Micro fluidic valves, agitators, and pumps and methods thereof

• US 20020182091A1
• Filed: 05/31/2002
• Published: 12/05/2002
• Est. Priority Date: 05/31/2001
• Status: Active Grant

• Current Assignee: Rochester Institute of Technology
• Original Assignee: Rochester Institute of Technology
• Inventors: Potter, Michael D.
• Granted Patent: US 7,195,393 B2
• Time in Patent Office: Days
• US Class Current: 417/413.3
• CPC Class Codes: F04B 43/043 Micropumps
• CPC Class Codes: F15C 5/00 Manufacture of fluid circuit elements; Manufacture of assemblages of such elements integrated circuits
• CPC Class Codes: F16K 2099/008 Multi-layer fabrications
• CPC Class Codes: F16K 2099/0094 Micropumps
• CPC Class Codes: F16K 99/0001 Microvalves microdevices B81B1/00; manufacture or treatment of devices or systems in or on a substrate B81C1/00; microfluidic structures B01L3/5027; micropumps F04B19/006
• CPC Class Codes: F16K 99/0007 of cantilever type
• CPC Class Codes: F16K 99/0015 Diaphragm or membrane valves
• CPC Class Codes: F16K 99/0051 using electrostatic means

Abstract

A valve which has a structure with at least one opening and a member which has a fixed static charge and also has a first position exposing the opening and a second position sealing the opening. A method for making the valve includes providing a structure with at least one opening and providing a member having a fixed static charge where the member has a first position exposing the opening and a second position sealing the opening. An agitator includes a base with at least one trench, a structure with at least one opening, and a membrane with a fixed static charge. The structure is connected to the base over the trench with the opening in the structure extending through to the trench in the base. The membrane is connected to the base across at least a portion of the trench. A pump includes a base with at least one trench, a structure with at least two openings, a membrane with a fixed static charge, a first cantilever arm having a fixed static charge, and a second cantilever arm having a fixed static charge. The structure is connected to the base over the trench with the openings in the structure extending through to the trench in the base. The membrane is connected to the base across at least a portion of the trench. The first cantilever arm has a first position exposing one of the openings and a second position sealing the one of the openings. The second cantilever arm has a first position exposing another one of the openings and a second position sealing the another one of the openings.

Claims

1. A device for micro fluidics, the device comprising:

a structure with at least one opening; and

a member having a fixed static charge, the member having a first position exposing the opening and a second position sealing the opening.

2. The device as set forth in claim 1 further comprising at least two control electrodes which are adjacent to and spaced from different sides of the member.

3. The device as set forth in claim 2 wherein at least a portion of the structure adjacent the opening comprises one of the control electrodes.

4. The device as set forth in claim 1 wherein the member comprises a cantilever arm.

5. The device as set forth in claim 4 wherein the cantilever arm comprises two or more insulators deposited on each other with an interface between each pair of the insulators, the fixed static charge is imbedded at at least one of the interfaces between the two or more insulators.

6. The device as set forth in claim 4 wherein the cantilever arm comprises an electret with the fixed static charge.

7. The device as set forth in claim 4 wherein a free end of the cantilever arm is located adjacent to and spaced from the opening in the structure.

8. The device as set forth in claim 4 wherein a free end of the cantilever arm is located against the opening in the structure.

9. The device as set forth in claim 1 wherein the member comprises a membrane with an outer perimeter, at least a portion of the outer perimeter of the membrane is connected to the structure about the opening.

10. The device as set forth in claim 9 wherein the membrane comprises two or more insulators deposited on each other with an interface between each pair of the insulators, the fixed static charge is imbedded at at least one of the interfaces between the two or more insulators

11. The device as set forth in claim 9 wherein the membrane comprises an electret with the fixed static charge.

12. The device as set forth in claim 9 wherein an interior portion of the membrane is located adjacent to and spaced from the opening in the structure to define a chamber.

13. The device as set forth in claim 9 wherein an interior portion of the membrane is located against the opening in the structure.

15. The method as set forth in claim 14 further comprising providing at least two control electrodes which are adjacent to and spaced from different sides of the member.

