Surveillance devices with multiple capacitors

摘要

The disclosure relates to surveillance and/or identification devices having capacitors connected in parallel or in series, and methods of making and using such devices. Devices with capacitors connected in parallel, where one capacitor is fabricated with a relatively thick capacitor dielectric and another is fabricated with a relatively thin capacitor dielectric achieve both a high-precision capacitance and a low breakdown voltage for relatively easy surveillance tag deactivation. Devices with capacitors connected in series result in increased lateral dimensions of a small capacitor. This makes the capacitor easier to fabricate using techniques that may have relatively limited resolution capabilities.

主权项

1. A surveillance and/or identification device, comprising:
a) an electrically conducting strap on a substrate; b) a lower capacitor electrode on or over the substrate, electrically connected to the strap; c) a first dielectric film on the substrate and on or over a portion of the strap, the first dielectric film exposing a portion of the strap and having an opening over a portion of the lower capacitor electrode; d) a capacitor dielectric film on the lower capacitor electrode in the opening, the capacitor dielectric film having a significantly smaller thickness than the first dielectric film; e) an upper capacitor electrode on the first dielectric film and the capacitor dielectric film, the upper capacitor electrode capacitively coupled to the lower capacitor electrode; and f) an antenna and/or inductor electrically connected to the upper capacitor electrode and the strap.