Back reflector texture and stability issues in high efficiency multijunction amorphous silicon alloy solar cells

The role of the back reflector texture on the initial and stabilized efficiency of high efficiency triple-junction triple-bandgap amorphous silicon alloy based cells has been investigated. The devices have been deposited on Ag/ZnO back reflector possessing three different textures. The performance of the bottom single-junction a-SiGe alloy n-i-p cell on the three textures has also been analyzed. The value of the short-circuit current density of the n-i-p cell initially increases and then decreases with increasing texture. Light soaking results show that the higher textures exhibit superior device stability. Degradation as low as 8% has been obtained on the triple-junction cells.