Vapor cells and related systems and methods

Patent metadata

Field	Value
Publication number	US-11764796-B2
Application number	US-202217678655-A
Country	US
Kind code	B2
Filing date	Feb 23, 2022
Priority date	Nov 11, 2021
Publication date	Sep 19, 2023
Grant date	Sep 19, 2023

Abstract

Vapor cells may include a body including a cavity within the body. A first substrate bonded to a second substrate at an interface within the body, at least one of the first substrate, the second substrate, or an interfacial material between the first and second substrates may define at least one recess or pore in a surface. A smallest dimension of the at least one recess or pore may be about 500 microns or less, as measured in a direction parallel to at least one surface of the first substrate partially defining the cavity.

First claim

What is claimed is:

1. A vapor cell, comprising:
a body defining a cavity within the body, the body comprising a first substrate bonded to a second substrate at an interface, a first window located on a side of the first substrate opposite the second substrate, and a second window located on a side of the second substrate opposite the first substrate; and
at least one of the first substrate, the second substrate, or an interfacial material between the first substrate and the second substrate, defining at least one recess or pore, a smallest dimension of the at least one recess or pore being about 500 microns or less, as measured in a direction parallel to at least one surface of the first substrate partially defining the cavity, the at least one recess or pore distanced from the first window and the second window.

2. The vapor cell of claim 1 , wherein:
the interfacial material comprises an oxide material interposed between the first substrate and the second substrate; and
the interfacial material is recessed relative to the first substrate and the second substrate to define the at least one recess between the first substrate and the second substrate, the first substrate, the interfacial material, and the second substrate cooperatively defining the at least one recess.

3. The vapor cell of claim 2 , wherein the body comprises a stack of substrates comprising at least the first substrate and the second substrate and a respective mass of the interfacial material interposed between each pair of substrates of the stack of substrates, wherein at least one mass of the interfacial material is recessed relative to each pair of substrates between which it is interposed define a series of recesses comprising the at least one recess.

4. The vapor cell of claim 1 , wherein the first substrate comprises a first silicon material, the second substrate comprises a second silicon material, and the interfacial material comprises a silicon oxide material.

5. The vapor cell of claim 1 , wherein the body comprises the at least one recess and the body comprises alternating regions of disparate materials, the disparate materials comprising the interfacial material and a substrate material of the first substrate, the second substrate, or epitaxially grown, each region of the interfacial material of the disparate materials recessed relative to adjacent regions of the substrate material of the disparate materials to define the at least one recess between the adjacent regions of the substrate material.

6. The vapor cell of claim 5 , wherein the interfacial material comprises an oxide material and the substrate material comprises a non-oxide material.

7. The vapor cell of claim 1 , wherein a region of at least one of the first substrate or the second substrate partially defining the cavity comprises a porous material.

8. The vapor cell of claim 7 , wherein the region is of the second substrate, and wherein the second substrate is interposed between, and bonded to, the first substrate and a third substrate of the body.

9. The vapor cell of claim 7 , wherein the region is located proximate to the interface between the first substrate and the second substrate.

10. The vapor cell of claim 9 , wherein a diameter of the cavity proximate to the region is less than a diameter of the cavity distal from the region.

11. The vapor cell of claim 7 , wherein the body comprises a stack of substrates comprising at least the first substrate and the second substrate, a first region of the first substrate partially defining the cavity comprises a first mass of the porous material, and a second region of the second substrate partially defining the cavity comprises a second mass of the porous material.

12. The vapor cell of claim 11 , wherein the first region and the second region are located distal from an interface between the first substrate and the second substrate.

13. A method of making a vapor cell, comprising:
providing a body, the body comprising a first substrate bonded to a second substrate at an interface, a first window located on a side of the first substrate opposite the second substrate, and a second window located on a side of the second substrate opposite the first substrate;
defining a cavity within the body; and
forming, in at least one of the first substrate, the second substrate, or an interfacial material between the first substrate and the second substrate, at least one pore or recess having a smallest dimension of about 500 microns or less, as measured in a direction parallel to at least one surface of the first substrate partially defining the cavity, the at least one recess or pore distanced from the first window and the second window.

14. The method of making a vapor cell of claim 13 , wherein forming the at least one pore or recess comprises forming the at least one pore by exposing the at least one of the first substrate, the second substrate, or the interfacial material to chemical processing.

15. The method of claim 13 , wherein forming the at least one pore or recess comprises forming the at least one recess by selectively etching a portion of the interfacial material between the first substrate and the second substrate to recess the interfacial material relative to the first substrate and the second substrate.

16. The method of claim 13 , wherein forming the at least one pore or recess comprises forming the at least one recess by selectively etching regions of oxide material interposed between regions of non-oxide material of at least one of the first substrate or the second substrate to recess each region of the oxide material relative to adjacent regions of the non-oxide material.

17. The method of claim 13 , wherein forming the at least one pore or recess comprises rendering a material of a region of at least one of the first substrate or the second substrate partially defining the cavity porous through chemical treatment or by patterning and selective etching of the substrate.

18. The method of claim 17 , comprising placing the second substrate comprising the region between, and bonding the second substrate to, the first substrate and a third substrate of the body.

19. The method of claim 18 , comprising placing the region proximate to the interface between the first substrate and the second substrate.

20. The method of claim 19 , wherein defining the cavity comprises rendering a diameter of the cavity proximate to the region less than a diameter of the cavity distal from the region.

21. The method of claim 17 , wherein rendering the material of the region of the at least one of the first substrate or the second substrate partially defining the cavity porous comprises rendering the material of a first region of the first substrate partially defining the cavity porous to form a first mass of the porous material and rendering a material of a second region of the second substrate partially defining the cavity porous to form a second mass of the porous material.

22. The method of claim 21 , comprising placing the first and the second porous regions distal from the interface between the first substrate and the second substrate.

23. A system, comprising:
an emitter positioned and oriented to direct radiation through windows of a vapor cell; and
a detector positioned and oriented to detect the radiation;
wherein the vapor cell comprises a body defining a cavity within the body, the body comprising:
a first substrate bonded to a second substrate at an interface;
a first window

Assignees

• Microchip Tech Inc

Inventors

• Lutwak Robert
• Chen Bomy

Classifications

• G04F5/14 Primary

  using atomic clocks · CPC title

• H03L7/26 Primary

  using energy levels of molecules, atoms, or subatomic particles as a frequency reference · CPC title