Method of integrating epitaxial film onto assembly substrate
A method of growing an epitaxial film and transferring it to an assembly substrate is disclosed. The film growth and transfer are made using an epitaxy lateral overgrowth technique. The formed epitaxial film on an assembly substrate can be further processed to form devices such as solar cell, light emitting diode, and other devices and assembled into higher integration of desired applications.
1. A method of forming an epitaxial thin film layer comprising the steps:
providing an assembly substrate comprised substantially of non-semiconductor material including a plurality of openings;
providing a crystalline substrate having a surface region exposed within said plurality of openings;
introducing a liquid phase epitaxial (LPE) material into said plurality of openings;
controlling a temperature of said LPE material so as to grow the thin film layer within said assembly substrate on said surface region of said crystalline substrate;
detaching said crystalline substrate using a chemical etchant.
2. The method of claim 1 , wherein said thin film epitaxial layer can be grown laterally across a top surface of said assembly substrate.
3. The method of claim 1 , further including a step: processing said assembly substrate and thin film epitaxial layer as an integrated epitaxial packaged structure within a semiconductor processing apparatus to form active devices on said assembly substrate and/or said thin film epitaxial layer.
4. The method of claim 1 wherein said thin film epitaxial layer includes a graded composition throughout a thickness direction of said assembly substrate.
5. The method of claim 1 wherein said liquid phase epitaxial material is adapted with thermal characteristics matching said assembly substrate.
6. The method of claim 1 , wherein said crystalline substrate is detached by a combination of shearing action and said chemical etchant.
7. The method of claim 1 further including a step: forming one or more second separate thin film epitaxial layers on said thin film epitaxial layer.
8. The method of claim 1 further including a step: forming one or more second separate assembly substrates on said thin film epitaxial layer.
9. The method of claim 8 wherein said one or more second separate thin film epitaxial layers and said thin film epitaxial layer include different dopant species.
10. The method of claim 1 wherein said thin film epitaxial layer has a multidimensional structure including lines and via interconnects.
11. The method of claim 1 , wherein said thin film epitaxial layer forms part of a p-n junction.
12. The method of claim 1 , wherein said thin film epitaxial layer forms part of an integrated circuit device.
13. The method of claim 1 further including a step of forming a sacrificial layer attached between a bottom surface of said assembly substrate and said surface of said crystalline substrate.
14. The method of claim 1 further including a step of forming a spacer situated adjacent said assembly substrate and above said crystalline substrate.
15. The method of claim 1 further including a step: controlling heating and cooling of said liquid phase material.
16. The method of claim 1 wherein said crystalline substrate can be re-used after said epitaxial layer is separated for growing a second epitaxial layer.
17. The method of claim 1 further including a step: controlling a side profile of said openings to be vertical, step recessed or sloped to any desired angle.
18. A method of forming an epitaxial thin film layer comprising the steps:
providing an assembly substrate comprised substantially of non-semiconductor material including a plurality of openings;
providing a crystalline substrate having a surface region exposed within said plurality of openings;
introducing a liquid phase epitaxial (LPE) material into said plurality of openings;
controlling a temperature of said LPE material so as to grow the thin film layer within said assembly substrate on said surface region of said crystalline substrate;
forming a sacrificial layer attached between a bottom surface of said assembly substrate and said surface of said crystalline substrate.
19. The method of claim 18 further including a step: processing said assembly substrate and thin film epitaxial layer as an integrated epitaxial packaged structure within a semiconductor processing apparatus to form active devices on said assembly substrate and/or said thin film epitaxial layer.
20. The method of claim 18 wherein said thin film epitaxial layer includes a graded composition throughout a thickness direction of said assembly substrate.
21. The method of claim 18 further including a step: forming one or more second separate assembly substrates on said thin film epitaxial layer.
22. The method of claim 18 wherein said thin film epitaxial layer has a multidimensional structure including lines and via interconnects.
23. The method of claim 18 , wherein said thin film epitaxial layer forms part of a p-n junction.
24. The method of claim 18 , wherein said thin film epitaxial layer forms part of an integrated circuit device.
25. The method of claim 18 wherein said crystalline substrate can be re-used after said epitaxial layer is separated for growing a second epitaxial layer.
26. The method of claim 18 further including a step: controlling a side profile of said openings to be vertical, step recessed or sloped to any desired angle.