MICROCHIP SUBSTANCE DELIVERY DEVICES HAVING LOW-POWER ELECTROMECHANICAL RELEASE MECHANISMS

• US 20160074323A1
• Filed: 09/11/2014
• Published: 03/17/2016
• Est. Priority Date: 09/11/2014
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Wright, Steven L., Chey, S. Jay, Dang, Bing, Knickerbocker, John U., Latzko, Kenneth F., Branquinho Teresa Maria, Joana Sofia, Turlapati, Lavanya, Webb, Bucknell C.
• Granted Patent: US 9,937,124 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A61K 9/0097 Micromachined devices; Microelectromechanical systems [MEMS]; Devices obtained by lithographic treatment of silicon; Devices comprising chips intradermal microneedle arrays A61K9/0021; MEMS in general B81B7/02
• CPC Class Codes: A61M 2205/0244 Micromachined materials, e.g. made from silicon wafers, microelectromechanical systems [MEMS] or comprising nanotechnology
• CPC Class Codes: A61M 31/002 Devices for releasing a drug at a continuous and controlled rate for a prolonged period of time artificial gland structures or devices A61F2/022; intra-uterine contraceptive devices A61F6/14; tampons for introducing into the vagina A61F13/20, A61L15/00; suppositories or bougies for intra-vaginal or intra-uterine application A61K9/02; physical forms of medicinal preparations for sustained or differential drug release A61K9/20, A61K9/50
• CPC Class Codes: A61N 1/0412 Specially adapted for transcutaneous electroporation, e.g. including drug reservoirs
• CPC Class Codes: A61N 1/0428 Specially adapted for iontophoresis, e.g. AC, DC or including drug reservoirs
• CPC Class Codes: A61N 1/0444 Membrane
• CPC Class Codes: A61N 1/0448 Drug reservoir

Abstract

Electromechanical substance delivery devices are provided which implement low-power electromechanical release mechanisms for controlled delivery of substances such as drugs and medication. For example, an electromechanical device includes a substrate having a cavity formed in a surface of the substrate, a membrane disposed on the surface of the substrate covering an opening of the cavity, and a seal disposed between the membrane and the surface of the substrate. The seal surrounds the opening of the cavity, and the seal and membrane are configured to enclose the cavity and retain a substance within the cavity. An electrode structure is configured to locally heat a portion of the membrane in response to a control voltage applied to the electrode structure, and create a stress that causes a rupture in the locally heated portion of the membrane to release the substance from within the cavity.

Claims

1. An electromechanical device, comprising:

a substrate comprising a cavity formed in a surface of the substrate;

a membrane disposed on the surface of the substrate covering an opening of the cavity;

a seal disposed between the membrane and the surface of the substrate, wherein the seal surrounds the opening of the cavity, and wherein the seal and membrane are configured to enclose the cavity and retain a substance within the cavity; and

an electrode structure configured to locally heat a portion of the membrane in response to a control voltage applied to the electrode structure, and create a stress that causes a rupture in the locally heated portion of the membrane to release the substance from within the cavity.

2. The device of claim 1, wherein the substance comprises medication.

3. The device of claim 1, wherein the locally heated portion of the membrane has a lateral dimension that is less than about two times a thickness of the membrane.

4. The device of claim 1, wherein a portion of the electrode structure comprises a V-shaped electrode, wherein an apex portion of the V-shaped electrode has a width that is less than a width of a remaining portion of the V-shaped electrode, and wherein the apex portion is configured to provide said localized heating of the portion of the membrane.

5. The device of claim 4, wherein the V-shaped electrode is formed with an angle of about 108 degrees to about 120 degrees.

6. The device of claim 1, wherein the membrane comprises a plurality of voids formed within the membrane, wherein the plurality of voids are configured to reduce a strength of the locally heated portion of the membrane and facilitate rupturing of the locally heated portion of the membrane.

7. The device of claim 6, wherein the membrane is formed in a tensile-stressed state, such that a portion of the membrane is configured to peel back away from a ruptured portion of the membrane.

8. The device of claim 1, further comprising a stress layer disposed on the membrane, wherein the stress layer is configured to apply a tensile stress to the membrane and cause a portion of the membrane to peel back away from a ruptured portion of the membrane.

9. The device of claim 1, wherein the membrane is formed of an insulating material.

10. The device of claim 1, wherein the locally heated portion of the membrane comprises a metallic material that is configured to melt due to said localized heating thereof.

11. An electromechanical device, comprising:

a substrate comprising a cavity formed in a surface of the substrate;

a seal disposed on the surface of the substrate surrounding an opening of the cavity;

a membrane disposed on the surface of the substrate covering the opening of the cavity, wherein the seal and membrane are configured to enclose the cavity and retain a substance within the cavity;

an electrode structure comprising a first contact, a second contact, and a plurality of filaments arranged adjacent to each other, wherein the plurality of filaments are electrically connected in parallel to the first and second contacts of the electrode structure, wherein the filaments are configured to melt in succession in response to a control voltage applied to the first and second contacts, and cause a rupture in a portion of the membrane adjacent to the plurality of filaments to release the substance from within the cavity.

12. The device of claim 11, wherein the plurality of filaments include parallel filaments disposed between the first and second contacts, wherein each filament includes a fuse portion that is configured to melt, wherein a centrally disposed one of the filaments has a width that is greater than widths of the other filament structures, and wherein the widths the other filaments disposed on each side of the centrally disposed filament are made successively smaller.

13. The device of claim 12, wherein the fuse portions of the filaments are arranged along a V-shaped line, wherein a fuse portion of the centrally disposed filament is aligned to an apex of the V-shaped line.

