Hostname: page-component-7bb8b95d7b-495rp Total loading time: 0 Render date: 2024-09-11T17:34:26.317Z Has data issue: false hasContentIssue false

Channel Cracking Technique for Toughness Measurement of Brittle Dielectric Thin Films on Silicon Substrates

Published online by Cambridge University Press:  10 February 2011

Qing Ma
Affiliation:
Intel Corporation, Santa Clara, CA 95052
Joseph Xie
Affiliation:
Intel Corporation, Santa Clara, CA 95052
Sam Chao
Affiliation:
Intel Corporation, Santa Clara, CA 95052
Safaa El-Mansy
Affiliation:
Intel Corporation, Santa Clara, CA 95052
Robert Mcfadden
Affiliation:
Intel Corporation, Santa Clara, CA 95052
Harry Fujimoto
Affiliation:
Intel Corporation, Santa Clara, CA 95052
Get access

Abstract

A technique for the measurement of brittle thin film toughness has been developed. It is based on the mechanics of channel cracking in thin films. Dielectric films including CVD silicon oxide and silicon nitride films were studied using this technique. To prevent channel cracks from propagating into silicon substrates, an aluminum layer was deposited prior to the deposition of the dielectric layer. By using a specially made bending fixture, the cracks were observed in situ when the samples were subject to well controlled stresses. It was observed that for each film, a well defined critical film stress level existed, beyond which the crack velocity accelerated very rapidly. The critical film stresses were obtained by superposition of the critical applied stresses and the residual stresses in the films due to deposition and thermal expansion mismatch. It was shown that this technique was highly consistent in critical stress measurement. A simple shear-lag model was used to obtain the film toughness values using the measured critical film stress data.

Type
Research Article
Copyright
Copyright © Materials Research Society 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Hutchinson, J. W. and Suo, Z., “Mixed Mode Cracking in Layered Materials,” Advances in Applied Mechanics, 29, 63191, 1992.10.1016/S0065-2156(08)70164-9Google Scholar
2. Hu, M.S. and Evans, A.G., “The Cracking and Decohesion of Thin Films on Ductile Substrates,” Acta. Met. 37, 917925, 1989.10.1016/0001-6160(89)90018-7Google Scholar
3. Selverian, J.H. and O'Neil, D., “Strength and Toughness Measurement of Thin Brittle Coatings on Substrates,” Thin Solid Films, 235, 1993.Google Scholar
4. Delannay, F. and Warren, P., “On Crack Interaction and Crack Density in Strain-Induced Cracking of Brittle Films on Ductile Substrates,” Acta Metall. Mater., 39, 1991.10.1016/0956-7151(91)90193-5Google Scholar