Synthesis of high electron yield nanomaterials for radiation detector applications

The secondary electron emission (SEE) yield of coaxially AlN or GaN coated ZnO nanoneedle heterostructures has been measured. The SEE yield of the heterostructures is enhanced significantly by the inherited nanostructures from the ZnO nanoneedle templates as compared to the AlN and GaN thin films on Si substrates. The dependence of the SEE yield of the heterostructures samples on the primary electron incidence angle does not obey the conventionally power law relationship in insulators. The SEE yield enhancement is attributed to the nanostructured topography phenomenon. The findings should shed light on the development of highly efficient radiation detectors based on the SEE principle