Dual-modulated transistor
Researchers from Daegu Gyeongbuk Institute of Science and Technology (DGIST) and University of Cambridge designed dual-modulated vertically stacked transistors in which two gates, positioned above and below in a sandwich-like structure, control the channel through different mechanisms.
The lower electrode contains microscopic openings to allow electric signals to penetrate deeper into the channel interior, while the upper electrode is made from graphene to enable precise control of current flow. A blocking layer was also used in regions prone to current leakage.
“This research presents a new dual-gate design strategy that enables stable operation even in nanoscale channels,” said Jae Eun Jang, a professor in the Department of Electrical Engineering and Computer Science at DGIST, in a statement. “By overcoming the fundamental limitations of conventional vertical transistors, the technology is expected to serve as an important solution for accelerating the era of next-generation low-power, highly integrated 3D semiconductors.”
Since the approach doesn’t require ultra-precise alignment or high temperatures, the researchers believe it can be scaled to large-area or multilayer stacked structures. [1]
Graphene FET biosensors
Researchers at Penn State designed graphene FETs for biosensors that perform well in liquid-rich environments, with improved sensitivity and reduced signal drift compared with comparable transistor designs.
“We adjusted the design to have two gates rather than one, allowing us to have independent control over the amount of current flowing through the system,” said Vinay Kammarchedu, an electrical engineering doctoral candidate at Penn State, in a press release. “Using two gates, we can keep the current running through the system constant, removing a primary cause of signal drift. On top of that, we added a feedback system to one of the gates to more accurately track the impact that molecules have on the sensor’s voltage.”
The top gate has 10 times the capacitance of the bottom gate, which amplifies signals coming through the transistor and increases the sensor’s overall responsiveness. “If there is a tiny chemical change in the charge at the sensor’s surface, we see it multiplied by 10 in our measurements due to this feedback system. This allows us to clearly see very minor changes in chemical readings,” Kammarchedu added. “We can integrate up to 32 sensors and measure each one independently without electrical interference. By stacking arrays of these circuit boards together, we can scale up the number of sensors in a system, all while keeping the sensors themselves very small.”
The team is optimizing the sensors to identify volatile organic compounds associated with Parkinson’s disease and will continue to develop the sensing architecture for commercial use. [2]
More robust printed transistors
Researchers at Argonne National Laboratory and Brookhaven National Laboratory are working to improve aerosol jet printing and ink formulations to make longer-lasting, low-power flexible printed electronics.
The ink is based on vanadium dioxide, and redox gating is used to control the flow of electricity. In tests, the printed transistors operated at voltages as low as 0.4 to 0.5 volts and kept working for more than 6,000 on-off cycles. The switches could change states in about one second.
“Redox gating is robust and does not damage the materials, so we can run thousands of cycles without issues. In previous methods, devices could only run a few times — sometimes just 10 cycles — before failing. Our devices can run thousands of cycles with no problem,” said Wei Chen, a chemist from Argonne and the University of Chicago, in a statement. “From my perspective, the next step is logic devices. We’ve been in contact with industry partners interested in testing our devices for logic applications.” [3]
References
[1] G. Pyo, S. J. Heo, J. Jang, et al. “Dual-Modulated Vertically Stacked Transistors With Fully Laminated Plate-Type Architecture Featuring Nanoscale Channel Length.” Advanced Science (2026): e19410. https://doi.org/10.1002/advs.202519410
[2] V. Kammarchedu, H. Asgharian, H. Chenani, A. Ebrahimi. Active dual-gated graphene transistors for low-noise, drift-stable, and tunable chemical sensing. npj 2D Mater Appl (2026). https://doi.org/10.1038/s41699-026-00674-5
[3] A. J. Erwin, S. Hu, H. Zhou, et al. “Tunable 3D Aerosol Jet Printing of Low-Power Redox-Gated Transistors with Multicomponent Inks.” Adv. Mater. Technol.10, no. 19 (2025): e00648. https://doi.org/10.1002/admt.202500648
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AI Brief
Dual-modulated transistor; graphene FET biosensors; more robust printed transistors.
