Kim, Tae Kyoung Bae, Jee Hwan Kim, Juyoung Cho, Min Kyung Kim, Yu-Chan Jin, Sungho Chun, Dongwon 2024-01-19T17:02:04Z 2024-01-19T17:02:04Z 2021-09-02 2020-08 2072-666X https://pubs.kist.re.kr/handle/201004/118316 Metal-assisted chemical etching (MACE) is widely used to fabricate micro-/nano-structured Si owing to its simplicity and cost-effectiveness. The technique of magnetically guided MACE, involving MACE with a tri-layer metal catalyst, was developed to improve etching speed as well as to adjust the etching direction using an external magnetic field. However, the controllability of the etching direction diminishes with an increase in the etching dimension, owing to the corrosion of Fe due to the etching solution; this impedes the wider application of this approach for the fabrication of complex micro Si structures. In this study, we modified a tri-layer metal catalyst (Au/Fe/Au), wherein the Fe layer was encapsulated to improve direction controllability; this improved controllability was achieved by protecting Fe against the corrosion caused by the etching solution. We demonstrated curved Si microgroove arrays via magnetically guided MACE with Fe encapsulated in the tri-layer catalyst. Furthermore, the curvature in the curved Si microarrays could be modulated via an external magnetic field, indicating that direction controllability could be maintained even for the magnetically guided MACE of bulk Si. The proposed fabrication method developed for producing curved Si microgroove arrays can be applied to electronic devices and micro-electromechanical systems. English MDPI Curved Structure of Si by Improving Etching Direction Controllability in Magnetically Guided Metal-Assisted Chemical Etching Article 10.3390/mi11080744 1 MICROMACHINES, v.11, no.8 MICROMACHINES 11 8 N scie scopus 000579708500001 2-s2.0-85089466694 Chemistry, Analytical Nanoscience & Nanotechnology Instruments & Instrumentation Physics, Applied Chemistry Science & Technology - Other Topics Instruments & Instrumentation Physics Article SILICON NANOWIRES ANODES ARRAYS magnetically guided metal-assisted chemical etching bulk Si etching curved Si structure catalyst encapsulation