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The cracking resistance of nanoscale layers and films

Published online by Cambridge University Press:  03 March 2011

D.K. Leung
Affiliation:
Materials Department, College of Engineering, University of California, Santa Barbara, Santa Barbara, California 93106-5050
M.Y. He
Affiliation:
Materials Department, College of Engineering, University of California, Santa Barbara, Santa Barbara, California 93106-5050
A.G. Evans
Affiliation:
Materials Department, College of Engineering, University of California, Santa Barbara, Santa Barbara, California 93106-5050
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Abstract

Thin film cracking has been studied for a nanometer brittle/ductile layered system consisting of Si and Cu. Single Si films and Cu/Si/Cu trilayers were fabricated by physical vapor deposition. The films were deposited onto a ductile substrate consisting of stainless steel with a thin polyimide interlayer. Straining of the substrate induced cracking of the Si. Cracking strains ≥1% were observed, particularly in layers ≤100 nm thick. The critical cracking strain was found to depend upon the Si layer thickness, as well as the thickness and elastic/plastic properties of the adjacent ductile layers. Si cracking was suppressed by the presence of adjacent Cu layers. The measured strains were compared with lower-bound critical strains for tunnel and channel cracking. Comparisons indicated that these mechanisms control the critical strain found in trilayers, because trilayer fabrication introduces edge flaws larger than the Si layer thickness. Conversely, for Si films, the measured critical strains exceed the channel cracking strain, because the flaws in these films are relatively small.

Type
Articles
Copyright
Copyright © Materials Research Society 1995

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References

REFERENCES

1Heredia, F. E., He, M. Y., Lucas, G. E., Evans, A. G., Dève, H.E., and Konitzer, D., Acta Metall. Mater. 41(2), 505511 (1993).CrossRefGoogle Scholar
2Cao, H. C., Löfvander, J.P.A., Evans, A. G., and Rowe, R.G., Mater. Sci. Eng. A (1995, in press).Google Scholar
3Cheng, Z. and Mecholsky, J. J. Jr., J. Am. Ceram. Soc. 76(5), 12581264 (1993).CrossRefGoogle Scholar
4Calvert, P., MRS Bull. XVII (10), 3740 (1992).CrossRefGoogle Scholar
5Cao, H. C. and Evans, A. G., Acta Metall. Mater. 39(12), 29973005 (1991).CrossRefGoogle Scholar
6Odette, G. R., Chao, B. L., Scheckherd, J. W., and Lucas, G. E., Acta Metall. Mater. 40(9), 23812389 (1992).CrossRefGoogle Scholar
7He, M. Y., Heredia, F. E., Wissuchek, D. J., Shaw, M. C., and Evans, A.G., Acta Metall. Mater. 41(4), 12231229 (1993).CrossRefGoogle Scholar
8Shaw, M. C., Marshall, D. B., Dadkhah, M. S., and Evans, A.G., Acta Metall. Mater. 41(11), 33113322 (1993).CrossRefGoogle Scholar
9Ho, S. and Suo, Z., J. Appl. Mech. 60(4), 890894 (1993).CrossRefGoogle Scholar
10Hutchinson, J. W. and Suo, Z., Adv. Appl. Mech. 29, 63191 (1992).CrossRefGoogle Scholar
11Evans, A. G. and Hutchinson, J. W., Acta Metall. Mater. (1995, in press).Google Scholar
12Hoffman, R. W., Physics of Thin Films (Academic Press Inc., New York, 1966), Vol. 3, p. 211.Google Scholar
13Merz, M. D. and Dahlgren, S. D., J. Appl. Phys. 46(8), 32353237 (1975).CrossRefGoogle Scholar
14Campbell, D. S., Handbook of Thin Film Technology, edited by Maissel, L.I. and Glang, R. (McGraw-Hill, New York, 1970), Chap. 12.Google Scholar
15Thomas, M. E., Hartnett, M. P., and McKay, J. E., J. Vac. Sci. Technol. A 6(4), 25702571 (1988).CrossRefGoogle Scholar
16Leung, D. K., Zhang, N. T., McMeeking, R.M., and Evans, A.G., J. Mater. Res. 10, (1995, in press).Google Scholar
17Chan, K. S., He, M. Y., and Hutchinson, J.W., Mater. Sci. Eng. A 167 (12), 5764 (1993).CrossRefGoogle Scholar
18Tada, H., Paris, P. C., and Irwin, G. R., The Stress Analysis of Cracks Handbook (Del Research Corporation, 1973).Google Scholar