Throughout the world, radiation exposure has been on the rise due to the increased use of nuclear power, medical procedures, nuclear weapons and natural disasters affecting power plants such as in Fukushima, Japan. Increased exposure to radiation has both short- and long-term detrimental effects on the human body and rapid diagnosis (triage) of an absorbed dose of radiation is critical for survivability. Thus, it is critical to have a fast, cost-effective and field-deployable personal dosimetry solution without the overhead of additional hardware or processing equipment. The project will develop a handheld, real-time radiation dosimetry solution using commercially available flash memory chips. Since memory chips are widely used in many embedded systems (e.g., smartphones) and wearable devices (e.g., fitness belts), this project’s concept could provide a paradigm shift in radiation dosimetry through distributed smart devices, which will be very useful for health monitoring, remote sensing, military applications, nuclear-reactor safety and space applications. In addition, the project has a strong educational component that includes the training of underrepresented students, the involvement of undergraduate students in research and the incorporation of the project's research findings into coursework.
The objective of this project is to develop a novel cost-effective radiation-dosimeter technology using the bit error rate of commercial flash memory. The dosimetry solution will provide real-time read-out of absorbed dose value, which is ideal for rapid diagnosis applications to minimize health risk for those who work closer to radiation environment. The technology can also facilitate a wireless sensor network (e.g., through smartphones), and transmit data to a central facility to provide better situational awareness over a larger area. The project takes advantage of the instrumentation and expertise at Oak Ridge National Laboratory to demonstrate the validity of a flash memory-based dosimetry concept through a series of radiation-exposure experiments. Both modeling and experimentation will be performed to determine the range of operation of the proposed dosimeter and to enhance its accuracy, sensitivity and selectivity. In addition, we propose novel measurement techniques in order to understand and quantify the (i) dose-enhancement effect when ionizing radiation goes through the back end of the line metal layers of a chip, (ii) directionality effects of the incident radiation beam on the memory and (iii) ionization vs. displacement damage effect in the flash-memory array. Thus, this research advances our knowledge on the radiation-matter interaction and the radiation-related reliability physics of semiconductor devices. The research will also enable a wireless, passive, in-situ, real-time radiation-dosimetry solution that can be customized for a wide range of applications including personnel dosimetry, safety, space and commercial applications.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
