The probers are used to make electrical connections to the devices on the wafer. The typical probe pad on the ECE444 mask set is 100 μm on a side.

The probe stations consist of

• stereo-microscope
• vacuum chuck for holding the wafer mounted on an x-y positionable stage
• fiber optic illuminator
• probe platform with z adjustment for holding micromanipulators
• four Signatone S-725 Micropositioners
• switch plate for connecting the probes to the measuring instruments
• Agilent 4155C Semiconductor Parameter Analyzer (SPA)
• Agilent 4284A Precision LCR Meter

Micropositioners are used for positioning the tungsten probe tips. The positioners have ~25μm positioning resolution in x, y, and z, and the probes have a tip diameter of 5μm. The probe tip holders are spring loaded to minimize damage to the probe pads, as well as minimize damage to the tips from excessive pressure when applied to the pads.