Cathodoluminescence of a 2 inch ultraviolet-light-source tube based on the integration of AlGaN materials and carbon nanotube field emitters

Abstract

High efficiency and mass-scale production ultraviolet (UV) light sources have become a basic requirement for various applications, and as such have attracted considerable technological interest. Here, a flat 2 inch UV-light-source tube-based triode structure operating at 330 nm with a pulse-scan mode was achieved by integrating the AlGaN/GaN multi-quantum well (MQW) heterostructure as a cathodoluminescence (CL) layer and carbon nanotube (CNT) field emitters. The AlGaN/GaN MQW heterostructure CL layer was grown on a high-quality 2 inch AlN/sapphire template through metal–organic chemical vapor deposition. The CNT emitters were fabricated on the metal substrate using a cost-effective print screen method. The advantages of these emitters include their high stable emission efficiency for large-scale production, cold emission nature, controllable emission by the electric field, and environmentally friendly nature. This promising and effective integration demonstrates an output power of 590 mW and a power efficiency of 2.45% with a low consumption energy of 24 W (anode current 3 mA; anode voltage 8 kV) in pulse-scan mode. This work is the first step toward realizing future mass-scale and high efficiency UV light source tubes over a wide range of wavelengths.