Temperature-Programmed Desorption Study on the Decomposition Mechanism of Ti(OC_3H_7)_4 on Si(100)

摘要

The decomposition behavior of titanium tetraisopropoxide (TTIP, Ti(OC_3H_7)_4) on Si (100) has been studied using a thermal desorption technique in vacuum. TTIP is dissociated on Si (100) below 350 K so that the silicon surface is covered with iso-propoxy ligand and hydrogen originating from TTIP. The iso-propoxy ligands adsorbed on the silicon surface react with hydrogen to produce isopropanol between 350 K and 650 K, and some of the ligands produce propylene and acetone at 500 K～700 K. Hydrogen exists as monohydride on the silicon surface showing a characteristic desorption peak at 780 K. At higher dosages, TTIP is not completely dissociated and some of the iso-propoxy ligands are still bound to titanium even at 700 K. These intact ligands of TTIP produce acetone/iso-propanol or propylene at 800 K～1000 K by disproportionation among themselves or by the simple decomposition of the C-O bond in the ligands.