14. The device of claim 13, wherein membrane comprises a plurality of voids formed within the membrane along the V-shaped line, wherein the plurality of voids are configured to reduce a strength of the membrane and facilitate rupturing a portion of the membrane adjacent to the fuse portions of the filaments.

15. The device of claim 11, wherein the plurality of filaments include circular filament structures that are concentrically arranged and connected to the first and second contacts.

16. The device of claim 15, wherein the membrane comprises a plurality of voids formed within the membrane along one or more radial lines that radially extend from a center point within an innermost circular filament.

17. An electromechanical device, comprising:

a substrate comprising a cavity formed in a surface of the substrate;

a membrane disposed on the surface of the substrate covering an opening of the cavity, wherein the membrane comprises a plurality of voids formed within the membrane, wherein the plurality of voids are configured to reduce a strength of the portion of the membrane within which the voids are formed;

a seal disposed between the membrane and the surface of the substrate, wherein the seal surrounds the opening of the cavity, wherein the seal and membrane are configured to enclose the cavity and retain a substance within the cavity; and

an electrode structure configured to thermally expand in response to a control voltage applied to the electrode structure and apply a tensile stress to the portion of the membrane within which the voids are formed and cause a rupture in said portion of the membrane to release the substance from within the cavity.

18. The device of claim 17, wherein a portion of the electrode structure comprises a V-shaped electrode, and wherein the plurality of voids are formed within the membrane along a V-shaped line adjacent to an inner edge of the V-shaped electrode.

19. The device of claim 17, wherein a portion of the electrode structure comprises a semi-circular electrode, and wherein the plurality of voids are formed within the membrane along a semi-circular line adjacent to an inner edge of the semi-circular electrode.

20. The device of claim 17, wherein the membrane is formed in a tensile-stressed state, such that a portion of the membrane is configured to peel back away from a ruptured portion of the membrane.

21. The device of claim 17, wherein the membrane comprises an expansion groove to enable stretching of the membrane due to thermal expansion of the electrode structure.

22. An electromechanical device, comprising:

a substrate comprising a cavity formed in a surface of the substrate;

a metallic membrane disposed on the surface of the substrate covering an opening of the cavity;

a seal disposed between the metallic membrane and the surface of the substrate, wherein the seal surrounds the opening of the cavity, and wherein the seal and metallic membrane are configured to enclose the cavity and retain a substance within the cavity; and

an electrode structure configured to locally heat a portion of the metallic membrane in response to a control voltage applied to the electrode structure, and cause melting of the locally heated portion of the metallic membrane to release the substance from within the cavity.

23. An electromechanical device, comprising:

a substrate comprising a cavity formed in a surface of the substrate;

a membrane disposed on the surface of the substrate covering an opening of the cavity;

a seal disposed between the membrane and the surface of the substrate, wherein the seal surrounds the opening of the cavity, and wherein the seal and membrane are configured to enclose the cavity and retain a substance within the cavity; and

an electrode structure formed on the membrane, wherein the electrode structure is formed in a tensile-stressed state, and comprises a fuse portion,

wherein membrane comprises a plurality of voids formed within the membrane along one or more edges of the electrode structure, wherein the plurality of voids are configured to reduce a strength of a portion of the membrane along the one or more edges of the electrode structure, and

wherein the fuse portion of the electrode structure is configured to melt in response to a control voltage applied to the electrode structure and cause the electrode structure to peel back and rupture the portion of the membrane in which the plurality of voids are formed along the one or more edges of the electrode structure.

24. The device of claim 23, wherein the electrode structure comprises a first and a second triangular-shaped electrode having a first apex and a second apex, respectively, wherein the fuse portion is connected between the first apex and the second apex.

25. The device of claim 23, wherein the plurality of voids formed within the membrane comprise:

a first set of voids that extend along a first V-shaped line adjacent to first edges of the first and second triangular-shaped electrodes; and

a second set of voids that extend along a second V-shaped line adjacent to second edges of the first and second triangular-shaped electrodes.

26. An electromechanical device, comprising:

a substrate comprising a cavity formed in a surface of the substrate;

a membrane disposed on the surface of the substrate covering an opening of the cavity;

a seal disposed between the membrane and the surface of the substrate, wherein the seal surrounds the opening of the cavity, and wherein the seal and membrane are configured to enclose the cavity and retain a substance within the cavity;

an electrode structure configured to locally heat a least a portion of the seal in response to a control voltage applied to the electrode structure, and melt the locally heated portion of the seal to release the substance from within the cavity.

27. The device of claim 26, wherein the seal is formed of a metallic material.

28. The device of claim 26, wherein the seal is formed of a non-metallic material.

29. The device of claim 26, wherein the locally heated portion of the seal is disposed to overlap at least a portion of the electrode structure.

30. The device of claim 26, wherein the locally heated portion of the seal is disposed adjacent to at least a portion of the electrode structure.

31. The device of claim 26, wherein portions of the seal and the electrode structure are configured to melt in response to the control voltage applied to the electrode structure

32. An electromechanical device, comprising:

a substrate comprising a cavity formed in a surface of the substrate;

a membrane disposed on the surface of the substrate covering an opening of the cavity;

a seal disposed between the membrane and the surface of the substrate, wherein the seal surrounds the opening of the cavity, and wherein the seal and membrane are configured to enclose the cavity and retain a substance within the cavity; and

an electrode structure configured to locally heat a region in proximity to the seal in response to a control voltage applied to the electrode structure, and cause a mechanical stress that is effective to break at least a portion of the seal to release the substance from within the cavity.

33. The device of claim 32, wherein the mechanical stress comprises a shear stress that is applied to an interface connection between the seal and the membrane.

34. The device of claim 32, further comprising a polymer material containing volatile components, wherein the polymer material is disposed in the locally heated region, wherein the polymer material is configured to release the volatile components in response to the heating of the polymer material and cause shearing of the seal.