Summary: Self-assembly of epitaxial monolayers for vacuum wafer bonding
Biqin Huang, and Ian Appelbaum
Department of Electrical and Computer Engineering, University of Delaware, Newark, Delaware 19716
B. C. Walker
Department of Physics, University of Delaware, Newark, Delaware 19716
Received 8 September 2006; accepted 20 October 2006; published online 1 December 2006
Self-assembled epitaxial metal monolayers can be used for heterointegration of mismatched
semiconductors, leading to simultaneously low interfacial resistance and high optical transparency.
Lattice-mismatched wafers of Si 100 and Si 111 were bonded at room temperature in situ after
vacuum deposition of a single atomic layer of Ag. The interfacial resistance was measured to be
and the optical transmission of the interface at 2500 nm is approximately 98%.
Electron confinement in ultrathin Ag layers as a possible contributor to the bonding energy. © 2006
American Institute of Physics. DOI: 10.1063/1.2399358
Three dimensional integration of semiconductor wafers
is an essential step in developing high-efficiency microelec-
and solar cells.2