Wafer Stability, cell-bow & Pull Testing


High throughput and machine uptime combined with a low breakage rate for high production yield is one of the main tasks in present solar cell production lines.
Latest developments show a decrease of wafer thickness in the range of 180 μm and below. Processing these wafers requires intensive knowledge of maximum stability and mechanical strength. During processing, the mechanical stability of a wafer is strongly influenced by mechanical handling as well as chemical and thermal processing.
The new generation of the STAB-TEST with 4 sets of test stages allows for identification of the cause for breakage, bow as well as bad soldering and is the key to improve your production yield.


The new STAB-TEST is specifically designed for performing all types of force/displacement measurements on 156 mm cells and wafers. An extension for 125 mm wafers is available on request. With the Twist- and 4-Point Bend-Test, the STAB-TEST is used for stability testing whenever breakage is observed in the production line, and helps to remedy the cause.
When used with the Pull-Test stages, the STAB-TEST gives worthy information on tabbing adhesion, and becomes indispensable for any module manufacturer. The soldering quality can be tested and observed over the entire cell length under angles of 90°, 135° and 180°.
The Bow-Test stage allows fast and accurate bow measurement to optimize firing and rear side print process parameters.

The new STAB-TEST is a complete redesign. The intuitive new construction greatly simplifies handling and increases system performance. Chucks and setups for the different measurement tasks are more user-friendly and enable faster switch between the operation modes.
Electronic coding of the chuck setups increases usability and reduces operation errors. The new software, which runs on a dedicated control station PC, presents itself with a reworked user interface, additional functionality, and generally makes the system easy to operate.

Improvements on a glance

  • New force measurement principle
    Higher accuracy, failure-safe operation, easier calibration
  • New design, new mechanics, new electronics
    Improved performance, easy operation, easy maintenance
  • New chuck design
    Switch measurement modes in a minute
  • Electronic chuck setup coding
    Software automatically recognizes hardware configuration
  • New software
    Optimum handling of the tool by intuitive operation