US BOLB Company Announced Major Technological Breakthroughs In Deep Ultraviolet Light-emitting Diodes

- Nov 11, 2019-

The new fully transparent conductive layer boosts light efficiency by nearly 3 times and is far ahead in the industry.

American BOLB Corporation announced an external quantum efficiency (EQE) of 12.2% on a fully transparent structured deep ultraviolet light emitting diode (UVC LED). This key fundamental technology breakthrough paves the way for UVC LEDs to achieve near-visible LED efficiency in the next few years, and will further expand the application of UVC LED sterilization technology in people's daily lives.

In the past two decades, researchers' efforts to improve the efficacy of deep-UV LED devices have been constrained by narrow-band hole carrier supply layers. This layer causes a strong absorption of light on the side of the P-type semiconductor in the chip structure. Prior to BOLB's breakthrough, various attempts to remove the narrowband layer always resulted in high operating voltages and significantly degraded LED current-voltage characteristics, and the resulting high heat would result in shorter device lifetimes. BOLB's new major breakthrough achieved the complete UVC LED structure, which is completely transparent to the best germicidal wavelength UV, and achieves 12.2% external quantum efficiency (EQE) and 9.5% electricity on the first generation based on this technology. - Light Conversion Efficiency (WPE).

For example, with an extension of 269 nm, a 20 mA current drive is required to obtain 10-11 mW of UVC optical power from a single 0.125 mm2 LED production model while maintaining a forward voltage of 5.8V. This electro-optical conversion efficiency is three to five times that of other similar products currently on the market, greatly improving the cost performance of the product. If you use a multi-core module, or use a large chip to run at higher drive currents, this technology can achieve unprecedented high UV output power. In other words, compared to other similar products, BOLB can achieve the same output power with a minimum number of chips and the lowest current in a band more suitable for sterilization. This breakthrough provides a solid foundation for further optimization of subsequent high-power UVC devices and achieving target performance of 50% EQE or higher.

The UVC band LED bactericidal effect far exceeds the near-ultraviolet band (UVA and UVB), and its physical inactivation mechanism is equally effective against emerging multi-drug resistant pathogens. At present, this product has entered small batch production after trial use by strategic cooperation customers. BOLB will continue to improve the light-emitting efficiency of deep-UV LEDs on the basis of breakthroughs, and expand its wide-ranging applications in the medical, catering, food, pharmaceutical packaging, agricultural and livestock, and home appliances industries with the cooperation of related fields. Make the company a leader in the new tens of billions of low-pollution clean technology markets.