Granted Patent B2

US 12,366,692 · App. 18/349,404 · Granted Jul 22, 2025

Inventors: Georg J. Ockenfuss (Santa Rosa, CA); Tim Gustafson (Santa Rosa, CA); Jeffrey James Kuna (San Francisco, CA); Markus Bilger (Santa Rosa, CA); Richard A. Bradley, Jr. (Santa Rosa, CA)

Assignee: VIAVI Solutions Inc.

G02B5/285G02B1/10G02B5/281G02B5/283H10F39/024H10F39/8053

Abstract

Claims (43)

1. A method comprising:

forming a photoresist layer on a surface of a substrate;

forming, in the photoresist layer and using a development time of 80 seconds to 100 seconds, an overhang by patterning the photoresist layer in a manner that uncovers a region,

wherein a length of the overhang, in a direction parallel to the surface of the substrate, is greater than 4 um; and

lifting the photoresist layer in a manner that provides a clean lift-off of the photoresist layer without breaking a coating that covers the overhang.

2. The method of claim 1 , wherein the length of the overhang is about 6 μm.

3. The method of claim 1 , wherein the photoresist layer includes a bottom release layer.

4. The method of claim 3 , wherein a thickness of the bottom release layer is greater than 2 μm.

5. The method of claim 3 , wherein a thickness of the coating is about 30% of a thickness of the bottom release layer.

6. The method of claim 3 , wherein a thickness of the bottom release layer is about 2.6 μm.

7. The method of claim 1 , wherein the photoresist layer includes a top photosensitive layer.

8. The method of claim 7 , wherein a thickness of the top photosensitive layer is about 2 μm.

9. The method of claim 1 , wherein a thickness of the coating is about 500 nm.

10. The method of claim 1 , wherein one or more sides of an optical filter under the overhang are sloped at an angle of about 5 degrees.

11. The method of claim 1 , further comprises:

forming an optical filter on the surface of the substrate after forming the overhang.

12. A method comprising:

forming a photoresist layer on a surface of a substrate;

forming, in the photoresist layer, an overhang with a length of about 6 μm in a direction parallel to the surface of the substrate; and

lifting the photoresist layer in a manner that provides a clean lift-off of the photoresist layer without breaking a coating that covers the overhang.

13. The method of claim 12 , wherein the overhang is formed using a development time of 80 seconds to 100 seconds.

14. The method of claim 12 ,

wherein the photoresist layer includes a bottom release layer,

wherein a thickness of the bottom release layer is greater than 2 μm, and

wherein the overhang is greater than 4 μm.

15. The method of claim 12 ,

wherein the photoresist layer includes a bottom release layer, and

wherein a thickness of the coating is about 30% of a thickness of the bottom release layer.

16. The method of claim 12 ,

wherein the photoresist layer includes a bottom release layer and a top photosensitive layer,

wherein a thickness of the bottom release layer is about 2.6 μm,

wherein a thickness of the top photosensitive layer is about 2 μm, and

wherein a thickness of the coating is about 500 nm.

17. An optical filter, comprising:

a substrate;

an overhang over a surface of the substrate with a length of about 6 μm in a direction parallel to the surface of the substrate; and

a coating that covers the overhang,

a thickness of the coating being configured to ensure a clean lift-off of a photoresist layer without breaking the coating.

18. The optical filter of claim 17 , further comprising:

one or more metal layers; and

a top dielectric layer that extends over and protectively covers one or more portions of the one or more metal layers.

19. The optical filter of claim 18 , wherein the one or more portions of the one or more metal layers are tapered edges of the one or more metal layers.

20. The optical filter of claim 17 , wherein one or more sides of the optical filter under the overhang are sloped at an angle of about 5 degrees.

Assignments (5)

Continuity (5)

References Cited (175)