Faculty of Physics and CeNIDE, University of Duisburg-Essen, Lotharstraße 1, 47048 Duisburg, Germany.
Nanotechnology. 2011 Jan 28;22(4):045301. doi: 10.1088/0957-4484/22/4/045301. Epub 2010 Dec 15.
We demonstrate the gas-assisted focused-electron-beam (FEB)-induced etching of GaAs with a resolution of 30 nm at room temperature. We use a scanning electron microscope (SEM) in a dual beam focused ion beam together with xenon difluoride (XeF(2)) that can be injected by a needle directly onto the sample surface. We show that the FEB-induced etching with XeF(2) as a precursor gas results in isotropic and smooth etching of GaAs, while the etch rate depends strongly on the beam current and the electron energy. The natural oxide of GaAs at the sample surface inhibits the etching process; hence, oxide removal in combination with chemical surface passivation is necessary as a strategy to enable this high-resolution etching alternative for GaAs.
我们展示了室温下分辨率为 30nm 的气体辅助聚焦电子束（FEB）诱导砷化镓的刻蚀。我们使用扫描电子显微镜（SEM）在双束聚焦离子束中，结合可通过针尖直接注入样品表面的二氟化氙（XeF2）。我们表明，以 XeF2 作为前驱体气体的 FEB 诱导刻蚀导致 GaAs 的各向同性和平滑刻蚀，而刻蚀速率强烈依赖于束流和电子能量。样品表面的 GaAs 自然氧化物会抑制刻蚀过程；因此，为了实现这种 GaAs 的高分辨率刻蚀替代方案，需要进行氧化物去除和化学表面钝化相结合的策略。
