Fabrication of polycrystalline silicon solar cells showing high efficiency

Abstract

The paper presents a methodology for fabrication of low-costing silicon solar cells with an efficiency of 10%. A polycrystalline silicon wafer, size 100×100 mm and thickness 450 µm, was doped with phosphorus using POCl₃ as the dopant. While, the backside (p-side) of the wafer was printed with a paste of Ag+Al in the ratio of 25 : 1, the front side (n-side) was printed with a paste of silver. It was fired at 720°C for better ohmic contact. Chemical vapour deposition (CVD) method was adopted for antireflection coating. Pure oxygen gas was bubbled through a solution of TiCl₄ at 200°C. The fabricated cells gave a significant increase in efficiency in terms of open circuit voltage (V) 560 mV, short circuit current (I) of 2·7 amp, and fill factor of 0·73. The methods used are inexpensive, and suitable for production of efficient silicon solar on a commercial basis.