Packaged strain actuator

• US 6,069,433 A
• Filed: 10/03/1997
• Issued: 05/30/2000
• Est. Priority Date: 01/27/1994
• Status: Expired due to Term

• Current Assignee: Cymer Incorporated (ASML Holding NV)
• Original Assignee: Active Control eXperts, Inc. (ASML Holding NV)
• Inventors: Lundstrom, Mark E., Moore, Jeffrey W., Lazarus, Kenneth B., Crawley, Edward F.
• Primary Examiner(s): BUDD, MARK OSBORNE
• Application Number:
  US08/943,645
• Time in Patent Office: 970 Days
• Field of Search: 310/316, 310/317, 310/319, 310/328, 310/330-332, 310/334, 310/366, 310/338-340, 310/324
• US Class Current: 310/333
• CPC Class Codes: G03F 7/70725 control
• CPC Class Codes: G03F 7/70758 Drive means, e.g. actuators, motors for long- or short-stroke modules or fine or coarse driving
• CPC Class Codes: G03F 7/709 Vibration, e.g. vibration detection, compensation, suppression or isolation
• CPC Class Codes: H04R 17/08 signals being recorded or played back by vibration of a stylus in two orthogonal directions simultaneously
• CPC Class Codes: H10N 30/02 Forming enclosures or casings
• CPC Class Codes: H10N 30/204 using bending displacement, e.g. unimorph, bimorph or multimorph cantilever or membrane benders
• CPC Class Codes: H10N 30/2041 Beam type
• CPC Class Codes: H10N 30/2042 Cantilevers, i.e. having one fixed end
• CPC Class Codes: H10N 30/2044 having multiple segments mechanically connected in series, e.g. zig-zag type
• CPC Class Codes: H10N 30/208 using shear or torsion displacement, e.g. d15 type devices
• CPC Class Codes: H10N 30/87 Electrodes or interconnections, e.g. leads or terminals
• CPC Class Codes: H10N 30/88 Mounts; Supports; Enclosures; Casings
• CPC Class Codes: Y10T 29/42 Piezoelectric device making
• CPC Class Codes: Y10T 29/49126 Assembling bases
• CPC Class Codes: Y10T 29/49128 Assembling formed circuit to base
• CPC Class Codes: Y10T 29/49146 with encapsulating, e.g., potting, etc.

Abstract

A modular actuator assembly includes one or more plates or elements of electro-active material bonded to an electroded sheet, preferably by a structural polymer to form a card. The card is sealed, and may itself constitute a practical device, such as a vane, shaker, stirrer, lever, pusher or sonicator for direct contact with a solid or immersion in a fluid, or may be bonded by a stiff adhesive to make a surface-to-surface mechanical coupling with a solid workpiece,device, substratesmachine or sample. The structural polymer provides a bending stiffness such that the thin plate does not deform to its breaking point, and a mechanical stiffness such that shear forces are efficiently coupled from the plate to the workpiece. In further embodiments, the card may include active circuit elements for switching, powering or processing signals, and/or passive circuit elements for filtering, matching or damping signals, so that few or no connections to outside circuitry are required. The actuator assembly can be manufactured in quantity, to provide a versatile actuator with uniform mechanical and actuation characteristics, that introduces negligible mass loading to the workpiece. The cards themselves may be arranged as independent mechanical actuators, rather than strain-transfer actuators, in which the induced strain changes the position of the card. Various arrangements of pinned or cantilevered cards may act as a pusher, bender or other motive actuator, and structures such as powered bellows may be formed directly by folding one or more suitably patterned cards.

Claims

1. An electro-active device comprising a plurality of layers laminated about at least one electro-active ceramic layer to form an electro-active ceramic package, and including

a first and a second electro-active ceramic layer, at least one of said first and second electro-active ceramic layers extending over a region and having a first surface and a second surface opposite to said first surface region;

a flexible circuit covering a substantial portion of said first surface of said electro-active ceramic layer, the flexible circuit including a non-conductive polymer film layer having opposing first and second surfaces and a conductive lead layer, said first surface of said polymer film layer being attached to said conductive lead layer; and

a bonding layer attaching said electro-active ceramic layer to said flexible circuit,

wherein said first and second electro-active ceramic layers are oriented to produce torsional actuation

wherein said lead layer includes a pattern of lead segments forming a conductive line extending in a path across said film layer and protruding therefrom;

wherein said flexible circuit is configured such that

i) said conductive line extends substantially entirely across and is attached to said first surface of the electro-active ceramic layer for energizing said entire first surface while bridging cracks; and

ii) said polymer film layer covers said electro-active ceramic layer and said conductive line, and

wherein said bonding layer attaches said electro-active ceramic layer to said flexible circuit such that in-plane strain of the electro-active ceramic layer is shear-coupled from substantially said entire first surface of the electro-active ceramic layer through the flexible circuit

so that said in-plane strain is effectively transferred to said second surface of the polymer film layer for utilization of strain produced by the electro-active ceramic layer.

2. An electro-active device according to claim 1, wherein said first and second electro-active ceramic layers are in different layers of the device and are connected for moving in different senses.