Suppressing Optical Losses in Solar Cells via Multifunctional and Large-Scale Geometric Arrays

The occurrence of optical loss on the surface of solar cells is inevitable due to the difference in the refractive index between air and glass, as well as the insufficient absorption of the active layer. To address this challenge, micron-sized geometry arrays, such as hemispheres and hemisphere pits, are prepared on quartz glass through the advanced indirect patterning technology of UV-LIGA. These geometric arrays exhibit multiple mechanisms for controlling light waves, including multiple rebounds, diffraction scattering, and total internal reflection. These synergistic effects suppress optical losses at the device's surface and prolong the photon propagation path in the active layer. After being patterned with this structure, the average transmittance and haze of the quartz glass reach 93.91% and 75%, respectively. Compared to their flat counterpart, the decorated monocrystalline silicon solar cells demonstrated an apparent improvement in photocurrent and produced a 7.2% enhancement in power conversion efficiency.