Probe testing structure

• US 7,250,626 B2
• Filed: 03/05/2004
• Issued: 07/31/2007
• Est. Priority Date: 10/22/2003
• Status: Active Grant

• Current Assignee: FormFactor Incorporated
• Original Assignee: Cascade Microtech Incorporated (FormFactor Incorporated)
• Inventors: Lesher, Timothy E.
• Primary Examiner(s): Hu; Shouxiang
• Application Number:
  US10/794,246
• Publication Number:
  US 20050088191A1
• Time in Patent Office: 1,243 Days
• Field of Search: 257/48, 257/275, 324/614, 324/754, 333/251
• US Class Current: 257/48
• CPC Class Codes: G01R 1/06772 High frequency probes
• CPC Class Codes: G01R 35/005 Calibrating; Standards or reference devices, e.g. voltage or resistance standards, "golden" references G01R33/0035, G01R35/002 take precedence
• CPC Class Codes: G01R 35/007 Standards or reference devices, e.g. voltage or resistance standards, "golden references"

Abstract

A calibration structure for probing devices.

Claims

1. A calibration substrate for calibrating a probe comprising:

(a) a first conductive member associated with a first calibration test site and supported by said substrate suitable to be electrically interconnected with a first signal path of said probe;

(b) a second conductive member associated with said first calibration test site and supported by said substrate suitable to be electrically interconnected with a second signal path of said probe, said second conductive member electrically isolated from said first conductive member;

(c) a third conductive member associated with said first calibration test site and supported by said substrate suitable to be electrically interconnected with a ground path of said probe, said third conductive member electrically isolated from each of said first and second conductive members;

(d) a fourth conductive member associated with a second calibration test site, spaced apart from said first calibration test site, and supported by said substrate suitable to be electrically interconnected with a first signal path of another probe;

(e) a fifth conductive member associated with said second calibration test site supported by said substrate suitable to be electrically interconnected with a second signal path of said another probe, said fifth conductive member electrically isolated from said fourth conductive member;

(f) a sixth conductive member associated with said second calibration test site supported by said substrate suitable to be electrically interconnected with a ground path of said another probe, said sixth conductive member electrically isolated from each of said fourth and fifth conductive members; and

(g) a resistive member supported by said substrate and positioned between said third conductive member and said sixth conductive member and extending 100% of the distance between said third conductive member and said sixth conductive member and having a width substantially equal to that of said third and sixth conductive members.

2. The substrate of claim 1 wherein the S11 characteristic from said first, second, and third conductive members has a loss of less than 0.05 dB between 30 GHz and 50.

3. The substrate of claim 1 wherein the S11 characteristic from said first, second, and third conductive members has a Q factor of less than 5 between 30 GHz and 50.

4. The substrate of claim 1 wherein said resistive material matches within 10 percent the imaginary part of the primary mode conversion between 30 GHz and 50.

5. The substrate of claim 1 wherein said resistive material that includes a member has a resistance that reduces a resonance effect between 10 GHz and 100 GHz that would have otherwise occurred if the resistive material was not included to a level less than 50% of what would have otherwise occurred.