A nanoindentation study of copper films on oxidised silicon substrates

The indentation hardness of copper films deposited on oxidised silicon substrates is investigated by two methods. The first uses the Oliver and Pharr method for analysing the load–displacement curves and the second involves the measurement of the residual indent impression with AFM. Material pile-up was found at the indent edges, and this area needs to be accounted for in hardness measurement. The effect of the pile-up area is investigated and the ‘true’ film hardness is determined.