Although the pitch between bonds reduces year on year, the challenges of meeting this demand has fallen on other processes more than the science of bond testing. With industrial bonding at 50μm becoming common place, this is no longer the case. Wire bonding at 25/μm and below is proven in laboratories, including the shear and pull testing of these wires. Although it is possible to use existing testers at these geometries, their ease of use and accuracy is being pushed to, if not beyond, their limits. In order to accurately test and measure these finer pitches, equipment manufacturers have to address a series of issues such as: 1. Lower ranges of force measurement, 0 to 25grams force with no proportionate loss of accuracy 2. Improved optics and illumination to enable easy alignment of the tool to the sample and grading of the failure mode 3. New tool designs optimised for the changing shape of ultra fine pitch bonds and the relative increase in thickness of the passivation layer 4. Improved step back accuracy when shear testing 5. Anti-vibration measures to maintain accuracy and optical performance with typical environmental conditions 6. Improved control and accuracy of the sample and tool manipulation.
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