16. The method as set forth in claim 15 wherein at least a portion of the structure adjacent the opening comprises one of the control electrodes.

17. The method as set forth in claim 15 wherein providing a member having a fixed static charge further comprises:

depositing a first sacrificial material over a portion of a base;

depositing a first insulator over the first sacrificial material and another portion of the base;

depositing a second insulator over the first insulator; and

imbedding the fixed static charge at an interface between the first and second insulators.

18. The method as set forth in claim 17 wherein providing a structure with at least one opening further comprises:

depositing a second sacrificial material over at least a portion of the member;

depositing a structure layer on at least a portion of the second sacrificial material; and

forming an opening in the structure layer.

19. The method as set forth in claim 18 wherein the deposited structure layer is made of a conductive material to form one of the control electrodes.

20. The method as set forth in claim 18 further comprising removing the first and second sacrificial materials.

21. The method as set forth in claim 17 wherein providing a structure with at least one opening further comprises:

depositing a structure layer over at least a portion of the member, the structure layer in contact with, but not connected to the member; and

forming an opening in the structure layer, the opening extending to a portion of the member in contact with the structure layer.

22. The method as set forth in claim 21 wherein the deposited structure layer is made of a conductive material to form a control electrode and further comprising providing another control electrode which is adjacent to and spaced from an opposing side of the member from the structure.

23. The method as set forth in claim 21 further comprising removing the first sacrificial material.

24. The method as set forth in claim 17 wherein providing at least two control electrodes further comprises:

forming an opening in the base;

depositing a conductive material in the opening in the base to from one of the control electrodes on one side of the member; and

forming another control electrode on another side of the member.

25. The method as set forth in claim 15 wherein providing a member having a fixed static charge further comprises:

forming a first opening in a base;

depositing a first sacrificial material in at least a portion of the first opening in the base;

depositing a first insulator over at least a portion of the deposited first sacrificial material and another portion of the base;

depositing a second insulator over the first insulator; and

imbedding the fixed static charge at an interface between the first and second insulators.

26. The method as set forth in claim 25 wherein providing a structure with at least one opening further comprises:

depositing a second sacrificial material over at least a portion of the pair of insulators in the first opening in the base;

depositing a structure layer on at least a portion of the second sacrificial material, the second insulator and the base; and

forming an opening in the structure layer adjacent and spaced from the second insulator.

27. The method as set forth in claim 26 wherein the deposited structure layer is made of a conductive material to form one of the control electrodes.

28. The method as set forth in claim 27 further comprising removing the first and second sacrificial materials.

29. The method as set forth in claim 25 wherein providing a structure with at least one opening further comprises:

depositing a structure layer over at least a portion of the second insulator and the base, the structure layer in contact with, but not connected to the member; and

forming an opening in the structure layer, the opening extending to a portion of the second insulator in contact with the structure layer.

30. The method as set forth in claim 29 wherein the deposited structure layer is made of a conductive material to form one of the control electrodes.

31. The method as set forth in claim 29 further comprising removing the first sacrificial material.

32. The method as set forth in claim 25 wherein providing the control electrode further comprises:

forming a second opening in the first opening in the base; and

depositing a conductive material in the second opening in the base to from one of the control electrodes on one side of the member; and

forming another control electrode on another side of the member.

14. A method for making a micro fluidic device, the method comprising:

providing a structure with at least one opening; and

providing a member having a fixed static charge, the member having a first position exposing the opening and a second position sealing the opening.

33. An agitator comprising:

a base with at least one trench;

a structure with at least one opening, the structure connected to the base over the trench with the opening in the structure extending through to the trench in the base; and

a membrane with a fixed static charge, the membrane connected to the base across at least a portion of the trench.

34. The agitator as set forth in claim 33 further comprising at least two control electrodes which are adjacent to and spaced from different sides of the membrane.

35. The agitator as set forth in claim 34 wherein at least a portion of the structure adjacent the opening comprises one of the control electrodes.

