NICKEL STRUCTURES AND METHODS FOR MANUFACTURING THE SAME BY REMOVAL OF AN UNDERLYING MATERIAL

• US 20090226665A1
• Filed: 03/10/2008
• Published: 09/10/2009
• Est. Priority Date: 03/10/2008
• Status: Active Grant

• Current Assignee: Palo Alto Center Incorporated
• Original Assignee: Palo Alto Research Center, Inc. (Xerox Holdings Corp.)
• Inventors: CHEUNG, Patrick C. P.
• Granted Patent: US 7,755,260 B2
• Time in Patent Office: Days
• US Class Current: 428/138
• CPC Class Codes: H05K 2201/0338 Layered conductor, e.g. layered metal substrate, layered finish layer, layered thin film adhesion layer etched tri-metal structure H05K2201/0361
• CPC Class Codes: H05K 2201/0397 Tab forming integral conductive tabs H05K3/4092
• CPC Class Codes: H05K 2201/10083 Electromechanical or electro-acoustic component, e.g. microphone
• CPC Class Codes: H05K 2203/1184 Underetching, e.g. etching of substrate under conductors or etching of conductor under dielectrics; Means for allowing or controlling underetching
• CPC Class Codes: H05K 3/062 consisting of metals or alloys or metallic inorganic compounds H05K3/065 takes precedence
• CPC Class Codes: H05K 3/326 the printed circuit having integral resilient or deformable parts, e.g. tabs or parts of flexible circuits H05K3/365 takes precedence
• CPC Class Codes: H05K 3/4092 Integral conductive tabs, i.e. conductive parts partly detached from the substrate
• CPC Class Codes: Y10T 428/24331 including nonapertured component

Abstract

A printed circuit board includes a multiple-layer electrical circuit board and a nickel arm, wherein the nickel arm has an unconnected end located opposite to the connected end of the nickel arm, wherein the nickel arm has a front side and a backside located opposite to the front side of the nickel arm, wherein the backside of the nickel arm is located adjacent to the multiple layer electrical circuit board. A dimple is formed at the unconnected end of the nickel arm and on the front side of the nickel arm. An air gap is formed between the backside of the arm and the multiple layer electrical circuit board, wherein the air gap permits the arm to flex within the air gap. A lead zirconium titanate element is laminated to the printed circuit board, wherein the dimple on the front side of the arm contacts a surface of the lead zirconium titanate element, wherein a restoring spring force of the nickel arm maintains electrical contactivity between the dimple and the lead zirconium titanate element.

Claims

1. A structure comprising:

a multiple-layer electrical circuit board having an arm, wherein the arm is nickel and has an unconnected end located opposite to the connected end of the arm, wherein the arm has a front side and a backside located opposite to the front side of the arm, wherein the backside of the arm is located adjacent to the multiple layer electrical circuit board,

a dimple formed on the unconnected end on a front side of the arm, and

an air gap formed between the backside of the arm and the multiple layer electrical circuit board, permitting the arm to flex into space of the air gap.

2. The structure according to claim 1, further comprising:

an adhesive film laminated to the printed circuit board or the lead zirconium titanate element, wherein the adhesive film is translucent.

3. The structure according to claim 1, wherein the arm has a thickness from about 10 microns to about 15 microns.

4. The structure according to claim 1, wherein the dimple has a thickness of about 30 microns to about 70 microns.

5. The structure according to claim 1, wherein the air gap formed between the arm and the multiple-layer electrical circuit board is about 15 microns to about 45 microns.

6. A structure comprising:

a printed circuit board including

a multiple-layer electrical circuit board having an arm, wherein the arm is nickel and has an unconnected end located opposite to the connected end of the arm, wherein the arm has a front side and a backside located opposite to the front side of the arm, wherein the backside of the arm is located adjacent to the multiple layer electrical circuit board,

a dimple formed on the unconnected end on a front side of the arm,

an air gap formed between the backside of the arm and the multiple layer electrical circuit board, permitting the arm to flex into space of the air gap; and

a lead zirconium titanate element laminated to the printed circuit board, wherein the dimple contacts the lead zirconium titanate element, wherein a restoring spring force exerted by the arm maintains electrical contactivity between the dimple and the lead zirconium titanate element.

7. The structure according to claim 6, further comprising:

contact material applied at a contact point between the dimple of the arm and the lead zirconium titanate element.

8. The structure according to claim 7, wherein the contact material is a metal epoxy or a layer of metal solder.

9. The structure according to claim 8, wherein the metal epoxy is silver epoxy or the layer of metal solder is made of silver, tin, lead or combinations thereof and has a thickness of about 5 microns.

10. The structure according to claim 6, further comprising:

an adhesive film laminated to the printed circuit board or the lead zirconium titanate element, wherein the adhesive film is translucent.

11. The structure according to claim 6, wherein the arm has a thickness from about 6 microns to about 25 microns.

12. The structure according to claim 6, wherein the dimple has a thickness of about 30 microns to about 70 microns.

13. The structure according to claim 6, wherein the space of the air gap formed between the backside of the unconnected end of the arm and the multiple-layer electrical circuit board is about 15 microns to about 45 microns.

14. A method comprising:

forming a printed circuit board having a multiple layer electrical circuit board and an arm, wherein the arm is nickel and has an unconnected end located opposite to a connected end of the arm, wherein the arm has a front side and a backside located opposite to the front side of the arm, wherein the backside of the arm is adjacent to the multiple layer electrical circuit board, wherein sacrificial underlying material connects the multiple layer electrical circuit board and the backside of the arm; and

removing the sacrificial underlying material located between the backside of the arm and the multiple-layer electrical circuit board to form an air gap between the backside of the arm and the multiple layer electrical circuit board, permitting the arm to flex into space of the air gap.

15. The method according to claim 14, further comprising:

laminating the printed circuit board to a lead zirconium titanate element, wherein the front side of the arm contacts the lead zirconium titanate element, wherein the restoring spring force of the arm maintains electrical contactivity between the arm and the lead zirconium titanate element.

16. The method according to claim 14, further comprising:

plating a dimple onto the front side of the arm and at the unconnected end of the arm, wherein the dimple connects the arm to the lead zirconium titanate element.

17. The method according to claim 14, wherein the sacrificial underlying material is a copper precursor metal.

18. The method according to claim 14, further comprising:

heat tacking a translucent adhesive film to the printed circuit board or the lead zirconium titanate element.

19. The method according to claim 14, further comprising:

applying a contact material to a contact point where the front side of the arm contacts the lead zirconium titanate element.

20. The method according to claim 19, wherein the contact material is a metal epoxy or a layer of metal solder.

21. The method according to claim 20, wherein the metal epoxy is made of silver epoxy or the layer of metal solder is silver, tin, lead or combinations thereof.

22. The method according to claim 14, further comprising:

applying a chemical etchant to the printed circuit board to remove the sacrificial underlying material.

23. The method according to claim 14, wherein the unconnected end of the arm exhibits a restoring spring force of about 1 gram force to about 2 gram force.

24. The method according to claim 14, wherein the air gap formed between the arm and the multiple layer electrical circuit board is about 15 microns to about 45 microns.