# US 2013/0156993 A1 · Micro-electro-mechanical system (mems) structures and design structures

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 2013/0156993 A1
- Document ID: US20130156993A1
- Status: Published application
- Kind: A1
- Application number: 13/326,604
- Filed: 2011-12-15
- Published: 2013-06-20
- Earliest claimed: 2011-12-15
- Assignees: International Business Machines Corporation
- Inventors: Brian M. CZABAJ; David A. DeMUYNCK; Anthony K. STAMPER
- Web page: https://patentgrep.com/patent/US20130156993A1

## CPC

- H10D 48/50: Devices controlled by mechanical forces, e.g. pressure
- B81C 1/0015: {Cantilevers (switches using MEMS H01H1/0036; electrostatic relays using micromechanics H01H59/0009; microelectro-mechanical resonators H03H9/02244)}
- B81C 1/00246: {Monolithic integration, i.e. micromechanical structure and electronic processing unit are integrated on the same substrate}
- G06F 30/39: Circuit design at the physical level (physical level design for reconfigurable circuits G06F30/347)
- B81B 2201/014: having a cantilever fixed on one side connected to one or more dimples
- B81B 2203/0118: Cantilevers
- B81B 2207/015: the micromechanical device and the control or processing electronics being integrated on the same substrate
- H01H 2057/006: {Micromechanical piezoelectric relay}
- Y10T 428/239: Complete cover or casing
- H10D: INORGANIC ELECTRIC SEMICONDUCTOR DEVICES
- B81C: PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS (making microcapsules or microballoons B01J13/02; processes or apparatus specially adapted for the manufacture or treatment of piezoelectric, electrostrictive or magnetostrictive elements per se H10N30/01)
- G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N)
- B81B: MICROSTRUCTURAL DEVICES OR SYSTEMS, e.g. MICROMECHANICAL DEVICES (piezoelectric, electrostrictive or magnetostrictive elements per se H10N30/00, H10N35/00)
- H01H: ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES (contact cables H01B7/10; electrolytic self-interrupters H01G9/18; emergency protective circuit arrangements H02H; switching by electronic means without contact-making H03K17/00)
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

Micro-Electro-Mechanical System (MEMS) structures, methods of manufacture and design structures are disclosed. The method includes layering metal and insulator materials on a sacrificial material formed on a substrate. The method further includes masking the layered metal and insulator materials. The method further includes forming an opening in the masking which overlaps with the sacrificial material. The method further includes etching the layered metal and insulator materials in a single etching process to form the beam structure, such that edges of the layered metal and insulator material are aligned. The method further includes forming a cavity about the beam structure through a venting.

## Claims

### Claim 1

A method comprising:
forming a first metal layer on an at least a first insulator layer coating an underlying first sacrificial material;
forming a second insulator layer on the first metal layer;
forming a second metal layer on the insulator layer;
forming a third insulator layer on the second metal layer;
forming a mask on the third insulator layer to protect portions of the third insulator layer, the second metal layer, the second insulator layer, the first insulator layer and the first metal layer, wherein an opening in the mask partially overlaps with the underlying first sacrificial material;
in single removal process, removing exposed portions of the first insulator layer, the second insulator layer, and third insulator layer, and the first metal layer and the second metal layer, to form a beam structure, and to expose the overlapped portion of the underlying first sacrificial material;
forming a second sacrificial material over the beam structure and in contact with the exposed portion of the underlying first sacrificial material;
providing a lid on the second sacrificial material; and
venting, through the lid, the second sacrificial material and the underlying first sacrificial material to form an upper and lower chamber about the beam structure.

### Claim 2 (depends on 1)

The method of claim 1, wherein the single removal process comprising an etching step.

### Claim 3 (depends on 1)

The method of claim 1, wherein the single removal process achieves a vertical alignment of edges of the beam structure.

