Large area deep ultraviolet light of Al$_{0.47}$Ga$_{0.53}$N/Al$_{0.56}$Ga$_{0.44}$N multi quantum well with carbon nanotube electron beam pumping

Large area deep ultraviolet (DUV) light is generated by carbon nanotube (CNT) cold cathode electron beam (C-beam) irradiation on Al$_{0.47}$Ga$_{0.53}$N/Al$_{0.56}$Ga$_{0.44}$N multi quantum wells (MQWs) anode. We developed areal electron beam (EB) with CNT cold cathode emitters. The CNT emitters on silicon wafer were deposited with an area of 188 mm$^2$ , and these were vertically aligned and had conical structures. We optimized the C-beam irradiation conditions to effectively excite AlGaN MQWs. When AlGaN MQWs were excited using an anode voltage of 3 kV and an anode current of 0.8 mA, DUV with a wavelength of 278.7 nm was generated in a large area of 303 mm$^2$ . This DUV area is more than 11 times larger than the light emitting area of conventional EB pumped light sources and UV-LEDs.