Effect of B and the Si/C ratio on high-temperature stability of Si-B-C-N materials
Effect of B and the Si/C ratio on high-temperature stability of Si-B-C-N materials
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DOI：
10.1209/epl/i2006-10283-5
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发表时间：
2006-11-01
期刊：
影响因子：
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通讯作者：
McKenzie, D. R.
中科院分区：
文献类型：
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作者：
Houska, J.;Vlcek, J.;McKenzie, D. R.
用反应磁控溅射方法制备了非晶态Si-B-C-N合金，并用实验和分子动力学模拟相结合的方法研究了其高温稳定性。结果表明，较高的Si/C比和B的加入都提高了材料的热稳定性。我们发现，在较高的Si/C比下，同类型键的寿命明显较长。硼的加入导致与氮有关的孤立对中的一些电子转化为成键电子。这增加了网络的平均协调数。在这两种情况下，较高的网络配位数和由此产生的较低的扩散，表现为更长的键寿命，将材料中的分解反应转移到更高的温度。
Amorphous Si-B-C-N alloys were deposited by reactive magnetron sputtering, and their high-temperature stability was investigated using a combined approach of experiment and molecular-dynamics simulations. We show that both a higher Si/C ratio and the addition of boron improve the thermal stability of the materials. We find that lifetimes of bonds of the same type are significantly longer at the higher Si/C ratio. The addition of boron results in a conversion of some of the electrons in lone pairs associated with nitrogen to bonding electrons. This increases the network's average coordination number. In both cases, the higher network coordination number and resulting lower diffusion, expressed in terms of longer bond lifetimes, shift decomposition reactions in materials to higher temperatures.