Application of ion conductors for microfabrication of solid surface

The present paper describes novel microfabrication techniques which utilize an ion migration at the microcontact between ion conductor and target solid. Two different methods have been recently proposed by our group. One is a solid state electrochemical route for pinpoint doping using an ion conductor. In this approach, an electric field is applied to the solid­solid interface between the cation conductor and target solid, inducing the injection of cations into the target. A significant advantage of this technique is that it enables pinpoint doping into desired locations within a solid target using the ion conductor having an extremely small contact area. On the other hand, we have also investigated an electrochemical microstructuring (i.e., micromachining) of metal surface through an anodic reaction of metal substrate attached to the needle-like ion conductor. The metal substrate is electrochemically oxidized, and then dissolves as Mn+ into the ion conductor placed at the cathodic side. As a result of the continuous application of electric field, the metal surface is drilled according to the apex form of the ion conductor employed. This paper reveals the characteristics (merits and demerits) of the present techniques vis-a-vis conventional techniques for doping or micromachining.