Co-pyrolysjs of DIPSbH and TMIn
Co-pyrolysjs of DIPSbH and TMIn
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DIPSbH 和 TMIn 的共热解
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
R. Gedridge
中科院分区：
文献类型：
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作者：
Y. Chun;G. B. Stringfellow;R. Gedridge
在等温流动管式反应器中，采用质谱分析方法研究了DIPSbH，（C_3H_7）_2SbH单独热解以及DIPSbH与三甲基铟（TMIn，（CH_3）_3In）共热解的反应机理。单独热解DIPSbH的速率限制步骤是还原偶联反应，产生C3H8。另外的产物是C3H6和C6H14，它们分别由DIPSbH热解第二阶段产生的C3H7自由基的反硝化和重组反应产生。DIPSbH与TMIn的混合物在反应器中混合后立即在石英壁上产生非挥发性加合物，即使在室温下也是如此。在室温下没有生成产物。然而，对于在100 ° C和200°C之间的反应器温度，发生烷烃消除反应，产生CH 4。剩余的固体产物假定为[（CH 3）2InSb（C3H 7）2]n（n = 2或3）。对于大于200°C的温度，DIPSbH开始独立地热解。该DIPSbH热解开始的温度显著高于单独DIPSbH开始热解的温度（125°C）。这表明，在共热解过程中，加合物的形成延缓了DIPSbH的热解。显然，在DIPSbH可以独立地热解之前，加合物的解离是必要的。DIPSbH和TMIn在250至375°C之间共热解产生（C3 H7）Sb（CH 3）2和（CH 3）3Sb。也没有发现单独的热解DIPSbH。在低温（≤ 300°C）下也检测到相当大量的C2H6。乙烷可能来自[（CH3）2InSb（C3H7）2]n通过分子内烷烃消除反应。据报道，在300和325°C下使用这些前体通过OMVPE生长的InSb样品的高碳污染水平被推测是由在DIPSbH和TMIn的共热解期间形成（C3H7）Sb（CH3）2引起的，而不是在单独的每种前体的热解期间。
The reaction mechanisms for the pyrolysis of diisopropylantimonyhydride (DIPSbH, (C3H7)2SbH) alone and for the co-pyrolysis of DIPSbH and trimethylindium (TMIn, (CH3)3In) in D2 and H2 ambients have been studied in an isothermal flow-tube, “ersatz” reactor using mass spectrometry to analyze the reaction products. The rate limiting step in the pyrolysis of DIPSbH alone is the reductive coupling reaction, producing C3H8. Additional products are C3H6 and C6H14produced by disproportionation and recombination reactions, respectively, of C3H7 radicals produced during the second stage of DIPSbH pyrolysis. The mixture of DIPSbH with TMIn produces a nonvolatile adduct on the quartz walls immediately after mixing in the reactor even at room temperature. No products were evolved at room temperature. However, for reactor temperatures between 100 and 200°C, an alkane elimination reaction occurs, producing CH4. The remaining solid product is postulated to be [(CH3)2InSb(C3H7)2]n (n = 2 or 3). For temperatures greater than 200°C, the DIPSbH begins to pyrolyze independently. This temperature for the onset of DIPSbH pyrolysis is considerably above the temperature (125°C) at which pyrolysis begins for DIPSbH alone. This suggests that during co-pyrolysis formation of the adduct retards pyrolysis of DIPSbH. Apparently, dissociation of the adduct is necessary before the DIPSbH can pyrolyze independently. Co-pyrolysis of DIPSbH and TMIn between 250 and 375°C produces (C3H7)Sb(CH3)2 and (CH3)3Sb. Neither is found for the pyrolysis of DIPSbH alone. Considerably larger amounts of C2H6 are also detected at low temperatures (≤ 300°C). The ethane may come from the [(CH3)2InSb(C3H7)2]n via an intramolecular alkane elimination reaction. The high carbon contamination levels reported for InSb samples grown by OMVPE using these precursors at 300 and 325°C are postulated to be caused by the formation of (C3H7)Sb(CH3)2 during the co-pyrolysis of DIPSbH and TMIn, but not during the pyrolysis of each precursor alone.