Macroporous-based micromachining on full wafers

This paper reports on a technique of macroporous-based micromachining for full wafers. A 3.6 kW xenon lamp of whose intensity can be varied is employed to generate electronic holes during the etching. In order to apply a uniform electric field to whole 3 in. wafer, a mesh electrode is formed on the backside of the wafer after implantation of an n(+) layer. Furthermore, a surfactant is added to an electrolyte to remove hydrogen bubbles from the wafer surface and the etched holes. These methods improve the uniformity of the etched structures. This shows that electrochemical etching can be used not only in the laboratory but also in manufacturing processes. (C) 2001 Elsevier Science B.V. All rights reserved.