基于水汽气氛磷扩散技术的高薄层电阻制备方法研究

Research of the high sheet resistance preparation method based on diffusion in water vaporatmosphere

针对光伏工业界对磷扩散薄层电阻不断提升的需求,采用了在磷扩散工艺气氛中增加水汽的方法进行磷源扩散制备高薄层电阻,并通过实验对比两种扩散气氛下的掺杂浓度,少子寿命等表征。实验结果表明:在相同薄层电阻条件下,水汽气氛下掺杂剂的表面浓度降低,耗尽层的复合率减小,间隙态的金属杂质浓度降低,硅基体的少子寿命从6.27μs提升至7.16μs。由于掺杂剂浓度分布得到改善,降低了硅片的表面复合率和结区光生载流子的俄歇复合,使得水汽气氛扩散后硅片制备的太阳电池,光电转换效率提升0.1%。

According to the rising requirement of the emitter sheet resistance, the influence of water vapor atmosphere in phosphorus diffusion was studied,the characterization such as dopant profile and minority lifetime was compared in the experients. Experimental results reveal that the surface concentration of dopant was reduced in the water vapor atmosphere diffusion system, and the recombination velocities in depletion region was decreased, the concentration of interstitial metal impurities was reduced, thus the minority lifetime of silicon substrate increased from 6.27μs to 7.16μs, and meanwhile, the performance of the solar cell made from water vapor atmosphere diffusion system was optimized by the reduced surface doping concentration and Auger recombination velocities in emitter region, the opto-electronic efficiency were increased by 0.1%,respectively.