Effect of n Doped Layers in an Amorphous Silicon Top Solar Cell on the Performance of "Micromorph" Tandem Solar Cells
非晶硅顶电池中的n型掺杂层对非晶硅/微晶硅叠层太阳电池性能的影响

Pin/pin "micromorph" tandem solar cells were deposited by very high frequency plasma enhanced chemical vapor deposition (VHF-PECVD).Tunnel recombination junctions of the "micromorph" tandem solar cells consisting of two microcrystalline-doped layers with a defect rich interface were developed.While the solar cells performed reasonably well under AM 1.5 lights,we found through spectral response measurements that the first deposited cell of the tandem structures was leaking under low light conditions.The insertion of a thin protection layer of n-type amorphous silicon is presented in this paper.The results shown that the introduced n-type amorphous silicon could improve the leakage phenomenon.The leakage phenomenon disappeared when the thickness of the n-type amorphous silicon was 6nm,leading to an increase in open-circuit voltage.The open-circuit voltage increased from 1.27 to 1.33V and FF increased from 60% to 63%.