### Claim 4 (depends on 1)

The method of claim 1, further comprising:
forming the first insulator layer between the first metal layer and the underlying sacrificial material; and
forming the second insulator layer between an exposed surface of the second metal layer and the underlying first sacrificial material, wherein:
forming the mask is formed on the second insulator layer; and
the single removal process removes portions of the first insulator layer and the second insulator layer, which contributes to the beam structure.

### Claim 5 (depends on 4)

The method of claim 4, wherein the first insulator layer is formed in a trench formed in the underlying first sacrificial material, and the first metal layer is formed in the trench over the first insulator layer.

### Claim 6 (depends on 5)

The method of claim 5, wherein the venting results in an oxide bump extending below the first metal layer, and facing a fixed electrode formed on a substrate.

### Claim 7 (depends on 1)

The method of claim 1, further comprising:
forming a wiring layer on a substrate, below the underlying first sacrificial material; and
after the venting, forming a via through the lid and to the underlying wiring layer, on a side of the upper chamber and the lower chamber.

### Claim 8 (depends on 1)

The method of claim 1, further comprising:
forming a wiring on a same level as the first metal layer; and
after the venting, forming a via through the lid and to the wiring, on a side of the upper chamber and the lower chamber.

### Claim 9 (depends on 1)

The method of claim 1, further comprising:
forming a wiring on a same level as the second metal layer; and
after the venting, forming a via through the lid and to the wiring, on a side of the upper chamber and the lower chamber.

### Claim 10 (depends on 1)

The method of claim 1, further comprising, prior to the formation of the second sacrificial layer, forming an insulating spacer on the exposed sides of the beam structure.

### Claim 11

A method of forming a beam structure, comprising:
layering metal and insulator materials on a sacrificial material formed on a substrate;
masking the layered metal and insulator materials;
forming an opening in the masking which overlaps with the sacrificial material;
etching the layered metal and insulator materials in a single etching process to form the beam structure, such that edges of the layered metal and insulator material are aligned; and
forming a cavity about the beam structure through a venting.

### Claim 12 (depends on 11)

The method of claim 11, wherein the layering comprises:
forming a first metal layer over the sacrificial material;
forming an oxide material over the first metal; and
forming a second metal layer over the oxide material.

### Claim 13 (depends on 12)

The method of claim 12, wherein the layering further comprises:
forming an insulator layer under the first metal layer, directly in contact with the sacrificial material; and
forming another insulator layer directly on the second metal layer,
wherein the etching includes etching of portions of the insulator layer and the another insulator layer.

### Claim 14 (depends on 11)

The method of claim 11, further comprising:
forming a metal wiring layer on a substrate below the sacrificial material; and
after the cavity formation, forming a via to the metal wiring layer.

### Claim 15 (depends on 11)

The method of claim 11, further comprising:
forming a wiring on a same level as the first metal layer; and
after the cavity formation, forming a via to the wiring.

### Claim 16 (depends on 11)

The method of claim 11, further comprising:
forming a wiring on a same level as the second metal layer; and
after the cavity formation, forming a via to the wiring.

### Claim 17 (depends on 11)

The method of claim 11, further comprising:
forming a trench in the sacrificial material;
forming an insulator in the trench, prior to the forming of the first metal layer; and
forming of the first metal layer is provided on the insulator.

### Claim 18

A structure comprising a composite beam structure having self aligned edges and located between an upper chamber and a lower chamber.

### Claim 19 (depends on 18)

The structure of claim 18, wherein the composite beam structure comprises a metal, oxide and metal layering.

### Claim 20

A method in a computer-aided design system for generating a functional design model of a MEMS structure, the method comprising:
generating a functional representation of a composite beam structure having self aligned edges and located between an upper chamber and a lower chamber.

### Claim 21 (depends on 20)

The method of claim 20, wherein the functional design model comprises a netlist.

### Claim 22 (depends on 20)

The method of claim 20, wherein the functional design model resides on a storage medium as a data format used for the exchange of layout data of integrated circuits.

### Claim 23 (depends on 20)

The method of claim 20, wherein the functional design model resides in a programmable gate array.