Compounds of the type [Me2M(OR)]n have been reported in the literature (M = Ga; R = Me,33 CH3, CD3, C2H5,[34] tBu, nBu, Me, PhCH2,35-37
OCy;38 been M =In, R = Me,39 CD3,40 tBu,41 SiMe3 42).
Dimethylgallium methoxide trimer [GaMe2(OMe)]3 (DMGaMO) is potentially applicable as MOCVD precursor.
33. S. Daniele, D. Tcheboukov, L. G. Hubert-Pfalzgraf, J. Mater. Chem., 2002, 12, 2519.
34. G. Mann, H. Olapinski, J. W. R. Ott, Z. Anorg. Allg. Chem., 1974, 410, 195.
35. N. Chikinova, V. Alferov, V. Alyasov, Y. Aleksandrov, N. Vyshin-skii, V. Tsvetkov, Zh. Obsh. Khim., 1989, 59, 1795.
36. Y. Aleksandrov, N. Chikinova, G. I. Makin, V. I. Bregadze, L. M. Golubinskaya, Metallorgan. Khim., 1989, 2, 524.
Dimethylgallium isopropoxide (DMGIP) GaMe2(OiPr), a gallium analogue of dimethylaluminum isopropoxide, is a non-pyrophoric liquid at room temperature with relatively high vapor pressure.
GaMe2(OiPr) has been applied for the growth of thin layers of gallium oxide (Ga2O3), both by ALD and MOCVD. In case of deposition using ALD method (using water was as the oxygen source), DMGIP displayed an ALD temperature window in the range 280–300 °C with a growth rate of ∼0.3 Å per cycle. In case of growth by MOCVD method (using oxygen as the co-reactant) Ga2O3 films were grown in the higher temperature range (450–625°C), with activation energy of 225.5 kJ mol−1. [[i]]
[i] Heeju Lee, Kunhee Kim, Jeong-Jun Woo, Doo-Jin Jun, Youngsoo Park,Yunsoo Kim,Hong Won Lee,Yong Jai Cho, Hyun Mo Cho, Chemical Vapor Deposition, Vol.17, Issue 7-9, p.191–197, September, 2011
http://onlinelibrary.wiley.com/doi/10.1002/cvde.201106879/abstract?deniedAccessCustomisedMessage=&userIsAuthenticated=false , “ALD and MOCVD of Ga2O3 Thin Films Using the New Ga Precursor Dimethylgallium Isopropoxide, Me2GaOiPr”
GaMe2(OC(CF3)2CH2NHBut) for Ga2O3 CVD
GaMe2(OC(CF3)2CH2NHBut) was synthesized by addition to GaMe3 of one equivalent of amino alcohol HL; this afforded complex GaMe2L in high yield with elimination of methane. Variable-temperature 1H NMR studies indicated the occurrence of rapid N→Ga bond scission, followed by recoordination with a change of the absolute configuration. Changing solvent from CDCl3 to more polar media such as deuterated toluene or THF resulted in lower recoordination activation barrier. (Fig.)
GaMe2(OC(CF3)2CH2NHBut) has been tested as precursor for Ga2O3 CVD. The as-deposited films were analyzed using SEM (Fig.), XPS, and RBS.[470]
[see GaCl(OC(CF3)2CH2NMe2)2 section]
Diethylgallium dimethylaminoethoxide GaEt2(dmae)
Diethylgallium 2-methoxymethyl-2-propoxide GaEt2(mmp)
GaEt2(dmae), GaEt2(mmp) for Ga2O3 CVD
Donor-functionalised diethylgallium alkoxides [Et2Ga(OR)]2 (R = CH2CH2NMe2 or C(CH3)2CH2OMe) were synthesized by the 1∶1 reaction of GaEt3 with ROH in hexane or CH2Cl2 at room temperature. TGA was used to study thermal decomposition of these compounds.
Low pressure CVD using [Et2Ga(OCH2CH2NMe2)]2 and [Et2Ga(OC(CH3)2CH2OMe)] as precursors resulted in the formation of thin films of crystalline Ga2O3. [471]
The dimeric gallium mono(alkoxides) [Et2Ga(OR)]2 have been prepared from the reaction of GaEt3 with one equivalent of ROH (R =
CH2CH2NMe2, CH(CH2NMe2)2, CH(CH3)CH2NMe2, C(CH3)2CH2OMe, CH2CH2OMe, CH2CH2OMe and CH(CH3)2) under reflux conditions for 24 hours.The complexes adopt dimeric structures with a planar Ga2O2 ring, with each gallium atom adopting a distorted trigonal bipyramidal geometry with the ethyl groups taking the equatorial positions and the bridging alkoxide group filling the axial position (Fig.2.3).
These gallium mono(alkoxides) [Et2Ga(OR)]2 were applied as precursors to deposit thin layers of gallium oxide. The grown films resulted in oxygen deficient films.