Stress reduction of chromium thin films deposited by cluster-type sputtering system for ultra-large-size (550×650 mm) substrates

• Published in: Vacuum 1998-12, Vol.51 (4), p.761-764
• Main Authors: Nakajima, Katsunori, Onisawa, Ken-ichi, Chahara, Ken-ichi, Minemura, Tetsuroh, Kamei, Mitsuhiro, Setoyama, Eiji
• Format: Article
• Language: English
• ISSN: 0042-207X; 1879-2715
• DOI: 10.1016/S0042-207X(98)00286-3

In order to reduce the intrinsic tensile stress in sputtered Cr films, the relationship between sputtering condition and the stress properties was investigated. By using a laboratory-scale planar dc magnetron sputtering apparatus, it was shown that the tensile stress in the films were decreased with increasing substrate temperature, increasing dc power and decreasing gas pressure. However, it was still as high as 1000 MPa, even when the optimized process condition was applied to a cluster-type sputtering apparatus for ultra-large-size (550×650 mm) substrates. By changing the sputtering gas from Ar to Ne with the cluster-type apparatus, the stress was considerably decreased to the value of approximately 100 MPa. Stress reduction mechanism was discussed in the light of atomic peening effects; the energy of the impinging species at the substrate surface is enhanced in the case of Ne.