WAFER-LEVEL OPTICAL STRUCTURE

• US 20200135788A1
• Filed: 10/24/2018
• Published: 04/30/2020
• Est. Priority Date: 10/24/2018
• Status: Active Grant

• Current Assignee: Himax Technologies Ltd. (Himax Technologies Incorporated)
• Original Assignee: Himax Technologies Ltd. (Himax Technologies Incorporated)
• Inventors: Chang, Chih-Sheng, Huang, Teng-Te, Hsu, Shu-Hao, Zhan, Jun-Yu
• Granted Patent: US 10,636,829 B1
• Time in Patent Office: Days
• CPC Class Codes: C09J 5/08 using foamed adhesives
• CPC Class Codes: H01L 27/14621 Colour filter arrangements
• CPC Class Codes: H01L 27/14627 Microlenses
• CPC Class Codes: H01L 27/14632 Wafer-level processed structures
• CPC Class Codes: H01L 27/14687 Wafer level processing
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof

Abstract

A wafer-level optical structure includes at least two optical lens sets disposed on an optically transparent wafer, at least one trench disposed between two adjacent optical lens sets to divide the two adjacent optical lens sets, at least one spacer disposed between two adjacent optical lens sets to be correspondingly and partially disposed in the trench, and an adhesive disposed inside the trench.

Claims

1. A wafer-level optical structure, comprising:

an optically transparent wafer;

at least two optical lens sets disposed on said optically transparent wafer, wherein each of said at least two optical lens sets comprising a lens integrated with a residual layer;

at least one trench disposed above said optically transparent wafer, wherein said at least one trenches is disposed between two adjacent said at least two optical lens sets to divide adjacent said at least two optical lens sets;

at least one spacer disposed on said optically transparent wafer, wherein said at least one spacer is disposed between adjacent said at least two optical lens sets to be correspondingly and partially disposed in one of said at least one trench; and

an adhesive disposed inside one of said at least one trench to at least partially fill the trench and in direct contact with one of said at least one spacer.

2. The wafer-level optical structure of claim 1, wherein each one of said at least two optical lens sets further comprises an extending shoulder and said extending shoulder is not in contact with adjacent said at least one spacer.

3. The wafer-level optical structure of claim 2, wherein two of adjacent said extending shoulders define one of said at least one trench.

4. The wafer-level optical structure of claim 2, wherein said adhesive is in direct contact with said extending shoulder.

5. The wafer-level optical structure of claim 1, wherein said adhesive is in direct contact with said optically transparent wafer.

6. The wafer-level optical structure of claim 1, further comprising:

a plurality of said trenches and said trenches having variable width.

7. The wafer-level optical structure of claim 1, further comprising:

an optically transparent substrate disposed on said at least one spacer.

8. The wafer-level optical structure of claim 7, wherein said optically transparent substrate is attached to said at least one spacer with the help of said adhesive.

9. The wafer-level optical structure of claim 7, further comprising:

at least two imaging optical lens sets disposed on said optically transparent substrate and respectively corresponding to said at least two optical lens sets.

10. The wafer-level optical structure of claim 1, further comprising:

at least two bottom optical lens sets disposed on said optically transparent wafer, located beneath said at least two optical lens sets and respectively corresponding to said at least two optical lens sets.

11. A method to form a wafer-level optical structure, comprising:

providing an optically transparent wafer with a residual layer disposed on said optically transparent wafer and having at least two lenses disposed on said residual layer, wherein each one of said at least two lenses is integrated with said residual layer;

partially removing said residual layer disposed between two adjacent said at least two lenses to form at least one trench and to form at least two optical lens sets, wherein each one of said at least two optical lens sets comprises said lens integrated with said residual layer;

filling said at least one trench with an adhesive material;

providing said at least one trench with a spacer so that said spacer is partially accommodated in said at least one trench to divide two of adjacent said at least two optical lens sets; and

performing a curing step to cure said adhesive material to become an adhesive.

12. The method to form a wafer-level optical structure of claim 11, wherein a laser treatment is used to remove said residual layer.

13. The method to form a wafer-level optical structure of claim 11, wherein said at least one trench exposes said optically transparent wafer.

14. The method to form a wafer-level optical structure of claim 11, wherein said adhesive is selected from a group consisting of a UV curable adhesive, a thermal curable adhesive and a pressure sensitive adhesive (PSA).

15. The method to form a wafer-level optical structure of claim 11, wherein removing said residual layer simultaneously forms an extending shoulder and said extending shoulder is attached to one of said at least two optical lens sets which is adjacent to said extending shoulder.

16. The method to form a wafer-level optical structure of claim 15, wherein said spacer is not in direct contact with said extending shoulder.

17. The method to form a wafer-level optical structure of claim 11, further comprising:

applying said adhesive material to a top surface of said spacer;

providing an optically transparent substrate to be disposed on said top surface of said spacer; and

performing a spacer curing step to cure said adhesive material disposed between said spacer and said optically transparent substrate to be said adhesive.

18. The method to form a wafer-level optical structure of claim 17, wherein there are at least two imaging optical lens sets disposed on said optically transparent substrate and respectively corresponding to said at least two optical lens sets.

19. The method to form a wafer-level optical structure of claim 11, wherein there are at least two bottom optical lens sets disposed on said optically transparent wafer, located beneath said at least two optical lens sets and respectively corresponding to said at least two optical lens sets.

20. A method to form a wafer-level optical structure, comprising:

providing an optically transparent wafer with a residual layer disposed on said optically transparent wafer and having at least two lenses disposed on said residual layer, wherein each one of said at least two lenses is integrated with said residual layer;

partially removing said residual layer disposed between two of adjacent said at least two lenses to form at least one trench and to form at least two optical lens sets, wherein each one of said at least two optical lens sets comprises one of said at least two lenses integrated with said residual layer;

filling said at least one trench with an adhesive material;

providing an optically transparent substrate with at least one spacer;

combining said optically transparent substrate with said optically transparent wafer so that said at least one spacer is in contact with said adhesive material, disposed between two adjacent said at least two optical lens sets and correspondingly and partially accommodated in said at least one trench to divide two adjacent said at least two optical lens sets; and

performing a curing step to cure said adhesive material to become an adhesive.