根据多光束干涉原理，基于迭代算法，设计出用于异质结太阳能电池的异型分布布拉格反射（IDBR）结构。通过优化设计S1（500 nm+800 nm）、S2（500 nm+900 nm）、S3（500 nm+1000 nm）、S4（500 nm+800 nm+1000 nm）4种不同中心波长组合的异型布拉格背反射结构，发现S3具有最佳宽频带高反射效果，该异质结由两对非晶硅(32 nm)/氮化硅(61.78 nm)分布式布拉格反射（DBR）结构与三对非晶硅(64 nm)/氮化硅(123.57 nm) DBR结构组成。借助等离子体增强化学气相沉积(PECVD)的方法在异质结太阳能电池背面生长出具有五对α-SiH/SiN结构的异型布拉格反射镜，并测试其反射光谱曲线。实验证明该异型布拉格反射镜在730～1155 nm的光谱范围内反射率达到90%，在750~1110 nm波长范围内的反射率高达95％，从而具有显著提高太阳能电池的宽谱吸收效率的潜力，可以对1000~1155 nm范围内的红外光进行有效反射，增强电池对红外波段的吸收。

An irregularly shaped distributed Bragg reflector (IDBR) for hetero-junction with intrinsic thin layer (HIT) solar cells is designed and fabricated according to the theory of multi-beam interference and the method of iteration. Four types of IDBRs ［S1（500 nm+800 nm）, S2(500 nm+900 nm), S3(500 nm+1000 nm), S4(500 nm+800 nm+1000 nm)］ are compared and optimized. The result shows that the structure of S3 with two pairs of α-Si(32 nm)/SiN(61.78 nm) and three pairs of α-SiH(64 nm)/SiN(123.57 nm) is the most suitable structure. With the help of plasma enhanced chemical vapor deposition (PECVD), five pairs of α-SiH/SiN distributed Bragg reflector (DBR) multi-layer films is deposited on the back surface of HIT solar cell. The testing result shows that the reflectivity of S3 is larger than 90% in the wavelength range of 730～1155 nm, and larger than 95% in the wavelength range of 750~1110 nm, which shows the great potential for improving the absorption of light in the wavelength range of 1000~1155 nm (infrared wavelength range), and thus enhance the efficiency of HIT solar cell.