3D measurement of thermal deformations on an ultra-high density circuit moduled with a laser range probe

A laser triangulation range sensor mounted on a coordinate measuring machine was used to measure thermally induced deformations in a circuit module. The module was housed in an environmental test chamber with optical access for the laser probe, and measurements were made over a 25-125 degrees C range with an estimated accuracy of +or-5 mu m. The results clearly show relative 3D displacements of circuit module components which could cause failure of the module under thermal stress.<
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