Electrochemical mechanical micromachining based on confined etchant layer technique

Abstract

The confined etchant layertechnique (CELT) has been proved an effective electrochemical microfabrication method since its first publication at Faraday Discussions in 1992. Recently, we have developed CELT as an electrochemical mechanical micromachining (ECMM) method by replacing the cutting tool used in conventional mechanical machining with an electrode, which can perform lathing, planing and polishing. Through the coupling between the electrochemically induced chemical etching processes and mechanical motion, ECMM can also obtain a regular surface in one step. Taking advantage of CELT, machining tolerance and surface roughness can reach micro- or nano-meter scale.

Study on a non-contact polishing method using motion coupling confined etchant layer technique

“…During the scavenging reaction, the etchant concentration gradient increased significantly and the material removal rate (MRR) is limited into atomic level by its distance-sensitiveness, which indicates the capability for its polishing application. In earlier research, Yuan et al (2013) verified CELT polishing application on n-GaAs substrates. It has been proved that using plate electrodes in static mode is difficult to achieve uniform result, which is explained by the poor diffusion condition between the substrate and the electrode.…”

Research advances of electrochemical micro/nanofabrication based on confined etchant layer technique

“…CELT微纳加工设备的核心部分是纳米操纵系统, 包括多维超精密定位和信息反馈控制; 此外, 还包括 电化学工作站和计算机控制系统 [31,32] [33] . 调平时, 控制探针电极的位 置不变, 当工件旋转时, 探针电极的电流呈周期性变 化, 表明不同位置基底与探针距离的变化, 并可据此 检测基底水平度并进行调平操作(图2).…”

“…另 外, 湿法化学腐蚀过程不可控, 仅作为半导体工业中 的晶圆片清洗工艺. 因此, 湿法化学刻蚀微纳加工的 关键技术问题是有效控制刻蚀剂的扩散 [31,39] , 而约束 http://engine.scichina.com/doi/10.1360/N032016-00217 http://engine.scichina.com/doi/10.1360/N032016-00217…”

Electrochemical buckling microfabrication

“…For years we have developed a confined etchant layer technique (CELT) to solve the problem: 20–24 firstly, the etchant is generated on the surface of a mold electrode by an electrochemical reaction. Secondly, the diffusion distance of the etchant is confined to the micron or nanometer scale by a subsequent homogeneous reaction.…”