SBIR Phase I: Colloidal Quantum Dot Emitters for Deep Ultraviolet Light Emitting Diodes

This Small Business Innovation Research Phase I research project seeks to develop a novel method of fabricating deep UV LEDs which will allow for wider wavelength ranges as well as provide higher efficiencies than current UV LED technologies. State of the art UV LEDs have wavelength ranges from 255nm to 365nm and are achieved through complex and expensive epitaxial growth of AlInGaN materials. External quantum efficiencies are low for these devices due to poor crystal quality, resulting in lower reliability and shorter lifetimes than visible LEDs. The objective of this project is to prove the feasibility of fabricating UV LEDs with a technique that includes the use of colloidal quantum dots and bypasses the need for complicated multiple quantum well epitaxial active layers. This method would reduce the effect the crystal quality has on external quantum efficiency. The ability to fabricate higher efficiency deep UV LEDs opens up a wide array of UV LEDs can be used for disinfection applications, such as air, water, and surfaces. These applications are currently being accomplished with expensive, short lifetime UV lamps or with environmentally harmful chemicals. LEDs provide a mechanism for disinfection that does not impact the environment, as well as offering longer lifetimes, and cost advantages. Security applications are also producing a growing market for UV LEDs. Emission in the deep UV range enables the development of non-line of sight communication devices as well as biological agent detection.