Selective Dry Etching of Germanium with Respect to Silicon and Vice Versa
Selective Dry Etching of Germanium with Respect to Silicon and Vice Versa
复制标题
相对于硅选择性干蚀刻锗，反之亦然
DOI：
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发表时间：
1991
期刊：
影响因子：
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通讯作者：
J. Lindström
中科院分区：
文献类型：
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作者：
G. Oehrlein;T. Bestwick;P. Jones;M. Jaso;J. Lindström
它表明，锗比硅更快地蚀刻在传统的氟，氯，溴基低压等离子体和高Ge/Si蚀刻速率比ERR可以很容易地获得。由等离子体产生的氟原子引起的Ge的蚀刻比Si的蚀刻更少地依赖于离子轰击。因此，对于等离子体蚀刻条件或对于在高压（250 m3）下的反应离子蚀刻，可以实现非常高的Ge/Si ERR（40），其中离子轰击效应对蚀刻的重要性降低。对于低压下的反应离子蚀刻，其中蚀刻是强烈离子增强的，Ge/Si蚀刻速率比降低到3。硅在混合气体中的腐蚀速度可能比锗快。在这项工作中证明了Si/Ge蚀刻速率比大于70。在Ge表面上形成碳质材料和不挥发的锗-硫化物化合物对于减少氟与衬底的反应和降低Ge蚀刻速率都是重要的。它还表明，这种RIE方法可以用于选择性地蚀刻硅合金。
It is shown that germanium is more rapidly etched than silicon in conventional fluorine‐, chlorine‐, and bromine‐based low‐pressure plasmas and that a high Ge/Si etch rate ratio ERR can be readily obtained. The etching of Ge induced by plasma‐generated fluorine atoms relies much less on ion bombardment than the etching of Si. A very high Ge/Si ERR (40) may therefore be achieved for plasma etching conditions or for reactive ion etching at high pressure (250 mtorr) where the importance of ion bombardment effects on the etching is reduced. For reactive ion etching at low pressure where the etching is strongly ion‐enhanced, the Ge/Si etch rate ratio is reduced to 3. Silicon may be more rapidly etched than Ge in a gas mixture of . A Si/Ge etch rate ratio greater than 70 is demonstrated in this work. Both the formation of carbonaceous material and an involatile germanium‐sulfide compound on the Ge surface are important in reducing the reaction of fluorine with the substrate and lowering the Ge etch rate. It is also shown that this RIE approach may be used to selectively etch Si over a alloy.