Page 8 - Impression July 2020

SCATTER

A New Material for X-Ray Detectors

Researchers at Los Alamos National Laboratory and Argonne National Laboratory have designed a
new X-ray detector prototype that might revolutionize medical imaging. The detector would replace
the current silicon-based technology with a structure built around a thin film of the mineral

perovskite. The result is a detector that is a hundred times more sensitivity than conventional
silicon-based detectors. In addition, the new perovskite detector does not require an outside power
source to produce electrical signals in response to X-rays.

The highly sensitivity perovskite detectors could enable images that require a tiny fraction of the

exposure that accompanies conventional X-ray imaging. Because perovskite is rich in heavy
elements, such as lead and iodine, X-rays that easily pass through silicon undetected are more

readily absorbed, and detected, in perovskite. As a result, perovskite significantly outperforms
silicon, particularly at detecting high-energy X-rays. Another benefit is that perovskite films can be
deposited on surfaces by spraying solutions that cure and leave thin layers of the material behind. As

a result, the thin-layer detectors will be much easier and cheaper to produce than silicon-based
detectors, which require high-temperature metal deposition under vacuum conditions.

Dozens of groups around the world are currently exploring this area, and major X-ray imaging
manufacturers, including Samsung and Siemens, are considering perovskite for their next-generation

machines. There are still a number of hurdles to cross before perovskite detectors will be ready for
market. One big obstacle is that some perovskites are sensitive to moisture. With many methods

underdevelopment to address this issue, it may not be long until this revolutionary product begins to
change imaging around the world.