Method of forming a rare-earth dielectric layer
Methods for forming compositions comprising a single-phase rare-earth dielectric disposed on a substrate are disclosed. In some embodiments, the method forms a semiconductor-on-insulator structure. Compositions and structures that are formed via the method provide the basis for forming high-performance devices and circuits.
1. A method comprising forming a first dielectric layer on a substrate, wherein said first dielectric layer comprises a rare-earth metal, and wherein said first dielectric layer is alkaline earth metal-free, wherein said rare-earth metal forms a cation having a radius less than 0.93 angstroms, and further wherein said first dielectric layer has a single-phase crystal structure.
2. The method of claim 1 wherein said first dielectric layer is formed using atomic layer epitaxy.
3. The method of claim 1 further comprising forming a template layer on said substrate prior to forming said first dielectric layer, wherein said template layer provides an energetically-favorable surface for the bonding of one of either cations or anions.
4. The method of claim 1 further comprising forming a template layer on said substrate prior to forming said first dielectric layer, wherein said template layer changes a surface of said substrate from non-polar to polar.
5. The method of claim 1 further comprising forming a template layer on said substrate prior to forming said first dielectric layer, wherein said template layer comprises an anion-rich/cation-rich superlattice structure.
6. The method of claim 1 further comprising forming a template layer on said substrate prior to forming said first dielectric layer, wherein said template layer provides a means of ordering bixbyite oxygen vacancies in said first dielectric layer.
7. The method of claim 1 further comprising providing said substrate, wherein said substrate comprises a silicon wafer, and wherein said silicon wafer has a crystal orientation selected from the group consisting of <111>, <100>, and <011>.
8. The method of claim 7 further comprising providing said silicon wafer, wherein said silicon wafer is miscut from its crystal orientation by an angle that has a value within the range of 0 to 20 degrees.
9. The method of claim 1 further comprising forming a active layer, wherein said active layer has a substantially single-phase crystal structure, and wherein said active layer comprises a material selected from the group consisting of silicon, germanium, silicon-germanium, gallium arsenide, indium phosphide, and silicon carbide.
10. The method of claim 9 wherein said active layer is formed using atomic layer epitaxy.
11. The method of claim 9 further comprising forming a wetting layer for changing a surface of said first dielectric layer from polar to non-polar.
12. The method of claim 9 further comprising forming a wetting layer for providing a surface having surface energy greater than the sum of (1) the surface energy of said active layer, and (2) the interface energy, and wherein said wetting layer supports two-dimensional, layer-by-layer growth of said active layer.
13. The method of claim 9 further comprising forming a wetting layer comprising a material selected from the group consisting of ytterbium monoxide and erbium nitride.
14. The method of claim 9 further comprising forming a second dielectric layer, wherein said second dielectric layer comprises a rare-earth metal, and wherein said second dielectric layer has a substantially single-phase crystal structure, and further wherein said active layer is interposed between said first dielectric layer and said second dielectric layer.
15. The method of claim 14 further comprising forming a template layer on said active layer prior to forming said second dielectric layer, wherein said template layer supports formation of said second dielectric layer.
16. The method of claim 1 further comprising forming said first dielectric layer with a crystal structure that is bixbyite.
17. The method of claim 1 further comprising forming said first dielectric layer with a crystal structure that is one of oxygen-rich bixbyite and oxygen-poor bixbyite.
18. The method of claim 9 further comprising a second dielectric layer comprising a rare-earth metal, wherein the crystal structure of said second dielectric layer is substantially single-phase.
19. The method of claim 18 wherein said first dielectric layer, said active layer, and second dielectric layer are formed using atomic layer epitaxy.
20. The method of claim 1 further comprising forming a rare-earth nitride layer, wherein the crystal structure of said rare-earth nitride layer is substantially single-phase.
21. The method of claim 1 wherein said substrate comprises a material selected from the group consisting of silicon, germanium, silicon-germanium, gallium arsenide, indium phosphide, and silicon carbide.
