Researchers modify electronic properties using light

1 min read

Researchers from Sanken (The Institute of Scientific and Industrial Research) at Osaka University and Joanneum Research in Austria have been able to show how exposing an organic polymer to ultraviolet light can precisely modify its electronic properties.

According to the scientists involved this work may aid in the commercialisation of flexible electronics that can be used for real-time healthcare monitoring, along with data processing.

Because electronics are silicon based, they are very rigid, both in the literal sense of being inflexible, as well as having chemical properties that are not easily altered. Newer devices, including OLED displays, are made from carbon-based organic molecules with chemical properties than can be tuned by scientists to produce more efficient circuits. However, controlling the characteristics of organic transistors usually requires the integration of complex structures made of various materials.

The researchers led by Osaka University have been able to use UV light to precisely change the chemical structure of a dielectric polymer called PNDPE. The light breaks specific bonds in the polymer, which can then be rearranged into new versions, or create crosslinks between strands.

The longer the light is on, the more the polymer can be altered. By using a shadow mask, the UV light is applied to just the desired areas, tuning the circuit behaviour. This method can pattern transistors of the desired threshold voltage with high spatial resolution using just a single material.

“We have succeeded in controlling the characteristics of organic integrated circuits using persistent light-induced changes in the molecular structure itself,” explained study corresponding author Takafumi Uemura.

As a consequence smart versions of almost everything, from medicine bottles to safety vests could be possible

“Meeting the computational demands of ‘the Internet of Things’ will very likely require flexible electronic solutions,” senior author Tsuyoshi Sekitani said. "In particular, this technology can be applied to manufacturing methods for ultra-lightweight wearable healthcare devices."