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[0085] In an exemplary process, the conductive bumps 124 may be formed by depositing the hard particles onto surfaces of the interposer leads 116. For example, a nickel electroplating process may be used to deposit the hard particles. In the electroplating process the hard particles and the contact surface are encapsulated in the nickel. If necessary, a photoresist may be used as a mask, using standard lithographic means, for masking portions of the interposer 112 during the electroplating to form the conductive bumps 124. The nickel may then be overplated with another material, such as gold, for example, to provide a corrosion-resistant surface. The presence of the hard particles makes for conductive bumps 124 that have a large number of sharp points 130 extending out of the surface of the conductive bumps 124. When brought into contact with the antenna 106 the sharp points penetrate into the material of the antenna, and/or penetrate an oxide film, such as an aluminum or copper oxide film, coating the surface of the antenna 106. Thus an electrical connection between the interposer leads 116 and the antenna 106 is accomplished.
[0086] The sharp points 130 may even be capable of extending through a bump-antenna adhesive 134 between the conductive bumps 124 and then antenna 106. The bump-antenna adhesive 134 may be a non-conductive adhesive, an isotropic electrically-conductive adhesive or an anisotropic electrically-conductive adhesive. The bump-antenna adhesive 134 may be a UV-cured adhesive or a heat-curable adhesive. The conductive bumps 124 may each have a height from about 5 to 25 microns (about 0.0002 to 0.001 inches). The interposer substrate 118 may have a thickness of from about 0.0005 inches to about 0.007 inches.
[0087] Formation of conductive bumps 124 such as those described above may be accomplished, for example, by use of WAFERPIERCE technology marketed by NanoPierce Technologies, Inc., of Denver, Colo. Such technology is described in greater detail in PCT Publication WO 02/25825, which is incorporated herein by reference in its entirety.
