Oxidation of Single‐Crystal Silicon Carbide Part II . Kinetic Model
Oxidation of Single‐Crystal Silicon Carbide Part II . Kinetic Model
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DOI：
10.1149/1.2087080
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发表时间：
1990-09
影响因子：
3.9
通讯作者：
Z. Zheng;R. E. Tressler;K. E. Spear
中科院分区：
文献类型：
--
作者：
Z. Zheng;R. E. Tressler;K. E. Spear
单晶在干氧条件下（10−3‐1 atm, 1200°-1500°C）的氧化遵循抛物线动力学。（0001）碳表面氧化速率的氧分压依赖性随着温度的升高而降低（从1200℃时的0.6降低到1500℃时的0.3）。基于氧化剂通过分子和离子氧扩散机制在氧化物中平行迁移的动力学模型符合观察到的氧化行为。利用实验数据推导出的氧化剂通过氧化物的扩散率和活化能值与分子氧通过玻璃体的扩散率和活化能值相似。当氧化在较高的温度和较低的氧分压下发生时，离子氧通过晶格向内扩散（可能是通过空位机制）变得更加重要。用实验数据推导出的离子氧化剂扩散的扩散率和活化能值与文献中报道的氧通过二氧化硅扩散的值相似。
The oxidation of single‐crystal in dry oxygen (10−3‐1 atm and 1200°–1500°C) followed parabolic kinetics. The oxygen partial pressure dependence of the oxidation rate of the (0001) carbon face decreased with increasing temperature (from 0.6 at 1200°C to 0.3 at 1500°C). A kinetic model based on parallel transport of oxidants through the oxide via molecular and ionic oxygen diffusion mechanisms fits the observed oxidation behavior. Both diffusivity and activation energy values for oxidants permeating through the oxide derived from the model using the experimental data are similar to those for molecular oxygen permeating through vitreous . Ionic oxygen diffusion inward via the lattice presumably via a vacancy mechanism becomes more important when oxidation takes place at higher temperatures and at low oxygen partial pressures. Both diffusivity and activation energy values for the ionic oxidant diffusion derived from the model using the experimental data are similar to those values for the diffusion of oxygen through silica reported in the literature.