Laser patterning of thin film sensors on 3-D surfaces

Thin film strain sensors applied directly on machine components provide high reliability. However, sensors patterned by standard photolithographic processes are limited to planar surfaces. To overcome these limitations we developed a 3-D capable direct patterning process for NiCr thin film sensors based on ultrafast lasers and galvanometer scanners. Our investigations showed that strain sensors with spatial resolution of 30 μm can be patterned on 3-D shaped machine tool components even at extremely tilted surfaces (up to 70°). First machining results and sensor tests indicate that laser thin film patterning enables efficient and automatable production of novel sensor concepts, e.g. for automotive, medical and machine tool applications.