A MODEL FOR AMORPHOUS SOLAR CELL ANALYSIS
In the endeavour to improve conversion efficiency by the effective use of incident light, a detailed model which takes into account such optical processes as transmission, absorption and reflection in the cell has been tried out.
By the treatment of an amorphous solar cell as a multilayer interference filter and with suitable choices of antireflection coating materials and thicknesses of the various layers, an increase in the performance characteristics of the cells has been attained. When a double-layer antireflection coating is used, higher efficiencies can be achieved.
Efficiencies of about 16% for hydrogenated amorphous silicon (a-Si:H)/ polycrystalline silicon and of about 20% for a-Si:H/polycrystalline germanium tandem-type cells can be obtained. Our work shows that a device layout planned to optimize the use of incident light is needed to achieve good performances.