Polycrystalline Silicon Solar Cell Production, And Cuprous Oxide Thin Films

The thesis includes two parts. In the first part, we made some researches on Polycrystalline silicon solar cell production industry. In the second parts, We studied a new material used in solar cell with great potential.At present, the tendency of solar cell development is improving cell's efficiency and decreasing cost. The poly-silicon solar cell is one of the most potential solar cells in the future. In this part, we mainly researched how the process influence the cell performance according to the structure of poly-silicon in the industrial production of poly-silicon solar cell. The following conclusions were obtained:1. Studied the acid textured of poly-silicon surface structure by spectrum response system and scanning electron microscope. It proves, the poly-silicon can be reduced the reflectivity and gotten the uniform earthworm surface structure in the acid liquid 120s later, which HF:HNO3:H2O is 1:3: 2.7.2. Studied how different square resistances affected the cell performance by four-point probe andⅠ-Ⅴtest. The result proves that the cell can achieve the higher open circuit voltage and short circuit current when the square resistance is between 45-50Ω/□.3. Studied how to affect the cell performance in different etching conditions byⅠ-Ⅴtesting. That proves, higher radio frequency, long time etching, higher pressure and higher gas flow can damage the wafer surface, even endanger the p-n junction, then reduces the performance of cell.4. Studied the compactness of SiNx film, Hydrogen content and solar cell performance in different conditions by stripping film, fourier transform infrared spectroscopy andⅠ-Ⅴtesting. It proves that the poly-silicon surface passivation is related to the compactness of SiNx film, and the body passivation is mainly relate to the Hydrogen content of SiNx.5. Studied the Al back surface field with two different Al pastes by scanning electronic microscope andⅠ-Ⅴtesting. It proves that good Al back surface field can improve the performance of cell.Cu2O films were prepared by thermal evaporation of metallic Cu and annealing Cu films in air, the preparation work of Cu2O films applicated in heterojunction solar cell have been made. The structures, elements and topographies of the as-deposited film and the films annealed at different temperatures were studied by X-ray diffraction(XRD), energy dispersive X-ray spectroscopy(EDX), and atomic force microscopy(AFM). The following conclusions were obtained:1. Cu2O film has been obtained by annealing the as-deposited Cu film at 200℃for 30 minutes.2. Resistance of the Cu2O film is 0.22Ωcm measured by four-point probe.3. Optical property of the Cu2O film was studied using ultraviolet-visible spectrophotometer(UV-vis) and its optical band gap is 2.4eV.