Download - 8. Nano Devices
200 nm 1 nm 0.1 nm 0.1 nm (3D)
Superlattice
For an e at room temperature, 0.026 eVE kT
de Broglie wavelenth, 8 nm.2
h hp mE
If the layer thickness is comparable with then
quantum effects are important (quantum confinement).
HeterostructureIn some cases two different not only crystallize in the same manner but also have same lattice constants.
Both the materials grow together as a single crystal with two parts
The interface of these two materials in called a heterojuction
A heterojunction is an interface in a crystal of two different materials with the same lattice constant
When a heterojunction is repeated at regular intervals, we get the heterostructure.
Quantum structures and DOS
Applications are based on
1. Peculiar properties
Eg. Gold nanoparticles used as inorganic dye into glass and as low temperature catalyst
2. Huge surface area
Photoelectrochemical cells, sensors
3. Small size
Molecular Electronics and Nano electronics
Single molecules, Chem FET, ion selective FET (ISFET)
Nanobots
Nano medicine, nano robots
Biology
Nano biotech, DNA analysis
Catalysis by Gold nanoparticles in oxidation
Bandgap engineered quantum devices
Quantum well devices, quantum dot devices
Nanomechanics
Eg. Atomic Force Microscope (AFM)
Carbon nanotube emitters
Generates monochromatic electron beams of 7mm in diameter
Sensors, scanning probe tips, Li batteries
Photoelectrochemical Cells
High efficient conversion, large surface area
Photonic crystals and Plasmon waveguides
Waveguides and high-resolution spectral filters