Method and system for compensating thermally induced motion of probe cards

In combination:

• a probe card for testing a die on a wafer;
• a prober for receiving said probe card for testing;
• a light beam emitter on said probe card for producing a light beam;
• and
• a light beam receiver for receiving said light beam from said light beam emitter to measure deflection of said probe card.

A method of controlling the distance between a probe card and a wafer being tested in a prober, comprising:

• providing a probe card for testing a plurality of die on a wafer;
• providing a prober for receiving said probe card for testing;
• providing a wafer on a chuck in said prober wherein said wafer is positioned for contact with said probe card;
• providing a sensing system for measuring the distance between said probe card and said wafer;
• and,
• adjusting said distance in response to changes in the distance reported by said sensing system.

A method for controlling the distance between a probe card and a wafer in a prober, comprising:

• providing a probe card for testing a plurality of die on a wafer;
• providing a prober for receiving said probe card for testing;
• providing a wafer on a chuck in said prober;
• measuring a first distance between said probe card and said wafer;
• comparing via microprocessor means said first distance to a second distance to determine a variance therebetween;
• and,
• when said microprocessor determines said variance exceeds a determined value, adjusting the distance between said probe card and said wafer.

In combination:

• a probe card for testing a plurality of die on a wafer;
• a prober for receiving said probe card for testing;
• an radiative source for transmitting a signal reporting information proportional to the position of the probe card during testing of the dies;
• and,
• an radiative receiver for receiving said information.