How do you make quantum dots?

Whatever the growth technique, the creation of a semiconductor heterostructure implicitly involves depositing material A on material B, with different electronic properties and different lattice parameters. The difference in lattice parameter implies the accumulation of elastic energy in the deposited material, directly proportional to the thickness of the layer. This amount of stored elastic energy cannot grow indefinitely, and figure 3 illustrates the two cases most commonly observed in the case of semiconductor heterostructures: beyond a certain critical thickness, h _c , the material must relax its elastic...