摘要
To absorb the infrared part of the solar spectrum more efficiently, narrow bandgap hydrogenated nanocrystalline germanium(nc-Ge:H) thin films were fabricated by radio frequency plasma enhanced chemical vapor deposition at a low temperature of 180 ℃.While the incubation layer of the nc-Ge:H was reduced to less than 5 nm by using the ultra-high hydrogen dilution, the negative photoconductivity behavior was still observed as the thickness of nc-Ge:H up to 30 nm.Therefore, as the best candidate for solar cells application, the nc-Ge:H(20 nm)/nc-Si:H(10 nm) periodic multilayer structure was prepared and used as the absorption layer of nc-Ge:H nip solar cells.More importantly, the spectral sensitivities extending into the wavelength of 1450 nm was achieved in the nc-Ge:H nip solar cells.In addition, the annealing for the nc-Ge:H nip solar cells was carried out.While the overall short circuit current density of device is improved after 500 ℃ annealing, the spectral sensitivities in the infrared region is decreased due to the the coalescence of Ge crystallites.
To absorb the infrared part of the solar spectrum more efficiently, narrow bandgap hydrogenated nanocrystalline germanium(nc-Ge:H) thin films were fabricated by radio frequency plasma enhanced chemical vapor deposition at a low temperature of 180 ℃.While the incubation layer of the nc-Ge:H was reduced to less than 5 nm by using the ultra-high hydrogen dilution, the negative photoconductivity behavior was still observed as the thickness of nc-Ge:H up to 30 nm.Therefore, as the best candidate for solar cells application, the nc-Ge:H(20 nm)/nc-Si:H(10 nm) periodic multilayer structure was prepared and used as the absorption layer of nc-Ge:H nip solar cells.More importantly, the spectral sensitivities extending into the wavelength of 1450 nm was achieved in the nc-Ge:H nip solar cells.In addition, the annealing for the nc-Ge:H nip solar cells was carried out.While the overall short circuit current density of device is improved after 500 ℃ annealing, the spectral sensitivities in the infrared region is decreased due to the the coalescence of Ge crystallites.
引文
[1]Chang Li,Jian Ni,Xiaoxiang Sun,Xinyu Wang,Zhenglong Li,Hongkun Cai,Juan Li,Jianjun Zhang,J.Phys.D:Appl.Phys.,2017,50,045108.