Substrate effects on yield point phenomena in epitaxial thin films

D. E. Kramer, L. C. Chen, C. J. Palmstrom, W. W. Gerberich

Research output: Contribution to journalArticlepeer-review


The yield point phenomenon observed in nanoindentation of metallic single crystals has been attributed to dislocation nucleation. The event is preceded by elastic reversible indentation followed by a rapid increase of indenter tip displacement. A similar event has been seen in epitaxial Co films on GaAs substrates. As these films are on the order of 10 nm thick, the substrate plays a significant role in dislocation behavior as dislocations are emitted at the nucleation site. Epitaxial Fe films 23 and 100 angstroms in thickness have been grown on GaAs and GaAs with a Sc0.3Er0.7As interlayer. Nanoindentation experiments have been performed using the Hysitron Triboscope, an add-on device to an atomic force microscope. The influence of film thickness, epitaxial interlayer, and biaxial misfit stress on the yield point behavior in the overlayer will be considered.

Original languageEnglish (US)
Pages (from-to)89-94
Number of pages6
JournalMaterials Research Society Symposium - Proceedings
StatePublished - Dec 1 1998


Dive into the research topics of 'Substrate effects on yield point phenomena in epitaxial thin films'. Together they form a unique fingerprint.

Cite this