Fabrication of Micro/Nanoelectrode Using Focused-ion-Beam Chemical Vapor Deposition, and its Application to Micro-ECDM

Abstract

Micro electro-chemical discharge machining (micro-ECDM) is a key technology in the precision manufacturing. The electrode, which is the key element for achieving a high-precision ECDM, attracts the interests of many researchers. However, regarding the fabrication techniques of the electrode, the achievable precisions are still resting on micrometer scale, the processes are not simple, or electrodes with high complex three-dimensional (3D) shapes are difficult to be obtained. Basing on such a background, in this work, focused-ion-beam chemical vapor deposition (FIB-CVD) which is an effective tool in fabricating 3D micro/nanostructure for achieving various micro/nanoelectromechanical devices (MEMS/NEMS), was first time introduced to fabricate micro/nanoelectrode and furthermore ECDM processes using FIB-CVD-fabricated electrodes could be attempted. Differing to the conventional metallic electrodes, micro/nanoelectrodes in the material of amorphous platinum (Pt) were obtained. Three electrodes with the same diameter 10μm and height 28μm were fabricated on the polished tip surfaces of stainless needles, and consequently applied to micro-ECDM with varied low open voltages 10, 12.5 and 15V. Microholes were fabricated on the 304 austenitic stainless steel. The hole diameter and the unilateral discharge gap were found to be almost linearly increasing with the increase of open voltage. In case of using the open voltage 10V, the unilateral discharge gap was found to be 6.6μm. Moreover, fabrications of pillar, horn, corner, array types of 3D nanoelectrodes were demonstrated. These results indicate the potentialities of 3D micro-ECDM using complex 3D micro/nanoelectrode, and a deeper study into the science of ECDM/EDM phenomenon at submicron scale.