Micro-scratch test study of TiN films grown on silicon by chemical vapor deposition

TiN thin films (0.095 mum) were deposited on silicon wafers at 800 degreesC by rapid thermal low-pressure chemical vapor deposition from a TiCl4 + NH3 + H-2 gaseous mixture. Micro-scratches were performed using a system equip ped with an optical microscope, an acoustic emission sensor and a friction force sensor. Critical loads were determined to evaluate the adhesion of Ti N to the substrate. The influence of the indenter state on the critical loa d was studied. Scanning electron micrographs, electron probe microanalyses and chemical etching of the film were performed to identify and interpret t he damage mechanisms. Experimental results were analyzed using the Weibull statistic. It was shown that small particles of TiN were chipped off and fo rmed a third body, which modified the indenter-him contact and contributed to an increase in the range of the critical load. Models previously propose d in the literature, which allow calculation of the work of adhesion from a critical load, are discussed with respect to the damage mechanisms observe d. (C) 2001 Elsevier Science B.V. All rights reserved.