Solar Energy Materials and Solar Cells, Vol.90, No.7-8, 1098-1104, 2006
Hydrogenated nanocrystalline silicon p-layer in amorphous silicon n-i-p solar cells
This paper describes an investigation into the impacts of hydrogenated nanocrystalline silicon (nc-Si:H) p-layer on the photovoltaic parameters, especially on the open-circuit voltage (V-oc) of n-i-p type hydrogenated amorphous silicon (a-Si:H) solar cells. Raman spectroscopy and transmission electron microscopy (TEM) analyses indicate that this p-layer is a diphasic material that contains nanocrystalline grains with size around 3-5nm embedded in an amorphous silicon matrix. Optical transmission measurements show that the nc-Si:H p-layer has a wide band gap of 1.9eV. Using this nanocrystalline p-layer in n-i-p a-Si:H solar cells, the cell performances were improved with a V-oc of 1.042V, whereas the solar cells deposited under similar conditions but incorporating a hydrogenated microcrystallme silicon (pc-Si:H) p-layer exhibit a V-oc of 0.526 V. (c) 2005 Elsevier B.V.. All rights reserved.