There seems to be UV light at the end of the tunnel.
EDIT: the question is if the production of 350-400nm will be effected by this, witch operate at 265nm - Anyway
Edit2: wiki UV def.
- UVA: 380 nm - 320 nm
- UVB: 320 nm - 280 nm
- UVC: 280 nm - 185 nm
http://news.ncsu.edu/releases/wms-collazo-uv/
Release Date: 05.14.2012
Research Opens Doors To UV Disinfection Using LED Technology
Research from North Carolina State University will allow the development of
energy-efficient LED devices that use ultraviolet (UV) light to kill pathogens
such as bacteria and viruses. The technology has a wide array of applications
ranging from drinking-water treatment to sterilizing surgical tools.
“UV treatment utilizing LEDs would be more cost-effective, energy efficient and
longer lasting,” says Dr. Ramón Collazo, an assistant professor of materials science
and engineering at NC State and lead author of a paper describing the research.
“Our work would also allow for the development of robust and portable water-treatment
technologies for use in developing countries.”
Researchers found that trace carbon atoms in the substrate of
the aluminum nitride semiconductors block key wavelengths of ultraviolet light.
LEDs utilize aluminum nitride (AlN) as a semiconductor, because the material
can handle a lot of power and create light in a wide spectrum of colors, particularly
in the UV range. However, technologies that use AlN LEDs to create UV light have
been severely limited because the substrates that served as the foundation for
these semiconductors absorbed wavelengths of UV light that are crucial to applications
in sterilization and water treatment technologies.
A team of researchers from North Carolina and Japan has developed a solution to the problem.
Using computer simulation, they determined that trace carbon atoms in the crystalline structure
of the AlN substrate were responsible for absorbing most of the relevant UV light. By eliminating
the carbon in the substrate, the team was able to significantly improve the amount of UV light
that can pass through the substrate at the desired wavelengths.
“Once we identified the problem, it was relatively easy and inexpensive to address,”
says Dr. Zlatko Sitar, Kobe Steel Distinguished Professor of Materials Science and
Engineering at NC State and co-author of the paper.
Commercial technologies incorporating this research are currently being developed
by HexaTech Inc., a spin-off company from NC State.
“This is a problem that’s been around for more than 30 years, and we were able
to solve it by integrating advanced computation, materials synthesis and
characterization,” says Dr. Doug Irving, assistant professor of materials science
and engineering at NC State and co-author of the paper. “I think we’ll see more
work in this vein as the
Materials Genome Initiative moves forward, and that
this approach will accelerate the development of new materials and related technologies.”
The paper, “
On the origin of the 265 nm absorption band in AlN bulk crystals,”
is published online in
Applied Physics Letters.