Rf and/or rf identification tag/device having an integrated interposer, and methods for making and using the same

Abstract

A MOS RF surveillance and/or identification tag, and methods for its manufacture and use. The tag generally includes an interposer, an antenna and/or inductor on the interposer, and integrated circuitry on the interposer in a location other than the antenna and/or inductor. The integrated circuitry generally has a lowest layer in physical contact with the interposer surface. The method of manufacture generally includes forming a lowest layer of integrated circuitry on an interposer, forming successive layers of the integrated circuitry on the lowest layer of integrated circuitry, and attaching an electrically conductive functional layer to the interposer. Alternatively, an electrically conductive structure may be formed from a functional layer attached to the interposer. The method of use generally includes causing and/or inducing a current in the present tag sufficient for it to generate, reflect or modulate a detectable electromagnetic signal, detecting the signal, and optionally, processing information conveyed by the detectable electromagnetic signal. The present invention advantageously provides a low cost RFID tag capable of operating at MHz frequencies that can be manufactured in a shorter time period than conventional RFID tags that manufacture all active electrical devices on a conventional wafer.