Patent ID: 7618905

Claim:
A method for forming a heterostructure self-assembled quantum dot composed of multiple three-dimensionally confined regions comprising the steps of: providing a semiconductor substrate; first, depositing a first material on said semiconductor substrate nearly lattice matched to said semiconductor substrate; second, depositing a second material on said first material from said first step, said material highly strained relative to material from said first depositing step, thereby forming a self-assembled quantum dot; selecting a third material comprising the steps of: selecting a third material, different from said semiconductor substrate, strained in the same direction as said second material and having a smaller lattice constant difference relative thereto than a lattice constant difference relative to said first material; wherein said third material has a strain sufficient to inhibit subsequent growth except in regions over said self-assembled quantum dot and a bandstructure capable of confining electrons or holes relative to said self-assembled quantum dot; and third, depositing said third material on said self-assembled quantum dot said first and second material three-dimensionally confining electrons or holes and in intimate contact, structure-forming a heterostructure quantum dot.