Nanodevices and nanostructures: quantum wires and quantum dots

ECE 423 Final ProjectWan-Ching Hung

Dec 12,2006

Quantum Dots and Quantum Lines A quantum dot typically contains between

1 to 200 atoms in diameter and its length, width, and high are generally defined less than 100nm.

The electron is retrained by Fermi wavelength.

Quantum dot is confined in 3 dimensions and quantum line is confined in 2 dimensions.

Quantum Dots Applications Si single electron tr

ansistors

Quantum Computer

Quantum Dots Applications

Nanobarcodes nanobarcodes are made

different quantum wires of different metals that have different

reflectivity.

Molecule capsule in drug delivery system

Quantum Confinement Under 100nm, the

wave property of electron can not be ignored.

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Tunneling Effect

Coulomb Blockade a Coulomb

blockade is the increased resistance at small bias voltage of an electronic device comprising at lease one low-capacitance tunnel junction.

Bottom-Up

Self Assembly

Applicatoins: solar cell, light-emitting diodes, capsule in drug delivery system

Chemical Colloidal Method

Lithography and Etching

Lithography: electron beam, ion beam, nanoimprint, dip pen nanolithography

Etching: wet etching, dry etching, plasma, implantation, photo etching

Split-gate Approach

Use additional voltage to create 2 dimensional confinements to control the shape and size of the quantum dot’s gate.

It’s a combination of e beam lithography, evaporation, lift off, contact annealing