Method for forming a MEMS

1. A method for forming a MEMS, comprising:

bonding a first surface of a layer of piezoelectric material to a transfer substrate, wherein the transfer substrate has a surface roughness less than about 50 Angstroms;

polishing an exposed surface of the piezoelectric material, on an opposite side of the layer from the first surface to form a polished surface; and

bonding the polished surface to a MEMS body.

2. The method of claim 1 , wherein bonding a first surface of a layer of piezoelectric material to a transfer substrate includes adhering the first surface to the transfer substrate with a resin.

3. The method of claim 1 , wherein bonding the polished surface to a MEMS body includes adhering the polished surface to the MEMS body with a resin.

4. The method of claim 1 , wherein the polishing is chemical mechanical polishing.

5. The method of claim 1 , wherein the transfer substrate has a surface roughness of between about 1 and 10 Angstroms.

6. The method of claim 1 , wherein the polished surface has a surface roughness of between about 10 and 20 Angstroms.

7. The method of claim 1 , further comprising forming a conductive layer on the polished surface.

8. The method of claim 1 , further comprising cutting the piezoelectric material prior to bonding the polished surface to the MEMS body.

9. The method of claim 1 , further comprising grinding away part of the piezoelectric material prior to polishing.

10. The method of claim 1 , further comprising grinding away the transfer substrate.

11. The method of claim 10 , further comprising polishing away the transfer substrate.

12. The method of claim 10 , further comprising polishing a surface of the piezoelectric material that is opposite to the polished surface.

13. The method of claim 1 , further comprising forming a conductive layer on a surface of the piezoelectric material that is opposite to the polished surface.

14. The method of claim 1 , wherein polishing the exposed surface includes polishing away at least about 4 microns from the piezoelectric material to remove damage.

15. The method of claim 1 , wherein polishing the exposed surface includes polishing away between about 4 and 10 microns from the piezoelectric material to remove damage.

16. A method for forming a MEMS, comprising:

polishing a block of piezoelectric material to form a flat surface;

applying a conductive layer on the flat surface;

bonding the conductive layer to a transfer substrate, leaving a surface opposed to the flat surface exposed, wherein the transfer substrate has a surface roughness less than about 50 Angstroms;

after bonding the conductive layer to the transfer substrate, thinning the block of piezoelectric material;

polishing the surface opposed to the flat surface;

after polishing the surface opposed to the flat surface, bonding the piezoelectric material to a body having chambers formed therein; and

removing the transfer substrate.

17. A method for forming a MEMS, comprising:

bonding a first surface of a layer of piezoelectric material to a transfer substrate;

polishing an exposed surface of the piezoelectric material, on an opposite side of the layer from the first surface to form a polished surface;

bonding the polished surface to a MEMS body; and

cutting the piezoelectric material prior to bonding the polished surface to the MEMS body.

18. The method of claim 17 , wherein cutting the piezoelectric material further comprises cutting into the transfer substrate.

19. A method for forming a MEMS, comprising:

bonding a first surface of a layer of bulk piezoelectric material to a transfer substrate;

reducing a thickness of the layer of the bulk piezoelectric material to less than 20 microns;

polishing an exposed surface of the piezoelectric material, on an opposite side of the layer from the first surface to form a polished surface; and

bonding the polished surface to a MEMS body.