Download - Single-electron Devices
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Agenda Milestone Motivations New characteristics Single-electron transistor (SET) Challenges Conclusions
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Milestone In 1909, Millikan first illustrated the
manipulation of single electrons. In 1985, Dmitri Averin & Konstantin
Likharev proposed single-electron transistor.
In 1987, Theodore Fulton & Gerald Doald at Bell lab fabricated and demonstrated SET.
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Motivation Power consumption challenges high
performance and high density chip design Faster and more information processing
resulting in generating more heat flux Reduce the corresponding charge per bit! Single-electron Device!!!
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SED new characteristics Exploit the quantum effect of tunneling
Control and measure the movement of single electron
Charge doest not flow continuously Instead in a quantized way
Extremely high charge sensitivity High precise for charge measurement
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Single-electron transistor (SET) Architecture Equivalent circuit Operation principle I-V curve SET VS. MOSFET
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Architecture
gateCg
Vg
Vb
Source Drain
Tunnel junctions
island
C1 C2
+q1 -q1 +q2 -q2
q
V2V1
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Equivalent circuit
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Operation principle
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Operation principle
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Operation principle
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I-V curve
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SET vs. MOSFET Structure
Two tunneling barrier vs. inversion channel Size
Extremely small vs. large (although scaled down) Main physical principle
Coulomb blockade vs. electron diffusion Threshold voltage & source-drain current
Periodic vs. not periodic Sensitivity
High vs. low (10000X) Power
Low vs. high
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SED challenges Difficult to precisely control the device
implementation Characteristic of the device varies
significantly from location to location Suffer from “offset charges”
Randomly fluctuation of control signal
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Conclusions Because of natural small dimension, SED is a
potential solution for continue silicon scaling. It is not clear that SET replaces FET. It is certain that quantum properties of electrons
will be crucial in the design of electron devices. Electron beam lithography and scanning probe
techniques offer the best prospects for the future. Some more esoteric techniques based on atomic
particle deposition and colloid chemistry may also provide some benefits.
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The End
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