Influence of substrate bias voltage on the in situ stress measured by an improved optical cantilever technique of sputtered chromium films

This paper reports on the effect of substrate bias voltage on chromium thin film deposition during DC magnetron sputtering. During the process, this effect can modify the texture and intrinsic stress of the coatings. This specific property can be determined by an original in situ method: the optical cantilever technique. The layer characteristics depend on the bombardment effect caused by the substrate bias voltage, which has two consequences: (i) for lower substrate bias voltages (V-s), the coatings are dense, the grain size is fine, and films possess an intrinsic compressive stress; and (ii) for higher V-s, a recrystallisation induces an increase in the grain size and an intrinsic tensile stress. Moreover, the preferred growth orientation and the film roughness are discussed in relation to the substrate bias voltage. (C) 2001 Published by Elsevier Science B.V. All rights reserved.