SPECTROSCOPIC AND STRUCTURAL STUDIES ON VOLATILE GALLIUM BETA-DIKETONATES AS POTENTIAL PRECURSORS FOR MOCVD

The complexes Ga(hfac), (Hhfac = hexafluoroacetylacetone) and Ga(dpm)3 (Hdpm = dipivaloylmethane) have been studied by solid and gas phase IR, mass spectrometry, H-1 and C-13 NMR, in order to prove their suitability as precursors for Ga2O3 deposition via metalorganic chemical vapor deposition (MOCVD). The crystal structure of Ga(hfac)3 was also deter-mined. The complex crystallizes in the monoclinic space group P2(1)/n with a = 9.034(3), b=13.399(3), c=19.100(4) angstrom, beta=92.19(3)-degrees for Z=4. The final R factor was 0.048. The Ga(III) ion exhibits a regular octahedral coordination with Ga-0 bond distance of 1.954(5) angstrom (av. value). The X-ray, IR and MS studies showed the presence of identical monomeric species both in the solid and in the gas phase. Ga(hfac)3 was used in preliminary MOCVD experiments to grow Ga2O3 films.