Computer Stimulation On Solar Cell With Structure Of Epitaxial Layer On Low-price Silicon

The high production cost of solar cell restricts the development of the solar cell. For the purpose of reducing the cost of solar cell, the a-Si (p)/poly-Si (n)/c-Si (n+) solar cell was presented. In this paper, the electrical parameters of polycrystalline film such as the average carrier concentration, mobility and resistivity are calculated based on the theory of the polycrystalline silicon film. Then, AFORS-HET is used to simulate the performance of the a-Si (p)/poly-Si (n)/c-Si (n+) solar cell. It is calculated that the effect of the thickness, grain size and trap density of the polycrystalline film on the performance of the a-Si (p)/poly-Si (n)/c-Si (n+) solar cell.The results show that:(1)With the thickness of polycrystalline silicon film increase, the performance parameters of solar cell, such as Voc, Jsc, fill factor and efficiency, firstly decreases and then increases.When grain size is 10μm and thickness is 50μm, efficiency is maximum. Choosing the suitable thickness can save silicon materials, reduce cost and achieve high efficiency.(2) When the thickness of polycrystalline silicon film is less than 10μm, with grain size of polycrystalline silicon film increase, performance parameters of solar cell such as Voc, Jsc, fill factor and efficiency increase. To improve the performance of solar cell, grain size of polycrystalline must be increased.(3)With the trapping state density increase, the performance parameters of the solar cell decrease.The thickness, grain size and trap destiny of polycrystalline film have a great effect on the performance of solar cell. Choosing the suitable thickness and grain size of polycrystalline silicon film is very important to reduce cost and achieve high efficiency. Improving the process to reduce the trapping state density can achieve better performance of the solar cell.