5. BAND GAP ENGINEERING
Trends in cubic UC parameters and Eg
As a function of composition x for the solid solution ternary semiconductor AlxGa1-xAs
A solid solution implies a random distribution of Al and Ga in the zinc blende type lattice (isomorphous substitution)

6. BAND GAP ENGINEERING
The roughly linear dependence of the physical properties on composition is known as Vegard’s law and proves that the distribution of the Al and Ga is random
P(AlxGa1-xAs) = xP(AlAs) + (1-x)P(GaAs)
Any physical property is the atomic fraction weighted average of the two end members

7. BAND GAP ENGINEERING
Band gap engineering enables a range of designer optical and electronic devices to be fabricated