Decrease in reflection loss at intermediate adhesive layer for mechanical stacking multi junction solar cells

We report decrease in reflection loss at the intermediate adhesive layer for mechanical-stack-multi-junction solar cells by increasing the refractive index of the intermediate adhesive layer. Samples of self-standing films of 30-nm-TiO₂-particle dispersed Cemedine and Si substrate/TiO₂ dispersed Cemedine/ Si structure were fabricated. Analysis of transmissivity of the samples revealed that the effective refractive index of the adhesive films was increased from 1.55 (pure Cemedine) to 1.66 by dispersing 100-mg-TiO₂ particles in 1000-mg Cemedine. The effective transmissivity at the intermediate layer was achieved to be 76 % for sample of Si/100-mg-TiO₂ dispersed Cemedine/Si, while it was 70 % for sample of Si/pure Cemedine/Si.