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    MN (M = Al, Ga) 박막제조용 hydrazido- 와 azido- 단일 선구물질의 합성, 특성화 및 박막성장에 관한 연구

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    학위논문(박사) - 한국과학기술원 : 화학과, 2000.2, [ v, 61 p. ]Reaction of MMe3MMe_3 (M = Al, Ga) with 1 equiv of NH2NPh2NH_2NPh_2 affords a dimeric complex [Me2MμN(H)NPh2]2[Me_2M-μ-N(H)NPh_2]_2 [M = Al (1), M = Ga (2)] as a mixture of trans and cis isomers. Purification of 1 and 2 by recrystallization gives only trans isomers 1a and 2a, respectively. Variable-temperature 1H^1H NMR studies reveal that both 1 and 2 in solution undergo trans → cis isomerization with free energy of activation (ΔGc++)(ΔG_c^{++}) values of 15.9 kcal/mol for 1 and 18.3 kcal/mol for 2. The solid state structures of trans isomers 1a and 2a have been determined by single-crystal X-ray diffraction studies. The molecular geometries of 1a and 2a consist of a centrosymmetric and dimeric unit (MN)2(M-N)_2 with two bridging hydrazido groups and two terminal methyl groups bound to each metal atom. The two NNPh2N-NPh_2 groups are trans to each other with respect to the (MN)2(M-N)_2 core plane. The coordination geometry of both metal and nitrogen atoms are distorted tetrahedral. Reaction of trimeric amidogallane, [Et2GaμNH2]3[Et_2Ga-μ-NH_2]_3 with 1 equiv of hydrogen azide affords a dialkylazidogallium-ammonia adduct Et2(N3)Ga:NH3Et_2(N_3)Ga:NH_3 (3). Gallium nitride (GaN) film growth has been carried out in a cold wall organometallic chemical vapor deposition (OMCVD) reactor. The crystalline structure, chemical composition, and optical property of the deposited films have been investigated by X-ray diffraction (XRD), pole figure analysis, scanning electron microscopy (SEM), photoluminescence (PL), transmittance electron microscopy (TEM), and Rutherford backscattering spectrometry (RBS). GaN thin films are grown with 3 on Si(111) substrates in the temperature range of 350~450^℃ in the absence of carrier gas by low-pressure chemical vapor deposition. Hexagonal GaN thin films have been obtained on Si (111) substrates at 350℃ and 6.0×1066.0×10^{-6} Torr . The stoichiometry of the resulting film has been determined by RBS. The film structure has been examined by XRD, pole figure analysis, SEM, and TEM. XRD, pole figure, ...한국과학기술원 : 화학과
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