SURFACE HYDROXYL CONTENT CONTROLS THE THERMOLYSIS STOICHIOMETRY OF A SURFACE-BOUND ORGANOMETALLIC COMPLEX

The thermal decomposition profile for the product of organometallic ch emical vapor deposition (OMCVD) of tetra(tert-butoxy)zirconium on an o xide-modified aluminum surface depends on the initial surface hydroxyl group coverage. Controlled thermolysis of the tri(tert-butoxy)zirconi um species bound to the low hydroxyl group content surface shows nearl y complete degradation to ZrO2 at T > 350 K. In contrast, thermolysis of the tri(tert-butoxy)zirconium species bound to the hydroxyl group-s aturated surface gives a thermally more stable (to >450 K) di(tert-but oxy)zirconium surface complex. Deposition and thermal evolution reacti ons were followed by both reflection-absorption infrared and X-ray pho toelectron spectroscopies.