Herein, the bulk micromachining of Si by a magnetically guided metal-assisted chemical etching (MACE) process is demonstrated. To improve the etching performance of Si, a trilayer metal catalyst (Au/Fe/Au) is deposited on Si to obtain faster etching speed by a magnetic pulling force. An annealing process is performed on the catalyst to obtain rougher surface morphologies due to agglomeration and improve ferromagnetic properties, which increase the etching rate for magnetically guided MACE. By the bulk micromachining of Si through the introduced direction-controlled MACE technique with the annealing process, Si microsheet arrays are fabricated. We show that vertically aligned Si microsheet arrays are produced within 17 h of etching, even at an etching thickness of over 500 μm, by magnetically guided MACE under a fixed vertical magnetic pulling force. Moreover, introducing magnetically guided MACE can fabricate Si microhole arrays in various dimensions by adjusting pattern size and etching time. Curved Si microhole arrays are fabricated by altering the direction of the magnetic pulling force by changing the position of the hard magnet, which shows that the etching direction is effectively adjusted during the bulk micromachining of Si. The etching method developed here can be applied to cost-effective bulk Si slicing processes.

中文翻译：

---

退火驱动的磁控金属辅助化学刻蚀对硅进行整体微细加工

在此，说明了通过磁引导金属辅助化学蚀刻（MACE）工艺对Si进行的整体微细加工。为了提高Si的蚀刻性能，三层金属催化剂（Au / Fe / Au）沉积在Si上，以通过磁拉力获得更快的蚀刻速度。对催化剂进行退火处理，以获得由于团聚而产生的较粗糙的表面形貌并改善铁磁性能，从而提高了磁导MACE的蚀刻速率。通过采用退火工艺引入方向控制的MACE技术对硅进行整体微细加工，制造出了硅微片阵列。我们显示，即使在蚀刻厚度超过500μm的情况下，在蚀刻后的17小时内也会产生垂直排列的Si微片阵列，在固定的垂直磁力拉力作用下通过磁导MACE进行。而且，引入磁导的MACE可以通过调节图案尺寸和蚀刻时间来制造各种尺寸的Si微孔阵列。通过改变硬磁体的位置来改变磁拉力的方向来制造弯曲的Si微孔阵列，这表明在Si的整体微加工过程中有效地调整了蚀刻方向。此处开发的蚀刻方法可应用于具有成本效益的块状Si切片工艺。这表明在硅的整体微加工过程中有效地调节了蚀刻方向。此处开发的蚀刻方法可应用于具有成本效益的块状Si切片工艺。这表明在硅的整体微加工过程中有效地调节了蚀刻方向。此处开发的蚀刻方法可应用于具有成本效益的块状Si切片工艺。