CNTFET is a type of field effect transistor that uses a carbon nanotube as the channel material. Carbon nanotubes have excellent mechanical and electrical properties and allow for 1-D ballistic electron transport. A single-walled carbon nanotube is used as the channel between source and drain contacts in a CNTFET. The gate contact wraps around the carbon nanotube channel, allowing for good electrostatic control of carriers. CNTFETs were first fabricated in 1998 and have properties like high drive current, transconductance, and temperature resilience making them promising for high frequency applications.

1. CNTFET
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2. CNTFET
• CNT is a cylindrical shaped nanostructure,
made of allotropes of carbon.
• Bonding between the atom is very strong.
• Diameter is in nano meter range.
• Depending on the diameter of he nano
tube,the intrinsic carrier concentration and
bandgap will vary.
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3. • Advantage of using CNTFET
• 1-D ballistic transport of electrons and holes
• High drive current and large transconductance
• High temperature resilience and strong
covalent bond.
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4. • Single wall CNT is used as the channel
between two electrodes which work as the
source and drain contacts of a FET., a CNTFET
can be fabricated.
• Gate contacts wraps all around the channel
(CNT), it has a very good control on carrier,
and allows for better electrostatics.
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5. Mr.B.Kannan, RIT 5

6. Types of carbon nano tubes.
• Single walled carbon nanotube.(SWCNT)
• Multi walled carbon Nanotube (MWCNT)
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7. CNTFET
• 1998-first cntfet was fabricated.
• Nano scale device that has excellent mechanical
and electrical properties.
• Constrcution and opeartion is simlar to MOSFET.
• In CNTFET-channel is formed by single
semicondcuting CNT.
• N-doped CNT is used as contact.
• Pottassium doped source and drain regions are
used to fabricate CNTFET.
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8. Structure.
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9. • Gate-control the current across the source and
drain terminal.
• Gate-on-current flow in thew channel
• MOSFET-channel made from lightly doped
silicon.
• CNTFET-channel is Carbon nano tubes.
• P-type and N-type CNTFET.-unipolar device
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10. DC-characteristics(p-type and n-type)
• Similar to MOSFET
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11. • Advantage and Application.
• Improved channel transport
• Switching speed increases and device gets
saturated faster.
• Reduces power consumption,high gain and
stable.
• Implanted in logic circuits.
• Operated in THz range.-high frequency regime.
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12. Types of CNTFET
• MOS-CNTFET
• SB-CNTFET
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13. SB-CNTFET
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15. Reference:
Yang, “Fundamentals of Semiconductor devices”, McGraw Hill International Edition,
1978.
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