The device features a new readout technique based on the change in the electric current flowing through the bimorph and the contact pad. Various read-out techniques such as laser-beam deflection, interferometry, piezoresistive, piezoelectric, capacitance, and field-effect transistors have been exploited to detect bimorph deflections, but these methods typically involve either complex fabrication steps or time consuming optical alignment.

"The thermal sensor demonstrated here is a strong candidate for thermal switching and triggered detection thanks to the relative ease of fabrication and the direct electrical readout," said Jr-Hau He. "We believe that the theoretical and experimental understanding gained from the present research will facilitate sensors/switches at the nanoscale for applications such as thermal control in nanoelectronics and nanothermal probing."

The device architecture suits thermal imaging or switching in an arrayed manner. In addition, the technology can be adapted to realize a highly sensitive chemical and biological sensing system by altering the sensitive layer.

This research is a result of the collaboration between National Taiwan University, Taiwan, and Georgia Institute of Technology, USA.

The researchers presented their work in Nanotechnology.