Wireless Dosimeter
In this work, a new floating-gate (FG) MOSFET based wireless dosimeter system-in-package (SiP) is presented. This miniature and completely integrated wireless dosimeter SiP comprises a CMOS FG radiation sensor and transmitter (TX) in a low-temperature co-fired ceramic (LTCC) package.
Overview
In the treatment of cancer patients by means of high energy radiation, precise knowledge of the dose and location of radiation experienced by the body is essential. Typically, this measurement is made by a wired sensor to record the high energy radiation dose. These radiation sensors are small enough to be placed on any part of the body during a radiotherapy session, helping doctors to target malignant tumors by providing real-time data on the radiation doses reaching the organs. These radiation measurement systems are called dosimeters. While these dosimeters have reasonable sensitivity, they consume a lot of power and the wire that connects to them is large and can deflect or scatter the radiation away from the targeted region during the irradiation process. To avoid these ill effects and to relieve the patients from a cluster of wires on their bodies, a short-range radio for transmitting the sensor data is an ideal solution.
This project demonstrated new floating gate radiation sensors with considerably reduced power consumption. These were integrated with signal processing electronics on the same chip. A custom CMOS transmitter chip with an on-chip antenna was integrated with the sensor chip in an LTCC package to demonstrate the first of its kind wireless dosimeter.
The project of “Wireless Dosimeter” won the ITAC SMC Award at Canadian Microelectronics Corporation TEXPO (2007).
Further Information:
A. Shamim, M. Arsalan, L. Roy, G. Tarr, “Wireless Dosimeter: System on Chip versus System in Package for Biomedical and Space Applications,” IEEE Transactions on Circuits & Systems II, vol.55, pp.643-647, Jul 2008.
