MOCVD of MgAl2O4 thin films using new single molecular precursors: application of beta-hydrogen elimination to the growth of heterometallic oxide films

We have deposited the MgAl2O4 thin films on Si(1 0 0) substrates in the tem perature range of 270 similar to 600 degreesC using newly developed single molecular precursors of Mg[(mu -O'Bu)(2)AlMe2](2) and Mg[Al(O'Bu)(4)](2) by MOCVD. Polycrystalline, crack-free stoichiometric MgAl2O4 thin films were successfully grown on at as low as 400 degreesC. This growth temperature wa s much lower than that of conventional CVD, and this is the first report of the MgAl2O3 growth using Mg[(mu -O'Bu)(2)AlMe2](2). During film deposition , the vapor pressure of Mg[Al(O'Bu)(4)](2) was decreased due to oligomeriza tion of the precursor itself. When Mg[(mu O'Bu)(2)AlMe2](2) was used, howev er, the vapor transport problem of the precursor was solved by introducing more volatile alkyl group. beta -Hydrogen elimination was employed in the g rowth mechanism. The synthesized precursors and the as-grown films were cha racterized with NMR, XRD, XPS, RES, and SEM, and the gas-phase by-products of the CVD reaction were collected and identified by gas chromatography. (C ) 2001 Elsevier Science B.V. All rights reserved.