title: Control of Alq3 wetting layer thickness via substrate surface functionalization.
abstract: The effects of substrate surface energy and vapor deposition rate on the initial growth of porous columnar tris(8-hydroxyquinoline)aluminum (Alq3) nanostructures were investigated. Alq3 nanostructures thermally evaporated onto as-supplied Si substrates bearing an oxide were observed to form a solid wetting layer, likely caused by an interfacial energy mismatch between the substrate and Alq3. Wetting layer thickness control is important for potential optoelectronic applications. A dramatic decrease in wetting layer thickness was achieved by depositing Alq3 onto alkyltrichlorosilane-derivatized Si/oxide substrates. Similar effects were noted with increasing deposition rates. These two effects enable tailoring of the wetting layer thickness.
authors.affiliation: Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta, Canada. stsoi@ece.ualberta.ca
authors.forename: Shufen
authors.initials: S
authors.lastname: Tsoi
authors.forename: Bryan
authors.initials: B
authors.lastname: Szeto
authors.forename: Michael D
authors.initials: MD
authors.lastname: Fleischauer
authors.forename: Jonathan G C
authors.initials: JG
authors.lastname: Veinot
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Brett