A Wireless-Enabled Microdischarge-Based Radiation Detector Utilizing Stacked Electrode Arrays for Enhanced Detection Efficiency

This paper describes a wireless gas-based beta/ gamma radiation detector that uses an arrayed electrode structure to demonstrate a scalable path for increasing detection efficiency. The device uses an assembly of stainless-steel electrodes and a glass spacer structure within a TO-5 package. The components are manufactured by commercial micromachining methods, e.g., the electrodes are photochemically etched whereas the spacer structure is ultrasonically machined. Two different fill gases are evaluated near 760 torr-i.e., Ar and P-10. The detector diameter and height are 9 and 9.6 mm, respectively, and its weight is 1.01 g. With a 99-μCi Cs-137 source (which is a beta and gamma emitter), the detector provides >; 78 cpm to a hardwired inter face at a source-detector distance of 30.5 cm. Receiver operating characteristics evaluated for integration times ranging from 30 to 180 s have shown to improve with longer integration time. The estimated intrinsic detection efficiency (i.e., with the back ground rate subtracted) is ≈4%, as measured with the biasing arrangement described in this paper. Portable powering modules developed for these detectors are also presented. During operation, gas microdischarges between the electrodes, which are initiated by incident radiation, transmit wideband wireless signals. Wireless signaling has been demonstrated to exhibit fast transient durations on the order of tens of nanoseconds. Wireless-enabled radiation sensors are envisioned for use in rapidly deployable mobile net work configurations.