Hello Magali, NiFe electroplating is notorious for showing cupping, or lipping, effects as the film approaches edges of things like photoresist, or the edge of the wafer for that matter. One trick you could try would be to add a 1" strip of copper plating tape to the outer edges of the wafer, in the area of the problem, to increase the effective plateable area. Basically what will happen is the uneven plating will occur out on the tape and not on your wafer. The idea is somewhat similar to sputter depositing from a 8" target to a 6" wafer to increase uniformity, but in our example of using tape, the extra 1" around the wafer is sacrificial. If you have a more sophisticated cathode arrangement than an alligator clip, the tape can be replaced by cathode modifications, which will help maintain wafer to wafer thickness control, since the tape application is likely to add some variation from run to run. Regards, Justin Justin C. Borski MEMS Program Manager Advanced MicroSensors Inc. (508) 770 - 2088 -----Original Message----- From: Magali Brunet [mailto:mbrunet@nmrc.ucc.ie] Sent: Thursday, October 17, 2002 3:58 AM To: mems-talk@memsnet.org Subject: [mems-talk] Edges problem in through-mask NiFe electroplating Dear all, On a silicon wafer where a Cu seed layer is sputtered, I am depositing photoresist (8um thick) to create patterns and then electroplating NiFe through the patterns (5um thick). The deposit has an even thickness except at the edges where there is a big overplating. (kind of "dog hears") Does anyone have an idea on how to get rid of this edge problem? Thanks a lot in advance, Magali -- PEI Technologies, NMRC, Lee Maltings, University College, Cork, Ireland. Tel: +353 21 4 904279 Fax: +353 21 4 270271 email: mbrunet@nmrc.ie _______________________________________________ MEMS-talk@memsnet.org mailing list: to unsubscribe or change your list options, visit http://mail.mems-exchange.org/mailman/listinfo/mems-talk Hosted by the MEMS Exchange, providers of MEMS processing services. Visit us at http://www.memsnet.org/