Analysis of Ti-Si-N diffusion barrier films obtained by r.f. magnetron sputtering

Thin films of Ti-Si-N are deposited by r.f. magnetron sputtering in a Ar/N- 2 gas mixture. The magnetron discharge is operated at 10 mTorr with 5 and 1 0% N-2 in the gas mixture and r.f. powers ranging from 100 to 200 W. The co mposition and electrical resistivity of the thin films were determined by e nergy dispersive X-ray spectroscopy and the four-point probe method, respec tively. The structure of the films was determined by high-resolution transm ission electron microscopy. The Ti-Si-N films were either amorphous or cont ained cubic TiN nanosized grains in an amorphous phase. The diffusion barri er properties of 10-nm thick film between Cu and Si were studied from 500 t o 700 degrees C. The highest failure temperature of 650 degrees C was obtai ned for Ti-37.5 Si-27 N-35.5 which. contains 4-nm TiN crystallites in an am orphous phase. (C) 2000 Elsevier Science B.V. All rights reserved.