Planar and transverse electrical conductivity of doped a-Si: H

The authors find a different value of electrical conductivity is obtained from the current-voltage characteristics of n-type hydrogenated amorphous silicon films measured either along or across the plane of the films. Undoped and p-type films give the expected agreement between the two contact configurations. Partially compensated doped films behave according to the dominant dopant. They discount the existence of surface band-bending as the origin of these differences in n-type films, and favour an explanation arising from inefficient incorporation of phosphorus donors in the bulk of the films.