During the production or thermal treatment of thin layers, stress can arise in the layers. This is caused, for example, by different lattice constants or expansion coefficients of the substrate and of the layer. Also the volume increase by oxidation leads to stress in the layer. Undesirable stress changes can lead to impairment of the function of the parts, partial separation of the layer or cracks in the same and thus to part failure. The measurement of stress is therefore indispensable to control the process parameters and reduce rejects (possibly also before further processing steps).
The MicroProf® is the ideal measuring device for this measurement task: the change in the curvature of the wafer is determined by means of the topography measurement of the wafer before and after the coating. From the radius of curvature, the material data, as well as the thickness of the substrate and the coating, the system calculates local and global stress using the Stoney equation. With the powerful and intuitive Acquire Automation XT software, you control your measuring system, perform fully automatic 2D or 3D measurements and log the results of the measurements in detail. With stress measurement within Acquire Automation XT it is possible to define individual recipes for different wafer sizes and material data. So you are well-equipped for all cases. The MicroProf® as a multi-sensor measuring device also offers a wide range of possibilities for the complete wafer inspection. For example, topography sensors can be combined with layer thickness sensors and the thicknesses of the coatings for stress measurement can thus also be determined directly in a measuring device.
We certainly have a solution for your specific application. Do not hesitate to contact us with any questions. Our experts will be glad to take care of your needs and work out individual solutions for you.