Prestudy Graphen in radiation measurement

Important results from the project

The experiments and test structures were designed to shed light on questions regarding Radiation hardness of graphene-based conductors Effect of secondary radiation by graphene-based inks in dose measurement Feasibility of long graphene-based leads to sensor diodes No visible degradation of grafen conductors has been noticed in exposing the test objects to 50kGray. No secondary radiation, measured as isotropic deviation in dose, has been measured. Conductivity in long leads af grafenbased ink is sufficient for sensitive dose measurements.

Expected long term effects

Smearing in printing was observed, due to necessary high printing pressure, resulting in a minimum line width of 150 micron. Future tests with optimized PCB material and ink can most likely improve the pitch. The assembly technology needs to be improved for bumping. Long graphen leads have high enough conductiveness for dose measurement. If precision and assembly technology are improved, there is an advantage compared to designs with traditional materials. Higher accuracy in measurement can be achieved in the target application Head and Neck, wich is a clear business advantage.

Approach and implementation

Project phases: Design of test boards - Based on existing boards. Underestimated efforts with several redesigns. Manufacturing and assembly - Lack of availability at vendors caused unplanned waiting periods. Radiation according to plan. Analysis of graphen properties - Internally Acreo according to plan. Dose measurement - ScandiDos performed at UAS, wating for slots. Analysis of final results - In cooperation according to plan. Summary: Actual design time far longer than plannned. Other activities as planned, but logistics and waiting times extended the time schedule by far.