Fabrication of high quality X-ray source by gated vertically aligned carbon nanotube field emitters

Abstract

We fabricated a cold cathode-driven x-ray source with vertically aligned carbon nanotubes (VACNTs). Dose and spatial resolution characteristics are compared to commercially available portable x-ray sources, and our system outperformed its counterparts. At the same 1.0 mAs condition, our x-ray source represented a dose rate of 0.37 mGy/s, which is 7.8 and 2.4 times greater than that of the thermionic emitter and paste carbon nanotubes based commercial x-ray sources, respectively. In addition, our x-ray source represented better image resolution by achieving a nominal focal spot size of 0.35 mm. We believe that high quality x-ray properties were attained, thanks to the narrow electron beam divergence and high reduced brightness of the electrons from VACNTs, and that this will open up advanced x-ray applications.