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Figure 7: Examples of automatic probe mark detection. A specific combination of standard geometrical algorithms and AI-based algorithms detects the touch point and
makes the required corrections. The probe used has a diameter of 20µm, while the red mark is approximately 16x12µm.
Automatic warpage compensation be tough and time-consuming. To speed up Summary
and probe mark auto detection and automate this operation, an automatic While traditional prober architecture
Innovations in wafer designs and optical inspection performed before and after remains the standard choice for most
technology are not the only challenge to be the probing can be helpful. wafer products, a different approach
faced when it comes to the development of a On the TH2000, warpage is measured by based on multiple mobile probe cards
wafer prober for production testing. In order a laser surface mapping and automatically can solve many tough challenges in
not to transform testing operations into a compensated. A specific combination testing. Solving these challenges allows
bottleneck in the manufacturing process, the of standard geometrical algorithms and for a complete test at the wafer level
prober should embed as many automation artificial intelligence (AI)-based algorithms of the most complex and innovative
features as possible and be autonomous and has been developed to efficiently and technologies, as well as of those layout
require minimal human intervention. accurately detect the touch point and make designs that break the rules of square-
The need to compensate for possible wafer the required corrections. In order to be die geometries in order to maximize
warpage and the need to detect the mark left able to visually identify the touch, images the yield. Testability issues can be
by the probe on the wafer surface represent are acquired before and after the probe solved for non-square dies, mirrored
two challenges where automation can be touch. At the end, it is possible to see the and uneven geometries, as well as
advantageous. The verification of the wafer result of the identification of the touch by double-sided wafers and multi-stack
planarity is essential before probing to be sure the developed image processing algorithm. wafers, giving a boost to their adoption
of the exact pad position. The adjustment of Two examples of automatic probe mark by the industry.
probing offset and overdrive parameters can detection are shown in Figure 7.

Biography
Luca Fanelli is president and GM of SPEA America, the US-based subsidiary of the automatic test equipment
manufacturer SPEA, that has three branch offices in Tyler, TX, Phoenix, AZ, and Santa Clara, CA. He joined
SPEA in 2006 and has held various positions within the company including managing the entire Semiconductor
Engineering Team. He was later appointed Technical Sales Manager for the North America Sales Team. In
March, 2017 he was appointed as Manager of the entire Semiconductor Division in North America. He received
his MS degree in Electrical Engineering from the Polytechnic of Turin, Italy. Email luca.fanelli@spea.com

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