Stacking fault energy of 6H-SiC and 4H-SiC single crystals
Stacking fault energy of 6H-SiC and 4H-SiC single crystals
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DOI：
10.1080/01418610008212090
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发表时间：
2000-04-01
期刊：
影响因子：
--
通讯作者：
Pirouz, P
中科院分区：
文献类型：
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作者：
Hong, MH;Samant, AV;Pirouz, P
SiC的单晶4 H和6 H多型体在1300 ℃的压缩下变形。所有的形变诱导位错被发现被解离成两个局部边界的本征层错带。利用透射电子显微镜的双束明场和弱束暗场技术，从分离位错的两个部分的分离宽度确定了这两种SiC多型体的层错能。测得4 H-SiC的层错能为14.7 ± 2.5mJ·m（-2），6 H-SiC的层错能为2.9 ± 0.6mJ·m（-2）。作为验证，还从扩展结点的最小曲率半径确定了4 H-SiC的层错能。后一种方法给出的值为12.2 +/- 1.1 mJ m（-2），该值在通过测量部分位错分离确定的范围内。4 H-和6 H-SiC的层错能的实验值进行了比较从广义轴向次近邻伊辛（ANNNI）自旋模型获得的估计。结果表明，理论模型预测的6 H-SiC层错能比4 H-SiC层错能低，预测值分别在实验值的5%和40%以内。
Single crystal 4H and 6H polytypes of SIC have been deformed in compression at 1300 degrees C. All the deformation-induced dislocations were found to be dissociated into two partials bounding a ribbon of intrinsic stacking fault. Using two-beam bright-field and weak-beam dark-field techniques of transmission electron microscopy, the stacking fault energy of these two SiC polytypes has been determined from the separation width of the two partials of dissociated dislocations. The stacking fault energy of 4H-SiC is determined to be 14.7 +/- 2.5 mJ m(-2), and that of 6H-SiC to be 2.9 +/- 0.6 mJ m(-2). As a verification, the stacking fault energy of 4H-SiC has been determined also from the minimum radius of curvature of extended nodes. This latter method gave a value of 12.2 +/- 1.1 mJ m(-2) which is within the range determined from measurement of partial dislocation separations. The experimental values of stacking fault energy for 4H- and 6H-SiC have been compared with estimates obtained from a generalized axial next-nearest-neighbour Ising (ANNNI) spin model. It is found that the theoretical models predict the lower stacking fault energy of 6H-SiC compared with that of 4H-SiC, and the predicted energies are, respectively, within 5% and 40% of the experimental values.