纳米颗粒墨水法制备的CIGSSe太阳能电池Cu含量调控与仿真模拟

Regulation of Copper Content and Simulation of CIGSSe So⁃lar Cells Prepared by Nanoparticles Ink Method

利用实验加仿真模拟的方法探究了纳米颗粒墨水中Cu含量(Cu/In+Ga,CGI)对铜铟镓硫硒(CIGSSe)太阳能电池性能的影响。首先,通过不同CGI墨水制备了CIGSSe太阳能电池器件,并对其吸收层进行了SEM,霍尔效应,以及拉曼光谱表征。表征结果表明:随着铜含量上升,吸收层晶体生长状况逐渐改善,且载流子浓度也逐步增大,但吸收层表面却存在越发明显的Cu2-xSe杂相。实验得出当吸收层的CGI为1.03时,器件的能量转换效率(PCE)最高,达10.09%。随后建立了对应的器件仿真模型,获得了具有不同CGI的CIGSSe器件的能量转换效率、器件能带与复合率分布情况,模拟结果表明:随着铜含量提高,载流子浓度上升,器件的开路电压有所提升,但当载流子浓度超过1018 cm-3时,吸收层表面出现了陡峭的能带弯曲现象,这增大了隧穿界面复合的发生,从而影响了器件的能量转换效率。因此,由实验与仿真模拟表明:制备CIGSSe薄膜太阳能电池时,有必要对Cu含量进行调控,从而达到促进晶体生长,减少界面复合,提升器件能量转换效率的目的。

An experimental and simulation approach was used to investigate the impact of copper(Cu)content(Cu/In+Ga,CGI)in nanoparticles ink on the performance of copper indium gallium selenide selenium(CIGSSe)solar cells.Firstly,CIGSSe solar cell devices was prepared using differ-ent CGI inks and their absorber layers were characterized using scanning electron microscopy(SEM),Hall effect measurements,and Raman spectroscopy.The results showed that as the copper content in-creased,the crystal growth of the absorber layer gradually improved,and the carrier concentration in-creased.However,the Cu2-xSe phase became more prominent on the surface.The best experimental conversion efficiency was achieved with CGI of 1.03,and a photovoltaic conversion efficiency of 10.09%.Then a corresponding device simulation model was established to obtain the photoelectric conversion performance,device band structure,and recombination rate distribution of CIGSSe devic-es with different CGI.The simulation results showed that as the copper content increased and the carri-er concentration increased,the open-circuit voltage of the device increased.However,when the carri-er concentration exceeded 1018 cm-3,a steep band bending phenomenon appeared on the absorber layer surface,which increased the occurrence of tunneling interface recombination,thereby affecting the de-vice efficiency.Therefore,both the experimental and simulation results suggested that it could be nec-essary to control the Cu content when preparing CIGS thin-film solar cells to promote crystal growth,reduce interface recombination,and improve device efficiency.