon thin film solar cells production research equipment, in order to explore the preparation processing plan of the flexible transparent solar cells. Useing PECVD and R&D LSS laser equipment technique prepared the amorphoussilicon thin-film batteries on PI and flexible glass substrate with the ZnO: B instead of ITO for amorphous silicon thin film solar cells, as the window transparent electrode and back electrode. The open circuit voltage(Voc), the short circuit(Isc), the conversion efficiency(Eff) and the fill factor(FF) of the PI substrate battery were 0.799 V, 12.82 mA, 5.10% and 49.80% respectively, showing good light transmission; the open circuit voltage(Voc), the short circuit(Isc), the conversion efficiency(Eff) and the fill factor(FF) of the flexible substrate battery were 41.17 V, 478.1mA, 9.16% and 68.3% respectively.