Local electronic transport in microcrystalline silicon observed by combined atomic force microscopy

Atomic force microscope with conductive cantilever was used to map local conductance of the microcrystalline silicon at different stages of growth. Evolution of the surface roughness, grains, and conductive regions was measured for layer thicknesses from 10 to 4700 nm. Nucleation density and the growth depends on the material of the bottom electrode. Contrast mechanism in the local current maps is discussed in relationship to local I(V) properties. Inhomogeneous spatial distribution of the current has direct consequences for the solar cells.