Surface analyses of nanomachined films are performed using atomic force microscopy. Both surface roughness and fractal dimension are the important factors in all areas of nanotribology and in evaluating the quality of a nanomachining operation. Nanomachining experiments are conducted to investigate the influence of the hardness of a material on the surface properties. Results indicate that the same load causes different depths of groove in the different materials studied (Ta, Pt). Rougher surfaces are produced by larger depths of groove. In addition, the fractal dimension increases as the load increases. © 2005 Elsevier B.V. All rights reserved.