Silicon nitride films are grown by plasma enhanced chemical vapor deposition from tetrakis(dimethylamido)silicon, Si(NMe2)4, and ammonia precursors at substrate temperatures of 200-400 °C. Backscattering spectrometry shows that the films are close to stoichiometric. Depth profiling by Auger electron spectroscopy shows uniform composition and no oxygen or carbon contamination in the bulk. The films are featureless by scanning electron microscopy under 100,000X magnification.

NbCl4(thf)(2) and 4 equiv of LiNPh(2) react to give the homoleptic Nb(TV) compound Nb(NPh(2))(4). The reactions of NbX(4)(thf)(2) (X = Cl, Br) with 2 equiv of lithium bis(trimethylsilyl)amide lead to the Nb(IV) amido halide complexes Nb(N(SiMe(3))(2))(2)X(2), but the reaction of NbCl4(PMe(3))(2) with 2 equiv of LiNH(2,6-C6H3-i-Pr-2) gives the Nb(V) bis(imido) complex Nb(N-2,6-C6H3-i-Pr-2)(2)Cl(PMe(3))(2). A better preparation of the bis(imide) involves reacting [Nb(NEt(2))(2)Cl-3](2) sequentially with 2 equiv of LiNH(2,6-C6H3-i-Pr-2) and PMe(3). Crystal data (Mo K alpha radiation, lambda = 0.71073 Angstrom): Nb(NPh(2))(4), C48H40N4Nb, T = -50 degrees C, a = 10.596(3), b = 11.622(4), c = 16.177(5), alpha = 86.75(2)degrees, beta = 80.63(2)degrees, gamma = 80.33(3)degrees, triclinic, space group , Z = 2; Nb(N(SiMe(3))(2))(2)Br-2, C12H36Br2N2NbSi4, a = 16.802(1) Angstrom, b = 8.7345(6) Angstrom, c = 20.388(2) Angstrom, beta = 121.241(6)degrees, monoclinic, space group C2/c, Z = 4; Nb(N-2,6-C6H3-i-Pr-2)(2)Cl(PMe(3))2, C30H52ClN2NbP2, a = 17.1309(11) Angstrom, b = 9.6722(7) Angstrom, c = 20.7702(15) Angstrom, beta = 95.934(6), monoclinic, space group P2(1)/c, Z = 4.