Crystal IS has announced the Klaran WD family of ultraviolet (UV) LEDs with the WD suffix indicating the target application of water disinfection. The new products emit in the UV-C band, or what is sometimes called deep UV, and those bands are known to destroy the DNA in germs and pathogens. The company said that the new LEDs will hit the price/performance milestone of $0.25/mW of radiometric power that is well below what has been projected as the point where volume production UV-C-LED-based water purification products would commence.
As we have written repeatedly, the UV-C band (100–280 nm) has potentially the greatest potential impact of the broad UV span that also includes UV-B (280–315 nm), and UV-A (315–400 nm). The longer-wavelength bands are already widely used in industrial applications such as curing, and obstacles to higher power, greater reliability, and lower cost have been easier for the industry to overcome. UV-C has been much tougher to tackle, although it has attracted a lot of challengers because of the unique and tiny form factor of LED sources and huge market potential.
Crystal IS has been focused on solving the performance, cost, and reliability issues through the use of a homogenous substrate. The company is growing AlN (aluminum nitride) epitaxial layers on AlN substrates. Such a move could provide a better lattice match that could result in better performance. Soraa has followed a similar strategy in visible LEDs using a GaN (gallium nitride)-on GaN strategy.
Read more HERE