Integrated circuit switches, design structure and methods of fabricating the same

• US 8,569,091 B2
• Filed: 08/27/2009
• Issued: 10/29/2013
• Est. Priority Date: 08/27/2009
• Status: Active Grant

• Current Assignee: Globalfoundries US Incorporated (GlobalFoundries, Inc.), RF Micro Devices Incorporated (Qorvo, Inc.)
• Original Assignee: International Business Machines Corporation
• Inventors: Anderson, Felix P., McDevitt, Thomas L., Stamper, Anthony K.
• Primary Examiner(s): SUN, YU-HSI DAVID
• Application Number:
  US12/548,697
• Publication Number:
  US 20110049649A1
• Time in Patent Office: 1,524 Days
• Field of Search: 257/50, 257/52, 257/415, 257/E29.324, 257/E21.215, 257/E21.249, 438/52, 438/704
• US Class Current: 438/52
• CPC Class Codes: B81B 2201/014 having a cantilever fixed on one side connected to one or more dimples
• CPC Class Codes: B81B 3/0018 Structures acting upon the moving or flexible element for transforming energy into mechanical movement or vice versa, i.e. actuators, sensors, generators
• 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 1/00333 Aspects relating to packaging of MEMS devices, not covered by groups B81C1/00269 - B81C1/00325
• CPC Class Codes: B81C 2203/0136 Growing or depositing of a covering layer
• CPC Class Codes: B81C 2203/0145 Hermetically sealing an opening in the lid
• CPC Class Codes: G06F 30/39 Circuit design at the physical level physical level design for reconfigurable circuits G06F30/347
• CPC Class Codes: H01L 21/302 to change their surface-physical characteristics or shape, e.g. etching, polishing, cutting

Abstract

Integrated MEMS switches, design structures and methods of fabricating such switches are provided. The method includes forming at least one tab of sacrificial material on a side of a switching device which is embedded in the sacrificial material. The method further includes stripping the sacrificial material through at least one opening formed on the at least one tab which is on the side of the switching device, and sealing the at least one opening with a capping material.

Claims

1. A method of manufacturing a MEMS switch comprising:

forming MEMS structures in a lower and upper cavity, which are connected by a via formed through the MEMS structures and are temporarily filled with a sacrificial material, wherein the forming the MEMS structures comprises;

forming a first electrode layer on a lower layer of the sacrificial material;

forming a first dielectric layer on the first electrode layer;

forming a second electrode layer on the first dielectric layer

forming a first insulator layer on a surface of the first electrode layer; and

forming a second insulator layer on the second electrode layer;

forming a second dielectric layer surrounding portions of the lower and upper cavity and over the MEMS structures;

opening a vent hole in the second dielectric layer on a side of the MEMS structures over the lower cavity;

stripping the sacrificial material to form a void about the MEMS structures using a dry or wet etchant; and

sealing the vent hole with a capping material.

2. The method of claim 1, further comprising:

forming at least one tab on a side of the MEMS structures, the at least one tab being formed from the sacrificial material; and

forming the second dielectric layer over the at least one tab,

wherein the vent hole is in the second dielectric layer on the at least one tab.

3. The method of claim of claim 2, wherein the lower layer of the sacrificial material embeds a contact electrode and a forcing electrode of the MEMS structures and forms the at least one tab, simultaneously.

4. The method of claim 2, wherein the lower layer of the sacrificial material, which embeds a contact electrode and a forcing electrode, is formed at a different time than the at least one tab.

5. The method of claim 2, wherein the vent hole is one of fully aligned over the at least one tab, offset with respect to the at least one tab and formed on a side of the at least one tab.

6. The method of claim 2, wherein one of:

the sacrificial material is silicon and the stripping is performed using XeF₂ gas; and

the sacrificial material is Polymethylglutarimide (PMGI) and the stripping is performed using N-methyl-2-pyrrolidine (NMP) and/or dimethylsulfoxide (DMSO)-based removers.

7. The method of claim 1, wherein the via is formed through the first insulator layer, the first electrode layer, the first dielectric layer, the second electrode layer, and the second insulator layer.

8. The method of claim 7, wherein the sacrificial material surrounds the MEMS structures and is stripped from under the MEMS structures through the via.

9. The method of claim 1, wherein the MEMS structures are formed as a cantilever beam having a free end.