Solid-State UV Lamp Presents Sterilization Alternative

A new solid-state UV lamp could provide a cheaper and safer option for surface sterilization.

Developed by a team from the Nagoya Institute of Technology, the lamp is said to achieve the shortest light wavelengths ever recorded for a solid-state phosphor lamp, 140 to 220 nm. This is called the vacuum range because light of that frequency propagates in a vacuum, but is quickly absorbed by oxygen in the air.

Used over short ranges in air, vacuum UV light generates highly reactive oxygen radicals that can completely destroy microbes contaminating a surface. This makes the new lamp suitable for sterilizing medical devices, cleaning semiconductor substrates and other industrial applications, researchers said.

A diagram of the solid-state UV lamp. Courtesy of AIP Publishing.

“Our lamp is a promising light source in terms of lifetime, size, heat conduction and stability,” said Shingo Ono of the Nagoya Institute of Technology. “[It] has the potential to be an excellent alternate light source to low-pressure mercury lamps, excimer lamps and deuterium lamps.”

The new lamp avoids use of toxic gases and expensive rare earth elements. It was fabricated using pulsed laser deposition of a thin film of KMgF₃ on a MgF₂ substrate. It also employs carbon nanofibers as a field emitter.

The work is published in APL-Materials (doi: 10.1063/1.4871915).