The PS21-RF Autoprober, shielded to provide automated RF/microwave measurements, handles 3″ or 4″ GaAs wafers thinned to 100 microns or less. The chuck system features zone-controlled vacuum holes instead of hold-down rings, eliminating wafer breakage and ensuring the best possible heat sinking for thermally sensitive parts.
The patented MicroChamber with an internal ground plane (IGP) provides a probing area with two metal EMI/RFI shields for greater noise immunity. The outer shield protects the probing area from light while shunting interference to chassis ground. The IGP also creates a Faraday cage that functions as a purge box for frost-free thermal measurements. Typical shielding is -40 dB. Typical configuration: $250,000. Cascade Microtech, (503) 626-8245.
Copyright 1998 Nelson Publishing Inc.
May 1998