基于不锈钢衬底CIGS太阳电池中Mo(N,O)薄膜的阻挡特性

Barrier performance of Mo(N,O)thin films in CIGS solar cells based on stainless steel substrates

不锈钢衬底铜铟镓硒(CIGS)太阳电池因其优异的光电转换效率和可弯曲特性而被广泛应用。但在制备CIGS薄膜过程中,衬底中的Fe元素会向CIGS薄膜扩散,导致电池性能下降。因此,需要在不锈钢衬底与Mo薄膜之间插入阻挡层来抑制Fe元素的扩散。采用反应磁控溅射方法制备了不同O_(2)流量条件下的Mo(N,O)薄膜,通过XRD、SEM及XPS研究了O_(2)流量对Mo(N,O)薄膜的晶体结构、微观形貌及元素组分的影响,二次离子质谱(SIMS)测试表明插入Mo(N,O)薄膜后,CIGS薄膜中Fe元素的相对强度由无阻挡层时的30 counts降至2 counts。通过优化选用O_(2)流量0.25 mL/min制备Mo(N,O)阻挡层,并制备了CIGS太阳电池,电流密度-电压(J-V)特性测试表明插入Mo(N,O)阻挡层后,电池效率由11.07%提高到14.34%。

Copper indium gallium selenium(CIGS)solar cells on stainless steel substrate are widely used in the photovoltaics community due to their excellent photoelectric conversion efficiency and flexibility.However,the Fe element will diffuse into the CIGS thin film from the stainless-steel substrate during the process of the preparation of the CIGS thin films,which resulting deteriorated the performance of the devices.Therefore,it is necessary to insert a barrier layer between the stainless steel substrate and the Mo thin film to inhibit the diffusion of the Fe element.Mo(N,O)thin films were produced using reactive magnetron sputtering with varying O_(2)flow rates.The influence of the O_(2)flow rate on the crystal structure,microscopic morphology,and elemental composition of the Mo(N,O)thin films was analyzed using an XRD,SEM,and XPS.Base on secondary ion mass spectroscopy(SIMS)testing results,the addition of Mo(N,O)thin film to the fabrication process of CIGS solar cells results in a reduction of Fe element's relative intensity in the CIGS thin film from 30 counts to 2 counts.Moreover,current density-voltage(I-V)characteristic test demonstrated an increase in the photovoltaic conversion efficiency for the flexible CIGS solar cell on a stainless steel substrate,from 11.07%to 14.34%,upon the addition of the Mo(N,O)thin film.