MEMS device and manipulation method for micro-objects

Patent metadata

Field	Value
Publication number	US-10899605-B2
Application number	US-201815911705-A
Country	US
Kind code	B2
Filing date	Mar 5, 2018
Priority date	Mar 5, 2018
Publication date	Jan 26, 2021
Grant date	Jan 26, 2021

Abstract

A micro-electro-mechanical systems (MEMS) includes a flexible membrane that creates a suction force by flexing to permit manipulation of a microscale object. The MEMS element includes a casing structure; a flexible membrane attached to the casing structure; and an electrode structure, wherein a voltage applied to the electrode structure causes the flexible membrane to flex relative to the casing structure. The flexible membrane and the casing structure define a gap into which the flexible membrane may flex, and a foot extending from the flexible membrane in a direction away from the casing structure, wherein the foot and the flexible membrane define a clearance region on an opposite side of the flexible membrane from the gap. When the MEMS element interacts with an object to be manipulated the foot spaces the membrane apart from the object, and flexing of the membrane generates the suction force for manipulating the object.

First claim

What is claimed is:

1. A micro-electro-mechanical systems (MEMS) element comprising:
a casing structure;
a flexible membrane attached to the casing structure;
an electrode structure, wherein voltages applied to the electrode structure cause the flexible membrane to flex relative to the casing structure;
wherein the flexible membrane and the casing structure define a gap into which the flexible membrane may flex; and
a foot extending from the flexible membrane in a direction away from the casing structure, wherein the foot and the flexible membrane define a clearance region on an opposite side of the flexible membrane from the gap, and when the MEMS element interacts with an object to be manipulated the foot spaces the membrane apart from the object;
wherein the clearance region is open oppositely from the flexible membrane.

2. The MEMS element of claim 1 , wherein the flexible membrane is fixed at an anchor portion between the casing structure and the foot.

3. The MEMS element of claim 1 , wherein:
the electrode structure includes a first electrode located on the casing and a second electrode associated with the flexible membrane;
the casing structure comprises a substrate and a casing wall that extends from the substrate;
the first electrode is deposited on the substrate; and
the flexible membrane is attached to a surface of the casing wall opposite from the substrate.

4. The MEMS element of claim 3 , wherein the substrate and the casing wall are made of different materials.

5. The MEMS element of claim 3 , wherein the substrate and the casing wall comprise a single piece of a same material.

6. The MEMS element of claim 1 , wherein the foot extends inward from the casing wall along the flexible membrane.

7. The MEMS element of claim 1 , wherein when a voltage is applied to the electrode structure to generate an attractive force between the flexible membrane and a substrate of the casing structure, the flexible membrane is in an on state and flexes in a direction toward the substrate of the casing structure; and
when a voltage is not applied to the electrode structure, the flexible membrane is in an off state and the flexible membrane does not flex relative to an initial position.

8. The MEMS element of claim 7 , wherein when a voltage is applied to the electrode structure in a manner that renders the flexible membrane electrically repulsive relative to the substrate of the casing structure, the flexible membrane is in a repel state and flexes in a direction away from the substrate of the casing structure.

9. The MEMS element of claim 1 , further comprising a drive circuit for controlling voltages applied to the electrode structure.

10. The MEMS element of claim 9 , wherein the drive circuit includes one or more transistors.

11. The MEMS element of claim 10 , wherein the one or more transistors includes a first p-type transistor and a first n-type transistor that are electrically connected to a first electrode located on the casing structure, and a second p-type transistor and a second n-type transistor that are electrically connected to a second electrode associated with the flexible membrane.

12. The MEMS element of claim 10 , wherein the one or more transistors are TFT transistors.

13. The MEMS element of claim 9 , wherein the drive circuit further comprises one or more memory elements for storing voltages applied to the electrode structure.

14. The MEMS element of claim 13 , wherein the one or more memory elements includes a first capacitor that stores a voltage applied to a first electrode located on the casing structure, and a second capacitor that stores a voltage applied to a second electrode associated with the flexible membrane.

15. A micro-electro-mechanical systems (MEMS) element comprising:
a casing structure;
a flexible membrane attached to the casing structure;
an electrode structure, wherein voltages applied to the electrode structure cause the flexible membrane to flex relative to the casing structure;
wherein the flexible membrane and the casing structure define a gap into which the flexible membrane may flex; and
a foot extending from the flexible membrane in a direction away from the casing structure, wherein the foot and the flexible membrane define a clearance region on an opposite side of the flexible membrane from the gap, and when the MEMS element interacts with an object to be manipulated the foot spaces the membrane apart from the object;
wherein an outer surface of the foot opposite from the flexible membrane includes an adhesive material.

16. A method of manipulating an object using a micro-electro-mechanical systems (MEMS) element comprising the steps of:
providing a MEMS element including: a casing structure; a flexible membrane attached to the casing structure; an electrode structure, wherein the flexible membrane and the casing structure define a gap into which the flexible membrane may flex; and a foot extending from the flexible membrane in a direction away from the casing structure, wherein the foot and the flexible membrane define a clearance region on an opposite side of the flexible membrane from the gap, and when the MEMS element is placed on the object the foot spaces the membrane apart from the object;
placing the MEMS element against the object to be manipulated;
applying a voltage to the electrode structure to place the MEMS element in an on state in which the flexible membrane flexes from an initial position to a flexed position relative to the casing structure, whereby the MEMS element generates a suction force against the object by the flexing of the flexible membrane; and
retaining the object to the MEMS element by operation of the suction force to perform a manipulation of the object.

17. The method of manipulating an object of claim 16 , further comprising removing the voltage from the electrode structure to place the MEMS element in an off state, whereby the flexible membrane returns to the initial position to remove the suction force.

18. The method of manipulating an object of claim 16 , further comprising applying a voltage to the electrode structure to place the MEMS element in a repel state in which the flexible membrane flexes from the flexed or initial position to an opposite flexed position relative to the on state, whereby the MEMS element generates a repulsion force against the object to release the object from the MEMS element.

19. The method of manipulating an object of claim 18 , wherein:
the foot further includes an adhesive material for adhering the MEMS element to the object;
when the MEMS element is placed in the off state from the on state, the object is retained by the MEMS element by operation of the adhesive material; and
the MEMS element is placed in the repel state to release the object from the MEMS element.

20. The method of manipulating an object of claim 16 , wherein performing the manipulation of the object comprises:
using the suction force to lift the object from a first surface;
moving a location of the object while the suction force retains the object to the MEMS element; and
removing the suction force and releasing the object from the MEMS element, thereby placing the object on a second surface.

Assignees

• Sharp Kk

Inventors

• Hopkin Hywel
• Smith Nathan

Classifications

• B81C99/002 Primary

  Apparatus for assembling MEMS, e.g. micromanipulators (micromanipulators per se B25J7/00) · CPC title

• B81B2201/038

  Microengines and actuators not provided for in B81B2201/031 - B81B2201/037 · CPC title

• B81B2203/0127

  Diaphragms, i.e. structures separating two media that can control the passage from one medium to another; Membranes, i.e. diaphragms with filtering function · CPC title

• B81C1/00158

  Diaphragms, membranes (manufacture process for semi-permeable inorganic membranes B01D67/0039) · CPC title

• B81C1/00333

  Aspects relating to packaging of MEMS devices, not covered by groups B81C1/00269 - B81C1/00325 · CPC title