Electrical engineer recognized for paper detailing enhancements to everyday nanoelectronics

By Peter Murphy

Complementary metal oxide semiconductors (CMOS) are used in some of the most common and essential electronics, including smartphones and computers. Many of the current CMOS technologies are three-dimensional and silicon-based, but these semiconductors may not maximize energy efficiency and sometimes affect how different devices run. UB engineers are examining ways to evolve the energy band structure of smaller two-dimensional (2D) semiconductors, making them more energy efficient.

“This work demonstrates the great potential of 2D materials and their doping engineering to feasibly integrate with the existing CMOS technology and eventually improve the efficiency of future nanoelectronics,” says Huamin Li, assistant professor in the Department of Electrical Engineering and corresponding author on “Plasma-induced energy band evolution for two-dimensional heterogeneous anti-ambipolar transistors.”

The study, featuring additional School of Engineering and Applied Sciences co-authors, assistant professor in mechanical and aerospace engineering Jun Liu and assistant professor in materials design and innovation Fei Yao, discusses the researchers’ work using a technique typically associated with 3D CMOS to change the electrical properties of the 2D semiconductors, specifically, transition metal dichalcogenides like MoS2 and WSe2—two different types of 2D semiconductors.

“We exploit an oxygen plasma treatment, a typical and mature process in CMOS technology, to introduce a doping effect on the 2D semiconductors, and evolve the energy band structure of 2D WSe2/MoS2 heterojunctions,” Li says.

The researchers use the doping effect to intentionally add impurities that change the electrical properties of the WSe2 semiconductor. Researchers then combine this semiconductor with the MoS2 semiconductor. The interface between each semiconductor forms a heterojunction which can determine the design of different electronic components. Li believes this work could mark a turning point in the use of 2D materials and their doping engineering as effective semiconductors in traditional CMOS technology.

“As an emerging device concept, this offers the possibility of achieving higher data storage density and constructing high-frequency oscillators, energy-efficient switches and multivalued logic devices and circuits.”

Both the Journal of Vacuum Science & Technology B and the Beneath the American Vacuum Society’s (AVS) Surface newsletter are distributed to international scientists, engineers and instrument manufacturers. According to the journal, it covers “microelectronics and nanometer structures with an emphasis on processing, measurement and phenomena associated with micrometer, nanometer structures and devices and vacuum science and technology.”