Bulk nano-ribbon and/or nano-porous structures for thermoelectric devices and methods for making the same

1. A method for making a structure including nano-ribbons, the method comprising:

providing a semiconductor substrate including a first surface, the first surface including first portions and second portions;

forming one or more layers on the first portions of the first surface, the second portions of the first surface being exposed; and

etching the semiconductor substrate through the second portions of the first surface to form at least multiple nano-ribbons, each of the nano-ribbons corresponding to a first end and a second end, the first end and the second end being separated by a first distance of at least 100 μm, each of the nano-ribbons corresponding to a cross-sectional area associated with a ribbon thickness ranging from 5 nm to 500 nm, each of the nano-ribbons being separated from at least another nano-ribbon selected from the multiple nano-ribbons by a second distance ranging from 5 nm to 500 nm.

2. The method of claim 1 , and further comprising filling one or more separation regions between at least two of the multiple nano-ribbons with one or more fill materials.

3. The method of claim 2 wherein the semiconductor substrate includes one or more semiconductor materials different from the one or more fill materials.

4. The method of claim 1 , and further comprising roughening sidewalls of the multiple nano-ribbons respectively.

5. The method of claim 1 , and further comprising forming multiple nanoholes in corresponding sidewalls through the multiple nano-ribbons respectively.

6. The method of claim 1 , and further comprising:

roughening sidewalls of the multiple nano-ribbons respectively; and

forming multiple nanoholes in the roughened sidewalls through the multiple nano-ribbons respectively.

7. The method of claim 1 wherein the process for etching the semiconductor substrate through the second portions of the first surface includes a wet etching process through the second portions of the first surface.

8. The method of claim 7 wherein the wet etching process includes an electroless chemical etching process.

9. The method of claim 7 wherein the wet etching process includes an electrolytic chemical etching process.

10. A method for making a structure including one or more nano-ribbons, the method comprising:

providing a semiconductor substrate including a first surface, the first surface including first portions and second portions;

forming one or more layers on the first portions of the first surface, the second portions of the first surface being exposed; and

etching the semiconductor substrate through the second portions of the first surface to form at least one nano-ribbon including multiple nano-ribbon parts, each of the nano-ribbon parts corresponding to a first end and a second end, the first end and the second end being separated by a first distance of at least 100 μm, each of the nano-ribbon parts corresponding to a cross- sectional area associated with a thickness ranging from 5 nm to 500 nm, each of the nano-ribbon parts being separated from at least another nano-ribbon part selected from the multiple nano-ribbon parts by a second distance ranging from 5 nm to 500 nm.

11. The method of claim 10 , and further comprising filling one or more separation regions between at least two of the multiple nano-ribbon parts with one or more fill materials.

12. The method of claim 11 wherein the semiconductor substrate includes one or more semiconductor materials different from the one or more fill materials.

13. The method of claim 10 , and further comprising roughening sidewalls of the multiple nano-ribbon parts respectively.

14. The method of claim 10 , and further comprising forming multiple nanoholes in corresponding sidewalls through the multiple nano-ribbon parts respectively.

15. The method of claim 10 , and further comprising:

roughening sidewalls of the multiple nano-ribbon parts respectively; and

forming multiple nanoholes in the roughened sidewalls through the multiple nano-ribbon parts respectively.

16. The method of claim 10 wherein the process for etching the semiconductor substrate through the second portions of the first surface includes a wet etching process through the second portions of the first surface.

17. The method of claim 16 wherein the wet etching process includes an electroless chemical etching process.

18. The method of claim 16 wherein the wet etching process includes an electrolytic chemical etching process.

19. A method for making a porous structure, the method comprising:

providing a nonporous semiconductor substrate including one or more surfaces, the one or more surfaces including first portions and second portions;

forming one or more layers on the first portions of the one or more surfaces, the second portions of the one or more surfaces being exposed; and

etching the nonporous semiconductor substrate through the second portions of the one or more surfaces to form a porous semiconductor substrate including multiple first voids connected with each other, each of the multiple first voids corresponding to a first cross-sectional area associated with a first distance across ranging from 5 nm to 500 nm, each of the multiple first voids being separated from at least another void by a first distance ranging from 5 nm to 500 nm.

20. The method of claim 19 , and further comprising filling the multiple first voids with one or more fill materials.

21. The method of claim 20 wherein the nonporous semiconductor substrate includes one or more semiconductor materials different from the one or more fill materials.

22. The method of claim 19 , and further comprising roughening sidewalls of at least some of the multiple first voids.

23. The method of claim 19 wherein the process for etching the nonporous semiconductor substrate through the second portions of the one or more surfaces is performed to form the porous semiconductor substrate, at least one of the multiple first voids being completely surrounded by one or more solid materials of the porous semiconductor substrate.

24. The method of claim 19 wherein the process for etching the nonporous semiconductor substrate through the second portions of the one or more surfaces is performed to fowl the porous semiconductor substrate, at least one of the multiple first voids being open to an area outside the porous semiconductor substrate.

25. The method of claim 19 wherein the process for etching the nonporous semiconductor substrate through the second portions of the one or more surfaces is performed to form the porous semiconductor substrate further including one or more second voids, each of the one or more second voids not being connected with any void, each of the one or more second voids corresponding to a second cross-sectional area associated with a second distance across ranging from 5 nm to 500 nm, each of the one or more second voids being separated from at least another void by a second distance ranging from 5 nm to 500 nm.

26. The method of claim 25 , and further comprising filling the one or more second voids with one or more fill materials.

27. The method of claim 26 wherein the nonporous semiconductor substrate includes one or more semiconductor materials different from the one or more fill materials.

28. The method of claim 25 , and further comprising roughening sidewalls of at least some of the one or more second voids.

29. The method of claim 19 wherein the process for etching the nonporous semiconductor substrate through the second portions of the one or more surfaces includes a wet etching process through the second portions of the one or more surfaces.

30. The method of claim 19 wherein the wet etching process includes an electroless chemical etching process.

31. The method of claim 19 wherein the wet etching process includes an electrolytic chemical etching process.