SiO_(x)N_(y)/SiN_(x)减反膜对双面PERC单晶硅太阳电池效率提升研究

Efficiency Improvement of Bifacial PERC Mono-crystalline Silicon Cells with SiO_(x)N_(y)/SiN_(x) as the Antireflection Coating

减反膜应用可降低气—固界面的菲涅尔反射,是提升光电转换效率晶硅太阳电池的有效手段之一。以商业化双面PERC单晶硅太阳电池(尺寸:182 mm×182 mm)为研究对象,以SiO_(x)N_(y)(1)/SiN_(x)(3)作为电池正面减反膜改善入射光子利用率。与传统SiN_(x)(4)减反膜相比,SiO_(x)N_(y)(1)/SiN_(x)(3)减反膜可显著降低300 nm~500 nm波段内光子反射率,短波段光子减反效果尤为明显。对应电池在标准测试条件下(AM1.5,1000 w·m^(-2),25℃)所测定平均光电转换效率可达23.227%,高于传统减反膜的电池效率(23.128%)。根据SERIS-V1.5软件对QE谱积分电流损失分析结果表明:基于SiO_(x)N_(y)(1)/SiN_(x)(3)减反膜电池电流损失相对采用传统SiN_(x)(4)减反膜电池,反射部分造成的电流损耗可降至0.867 mA·cm^(-2),且其他电学性能参数如开路电压及填充均得到一定程度改善,但并不实质影响电池背面效率。此外,基于SiO_(x)N_(y)(1)/SiN_(x)(3)减反膜电池规模生产终端EL测试良率与传统减反层电池相当,有望实现规模化生产。

With antireflection coating(ARC),the Fresnel reflection at the gas-solid interface can be reduced,which is one of the effective means to improve the performance conversion efficiency(PCE)of crystalline silicon solar cells.We proposed to use SiO_(x)N_(y)(1)/SiN_(x)(3)stacking layer as a front-side ARC to enhance the efficiency of incident photon in commercial bifacial PERC monocrystalline solar cells(182 mm×182 mm).Compared with the conventional SiN_(x)(4)ARC,the SiO_(x)N_(y)(1)/SiN_(x)(3)ARC is much stronger in suppressing the photon reflectivity over the range of 300-500 nm,especially in the shorter wavelength regime.The average PCE can be as high as 23.227%under standard test conditions(AM1.5,1000 W·m^(-2),25℃),as compared with that of the conventional SiN_(x)(4)ARC based cells(23.128%).According to the QE spectrum integrated current loss analyzed with the SERIS-V1.5 software,the current loss of the SiO_(x)N_(y)(1)/SiN_(x)(3)ARC cells was reduced to 0.867 mA·cm^(-2).Meanwhile,other parameters,such an open-circuit voltage and filling factor,can be also improved to a certain extent,while the rear-side PCE is not obviously affected.In addition,yield rate of the SiO_(x)N_(y)(1)/SiN_(x)(3)ARC cells that are checked with EL testing can match well with the conventional SiN_(x)(4)based cells,demonstrating the potential for large-scale production.