Dual-modulated transistor
Researchers from Daegu Gyeongbuk Institute of Science and Technology (DGIST) and University of Cambridge designed dual-modulated vertically stacked transistors in which two gates, positioned above and below in a sandwich-like structure, control the channel through different mechanisms.
The lower electrode contains microscopic openings to allow electric signals to penetrate deeper into the channel interior, while the upper electrode is made from graphene to enable precise control of current flow. A blocking layer was also used in regions prone to current leakage.
“This research presents a new dual-gate design strategy that enables stable operation even in nanoscale channels,” said Jae Eun Jang, a professor in the Department of Electrical Engineering and Computer Science at DGIST, in a statement. “By overcoming the fundamental limitations of conventional vertical transistors, the technology is expected to serve as an important solution for accelerating the era of next-generation low-power, highly integrated 3D semiconductors.”
Since the approach doesn’t require ultra-precise alignment or high temperatures, the researchers believe it can be scaled to large-area or multilayer stacked structures. [1]
Graphene FET biosensors
Researchers at Penn State designed graphene FETs for biosensors that perform well in liquid-rich environments, with improved sensitivity and reduced signal drift compared with comparable transistor designs.
“We adjusted the design to have two gates rather than one, allowing us to have independent control over the amount of current flowing through the system,” said Vinay Kammarchedu, an electrical engineering doctoral candidate at Penn State, in a press release. “Using two gates, we can keep the current running through the system constant, removing a primary cause of signal drift. On top of that, we added a feedback system to one of the gates to more accurately track the impact that molecules have on the sensor’s voltage.”
The top gate has 10 times the capacitance of the bottom gate, which amplifies signals coming through the transistor and increases the sensor’s overall responsiveness. “If there is a tiny chemical change in the charge at the sensor’s surface, we see it multiplied by 10 in our measurements due to this feedback system. This allows us to clearly see very minor changes in chemical readings,” Kammarchedu added. “We can integrate up to 32 sensors and measure each one independently without electrical interference. By stacking arrays of these circuit boards together, we can scale up the number of sensors in a system, all while keeping the sensors themselves very small.”
The team is optimizing the sensors to identify volatile organic compounds associated with Parkinson’s disease and will continue to develop the sensing architecture for commercial use. [2]
More robust printed transistors
Researchers at Argonne National Laboratory and Brookhaven National Laboratory are working to improve aerosol jet printing and ink formulations to make longer-lasting, low-power flexible printed electronics.
The ink is based on vanadium dioxide, and redox gating is used to control the flow of electricity. In tests, the printed transistors operated at voltages as low as 0.4 to 0.5 volts and kept working for more than 6,000 on-off cycles. The switches could change states in about one second.
“Redox gating is robust and does not damage the materials, so we can run thousands of cycles without issues. In previous methods, devices could only run a few times — sometimes just 10 cycles — before failing. Our devices can run thousands of cycles with no problem,” said Wei Chen, a chemist from Argonne and the University of Chicago, in a statement. “From my perspective, the next step is logic devices. We’ve been in contact with industry partners interested in testing our devices for logic applications.” [3]
References
[1] G. Pyo, S. J. Heo, J. Jang, et al. “Dual-Modulated Vertically Stacked Transistors With Fully Laminated Plate-Type Architecture Featuring Nanoscale Channel Length.” Advanced Science (2026): e19410. https://doi.org/10.1002/advs.202519410
[2] V. Kammarchedu, H. Asgharian, H. Chenani, A. Ebrahimi. Active dual-gated graphene transistors for low-noise, drift-stable, and tunable chemical sensing. npj 2D Mater Appl (2026). https://doi.org/10.1038/s41699-026-00674-5
[3] A. J. Erwin, S. Hu, H. Zhou, et al. “Tunable 3D Aerosol Jet Printing of Low-Power Redox-Gated Transistors with Multicomponent Inks.” Adv. Mater. Technol.10, no. 19 (2025): e00648. https://doi.org/10.1002/admt.202500648
Jesse Allen (all posts)
Jesse Allen is the Knowledge Center administrator and a senior editor at Semiconductor Engineering.