The anodic dissolution and electrochemical behaviors of micro needle probe

• Main Authors: Sheng Yuan Yang, 楊勝淵
• Other Authors: Ching An Huang
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/06597738641251650555

碩士 === 長庚大學 === 機械工程研究所 === 93 === Over the past few years, Micro-Electro-Mechanical-Systems (MEMS) has been studied by many scholars. MEMS is one of the next generation manufacturing technology that fabricate light, small, precise, and high aspect ratio parts. In this study, we proposed electrochemical etching and chemical etching method to fabricate needle probes in diameter about 100 micrometers. The needle electrode made from harden-treated high carbon tool steel (SK 4) was preformed with turning machine before chemical etching. The anodic dissolution of needle electrode in our proposed etchants can be classified in two types: thinning with and without deburring. Furthermore, these dissolution types can be differentiated obviously from their electrochemical behaviors and AES analyses. Based on the electrochemical behavior and dissolution type, an etchant can fabricate needle probe with sharp tip and high aspect-ratio geometry was successfully developed. The needle electrode made from W-Re (ReW3) alloy was also successfully produced by electrochemical etching with NaOH electrolyte. The suitable electrolyte for W-Re alloy was evaluated by anodic polarization, moreover, tip geometry of needle electrode can be controlled by varying electrochemical parameters such as cathode area and position, distance between electrodes.