LOW-TEMPERATURE CHEMICAL VAPOR DEPOSITION OF SILVER ON AG(111) USING ((CH3)(3)CCOCHCOC3F7)AGPET(3)

摘要

The adsorption of 1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4, (fodH) and (1,1,1,2,2,3,3-heptafluoro-7,7-dimethyl-4,6-octanedionato)(triethylphosphi ne)silver(I) ((fod)AgPEt(3)) on Ag(III) has been studied using reflection absorption infrared spectroscopy and temperature programmed desorption techniques. fodH adsorbs molecularly in two adsorbed states. The first state adsorbs with its molecular plane parallel to the surface and desorbs at 250 g. The second adsorbed state is the condensed phase which desorbs at 197 K. The most interesting result of this work is that, at the lowest coverages, the first (fod)AgPEt(3) molecules adsorb parallel to the Ag(III) surface and dissociate at very low temperature. For higher doses, (fod)AgPEt(3) molecules are randomly oriented at low temperature. Upon heating of the sample, these molecules reorient their molecular plane to a position nearly perpendicular to the Ag(III) surface before their desorption at 290 K. The desorbing byproducts resulting from the dissociation of the flat-laying molecules are fodH at 200 K, CH4 at 140 K, and PEt(3) at 135 and 170 K. At high temperature the desorption of HF was observed at 490 K and CO2 around 600 K. The desorption of C3F7 and C4H9 radicals was also detected at this temperature. [References: 43]