36. The agitator as set forth in claim 33 wherein the membrane comprises two or more insulators deposited on each other with an interface between each pair of the insulators, the fixed static charge is imbedded at at least one of the interfaces between the two or more insulators

37. The agitator as set forth in claim 33 wherein the membrane comprises an electret with the fixed static charge.

39. The method as set forth in claim 38 wherein one of the control electrodes is in the base.

40. The method as set forth in claim 38 wherein at least a portion of the structure adjacent the opening comprises one of the control electrode.

41. The method as set forth in claim 38 wherein the membrane comprises two or more insulators deposited on each other with an interface between each pair of the insulators, the fixed static charge is imbedded at at least one of the interfaces between the two or more insulators.

42. The method as set forth in claim 38 wherein the membrane comprises an electret with the fixed static charge.

38. A method for agitating one or more substances, the method comprising:

placing the one or more substances in a trench in a base through an opening in a structure, the structure connected to the base over the trench;

applying a varying bias to at least two control electrode which are adjacent to and spaced from different sides of a membrane with a fixed static charge, the membrane connected to the base across at least a portion of the trench; and

moving the membrane towards and away from one of the control electrodes based on the applied varying bias.

43. A pump comprising:

a base with at least one trench;

a structure with at least two openings, the structure connected to the base over the trench with the openings in the structure extending through to the trench in the base;

a membrane with a fixed static charge, the membrane connected to the base across at least a portion of the trench;

a first cantilever arm having a fixed static charge, the first cantilever arm having a first position exposing one of the openings and a second position sealing the one of the openings; and

a second cantilever arm having a fixed static charge, the second cantilever arm having a first position exposing another one of the openings and a second position sealing the another one of the openings.

44. The pump as set forth in claim 43 further comprising a first control electrode which is adjacent to and spaced from the membrane, a second control electrode which is adjacent and spaced from the first cantilever arm, a third control electrode which is adjacent and spaced from the second cantilever arm, and at least a fourth control electrode which is adjacent and spaced from another side from the membrane from the first control electrode, which is adjacent and spaced from another side from the first cantilever arm from the second control electrode, and which is adjacent and spaced from another side from the second cantilever arm from the second control electrode.

45. The pump as set forth in claim 43 wherein at least a portion of the structure comprises the fourth control electrode.

46. The pump as set forth in claim 43 wherein at least one of the membrane, first cantilever arm, and second cantilever arm comprises two or more insulators deposited on each other with an interface between each pair of the insulators, the fixed static charge is imbedded at at least one of the interfaces between the two or more insulators.

47. The method as set forth in claim 43 wherein at least one of the membrane, first cantilever arm, and second cantilever arm comprises an electret with the fixed static charge.

49. The method as set forth in claim 48 further comprising:

applying a fifth bias to the second control electrode and fourth control electrode; and

moving the first cantilever arm away from a first opening in a structure in response to the applied fifth bias.

50. The method as set forth in claim 49 further comprising:

applying a sixth bias to the third control electrode and the fourth electrode; and

moving the second cantilever arm towards the second opening in the structure to seal the second opening in response to the applied sixth bias.

48. A method for pumping one or more substances, the method comprising:

applying a first bias to a first control electrode and a fourth control electrode which are adjacent to and spaced from different sides of a membrane with a first fixed static charge, the membrane is connected to a base across at least a portion of a trench in the base;

moving the membrane towards and away from the first control electrode based on the applied first bias to pump the one or more substances into the trench in the base through the first opening in the structure, the structure is connected to the base over the trench;

applying a second bias to a second control electrode and the fourth control electrode which are adjacent to and spaced from different sides of a first cantilever arm with a second fixed static charge;

moving the first cantilever arm towards the first opening in the structure to seal the first opening in response to the applied second bias;

applying a third bias to a third control electrode and the fourth control electrode which are adjacent to and spaced from different sides of a second cantilever arm with a third fixed static charge;

moving the second cantilever arm away from the second opening in the structure to open the second opening in response to the applied third bias;

applying a fourth bias to the first control electrode and the fourth control electrode; and

moving the membrane toward the first electrode based on the applied fourth bias to pump the one or more substances out of the trench in the base through the second opening in the structure.