Grazing incidence measurements of polarized electroabsorption and light soaking effect on amorphous silicon based solar cells

Grazing-incidence measurements of polarized electroabsorption (EA) in p-i-n solar cells based on hydrogenated amorphous silicon (a-Si:H) are presented. We confirm polarized electroabsorption effect of a-Si:H with the present `sandwich' electrodes, in fact, we find a significantly stronger polarization dependence compared with earlier work based on electroabsorption detected using coplanar electrodes on a-Si:H thin films. We did not reproduce the significant dependence of the polarized electroabsorption upon light soaking, which was found in previous work with coplanar electrodes. We speculate the difference between two electrode geometries is due to the space charge and two dimensional fields.