Band Gap Engineering

Properties of group IV elements and group III-V compounds:

Atomic structure:

Periodic table (interactive form)

Crystal structure -- the diamond covalent structure:

Interactive diamond and zincblende structures ( GaAs, Si, etc.)  The unit cell with lists of material property.  The applet shows a 3D view of the until and a 3D view of the covalent bonds.

Details of the tetrahedral covalent bonds in the diamond structure

The "Rosette Stone" of Bandgap Engineering

Energy gap versus lattice constant for the most common III-V ternary alloys. (Source) Other Rosette Stones: global and GaAlInN

MBE (Molecular Beam Epitaxy) -- The Pioneering Exploratory Methodology
(Click to see full size pictures)

	(Source)

 
Characteristics Direct and Indirect Bandgap Types
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GaAs   See also Direct Bandgap AlGaAs

Silicon See also Indirect Bandgap AlGaAs

To study bandgap variations in more detail go to the applets : GaAs-AlAs compositional variation and Si-Ge compositional variation

Characteristic Absorption (k) Index (n) Spectra
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Silicon	GaAs
AlAs	InP

Compositional variation of bandgap and index in Al_x Ga_1-x As

Heterostructures - Issue of Band Offsets

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See Winston Chan's (University of Iowa) wonderful applet Band Diagrams for Semiconductor Heterostructures (local copy)

Quantum Well (QW) Structure
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Reference: Quantum Well Structures and the Quantum Well Lasers

http://www.physik.uni-stuttgart.de/ExPhys/4.Phys.Inst./Optoelektronik/papers/icps94/node1.html
http://h50.iue.tuwien.ac.at:8001/vistaa19/node1.html
http://eesun.ece.utep.edu/courses/ee3329/ee3329/Studyguide/ToC/Fundamentals/index.html
http://ncce-src.ceg.uiuc.edu/tutorials/bte_dd/html/bte_dd.html
http://schof.Colorado.EDU/~bart/book/welcome.htm
 
 
 

A veritable "gold mine" of relevant semiconductor properties can be found at:   ®     Electronic archive: New Semiconductor Materials. Characteristics and Properties

Introduction Equivalents of length, area, mass, pressure, energy ... Physical Properties of Materials Basic parameters. Band, optical, electrical, mechanical, thermal and other properties. n, k database n, k for A3B5, A2B6, Metals, Oxides, Silicides and other materials. Auger recombination Theoretical models and calculation of Auger recombination coefficient.  Calculation of ground energy of electron and hole in In1-xGaxAsyP1-y