EQUI-RESISTANT PROBE DISTRIBUTION FOR HIGH-ACCURACY VOLTAGE MEASUREMENTS AT THE WAFER LEVEL

摘要

A test system and test techniques for accurate high-current parametric testing of semiconductor devices. In operation, the test system supplies a current to the semiconductor device and measures a voltage on the device. The testing system may use the measured voltage to compute an ON resistance for the high-current semiconductor device. In one technique, multiple force needles contact a pad in positions that provide equi-resistant paths to one or more sense needles contacting the same pad. In another technique, current flow through the force needles is regulated such that voltage at the pad of the device under test is representative of the ON resistance of the device and independent of contact resistance of the force needle. Another technique entails generating an alarm indication when the contact resistance of a force needle exceeds a threshold.

主权项

1. A method of testing a semiconductor device, the method comprising:
contacting a first pad of the semiconductor device with a plurality of probe needles, the plurality of probe needles comprising a plurality of first needles and at least one second needle, and the plurality of needles comprising tips, wherein the tips of the plurality of first needles are positioned so as to provide equi-resistant paths between tips of the first needles to a nearest tip of a needle of the at least one second needle; providing current through the plurality of first needles; and measuring voltage at the at least one second needle.