Pacific Western Systems Model  20 is a space effective manual loading bench top probe module.  The M20 is a cost effective solution for low volume production probe and inspection of semiconductor wafers and hybrid substrates.

The Model 20 uses computer control, gray scale pattern recognition, and programmable lighting for substrate rotation alignment and X-Y motion control.  This compact bench top module has all the power, features, and capabilities of a high-volume production system - at a fraction of the cost.

M20 motion is controlled by PWS' ProbeCommander software.  This advanced prober control environment is a collection of servers and applications designed to simplify the management of probing operations.  ProbeCommander provides high-level software interface and functionality for easier, faster and more robust control of the probe test system.

The Model 20 uses PWS' Air Bearing Motion System for X-Y positioning.  The ABMS is a lead screw driven stage that moves on a frictionless film of air. The stage is supported by air only when moving, and sets on a precision lapped surface plate when at rest. The ABMS is designed for precision stepping of semiconductor wafers.  The ABMS, combined with our in-house manufactured precision lead screws, offers superior accuracy, repeatability, and mechanical stability.

A large support plate is provided for mounting probes, inspection optics, or custom hardware.  The support plate is co-planar to the chuck surface, and can be raised vertically via a three point micrometer lift system.  The support plate has a vertical travel of two inches.  It can be machined exceptionally flat for applications that require precise planar mounting, such as manipulators with RF probes.


  • Gray Scale Pattern Recognition System

  • Programmable Optics Light Source

  • Real Time Wafer Mapping 

  • Three Point Co-Planar Probe Card Support Plate

  • High-performance PC Controller

  • Manual Load Transfer Arm

  • Single Die Alignment Software ( Optional)

  • X-Y Microscope PC Controller (Optional)


  • Stage Travel:

    • 6 Inch Stage:    (6.8 in. X) (10.5 in. Y)

    • 8 Inch Stage:    (8.8 in. X) (10.5 in. Y)

  • Theta Rotation:           +/- 7.5 degrees

  • Chuck Planarization:   +/- .0005 inch

  • Stage Accuracy:         +/- .00025 inch

  • Stage Resolution:       .0001 inch

  • Scanning Speed*:        5 inch / sec.

  • Repeatability:             +/- .05 mils.

* Throughput, stepping, or cycle time are not the same as "scanning speed." Stepping time varies with many factors and is highly dependent upon specific applications. Some factors that affect stepping time are: die size, Z separation, edge turn-around, and acceleration / deceleration. For specific data please contact PWS engineering.

Copyright 2001 Pacific Western Systems, Inc.
Last Updated: November 4, 2003