Composition of, and method for forming, a semiconductor structure with multiple insulator coatings
Fabricating a semiconductor structure including forming a nanocrystalline core from a first semiconductor material, forming a nanocrystalline shell from a second, different, semiconductor material that at least partially surrounds the nanocrystalline core, wherein the nanocrystalline core and the nanocrystalline shell form a quantum dot. Fabrication further involves forming an insulator layer encapsulating the quantum dot to create a coated quantum dot, and forming an additional insulator layer on the coated quantum.
1. A method of fabricating a semiconductor structure, comprising:
forming a nanocrystalline core from a first semiconductor material;
forming at least one nanocrystalline shell from a second, different, semiconductor material that at least partially surrounds the nanocrystalline core, wherein the nanocrystalline core and the nanocrystalline shell(s) form a quantum dot;
forming an insulator layer encapsulating the quantum dot to create a coated quantum dot; and
forming at least one additional insulator layer on the coated quantum dot.
2. The method of claim 1 , further forming additional insulator layers encapsulating the quantum dot such that defects that may exist in each of the insulating layers are interrupted and do not channel continuously through the insulating layers.
3. The method of claim 1 , wherein forming the insulator layer encapsulating the quantum dot to create a coated quantum dot comprises forming a first metal oxide layer encapsulating the quantum dot.
4. The method of claim 3 , wherein forming the metal oxide layer encapsulating the quantum dot comprises selecting the metal oxide from a group of metal oxides consisting of silica (SiOx), titanium oxide (TiOx), zirconium oxide (ZrOx), alumina (AlOx), magnesium oxide (MgOx) and hafnia (HfOx).
5. The method of claim 2 , wherein forming additional insulator layers on the coated quantum dot provides for improved thermal stability, high temperature reliability, and/or high humidity reliability of the coated quantum dot.
6. The method of claim 5 , wherein forming the additional insulator layers on the coated quantum dot comprises forming organic layers and/or inorganic layers on the coated quantum dot.
7. The method of claim 6 , wherein forming organic layers comprises forming a layer of poly(p-xylylene) polymer.
8. The method of claim 6 , wherein forming inorganic layers comprises forming a layer with a compound or metal selected from a group of compounds and metals consisting of silica (SiOx), titanium oxide (TiOx), zirconium oxide (ZrOx), alumina (AlOx), magnesium oxide (MgOx) and hafnia (HfOx), and SiN x , copper, cobalt, and iron.
9. The method of claim 1 , wherein forming the insulator layer encapsulating the quantum dot to create a coated quantum dot comprises forming a first insulator layer encapsulating the quantum dot using a reverse micelle sol-gel reaction; and wherein forming the additional insulator layers on the coated quantum dot comprises forming an additional insulating layer encapsulating the quantum dot using a reverse micelle sol-gel process, a direct micelle sol-gel process, or a Stober sol-gel process.
10. The method of claim 1 , wherein, after forming the insulator layer encapsulating the quantum dot to create a coated quantum dot, and prior to forming the at least one additional insulator layer on the coated quantum dot, treating the coated quantum dot with a base or an acid.
11. The method of claim 1 , wherein, after forming the at least one additional insulator layer on the coated quantum dot, and prior to further forming additional insulator layers encapsulating the quantum dot, treating the coated quantum dot with a base or an acid.