Abstract
SPA solar cell structure combining a-Si and poly-Si thin film has been developed in our group and the efficiency of the SPA structure obtained by simulation was 17.04%. Fabricating SPA solar cell requires p-type and n-type amorphous silicon layers with high doping concentration and device quality n-doped poly-Si thin films. In this study, our aim is to fabricate the p-doped and n-doped a-Si layers and fabricate a p-i-n amorphous silicon solar cell. Also we investigated on fabricating highly crystallized poly-Si thin films with large grains and columnar structure for the fabrication of new SPA structure. In the experiments, characterization of the Si films were carrird out by SEM, XRD, Raman spectra, 4-point probes, N&K, Hall measurement and UV-vis spectra. The resistivity, thickness, crystallinity of the thin film can be measured by these tools. We fabricated p-type a-Si films with a carrier concentration of 3.398E19 cm-3 and resistivity of 6.386E-1 Ω-cm. We also achieved the carrier concentration 1.727E20 cm-3 and resistivity 7.554E-2 Ω-cm of n-type a-Si:H thin film. We obtained 0.2412% efficiency of p-i-n amorphous silicon solar cell. We used hydrogen treatment and annealing method and layer by layer technique to improve the quality of poly crystal thin film. The crystallinity of poly crystal silicon obtained was 83% and the largest grain size was 360nm.