Junction capacitance measurements of tetrahedrally bonded amorphous-C/crystalline-Si heterostructures were used to deduce the defect density in the thin C films. By using the drive level capacitance profiling technique, an homogeneous defect density of 6 x 1017/cm3 was found in undoped (p-type) C films. It was an order of magnitude higher in N-doped films. Admittance measurements revealed defect states at the C/Si interface, with a density that exceeded 2 x 1012/cm2.

Defect Densities in Tetrahedrally Bonded Amorphous Carbon Deduced by Junction Capacitance Techniques. K.C.Palinginis, Y.Lubianiker, J.D.Cohen, A.Ilie, B.Kleinsorge, W.I.Milne: Applied Physics Letters, 1999, 74[3], 371-3