22. The method of claim 1 wherein said rare-earth metal is selected from the group consisting of erbium, ytterbium, dysprosium, holmium, thulium, and lutetium.
23. A method comprising forming a first dielectric layer on a substrate, wherein said first dielectric layer comprises a rare-earth metal, and wherein said first dielectric layer is alkaline earth metal-free, and further wherein said rare-earth metal has an atomic number greater than or equal to 66, and further wherein the crystal structure of said first dielectric layer is single-phase.
24. The method of claim 23 further comprising forming said first dielectric layer with a crystal structure that is bixbyite.
25. The method of claim 23 further comprising forming said first dielectric layer with a crystal structure that is one of oxygen-rich bixbyite and oxygen-poor bixbyite.
26. The method of claim 23 further comprising forming said first dielectric layer such that said rare-earth metal is bonded in an ionization state that is triply ionized (3 + ).
27. The method of claim 23 further comprising forming an active layer, wherein the crystal structure of said active layer is single-phase, and wherein said active layer comprises a material selected from the group consisting of silicon, germanium, silicon-germanium, gallium arsenide, indium phosphide, and silicon carbide.
28. A method comprising forming a first dielectric layer on a substrate, wherein said first dielectric layer comprises a rare-earth metal, and wherein said first dielectric layer is alkaline earth metal-free, and wherein the crystal structure of said first dielectric layer is that of an oxygen-vacancy-derived fluorite crystal, and further wherein the crystal structure of said first dielectric layer is single-phase.
29. The method of claim 28 further comprising forming said first dielectric layer such that said first dielectric layer comprises oxygen vacancies that are aligned in the <111> crystal plane.
30. The method of claim 28 further comprising forming an active layer having a crystal structure that is single-phase, wherein said active layer comprises a material selected from the group consisting of silicon, germanium, silicon-germanium, gallium arsenide, indium phosphide, and silicon carbide.
31. A method comprising:
providing a substrate, wherein said substrate comprises a silicon wafer having crystal orientation that is selected from the group consisting of <001>, <111>, and <011>, and wherein said silicon wafer is miscut from its crystal orientation by an angle that has a value within the range of 0 to 20 degrees; and
forming a first dielectric layer, wherein said first dielectric layer comprises a dielectric comprising a rare-earth metal, and wherein said first dielectric layer is alkaline earth metal-free, and further wherein said first dielectric layer has a crystal structure that is that of an oxygen-vacancy-derived fluorite crystal.
32. The method of claim 31 further comprising forming a superlattice layer, wherein said superlattice layer is interposed between said substrate and said first dielectric layer.
33. The method of claim 31 further comprising forming an active layer having a crystal structure that is single-phase, wherein said active layer comprises a material selected from the group consisting of silicon, germanium, silicon-germanium, gallium arsenide, indium phosphide, and silicon carbide.
34. The method of claim 31 wherein said first dielectric layer and said semiconductor layer are formed using atomic layer epitaxy.
35. A method comprising:
providing a substrate having a first surface that is non-polar;
forming a template layer for providing a second surface that is polar, wherein said template layer is formed using an epitaxial growth method; and
forming a first dielectric layer, wherein said first dielectric layer comprises a rare-earth metal, and wherein said first dielectric layer is alkaline earth metal free, and further wherein said first dielectric layer has a single-phase crystal structure.
36. The method of claim 35 further comprising forming a wetting layer for providing a third surface that is non-polar, wherein said wetting layer is formed using an epitaxial growth method.
37. The method of claim 35 further comprising forming an active layer having a crystal structure that is single-phase, wherein said active layer comprises a material selected from the group consisting of silicon, germanium, silicon-germanium, gallium arsenide, indium phosphide, and silicon carbide.
38. The method of claim 37 wherein said template layer, said first dielectric layer, said wetting layer, and said active layer are formed using atomic layer epitaxy.