High resolution transmission electron microscopy of metallic film/laser-irradiated alumina couples

A. J. Pedraza, Siqi Cao, L. F. Allard, D. H. Lowndes

Research output: Contribution to journalConference articlepeer-review

3 Scopus citations

Abstract

A near-surface thin layer is melted when single crystal alumina (sapphire) is pulsed laser-irradiated in an Ar-4%H2 atmosphere. γ-alumina grows epitaxially from the (0001) face of α-alumina (sapphire) during the rapid solidification of this layer that occurs once the laser pulse is over. Cross sectional high resolution transmission electron microscopy (HRTEM) reveals that the interface between unmelted sapphire and γ-alumina is atomistically flat with steps of one to a few close-packed oxygen layers; however, pronounced lattice distortions exist in the resolidified γ-alumina. HRTEM also is used to study the metal-ceramic interface of a copper film deposited on a laser-irradiated alumina substrate. The observed changes of the interfacial structure relative to that of unexposed substrates are correlated with the strong enhancement of film-substrate bonding promoted by laser irradiation. HRTEM shows that a thin amorphous film is produced after irradiation of 99.6% polycrystalline alumina. Formation of a diffuse interface and atomic rearrangements that can take place in metastable phases contribute to enhance the bonding strength of copper to laser-irradiated alumina.

Original languageEnglish
Pages (from-to)53-58
Number of pages6
JournalMaterials Research Society Symposium - Proceedings
Volume357
StatePublished - 1995
Externally publishedYes
EventProceedings of the 1994 MRS Fall Meeting - Boston, MA, USA
Duration: Nov 28 1994Nov 30 1994

Fingerprint

Dive into the research topics of 'High resolution transmission electron microscopy of metallic film/laser-irradiated alumina couples'. Together they form a unique fingerprint.

Cite this