Abstract Evolved gas analysis (EGA) mass-spectrometry (MS) is used to characterize the solid state pyrolysis decomposition pathways of air- and moisture-sensitive organometallic compounds. In this study, the single-source GaAs compounds (Et 2 AsGaEt 2 ) 3 ( 1) , ( t -Bu 2 AsGaEt 2 ) 2 ( 2) , and [ t -Bu(H)AsGaEt 2 ] 2 ( 3) were heated in capillary tubes under inert condition and the volatile products were analyzed by MS. In addition, the relative ratios of evolved gases were characterized using gas chromatography (GC), while the solid state pyrolysis products were analyzed by EDS, 1 H NMR and XRD. Pyrolysis of GaAs single-source materials in the solid state reveals chemical information on the stability of the Ga As bond, an observation masked in gas-phase analysis of single-source materials during chemical vapor deposition. Information on Ga As bond stability may be elucidated due to the volatility of the by-products formed during Ga-As precursor pyrolysis. Loss of Ga As bond integrity in materials with alkyl substitution on Ga and As leads to formation of mobile and volatile alkyl diarsine species, as was observed for the pyrolysis of 1. An in-situ method to monitor solid-state pyrolysis by mass spectrometry identified the loss of a tetraalkyl-diarsine as the critical factor that drives formation of sub-stoichiometric GaAs products from single-source precursors. Replacing a single alkyl group on the As atom with a H (precursor 3 ) leads to the loss of an alkane instead of tetraalkyl-diarsine formation. Solid-state pyrolysis precursor 3 results in the formation of polycrystalline GaAs in up to 58% yield with a 52:48 Ga:As stoichiometry.

中文翻译：

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质谱法推动单源前驱体形成化学计量的 GaAs

摘要 逸出气体分析 (EGA) 质谱 (MS) 用于表征对空气和水分敏感的有机金属化合物的固态热解分解途径。在本研究中，单源 GaAs 化合物 (Et 2 AsGaEt 2 ) 3 ( 1) 、( t -Bu 2 AsGaEt 2 ) 2 ( 2) 和 [ t -Bu(H)AsGaEt 2 ] 2 ( 3) 分别为在惰性条件下在毛细管中加热，并通过 MS 分析挥发性产物。此外，逸出气体的相对比例使用气相色谱法 (GC) 进行表征，而固态热解产物则通过 EDS、 1 H NMR 和 XRD 进行分析。固态 GaAs 单源材料的热解揭示了 Ga As 键稳定性的化学信息，这是在化学气相沉积过程中单源材料气相分析中掩盖的观察结果。由于 Ga-As 前体热解过程中形成的副产物的挥发性，可以阐明有关 Ga As 键稳定性的信息。在 Ga 和 As 上具有烷基取代的材料中 Ga As 键完整性的丧失导致形成可移动和挥发性的烷基二胂物质，如对 1 的热解所观察到的那样。 确定了一种通过质谱法监测固态热解的原位方法四烷基二胂的损失是推动从单源前体形成亚化学计量 GaAs 产品的关键因素。用 H（前体 3 ）替换 As 原子上的单个烷基会导致烷烃的损失，而不是四烷基二胂的形成。固态热解前体 3 导致多晶 GaAs 的形成，产率高达 58%，Ga:As 化学计量比为 52:48。