PLANAR CAVITY MEMS AND RELATED STRUCTURES, METHODS OF MANUFACTURE AND DESIGN STRUCTURES

• US 20140166463A1
• Filed: 02/20/2014
• Published: 06/19/2014
• Est. Priority Date: 06/25/2010
• 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 9,352,954 B2
• Time in Patent Office: Days
• US Class Current: 200/600
• CPC Class Codes: B81B 2201/014 having a cantilever fixed on one side connected to one or more dimples
• CPC Class Codes: B81B 2203/0118 Cantilevers
• CPC Class Codes: B81B 2203/04 Electrodes
• 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 1/00365 having low tensile stress between layers
• CPC Class Codes: B81C 1/00476 removing a sacrificial layer B81C1/00912 takes precedence
• CPC Class Codes: B81C 1/00619 Forming high aspect ratio structures having deep steep walls
• CPC Class Codes: B81C 1/00626 Processes for achieving a desired geometry not provided for in groups B81C1/00563 - B81C1/00619
• CPC Class Codes: B81C 1/00666 Treatments for controlling internal stress or strain in MEMS structures
• CPC Class Codes: B81C 2201/0109 Sacrificial layers not provided for in B81C2201/0107 - B81C2201/0108
• CPC Class Codes: B81C 2201/013 Etching
• CPC Class Codes: B81C 2201/0167 by adding further layers of materials having complementary strains, i.e. compressive or tensile strain
• CPC Class Codes: B81C 2201/017 Methods for controlling internal stress of deposited layers not provided for in B81C2201/0164 - B81C2201/0169
• CPC Class Codes: B81C 2203/0136 Growing or depositing of a covering layer
• CPC Class Codes: B81C 2203/0172 Seals
• CPC Class Codes: G06F 2115/04 Micro electro-mechanical systems [MEMS]
• CPC Class Codes: G06F 30/39 Circuit design at the physical level physical level design for reconfigurable circuits G06F30/347
• CPC Class Codes: H01H 1/0036 Switches making use of microelectromechanical systems [MEMS] for electromagnetic relays H01H50/005; for electrostatic relays H01H59/0009
• CPC Class Codes: H01H 2057/006 Micromechanical piezoelectric relay
• CPC Class Codes: H01H 57/00 Electrostrictive relays; Piezoelectric relays
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 : Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H10N 30/306 : Cantilevers
• CPC Class Codes: Y10S 438/937 : Hillock prevention
• CPC Class Codes: Y10T 29/42 : Piezoelectric device making
• CPC Class Codes: Y10T 29/435 : Solid dielectric type
• CPC Class Codes: Y10T 29/49002 : Electrical device making
• CPC Class Codes: Y10T 29/49105 : Switch making
• CPC Class Codes: Y10T 29/49121 : Beam lead frame or beam lead device
• CPC Class Codes: Y10T 29/49126 : Assembling bases
• CPC Class Codes: Y10T 29/4913 : Assembling to base an electrical component, e.g., capacitor, etc.
• CPC Class Codes: Y10T 29/49155 : Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/5313 : Means to assemble electrical device

Abstract

A method of forming a Micro-Electro-Mechanical System (MEMS) includes forming a lower electrode on a first insulator layer within a cavity of the MEMS. The method further includes forming an upper electrode over another insulator material on top of the lower electrode which is at least partially in contact with the lower electrode. The forming of the lower electrode and the upper electrode includes adjusting a metal volume of the lower electrode and the upper electrode to modify beam bending.

Claims

1. A Micro-Electro-Mechanical System (MEMS) structure comprising a moveable beam comprising at least one insulator layer on a lower electrode such that a volume of the lower electrode is adjusted to modify beam bending characteristics.

2. The MEMS structure of claim 1, further comprising:

an upper electrode over the at least one insulator layer on top of the lower electrode,

wherein a metal volume of the lower electrode and a metal volume of the upper electrode are based at least on a layout of the lower electrode.

3. The MEMS structure of claim 2, wherein the lower electrode and the upper electrode are formed of a same material.

4. The MEMS structure of claim 3, wherein the lower electrode and the upper electrode are composed of Ti/AlCu/Ti/TiN.

5. The MEMS structure of claim 4, wherein a coefficient of thermal expansion (CTE) of the lower electrode and the upper electrode is approximated by AlCu.

6. The MEMS structure of claim 2, wherein the lower electrode and the upper electrode have identical layouts and same thicknesses.

7. The MEMS structure of claim 2, wherein one of the lower electrode and the upper electrode is as a slotted or holed layout and one of the upper electrode and the lower electrode, respectively, has a thickness of the slotted or holed layout, to match the metal volume of the lower electrode with the metal volume of the upper electrode.

8. The MEMS structure of claim 2, wherein the lower electrode and the upper electrode are asymmetric or different, and a thickness of one of the lower electrode and the upper electrode with a lower pattern factor is thickened to balance the metal volume of the lower electrode with the metal volume of the upper electrode.

9. The MEMS structure of claim 2, wherein a pattern factor ratio of the lower electrode to the upper electrode comprises 0.8:

1, and a volume ratio of the metal volume of the lower electrode to the metal volume of the upper electrode comprises 0.93;

1.

10. The MEMS structure of claim 1, wherein the moveable beam is formed from one or more metal layers, comprising a top metal and a bottom metal with an oxide layer there between.

11. The MEMS structure of claim 1, wherein the modified beam bending characteristics are provided over a temperature range of about −

55°

C. to 125°

C.

12. The MEMS structure of claim 2, wherein one of the lower electrode and the upper electrode comprises a slotted or holed layout and one of the upper electrode and the lower electrode, respectively, is thinned with respect to the slotted or holed layout, to match the metal volume of the lower electrode with the metal volume of the upper electrode.

13. The MEMS structure of claim 12, wherein the metal thickness of the upper electrode is thinned such that the metal volume of the upper electrode matches the metal volume of the lower electrode, when the layout of the lower electrode is slotted or holed;

and

the metal thickness of the upper electrode is the same as the metal thickness of the lower electrode when the layout of the lower electrode is identical to a layout of the upper electrode.

14. A design structure comprising data tangibly embodied in a machine readable storage medium for designing, manufacturing, or simulating a moveable beam, the data when processed on a data processing system generate a functional representation of the moveable beam, comprising:

at least one insulator layer on a conductor layer such that a volume of the conductor is adjusted to modify beam bending characteristics.

15. The design structure of claim 14, further comprising:

an upper electrode over the at least one insulator layer on top of the conductor layer,

wherein a metal volume of the conductor layer and a metal volume of the upper electrode are based at least on the layout of the conductor layer.