Microprobe tips and methods for making

• US 7,412,767 B2
• Filed: 01/03/2005
• Issued: 08/19/2008
• Est. Priority Date: 02/04/2003
• Status: Active Grant

• Current Assignee: Microfabrica Incorporated (Technoprobe S.P.A.)
• Original Assignee: Microfabrica Incorporated (Technoprobe S.P.A.)
• Inventors: Zhang, Gang, Cohen, Adam L., Lockard, Michael S., Arat, Vacit, Kim, Kieun, Kruglick, Ezekiel J. J., Chen, Richard T., Kumar, Ananda H., Larsen, Willa M.
• Primary Examiner(s): Arbes; C. J
• Application Number:
  US11/029,217
• Publication Number:
  US 20050221644A1
• Time in Patent Office: 1,324 Days
• Field of Search: 298/25, 298/30, 298/42, 298/43, 298/74, 298/76, 298/77, 298/78, 298/79, 228/180.5
• US Class Current: 29/879
• CPC Class Codes: G01R 1/0483 Sockets for un-leaded IC's having matrix type contact fields, e.g. BGA or PGA devices; Sockets for unpackaged, naked chips for IC's with connecting points around the edges only G01R1/0433
• CPC Class Codes: G01R 1/06716 Elastic
• CPC Class Codes: G01R 1/07357 with flexible bodies, e.g. buckling beams
• CPC Class Codes: G01R 31/2886 Features relating to contacting the IC under test, e.g. probe heads; chucks G01R31/2865 takes precedence, test connections, e.g. test sockets, or probes per se, G01R1/04 or G01R1/06
• CPC Class Codes: Y10T 29/49147 Assembling terminal to base
• CPC Class Codes: Y10T 29/49149 by metal fusion bonding
• CPC Class Codes: Y10T 29/49204 Contact or terminal manufacturing
• CPC Class Codes: Y10T 29/49208 by assembling plural parts
• CPC Class Codes: Y10T 29/4921 with bonding
• CPC Class Codes: Y10T 29/49211 of fused material
• CPC Class Codes: Y10T 29/49213 Metal

Abstract

Embodiments of the present invention are directed to the formation of microprobe tips elements having a variety of configurations. In some embodiments tips are formed from the same building material as the probes themselves, while in other embodiments the tips may be formed from a different material and/or may include a coating material. In some embodiments, the tips are formed before the main portions of the probes and the tips are formed in proximity to or in contact with a temporary substrate. Probe tip patterning may occur in a variety of different ways, including, for example, via molding in patterned holes that have been isotropically or anisotropically etched silicon, via molding in voids formed in over exposed photoresist, via molding in voids in a sacrificial material that have formed as a result of the sacrificial material mushrooming over carefully sized and located regions of dielectric material, via isotropic etching of a the tip material around carefully sized placed etching shields, via hot pressing, and the like.

Claims

1. A method for creating a contact structure, comprising:

forming a contact tip having a desired configuration;

forming a compliant probe structure from a plurality of adhered layers of electrochemically deposited material where each layer undergoes a planarization operation prior to formation of a subsequent layer; and

adhering the contact tip to the probe structure to form a contact structure.

3. The method of claim 1 wherein the contact tip has a shape that is derived from depositing a tip material in a pattern etched in silicon.

4. The method of claim 1 wherein the contact tip has a shape that is derived at least in part via molding contact tip material in voids formed in patterned photoresist.

5. The method of claim 1 wherein the contact tip has a shape that is derived at least in part via etching of a patterned tip material.

6. The method of claim 1 wherein the contact tip has a shape that is derived at least in part via isotropic etching of a tip material around etching shields.

7. The method of claim 1 wherein the contact tip has a shape that is derived at least in part via hot pressing.

8. The method of claim 1 wherein the contact tip comprises a different material than the compliant probe structure.

9. The method of claim 1 wherein the contact tip comprises the same material as the probe structure.

10. The method of claim 1 wherein the contact tip comprises a coating material.

11. The method of claim 1 wherein the contact tip comprises a coating material and the probe structure comprises a coating material.

12. The method of claim 11 wherein the coating material on the tip is different from the coating material on the probe structure.

13. The method of claim 12 wherein the coating material on the tip is the same as the coating material on the probe structure.

2. A method for creating a contact structure, comprising:

forming a contact tip having a desired configuration;

forming a compliant probe structure electrochemically; and

adhering the contact tip to the probe structure to form a contact structure,

wherein the contact tip has a shape that is derived at least in part from the mushrooming of an electrodeposited sacrificial material over a dielectric material.

14. A method for creating a contact structure, comprising:

forming a contact tip having a desired configuration;

forming compliant probe structure from a plurality of adhered layers of deposited conductive structural material, where each layer comprises a conducitve structural material and a conductive sacrificial material, where each layer undergoes a planarization operation to bring a surface of the conductive structural material and the conductive sacrificial material to a common level, and where conductive sacrificial material is removed from multiple layers after formation of plurality of adhered layers; and

adhering the contact tip to the probe structure to form a contact structure.