Method of constructing a membrane probe

• US 7,533,462 B2
• Filed: 12/01/2006
• Issued: 05/19/2009
• Est. Priority Date: 06/04/1999
• Status: Expired due to Fees

• Current Assignee: FormFactor Beaverton, Inc. (FormFactor Incorporated)
• Original Assignee: Cascade Microtech Incorporated (FormFactor Incorporated)
• Inventors: Bayne, Michael A., Smith, Kenneth, Gleason, Reed
• Primary Examiner(s): ARBES, CARL J
• Application Number:
  US11/607,156
• Publication Number:
  US 20070074392A1
• Time in Patent Office: 900 Days
• Field of Search: 298/25, 298/46, 298/48, 298/74, 298/76, 298/79, 298/84
• US Class Current: 29/874
• CPC Class Codes: G01R 1/06738 related to tip portion
• CPC Class Codes: G01R 1/06744 Microprobes, i.e. having dimensions as IC details
• CPC Class Codes: G01R 1/0735 arranged on a flexible frame or film
• CPC Class Codes: G01R 3/00 Apparatus or processes specially adapted for the manufacture or maintenance of measuring instruments , e.g. of probe tips
• CPC Class Codes: H05K 2201/0367 Metallic bump or raised conductor not used as solder bump
• CPC Class Codes: H05K 2201/09736 Varying thickness of a single conductor; Conductors in the same plane having different thicknesses
• CPC Class Codes: H05K 3/205 using a pattern electroplated or electroformed on a metallic carrier
• CPC Class Codes: H05K 3/4007 Surface contacts, e.g. bumps H05K3/4092 takes precedence; deposition of finish layers on pads H05K3/24; forming solder bumps H05K3/3457
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing
• CPC Class Codes: Y10T 29/49126 Assembling bases
• CPC Class Codes: Y10T 29/49128 Assembling formed circuit to base
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49165 by forming conductive walled aperture in base
• CPC Class Codes: Y10T 29/49174 Assembling terminal to elongated conductor
• CPC Class Codes: Y10T 29/49204 Contact or terminal manufacturing
• CPC Class Codes: Y10T 29/49208 by assembling plural parts
• CPC Class Codes: Y10T 29/49213 Metal
• CPC Class Codes: Y10T 29/49218 with deforming
• CPC Class Codes: Y10T 29/49815 Disassembling

Abstract

A substrate, preferably constructed of a ductile material and a tool having the desired shape of the resulting device for contacting contact pads on a test device is brought into contact with the substrate. The tool is preferably constructed of a material that is harder than the substrate so that a depression can be readily made therein. A dielectric (insulative) layer, that is preferably patterned, is supported by the substrate. A conductive material is located within the depressions and then preferably lapped to remove excess from the top surface of the dielectric layer and to provide a flat overall surface. A trace is patterned on the dielectric layer and the conductive material. A polyimide layer is then preferably patterned over the entire surface. The substrate is then removed by any suitable process.

Claims

1. A method of constructing a membrane probe comprising:

(a) providing a substrate;

(b) creating a depression within said substrate;

(c) locating conductive material within said depression;

(d) connecting a flexible conductive trace to said conductive material, said trace comprising a first length portion having a first width and a first thickness and a second length portion having a second width and a second thickness, at least one of said first width and said first thickness varying from, respectively, said second width and said second thickness; and

(e) removing said substrate from said conductive material.

2. The method of constructing a membrane probe of claim 1 wherein said first length portion of said conductive trace is proximate said connection of said trace to said conductive material and said second length portion is more remote from said connection to said conductive material than said first length portion and said first thickness is less than said second thickness.

3. The method of constructing a membrane probe of claim 1 wherein said first length portion of said conductive trace is proximate said connection of said trace to said conductive material and said second length portion is more remote from said connection to said conductive material than said first length portion and said first width is less than said second width.

4. A method of constructing a membrane probe comprising:

(a) providing a substrate;

(b) creating a depression within said substrate;

(c) locating conductive material within said depression, said conductive material including a connecting surface having a connecting surface length extending between a first edge and a second edge;

(d) connecting a flexible conductive trace to said conductive material, said trace comprising a first length portion having a first width and a first thickness and a length at least co-extensive with said connecting surface length and a second length portion having a second width and a second thickness, at least one of said first width and said first thickness varying from, respectively, said second width and said second thickness; and

(e) removing said substrate from said conductive material.

5. The method of constructing a membrane probe of claim 4 wherein said first thickness is less than said second thickness.

6. The method of constructing a membrane probe of claim 4 wherein said first width is less than said second width.

7. The method of constructing a membrane probe of claim 4 wherein said first length portion extends from a first end portion situated to a first side of said first edge of said connecting surface and a second end portion situated to a second side of said first edge, said first thickness being less than said second thickness.

8. A method of constructing a membrane probe comprising:

(a) providing a substrate;

(b) creating a depression within said substrate;

(c) locating conductive material within said depression, said conductive material including a connecting surface having a connecting surface length extending between a first edge and a second edge;

(d) connecting a conductive trace to said conductive material, said trace comprising;

(i) a first length portion having a first width and a first thickness and extending from a first end portion situated to a first side of said first edge of said connecting surface and a second end portion situated to a second side of said first edge;

(ii) a second length portion having a second width and a second thickness, said first thickness being less than said second thickness; and

(iii) a third length portion extending from said second end portion of said first length portion to a point situated more remote from said first edge of said connecting surface than said second end portion of said first length portion, said third length portion having a thickness greater than said first thickness; and

(e) removing said substrate from said conductive material.

9. A method of constructing a membrane probe comprising:

(a) providing a substrate;

(b) creating a depression within said substrate;

(c) locating conductive material within said depression, said conductive material including a connecting surface having a connecting surface length extending between a first edge and a second edge;

(d) connecting a conductive trace to said conductive material, said trace comprising;

(i) a first length portion having a first width and a first thickness and a length at least co-extensive with said connecting surface length;

(ii) a second length portion having a second width and a second thickness and extending from an end of said first length portion, at least one of said first width and said first thickness varying from, respectively, said second width and said second thickness; and

(iii) a third length portion extending from a second end of said second length portion;

said second thickness being less than one of said first thickness and a thickness of said third length portion and greater than the other of said first thickness and said thickness of said third length portion; and

(e) removing said substrate from said conductive material.

10. A method of constructing a membrane probe comprising:

(a) providing a substrate;

(b) creating a depression within said substrate;

(c) locating conductive material within said depression, said conductive material including a connecting surface;

(d) connecting a first conductive trace to said connecting surface, said conductive trace having a thickness defined by a first surface remote from said connecting surface;

(e) connecting a second conductive trace to said first surface of said first conductive trace, said second conductive trace having a thickness defined by a second surface remote from said first surface of said first conductive trace; and

(f) removing said substrate from said conductive material.

11. The method of constructing a membrane probe of claim 10 wherein said first conductive trace comprises a first conductor and said second conductive trace comprises a second conductor.

12. The method of constructing a membrane probe of claim 11 wherein said first conductor comprises copper and said second conductor comprises nickel.

13. The method of constructing a membrane probe of claim 10 further comprising the step of connecting a third conductive trace to said second surface of said second conductive trace.

14. The method of constructing a membrane probe of claim 10 wherein said first conductive trace comprises a first conductor, said second conductive trace comprises a second conductor and said third conductive trace comprises a conductor different from said second conductor.

15. The method of constructing a membrane probe of claim 14 wherein said first conductor and said third conductor comprise copper and said second conductor comprises nickel.