Universal socketless test fixture

• US 7,768,283 B1
• Filed: 08/04/2009
• Issued: 08/03/2010
• Est. Priority Date: 08/04/2009
• Status: Active Grant

• Current Assignee: MACOM Connectivity Solutions, LLC (MACOM Technology Solutions Holdings, Inc.)
• Original Assignee: Applied Micro Circuits Corporation (MACOM Technology Solutions Holdings, Inc.)
• Inventors: Patterson, Joseph Martin
• Primary Examiner(s): Tang; Minh N
• Application Number:
  US12/535,533
• Time in Patent Office: 364 Days
• Field of Search: None
• US Class Current: 324/754.09
• CPC Class Codes: G01R 1/0408 Test fixtures or contact fields; Connectors or connecting adaptors; Test clips; Test sockets G01R1/067 takes precedence; mass production testing systems G01R31/59; testing of connections G01R31/66; for testing printed circuit boards G01R31/2808
• 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

Abstract

A universal socketless integrated circuit (IC) electrical test fixture is provided. The test fixture is made up of a probing platform to accept and heatsink an IC. The IC has electrical contacts formed on a bottom surface in an array of m rows, where each row includes n, or less contacts. A probe arm includes p probe pins, where p is greater than, or equal to n. A clamping mechanism mechanically interfaces the probe arm probe pins to a row of IC contacts under test. An electrical measurement device has a first interface connected to the p probe pins of the probe arm to measure electrical characteristics associated with the IC contacts under test. The probe arm, clamping mechanism, and probe platform work in cooperation to electrically interface any row of the IC contacts with the electrical measurement device.

Claims

1. A universal socketless integrated circuit (IC) electrical test fixture, the test fixture comprising:

a probing platform to accept an IC, the IC having electrical contacts formed on a bottom surface in an array of m rows, where each row includes n contacts, where m is a variable greater than, or equal to 1, and n is a variable greater than, or equal to 1;

a probe arm including p probe pins, where p is variable greater than, or equal to n;

a clamping mechanism to mechanically interface the p probe pins to a row of n IC contacts under test;

an electrical measurement device having a first interface connected to the p probe pins of the probe arm to measure electrical characteristics associated with the IC contacts under test, a second interface to supply a reference voltage, and a third interface to supply a select signal;

a 1-to-p switch having p signal inputs, where each signal input is connected to a corresponding probe pin in the probe arm, the switch having a control input to accept a select signal with at least n possible voltage levels for selecting a signal input in response to the select signal voltage level, and a signal output connected to the electrical measurement device first interface;

wherein the probe arm, the clamping mechanism, and the probe platform work in cooperation to electrically interface any row of the IC contacts with the electrical measurement device; and

,

wherein the electrical measurement device is a curve tracer, where the first interface is a port selected from a group consisting of a collector port (C) and an emitter (E) port, the curve tracer including an unselected port as a second interface supplying the reference voltage to one of the IC contacts, and a base port (B) as the third interface, and where the electrical characteristics of the IC contacts under test are measured with respect to the reference voltage, sequentially in response to the select signals.

2. The test fixture of claim 1 wherein the electrical characteristics of the IC contacts under test are measured with respect to the reference voltage.

3. The test fixture of claim 1 wherein the curve tracer selected port supplies a plurality of electrical stimuli to each selected IC contact and measures a corresponding plurality of electrical characteristics for each IC contact under test.

4. The test fixture of claim 1 wherein the probe arm, the clamping mechanism, and the probe platform work in cooperation to automatically electrically interface every row of the IC contacts with the electrical measurement device, in succession.

5. The test fixture of claim 1 wherein the p probe pins are mounted in the probe arm in a straight row.

6. The test fixture of claim 1 wherein the probe platform includes a temperature chuck to accept a top surface of the IC.

7. A universal socketless integrated circuit (IC) test method, the method comprising:

providing a test fixture including a probing platform to accept an IC with electrical contacts formed in an array of m rows, where each row includes n contacts, where m is a variable greater than or equal to 1, where n is a variable greater than, or equal to 1, a probe arm including p probe pins, where p is a variable greater than or equal to n, and a clamping mechanism to mechanically interface the probe arm probe pins to a row of n IC contacts under test;

mechanically connecting the probe arm probe pins to a selected row of IC contacts under test;

using a switch with p signal inputs to electrically connect each of the IC contacts under test, via the probe pins, to a curve tracer electrical measurement device through a switch output, by using a base (B) port of the curve tracer to supply a switch control signal; and

,

measuring electrical characteristics associated with the IC contacts under test by connecting the switch output to a curve tracer port selected from a group consisting of a collector (C) port and an emitter (E) port.

8. The method of claim 7 wherein the curve tracer unselected port supplies a reference voltage to an IC reference contact.