EG 4085

The Electroglas EG 4085 is an automatic wafer prober. The EG 4085 is manufactured by Electroglas. The EG 4085 is categorized as Test & Probe equipment.^[1][3][4]

The EG 4085 is configured for 8-inch wafers.^[2][1]

An automatic wafer prober moves a wafer into position beneath a probe card. Probe needles on the card touch the bonding pads of each device, and an external tester supplies stimulus and measures response. The prober steps to the next die after each test. An automatic prober also handles wafer loading, flat or notch alignment, and indexing.

A wafer prober of this class uses a precision positioning stage, a theta adjustment, and a z-axis movement to bring the wafer and probe card into contact. Wafer probers often include prealignment optics and pattern-recognition systems so that probe tips land consistently on contact pads.

Wafer probing takes place after front-end wafer processing and before wafer thinning, dicing, and packaging. Probing is the initial electrical test of completed die at wafer level. A prober of this class is used during wafer sort, in which defective die are identified before assembly. The resulting test data can be used for yield management and process control.

Automatic wafer probers serve in wafer-level electrical test and in parametric monitoring during process development. The same equipment supports reliability characterization and failure analysis by exercising individual die before assembly. The test results can be compiled into wafer maps that guide subsequent dicing and binning.