Microfabrication by High Rate Anodic Dissolution: Fundamentals and Applications

Abstract

This paper presents a review of the basic principles of electrochemical metal removal processes and their application in microfabrication. After a brief description of anodic behavior of metals, the influence of mass transport, surface films and current distribution on microfabrication performance are discussed. Some examples of microelectronic component fabrication are presented that demonstrate the challenges and opportunities offered by high rate anodic dissolution processes.

Review—Through-Mask Electrochemical Micromachining

“…The influence of these variables on surface finish has been discussed extensively for related processes involving electrochemical metal removal such as ECM, EP and EMM. 1,2,[13][14][15][16]18,[20][21][22]92 In general, the magnitude of the current density along the anode determines the mode of metal removal, which is either characterized by active or mass-transfer limited dissolution. 1,2,20,92 Below the limiting current density the anode dissolves in the active state.…”

“…1,2,[13][14][15][16]18,[20][21][22]92 In general, the magnitude of the current density along the anode determines the mode of metal removal, which is either characterized by active or mass-transfer limited dissolution. 1,2,20,92 Below the limiting current density the anode dissolves in the active state. In this case, the dissolution rate is controlled by surface-kinetic steps, such as charge transfer.…”

“…161 Apart from metalization layers, TMEMM was also applied to the fabrication of memory arrays, 204 resistance elements, 205,206 magnetic recording heads, 160,207,208 diodes, 209 detachable electrical contacts, 112,113 and slider suspensions. 113 Several review articles 1,14,15,19,80,92,210 have summarized microelectronic components machined via TMEMM.…”