New device concepts and materials for the fabrication of compact high-frequency vacuum sources and micro-nano-integrated X-ray sources are of particular interest for broadband communication, security screening of packages and chemical materials, biomedical examination, and other applications. This article integrates results on GaN- and ZnO-based nano and self-assembled structures. They were used as field emitter tips for cold electron emission at high local electric fields as well as for photoassisted field emitters to generate bunched electrons directly from the emitter tip. The results on functional field emitters as cold electron sources will be presented. They are key elements for building, among other miniaturized vacuum tubes. Such miniaturized vacuum tubes can achieve high power at high cutoff frequencies and overcome the limitations of conventional GaAs- or InP-based solid-state devices. Furthermore, new functional X-ray sources with ultrashort pulses will allow 3D imaging with low radiation doses.
Electron field emission, nanorod, GaN, ZnO, photoassisted field emission, electric field enhancement
YILMAZOGLU, OKTAY; EVTUKH, ANATOLI; AL-DAFFAIE, SHIHAB; BIETHAN, JENS-PETER; PAVLIDIS, DIMITRIS; LITOVCHENKO, VLADIMIR; and HARTNAGEL, HANS L.
"Electron field emission from nanostructured semiconductors under photo illumination,"
Turkish Journal of Physics: Vol. 38:
3, Article 19.
Available at: https://journals.tubitak.gov.tr/physics/vol38/iss3/19