Bandgap Engineering Of A Graphene-Like Material For Future Electronic Devices
Researchers discovered that a new material that resembles graphene-like structure can be a potential candidate for implementing next generation electronic devices.
Silicon based semiconductor devices are reaching their limits of operation. Researchers and engineers are trying to find out potential materials that can enable faster and more efficient electronic devices. Till now, carbon-based materials are one of the most promising for the development of future electronic devices, due to their properties, including a high mechanical strength and a good electrical and thermal conductivity.
In carbon-based materials, graphene is preferable as it presents high flexibility and transparency. But graphene does have a medium, which means that the material provides less control in the devices implemented. Recent studies have evaluated the scope of an alternative two-dimensional (2D) material that resembles graphene, known as C3N. This material consists of a uniform distribution of carbon and nitrogen atoms, arranged in a graphene-like structure.
Researchers at University of Queensland in Australia, East China Normal University, Shanghai Institute of Microsystem and Information Technology and other institutes in China have indicated that the bandgap of 2D C3N can be altered by changing their stacking order or applying an electric field to them.
The researchers carried out various theoretical calculations and simulations in order to investigate the potential of C3N for electronic devices. They found that this material has a wide bandgap tuning range, controllable on/off ratios, high carrier mobilities and photoelectronic detection capabilities.
The research has been published in the journal Nature Electronics, where they proposed two different strategies for engineering the bandgap of C3N bilayers. The first strategy consists in tuning the stacking configuration or twist angle between top and bottom C3N layers.
“Fabrication of layered 2D materials with required twist angles has been achieved using the transfer method or atomic force microscope (AFM) tip manipulation techniques,” Kang, Searles and Yuan, who carried out the work, said. “C3N bilayers with different twist angles could have completely different bandgaps, varying from 0.3 to 1.21 eV. To the best of our knowledge, this is the bilayer material that demonstrates the largest bandgap tuning range.”
“We found that the bandgaps of C3N bilayers can be tuned from 0.89 eV to nearly 0 eV only under a medium applied voltage of 1.91 V/nm,” Kang, Searles and Yuan said. “Overall, our results suggest that the C3N bilayer could substantially change the bandgap, while maintaining other attractive properties. The part of our team who focused on the experimental side of our research was able to synthesize the materials and test them experimentally.”
According to the researchers, the material could be used for both conducting and channel materials in transistor fabrication. This may be helpful in resolving the problems of contact resistance of different materials in transistor fabrication.
“The excellent photo-responsivity of AB’ C3N bilayers to near-infrared light makes them suitable for infrared photodetection, which has the advantages of an atmospheric window and 24-hour detection in comparison with other photodetection methods. In addition to a high carrier mobility, good photo-responsivity, stable chemical properties, low resistivity, and high mechanical strength, our C3N material is compatible with the well-developed silicon devices.”
“Considering that the development of current infrared photodetectors is hampered by the need for high-performance materials, C3N materials provide a promising option for future infrared photodetector and laser communications,” Kang, Searles and Yuan said. “Our future research in this field will focus on the application of C3N materials in infrared photodetection, sensor and ferroelectric materials. We will also try to fabricate a C3N transistor with high performance.”