Gallium tris(dimethylamide) dimer Ga2(NMe2)6
Ga2(NMe2)6 (with NH3 as co-reactant) has been applied as precursor for the growth of GaN films by MOCVD at substrate temperatures of >200°C [4]
Gallium tris(dimethylamide) dimer [Ga(NMe2)3]2 , in combination with alkylamino- and alkoxyalcohols ROH as oxygen source (R = CH2CH2NMe2, CH(CH2NMe2)2, CH(CH3)CH2NMe2, CH2CH2OMe or C(CH3)2CH2OMe), have been applied for the preparation of thin films of Ga2O3 by aerosol assisted chemical vapour deposition (AACVD) on glass substrates using toluene as solvent for the precursors. Transparent, unreflective films, X-Ray amorphous Ga2O3 films were obtained at 550°C, they were characterised by SEM, WDX, XPS and Raman spectroscopy Gas-sensing experiments indicated n-type response of the films to ethanol at various temperatures. [[i] ]
[i] S. Basharat, Claire J. Carmalt, Russell Binions, Robert Palgrave and Ivan P. Parkin, Dalton Trans., 2008, 591-595 , “Gallium oxide thin films from the AACVD of [Ga(NMe2)3]2 and donor functionalised alcohols”
Ga dialkylamide Ga2(NMe2)6 and Gallium diketonate have been compared in the two precursor systems: Ga2(NMe2)6/ Er(C5H4Me)3/ H2O and Ga(acac)3 / Er(thd)3 / O3 were compared for ALD growth of ErxGa2-xO3 (0 ≤ x ≤ 2) thin films. Ga alkylamide/erbium cyclopentadienyl system allowed to grow films at lower substrate temperature (250°C) than diketonate system (350°C). Both processes exhibited surface-limited ALD growth and prodused uniform films. The value of x in ErxGa2-xO3 was easily varied by selecting a pulse sequence with an appropriate Er/Ga precursor ratio. Er-Ga diketonate/O3 system produced purer films except fluorine impurity (C, H, N <0.2-0.3at.%, F 0,6-2.2at.%) than Ga amide/ Er cyclopentadienyl/ H2O system (C 2.0–6.1%, H 5.0–10.3%, N 0.3–0.7%, and 0.1at% F) by RBS and TOF-ERDA. The film growth rate with diketonate system was 0.25-0.28Å/cycle, while that with amide/cyclopentadienyl was much higher - 1.0 -1.5 Å/cycle. The effective permittivity of representative samples was essentially the same: 10 - 11.3 for diketonates/O3 system and 9.2 - 10.4 for the amide/cyclopentadienyl/H2O. As-deposited films of both precursor systems were amorphous, but crystallized either to Er3Ga5O12 or to a mixture of β-Ga2O3 and Er3Ga5O12 upon annealing at 900-1000 °C under N2 atmosphere. Atomic force microscopy showed root mean square Film rms surface roughnesses of <1.0 nm regardless of precursor system or film composition was determined by AFM [469]