Abstract U-shaped diamond trenches with vertical {111} sidewalls for power devices were successfully obtained by anisotropic etching of diamond (110) surfaces using Ni films in high-temperature (1000 °C) water vapor. The etching rate for the diamond (110) surfaces was estimated to be 3.8 μm/min on the basis of the relationship between etching time and etching depth of diamond trenches with (110) bottoms. These (110) bottoms gradually disappeared as the etching progressed. Finally, they completely vanished and each diamond trench was surrounded by four vertical {111} sidewalls and two slanted {111} sidewalls. The formation mechanisms of the U-shaped diamond trenches are also discussed on the basis of the experimental results.

中文翻译：

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通过金刚石 (110) 表面的各向异性蚀刻形成具有垂直 {111} 侧壁的 U 形金刚石沟槽

摘要 通过在高温 (1000 °C) 水蒸气中使用 Ni 薄膜对金刚石 (110) 表面进行各向异性蚀刻，成功获得了用于功率器件的具有垂直 {111} 侧壁的 U 形金刚石沟槽。根据蚀刻时间与具有 (110) 底部的金刚石沟槽的蚀刻深度之间的关系，估计金刚石 (110) 表面的蚀刻速率为 3.8 μm/min。随着蚀刻的进行，这些（110）底部逐渐消失。最后，它们完全消失了，每个金刚石沟槽都被四个垂直的 {111} 侧壁和两个倾斜的 {111} 侧壁包围。在实验结果的基础上还讨论了U形金刚石沟槽的形成机制。