Granted Patent B2

US 12,399,340 · App. 17/975,451 · Granted Aug 26, 2025

Inventors: Frank Gütle (Stäfa, CH); Lukas Rüthemann (Stäfa, CH); Marcel Mittelmueller (Stäfa, CH)

Assignee: Sensirion AG

G02B7/02G02B6/4204H10H29/855G02B3/00G02B3/0006G02B3/0012

Abstract

Claims (55)

1. An optical component comprising:

a chip comprising a carrier substrate including a semiconductor material and a membrane directly disposed on an exterior planar membrane-carrying surface of the carrier substrate, the membrane formed integrally with the carrier substrate;

a cavity formed in the carrier substrate, the cavity including a first end and a second end, the membrane including a cavity-spanning portion that spans the cavity at its first end, the cavity-spanning portion of the membrane being transparent to light in a wavelength range of interest; and

at least one optical element formed on or in the cavity-spanning portion of the membrane, the at least one optical element to modify light,

wherein the optical component is only a passive component and does not include any complementary metal oxide semiconductor (CMOS) circuitry, and

wherein a height of the membrane is less than ten percent a height of the carrier substrate.

2. The optical component of claim 1 ,

wherein the planar membrane-carrying surface of the carrier substrate is laterally delimited by a perimeter,

wherein the membrane comprises at least one transparent membrane layer, and

wherein the at least one transparent membrane layer only partially laterally extends on the perimeter of the planar membrane-carrying surface of the carrier substrate, leaving a strip on the membrane-carrying surface along the perimeter of the at least one transparent membrane layer that lacks any transparent membrane material.

3. The optical component of claim 1 ,

wherein the membrane comprises at least one transparent membrane layer, and

wherein the optical component comprises an opaque layer that laterally covers a perimeter of the at least one transparent membrane layer to prevent light from entering or exiting the membrane at its perimeter.

4. The optical component of claim 3 , wherein the opaque layer includes a metal layer.

5. The optical component of claim 1 ,

wherein the membrane, at least in a region that laterally surrounds the cavity-spanning portion, comprises a layer stack comprising a plurality of transparent membrane layers separated by metal layers, and

wherein each of the transparent membrane layers has a thickness that is smaller than a wavelength of light for which the respective transparent membrane layer is transparent.

6. The optical component of claim 1 , wherein the carrier substrate forms a lateral perimeter wall that laterally delimits the cavity, the lateral perimeter wall having a lateral width of no more than 500 micrometers.

7. The optical component of claim 1 , wherein the carrier substrate is made of silicon.

8. The optical component of claim 1 , wherein the membrane comprises at least one membrane layer including a material selected from silicon oxide, silicon nitride, crystalline silicon, and amorphous silicon.

9. The optical component of claim 1 ,

wherein the chip is a silicon-on-insulator chip comprising the carrier substrate, the carrier substrate composed of silicon, an insulating layer on top of the carrier substrate and a silicon layer on top of the insulating layer, and

wherein the cavity-spanning portion of the membrane comprises the silicon layer.

10. The optical component of claim 9 , wherein the cavity extends through the carrier substrate and the insulating layer all the way to the silicon layer, such that the cavity-spanning portion of the membrane comprises the silicon layer but not the insulating layer.

11. The optical component of claim 9 , wherein the cavity extends through the carrier substrate up to the insulating layer such that the cavity-spanning portion of the membrane comprises both the silicon layer and the insulating layer.

12. The optical component of claim 1 , wherein the at least one optical element comprises an external optical element disposed on a surface of the cavity-spanning portion of the membrane that faces away from the cavity and/or on a surface of the cavity-spanning portion of the membrane that faces towards the cavity.

13. The optical component of claim 1 , wherein the at least one optical element comprises an internal optical element formed inside the cavity-spanning portion of the membrane, the internal optical element embedded within the membrane.

14. The optical component of claim 1 , wherein the at least one optical element comprises a surface structure formed in a surface of the cavity-spanning portion of the membrane that faces away from the cavity and/or in a surface of the cavity-spanning portion of the membrane that faces towards the cavity.

15. The optical component of claim 1 , wherein the at least one optical element comprises a focal element configured to concentrate light that impinges on the at least one optical element.

16. The optical component of claim 1 , wherein the at least one optical element comprises a diffusor configured to diffuse light that impinges on the at least one optical element.

17. The optical component of claim 1 , wherein the at least one optical element comprises a dielectric filter configured to selectively transmit or reject light in at least one predetermined wavelength range.

18. The optical component of claim 1 , wherein the at least one optical element comprises an opaque baffle having an opening that defines an aperture for light that enters or exits the cavity through the cavity-spanning portion of the membrane.

19. The optical component of claim 1 ,

wherein the carrier substrate has a constant or maximum carrier substrate thickness,

wherein the cavity-spanning portion of the membrane has a constant or maximum membrane thickness, and

wherein the constant or maximum membrane thickness is 10% or less of the constant or maximum carrier substrate thickness.

20. The optical component of claim 1 , wherein the cavity-spanning portion of the membrane has a thickness that is at most 20 micrometers.

21. The optical component of claim 1 , wherein the membrane is configured to be an etch stop to prevent further etching.

22. The optical component of claim 1 , wherein an upper surface of the membrane was formed by wafer deposition and a lower surface of the membrane was formed by etching, and wherein the upper surface is opposite of the lower surface.

23. The optical component of claim 1 , wherein a height of the membrane is between one to ten percent a height of the carrier substrate.

24. The optical component of claim 1 , wherein the optical element is on a surface of the membrane, wherein the surface is opposite another surface of the membrane.

25. The optical component of claim 1 , wherein the cavity was monolithically formed in the carrier substrate.

26. The optical component of claim 1 , wherein the wavelength range of interest includes between 400 nm to 1100 nm.

27. The optical component of claim 1 , wherein a height of the membrane is less than one percent a height of the carrier substrate.

28. The optical component of claim 1 , the optical element is integrated into a surface of the membrane and a portion of the optical element extends away from the surface.

29. The optical component of claim 1 , wherein the carrier substrate includes a thickness in one dimension between 200 μm and 500 μm.

30. The optical component of claim 1 , wherein the membrane includes a thickness in one dimension of less than 2 μm.

31. An optical component comprising:

a chip comprising a carrier substrate including a semiconductor material and a membrane disposed directly on an exterior planar membrane-carrying surface of the carrier substrate, the membrane formed integrally with the carrier substrate;

a cavity formed in the carrier substrate, the cavity including a first end and a second end, the membrane including a cavity-spanning portion that spans the cavity at its first end, the cavity-spanning portion of the membrane being transparent to light in a wavelength range of interest; and

at least one optical element formed on or in the cavity-spanning portion of the membrane, the at least one optical element to modify light,

wherein the optical component is only a passive component and does not include any complementary metal oxide semiconductor (CMOS) circuitry, and

wherein a height of the membrane is at most 10 micrometers.

32. The optical component of claim 31 , wherein the carrier substrate comprises at least one of Group III, IV, or V semiconductor material.

33. The optical component of claim 31 , wherein the at least one optical element includes a convex surface that extends away from an exterior surface of the membrane.

Assignments (1)

Continuity (1)

References Cited (38)