Mass production of micro-optical devices, corresponding tools, and resultant structures
View Patent ↗A micro-optical element includes a support substrate, a micro-optical lens in a cured replication material on a first surface of the support substrate, and an opaque material aligned with and overlapping the micro-optical lens along a vertical direction.
1. A method of forming a micro-optical lens, the method comprising: providing a replication material between a support substrate and a master substrate, the master substrate having a first surface including a micro-optical lens mold and at least one trench spaced apart from and surrounding the micro-optical lens mold therein, the micro-optical lens mold and the trench being completely separated from each other; planarizing the replication material; bringing the support substrate towards the first surface of the master substrate; and curing the replication material to form a replica including a lens.
2. The method as claimed in claim 1 , wherein:
planarizing includes application of a heated flat element to the replication material; and
curing includes hardening of the planarized replication material.
3. The method as claimed in claim 1 , further comprising etching the replica into the support substrate.
4. The method as claimed in claim 1 , wherein curing the replication material includes forming a standoff surrounding the lens.
5. The method as claimed in claim 1 , wherein, during curing, light is prevented from being incident on the replication material in the trench.
6. The method as claimed in claim 5 , further comprising, after curing:
removing the master substrate; and
removing uncured replication material from the support substrate.
7. The method as claimed in claim 1 , wherein the master substrate is part of a master wafer.
8. The method as claimed in claim 1 , wherein the micro-optical lens mold is a concave micro-optical lens mold.
9. The method as claimed in claim 8 , further comprising removing at least a portion of the replication material from the support substrate, such that at least a portion of the replication material remains within the concave micro-optical lens mold of the master substrate.
10. The method as claimed in claim 8 , wherein providing the replication material includes overfilling the concave micro-optical lens mold.
11. The method as claimed in claim 10 , wherein, during planarizing, the trench is filled with the replication material.
12. The method as claimed in claim 11 , wherein planarizing includes bringing a planar surface into contact with the replication material overfilling the concave micro-optical lens mold.
13. The method as claimed in claim 12 , wherein the planar surface is part of the support substrate.
14. The method as claimed in claim 1 , wherein providing the master substrate with the micro-optical lens mold and trench includes forming the trench a predetermined distance away from the micro-optical lens mold, such that a portion of a flat surface of the master substrate is between and separates the micro-optical lens mold and the trench.
15. The method as claimed in claim 4 , wherein curing the replication material includes forming the standoff to be spaced apart from the lens, such that the standoff and the lens are completely separated from each other.
16. A method of making a micro-optical device, comprising:
providing a replication material between a support substrate and a first surface of a master substrate having structural features for forming a micro-optical lens, at least one of the support substrate and the master substrate having a mask;
applying pressure to at least one of the support substrate and the master substrate;
curing the replication material to form a replica including the micro-optical lens and a standoff surrounding the micro-optical lens, curing including providing light through the surface having the mask; and
removing the support substrate including the replica,
wherein the mask corresponds a region surrounding the micro-optical lens between the micro-optical lens and the standoff.
17. The method as claimed in claim 16 , wherein the curing includes providing light through the master substrate.
18. The method as claimed in claim 17 , wherein the master substrate includes one or more of PDMS and PTFE.
19. The method as claimed in claim 16 , further comprising removing any replication material not cured during the curing.
20. The method as claimed in claim 16 , wherein the curing includes providing light through the support substrate.
21. The method as claimed in claim 20 , wherein the replica including the micro-optical lens is formed to overlap the mask, the mask including an opaque material.
22. The method as claimed in claim 16 , wherein the mask is on a surface opposite that contacting the replication material.
23. The method as claimed in claim 16 , wherein the mask is on a surface of the support substrate contacting the replication material.
24. The method as claimed in claim 16 , wherein curing the replication material to form the replica including the micro-optical lens and the standoff includes forming a space between the micro-optical lens and the standoff.
25. The method as claimed in claim 24 , wherein providing at least one of the support substrate and the master substrate with the mask includes positioning the mask to overlap a region of the space between the micro-optical lens and the standoff.
26. The method as claimed in claim 16 , wherein curing the replication material to form the replica including the micro-optical lens and the standoff includes forming cured micro-optical lens and standoff.
27. The method as claimed in claim 26 , wherein curing the replication material to form the replica including the micro-optical lens and the standoff includes forming the cured standoff with a substantially flat surface facing the master substrate.