Related Experiment Video
Updated: May 25, 2026
09:20
Fabrication of Low Temperature Carbon Nanotube Vertical Interconnects Compatible with Semiconductor Technology
Published on: December 7, 2015
Variability in carbon nanotube transistors: improving device-to-device consistency
Aaron D Franklin1, George S Tulevski, Shu-Jen Han
1IBM T. J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, New York 10598, United States. aaronf@us.ibm.com
ACS Nano
|January 26, 2012
Summary
Researchers reduced variability in carbon nanotube transistors using a hydrophobic monolayer. This passivation technique significantly improves device consistency for digital applications.
Area of Science:
- Materials Science
- Nanotechnology
- Semiconductor Physics
Background:
- Carbon nanotube transistors exhibit significant hysteresis and threshold voltage variation, limiting their use in integrated circuits.
- Variability in carbon nanotube transistors is a major obstacle for their widespread adoption in digital electronics.
Purpose of the Study:
- To elucidate the origin of variability in carbon nanotube transistors.
- To develop a passivation strategy to improve device consistency.
Main Methods:
- Employed a top-coated, hydrophobic monolayer to passivate bottom-gated carbon nanotube field-effect transistors.
- Investigated the effect of passivating the nanotube channel versus only the supporting substrate.
- Analyzed the influence of gate and drain-source bias on hysteresis.
Main Results:
- Passivating the nanotube channel with a hydrophobic monolayer significantly reduced device-to-device variation.
- Hysteresis and threshold voltage variation were reduced by an average of 84% and 53%, respectively.
- Hysteresis showed a strong dependence on applied gate and drain-source bias.
Conclusions:
- A top-coated hydrophobic monolayer effectively mitigates variability in carbon nanotube transistors.
- Passivating the nanotube channel is crucial for improving device consistency.
- Understanding bias-dependent hysteresis is essential for evaluating passivation effectiveness.
Related Concept Videos
01:27Biasing of Metal-Semiconductor Junctions
Biasing metal-semiconductor junctions involves applying a voltage across the junction. Specifically, the metal is connected to a voltage source, while the semiconductor is grounded. This technique is essential for controlling the direction and magnitude of current flow in electronic devices, including diodes, transistors, and photovoltaic cells.
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
In Schottky junctions, where the semiconductor is n-type, applying a positive voltage to the metal relative to the semiconductor reduces its Fermi...
01:22Biasing of FET
Biasing a Junction Field Effect Transistor (JFET) is crucial for setting operational parameters and ensuring efficient functioning in electronic circuits. JFETs are characterized by using a single carrier type in N-channel or P-channel configurations, where the channel is surrounded by PN junctions. These junctions are central to the device's ability to control current flow.
In an N-channel JFET, the structure consists of N-type material forming the channel on a P-type substrate, with the gate...
In an N-channel JFET, the structure consists of N-type material forming the channel on a P-type substrate, with the gate...
01:17Characteristics of MOSFET
Metal-oxide-semiconductor field-effect Transistors, or MOSFETs, play a critical role in electronic circuits. They are primarily utilized for amplifying and switching signals.
Various vital parameters influence their functionality, which is crucial for theory and electronics applications. First, channel dimensions, precisely length, and width, are pivotal. The size of these channels affects the transistor's ability to carry current and switching speeds; shorter channels typically enable quicker...
Various vital parameters influence their functionality, which is crucial for theory and electronics applications. First, channel dimensions, precisely length, and width, are pivotal. The size of these channels affects the transistor's ability to carry current and switching speeds; shorter channels typically enable quicker...
00:51Non-ohmic Devices
In most substances, the current flow is proportional to the voltage applied to it. A simple relationship between the values of current, voltage, and resistance is known as Ohm's law. Nonohmic devices do not exhibit a linear relationship between voltage and current. One such device is the semiconducting circuit element known as a diode. A diode is a circuit device that allows current flow in only one direction.
Consider a simple circuit consisting of a battery, a diode, and a resistor. A diode...
Consider a simple circuit consisting of a battery, a diode, and a resistor. A diode...
01:21Characteristics of JFET
Junction Field Effect Transistors (JFETs) exhibit specific operational characteristics based on the relationship between the drain current (id) and the drain-source voltage (Vds), along with varying gate-source voltages (Vgs).
The core of a JFET's operation is controlling drain current by modulating the gate-source voltage. When the drain and gate voltage are set to zero, the JFET exhibits no net current flow, representing a state of equilibrium. The drain current increases linearly as the...
The core of a JFET's operation is controlling drain current by modulating the gate-source voltage. When the drain and gate voltage are set to zero, the JFET exhibits no net current flow, representing a state of equilibrium. The drain current increases linearly as the...
01:20Types of Semiconductors
Intrinsic semiconductors are highly pure materials with no impurities. At absolute zero, these semiconductors behave as perfect insulators because all the valence electrons are bound, and the conduction band is empty, disallowing electrical conduction. The Fermi level is a concept used to describe the probability of occupancy of energy levels by electrons at thermal equilibrium. In intrinsic semiconductors, the Fermi level is positioned at the midpoint of the energy gap at absolute zero. When...