Electric Fields in Nanodevices Mapped with Holography Technique

As technology scales down, nanodevices are on the rise. With sizes between one and 100 nanometers, these devices could help make future computers faster, improve memory capacity, and reduce energy consumption of electronic devices.

While the physical characteristics of nanodevices are well understood, little is known about their electromagnetic fields at nanoscales, which is essential for the development of more advanced devices. To improve this understanding at nanoscales, Brodovoi et al. developed a technique to measure the electric fields of real devices using electron holography.

“Being able to see the distribution of the electric potential or field inside a functioning component is like observing the human heart in operation and not just listening to the heartbeat with a stethoscope,” said author Christophe Gatel.

With the method, a device is prepped with a focused ion beam to make it thin enough for electron transparency before being bonded to a transmission electron microscopy holder. By biasing the device and any connected device, the authors use electron holography to measure the electric potential distribution. This allows measurements of capacitance and surface charge density to be quantitatively made on nanoscales.

“The developed methodology and results are important for the development and optimization of new microelectronics devices in terms of reliability, speed, and power consumption,” Gatel said. “We hope that this work, which bridges a gap between industry and fundamental physics, may also find applications for studying other types of devices as well.”

The authors plant to study electric fields in metal–oxide–silicon transistors and phase change memories and continue working to improve the sensitivity and increase temporal measurements.

Source: “Mapping electric fields in real nanodevices by operando electron holography,” by Maria Brodovoi, Kilian Gruel, Aurélien Masseboeuf, Lucas Chapuis, Martin Hÿtch, Frédéric Lorut, and Christophe Gatel, Applied Physics Letters (2022). The article can be accessed at https://doi.org/10.1063/5.0092019 .