Micro Fabrication of Nickel Cantilever Arrays and Tips

Abstract

An array of four metal cantilevers was fabricated on a silicon substrate. Cantilever dimensions are 30 micrometer wide, 225 micrometer long, and 2 to 30 micrometer thick with 30mum spacing. Each cantilever is fabricated using the electroplating of nickel into a photoresist mold. After the electroplating of Ni, the probe chips are freed by deep RIE. Each chip can be installed in the commercial AFM. The fabrication of a Ni tip for the probe was developed using isotropic wet etching. Ferric chloride has good selectivity for the nickel against the mask materials used. Negative pholoresist and PECVD silicon oxide were used as a mask. Metal tip size and shape could be controlled through the etching time, etchant concentration, and solution agitation.