Ionizing radiation sensing has many applications in a
variety of industries. Low dose sensing is important for nuclear materials
detection and security. Some space applications require measurement of the flux
and direction of high energy radiation. Furthermore, it is essential to
determine the exact location and amount of radiation directed toward human
tissues in radiation therapies used for cancer treatment. Presently, there are
several different types of sensors that are utilized for these different types
of radiation detection; however some are very expensive and large, while others
demand extensive post-processing of the information acquired.
Researchers at Arizona State University have designed a film
bulk acoustic-wave resonator (FBAR) that detects high energy radiation focused
at the device by trapping charge produced by the radiation. The trapped charge
changes the operating attributes of the device by altering the static
capacitance, which modifies the resonant frequency of the FBAR. The system
employs zinc oxide (ZnO) as the piezoelectric material in charge of creating the
standing acoustic wave. This device is much smaller than current sensors and is
constructed completely by MicroElectroMechanical System (MEMS) techniques. It
also exhibits the ability to perform passive telemetry.
Potential Applications
- Biomedical Applications
- Space Exploration
- National Security MonitoringM
Benefits and Advantages
- Much smaller than current gamma detectors
- Good passive telemetry ability
- Ease of fabrication using known MEMS
techniques