X-ray generation using carbon-nanofiber-based flexible field emitters

Abstract

Carbon nanofibers were grown on flexible polyimide substrates using an ion-beam sputtering technique. Field emission measurement showed a fairly low threshold voltage of $1.5\mathrm{V}∕\mu \mathrm{m}$ with a current density of $1\mu \mathrm{A}∕{\mathrm{cm}}^2$ . The field enhancement factor was determined to be 4400. The emitter showed resilience when exploited as a high voltage electron source for x-ray generation. The x-ray generated by the flexible emitter is capable of delivering fine images of biological samples with superior sharpness, resolution, and contrast.