利用PC2D二维模拟软件对选择性发射极晶体硅太阳电池(SE电池)进行了器件模拟和参数优化的研究.在对丝网印刷磷浆法制备的SE电池的实测典型电流-电压曲线实现完美拟合的基础上，全面系统地研究了栅线、基区、选择性发射区和背表面场层等的参数对电池性能的影响.模拟表明：基区少子寿命、前表面复合速度和背表面复合速度是对电池效率影响幅度最大的三个参数.在所研究的参数范围内，当基区少子寿命从50µs上升到600µs时，电池效率从18.53%上升到19.27%.低的前表面复合速度是使发射区方块电阻配比优化有意义的前提.要取得理想的电池效率，背表面复合速度需控制在500 cm/s以下.此外，对于不同的前表面复合速度，电池效率的最大值总是在50-90Ω/？的重掺区方阻、110-180Ω/？的轻掺区方阻的范围内取得.对不同的栅线数目，重掺区宽度与栅线间距之比为32%时，电池的效率最高.另外，在主栅结构保持较低面积比率的前提下，主栅数目的增加也可提高效率.最后，通过优化p型SE电池的效率可达到20.45%.%In this paper, device simulation and parameter optimization on crystalline silicon (c-Si) selective-emitter (SE) solar cell are performed by using PC2D two-dimensional simulator. On the basis of achieving perfect fitting to the measured I-V curve of a typical c-Si SE solar cell fabricated by screen printing phosphoric paste method, the effects of physical parameters of gridlines, base, selective emitter and back surface field layer on the optoelectronic performance of the SE solar cell are comprehensively and systematically investigated. Simulation results show that the base minority carrier lifetime, the front surface recombination velocity and the back surface recombination velocity are the three largest efficiency-affecting parameters. In the studied parameter range, when the base minority carrier lifetime rises from 50 µs to 600 µs, the cell efficiency increaes from 18.53% to 19.27%. Low front surface recombination velocity is the premise of making the optimization of selective emitter sheet resistance meaningful. To obtain an ideal efficiency, the back surface recombination velocity should be controlled to be under 500 cm/s. In addition, under different front surface recombination velocities, the maximum of cell efficiency is always achieved in a range of 50-90Ω/? heavily doped region sheet resistance and 110-180Ω/? lightly doped region sheet resistance. For different numbers of gridlines, when the radio of heavily doped region width to the gridline pitch equals 32%, the solar cell has the highest efficiency. Moreover, under the condition of low area radio of bas bar, increasing bus bar number appropriately can improve the efficiency. The efficiency of p-type SE solar cell reaches 20.45%after optimization.
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