A Medipix-Based Small Personal Space Radiation Dosimeter

This SBIR effort will take the first step in improving the existing Medipix dosimeter technology in terms of advancing the technique now used to couple the actual sensitive detector material to the underlying readout electronics. Prototypes of current Medipix2-based devices have been developed using "bump-bonding" techniques, and we will improve this design by employing direct epitaxial deposition of the detector layers onto the Medipix2 wafers. This will allow us to deploy very specialized detector structures within the detector layers that can enhance the efficiency and resolution of the device for neutron detection, as well as improving both the charge and energy resolution for charged particles. This includes the application of high hydrogen content polymer coatings to enhance neutron sensitivity. The epitaxial technique will also produce more mechanically robust detectors and potentially avoid one of the significant failure modes for such hardware, namely loss of contact at the bump-bonding sites. Versions of the current bump-bonded prototypes exist that are essentially the size of a typical USB Flash-Memory plug-in device, and like those "USB-Smart-Drives," these prototypes can be fully powered and read-out electronically via standard USB interfaces such as found on most current laptop computers