A possibility of deposition from laser-induced plasma is investigated in search for an economic and simple method for obtaining isotopic compounds from enriched gaseous precursors although no isotopic compounds are used in this the proof-of-principle work. A breakdown in mixtures of BCl3 and BCl3 with hydrogen, argon, and methane are studied both theoretically and experimentally. Equilibrium chemistry calculations show the deposition of boron, boron carbide, and carbon is thermodynamically favorable in BCl3 systems and only carbon in BF3 systems. Dynamic calculation of expanding plasma is performed using fluid dynamics coupled with equilibrium chemistry. Condensed phases of boron, boron carbide, and graphite are predicted with maximum concentrations in peripheral zones of the plasma. In experiment, plasma is induced in mixtures BCl3, H2 + BCl3, H2 + Ar + BCl3, H2 + BCl3 + CH4, BF3, H2 + BF3, H2 + Ar + BF3, and H2 + Ar + BF3. The gases are analyzed before, during, and after laser irradiation by optical and mass spectrometry methods. The results show the composition of reaction products close to that predicted theoretically. The conversion of precursor gases BCl3 and BF3 into gaseous and condensed products is 100% for BCl3 and 80% for BF3. Solid deposits of up to 30 mg are obtained from all reaction mixtures. Due to technical reasons only FTIR characterization of the BCl3 + H2 + CH4 deposit is done. It points to presence of condensed boron and boron carbide predicted by the model. Overall, the calculations and preliminary experimental results imply the chemical vapor deposition with laser induced plasma is promising for conversion of gaseous enriched precursors into elemental isotopes and their isotopic compounds.

中文翻译：

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通过对挥发性卤化硼 BCl3 和 BF3 进行氢还原，用于化学气相沉积的激光诱导介电击穿

研究了从激光诱导等离子体沉积的可能性，以寻找一种经济且简单的方法来从富集的气态前体中获得同位素化合物，尽管在原理验证工作中没有使用同位素化合物。从理论上和实验上研究了 BCl3 和 BCl3 与氢气、氩气和甲烷的混合物的分解。平衡化学计算表明硼、碳化硼和碳的沉积在 BCl3 系统中在热力学上是有利的，而在 BF3 系统中只有碳的沉积。膨胀等离子体的动态计算是使用流体动力学与平衡化学相结合来进行的。硼、碳化硼和石墨的凝聚相预计在等离子体的外围区域具有最大浓度。在实验中，等离子体在 BCl3、H2 + BCl3、H2 + Ar + BCl3、H2 + BCl3 + CH4、BF3、H2 + BF3、H2 + Ar + BF3 和 H2 + Ar + BF3。在激光照射之前、期间和之后，通过光学和质谱法对气体进行分析。结果表明反应产物的组成与理论预测接近。前体气体 BCl3 和 BF3 向气态和冷凝产物的转化率对于 BCl3 为 100%，对于 BF3 为 80%。从所有反应混合物中获得高达 30mg 的固体沉积物。由于技术原因，仅对 BCl3 + H2 + CH4 沉积物进行了 FTIR 表征。它指出模型预测的凝聚硼和碳化硼的存在。全面的，