摘要 |
<p>A test apparatus for applying shear loads to a deposit on a substrate comprises a cantilevered shear tool (18) having a tip (24) for contact with the deposit, and a back face having a piezo-electric crystal thereon. In use, the back face is subject to a compressive force, as well as other forces, and a corresponding electrical output from said crystal which is proportional to those forces. In one embodiment, the portion of the shear tool which contacts the deposit is offset rearwardly from the front face of the shear tool to improve the accuracy of the signal produced by the piezo-electric crystal. The apparatus is useful in testing the strength of bonds between deposits and substrates typically found in semiconductor devices.</p> |