Ga—N Bonds

Other compounds containing Al-N or Ga-N bonds, including heterocyclic compounds and cluster organometallic compounds, are considered in section 7.3.6. 

There have been many other reports of single-source azido precursors, all aimed at achieving device-quality films using moderate deposition conditions. The azide precursors have the advantages of (i) having preformed Ga—N bonds and (ii) only a limited number of the undesirable Ga—C and N—C bonds which can lead to carbon incorporation into the nitride films.311 A list of azido-based precursors and deposition conditions is given in Table 14. 

Most gallium amides are dimers which feature a planar (GaN)2 core with Ga—N bond lengths in the range 1.96-2.10 A. As is the case for the monomers many of these... 

TripNs to yield, along with N2 formation, the first monomeric A1 and Ga imide complexes HC(CMeNAr)2 M N(Trip) with M = A1 and Ga, respectively. In the case of the Ga imide complex (9), experimental data and theoretical calcnlations snpport a mnltiple bond character for the exocychc Ga N bond. 

Examination of the geometrical parameters in Table 2 shows that the Ga-N bonds are only slightly longer than Al-N and that the Ga-H bonds have similar distances to the Al-H bonds. The use of an RECP made little difference, except that the MP2/CEP-121G Ga-H distance was consistently —0.03 A shorter than MP2/6-31G and a similar trend of —0.01 shorter Ga-N distances with the RECP. The Al-N and Ga-N bond distances compare favorably with the shortest experimental monoamide values (1.784 and 1.847 A, respectively (17). Pink et al. also used the Hay-Wadt effective core potential (21) to optimize H2GaNH2, getting 1.794 A for the Ga-N distance (17). This is 0.02 A shorter than with the CEP-121G basis. 

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