MICRO-ELECTRO-MECHANICAL SYSTEM (MEMS) AND RELATED ACTUATOR BUMPS, METHODS OF MANUFACTURE AND DESIGN STRUCTURES

• US 20150054100A1
• Filed: 10/21/2014
• Published: 02/26/2015
• Est. Priority Date: 06/20/2011
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: JAHNES, Christopher V., STAMPER, Anthony K.
• Granted Patent: US 9,593,007 B2
• Time in Patent Office: Days
• US Class Current: 257/418
• CPC Class Codes: B81B 2201/016 having a bridge fixed on two ends and connected to one or more dimples
• CPC Class Codes: B81B 2203/0163 Spring holders
• CPC Class Codes: B81B 3/001 Structures having a reduced contact area, e.g. with bumps or with a textured surface
• CPC Class Codes: B81B 3/0021 Transducers for transforming electrical into mechanical energy or vice versa dynamo-electric machines H02K99/00; electrostatic machines H02N1/00; piezoelectric devices H10N30/00
• CPC Class Codes: B81B 3/0059 Constitution or structural means for controlling the movement not provided for in groups B81B3/0037 - B81B3/0056
• CPC Class Codes: B81B 3/0072 For controlling internal stress or strain in moving or flexible elements, e.g. stress compensating layers
• CPC Class Codes: B81B 7/0006 Interconnects
• CPC Class Codes: B81B 7/008 MEMS characterised by an electronic circuit specially adapted for controlling or driving the same B81B7/0087 takes precedence; arrangements for starting, regulating, braking, or otherwise controlling an actuator H02N; control arrangements or circuits for visual indicators G09G3/00
• CPC Class Codes: B81C 1/00015 for manufacturing microsystems
• CPC Class Codes: B81C 1/0015 Cantilevers switches using MEMS H01H1/0036; electrostatic relays using micromechanics H01H59/0009; microelectro-mechanical resonators H03H9/02244
• CPC Class Codes: B81C 1/00476 removing a sacrificial layer B81C1/00912 takes precedence
• CPC Class Codes: G06F 30/30 Circuit design
• CPC Class Codes: H10N 30/2042 Cantilevers, i.e. having one fixed end
• CPC Class Codes: H10N 30/304 Beam type
• CPC Class Codes: H10N 30/308 Membrane type
• CPC Class Codes: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 29/49005 Acoustic transducer
• CPC Class Codes: Y10T 29/4908 Acoustic transducer
• CPC Class Codes: Y10T 29/49121 Beam lead frame or beam lead device

Abstract

Micro-Electro-Mechanical System (MEMS) structures, methods of manufacture and design structures are provided. The method of forming a MEMS structure includes forming a wiring layer on a substrate comprising actuator electrodes and a contact electrode. The method further includes forming a MEMS beam above the wiring layer. The method further includes forming at least one spring attached to at least one end of the MEMS beam. The method further includes forming an array of mini-bumps between the wiring layer and the MEMS beam.

Claims

1. A MEMS structure, comprising:

a first set of wires on a substrate, comprising fixed actuator electrodes and a contact;

a second set of wires above the first set of wires;

at least one spring attached to at least one end of at least one of the second set of wires to accommodate a lateral shift of the second set of wires; and

an array of mini-bumps between the first set of wires and the second set of wires, wherein the array of mini-bump are structured to prevent portions of the second set of wires from contacting the fixed actuator electrodes, upon actuation.

2. The MEMS structure of claim 1, wherein a size of a space between the fixed actuator electrodes or a size of a dummy actuator is dimensioned based on a lateral shift of the MEMS structure.

3. The MEMS structure of claim 2, wherein the at least one spring comprises at least one lateral bendable wire.

4. The MEMS structure of claim 3, wherein the at least one spring has a predetermined spring constant based on a coefficient of thermal expansion (CTE) mismatch between materials of the MEMS structure and the at least one spring.

5. The MEMS structure of claim 1, wherein the MEMS structure comprises one or more layers of metal and dielectric and the layers have differing thermal expansion coefficients which, over a temperature range, induces beam curvature upwards or downwards, and the at least one spring provides for lateral beam shift when temperature changes, thereby reducing temperature-induced variation in actuation gap or beam curvature.

6. A method of forming a MEMS structure, comprising:

forming a MEMS beam;

forming a plurality of electrodes;

forming an array of mini-bumps between the MEMS beam and the plurality of electrodes; and

determining a size of a space between fixed actuator electrodes of the plurality of electrodes or a dummy actuator based on a lateral shift of the MEMS beam.

7. The method of claim 6, wherein the determining provides a landing location of the array of mini-bumps when there is a lateral shift of the MEMS beam.

8. The method of claim 6, wherein determining comprises a location in which the array of the mini-bumps centered or nearly centered within the space between the fixed actuator electrodes.

9. The method of claim 6, further comprising forming a spring extending from at least one end of the MEMS beam.

10. The method of claim 6, further comprising forming at least one spring extending both ends of the MEMS beam.

11. The method of claim 10, wherein the MEMS beam comprises one or more layers of metal and dielectric and the layers have differing thermal expansion coefficients which, over a temperature range, induces beam curvature upwards or downwards, and the at least one spring provides for lateral beam shift when temperature changes, thereby reducing temperature-induced variation in actuation gap or beam curvature.

12. A hardware description language (HDL) design structure encoded on a machine-readable data storage medium, the HDL design structure comprising elements that when processed in a computer-aided design system generates a machine-executable representation of a MEMS structure, wherein the HDL design structure comprises:

a first set of wires on a substrate, comprising fixed actuator electrodes and a contact;

a second set of wires above the first set of wires;

at least one spring attached to at least one end of at least one of the second set of wires to accommodate a lateral shift of the second set of wires; and

an array of mini-bumps between the first set of wires and the second set of wires, wherein the array of mini-bump are structured to prevent portions of the second set of wires from contacting the fixed actuator electrodes, upon actuation.