Plasma-etched micropillars in 4H-SiC were etched in forming gas (4% H₂, 96% N₂) at 1500, 1550, and 1600 °C at 2.4 and 9.4 standard liters per min (slm). At 2.4 slm, oxygen from the aluminum oxide components of the tube furnace oxidized the SiC surface, and the pillars etched isotropically. At 9.4 slm, the pillars etched crystallographically at 1500 and 1550 °C, and sharp 4H-SiC needless with tips as narrow as 15 nm were produced. The lateral etch rates of both 4H- and 6H-SiC were measured with the a-plane etching faster than the m-plane at 1500 and 1550 °C. At 1600 °C, the m-plane and a-plane etch at comparable rates. Due to the difference in etch rates between the m-plane and a-plane, convex surfaces tend to produce facets parallel to the a-plane, while concave surfaces produce facets parallel to the m-plane.

中文翻译：

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使用成型气体对碳化硅进行高温各向同性和各向异性刻蚀

在的4H-SiC的等离子体蚀刻微柱在形成气体（4％H进行蚀刻₂，96％N ₂）在1500、1550和1600°C下以每分钟2.4和9.4标准升（slm）的速度运行。在2.4 slm时，来自管式炉的氧化铝成分的氧气氧化了SiC表面，并且各向同性地腐蚀了柱子。在9.4 slm的情况下，在1500和1550°C的温度下对柱进行了晶体学刻蚀，产生了尖锐的4H-SiC，其尖端宽至15 nm。在1500和1550°C下，通过a面蚀刻比m面蚀刻更快地测量了4H-SiC和6H-SiC的横向蚀刻速率。在1600°C下，m平面和a平面的蚀刻速率相当。由于m平面和a平面之间的蚀刻速率的差异，凸表面倾向于产生平行于a平面的小平面，而凹表面倾向于产生平行于m平面的小平面。