Ultrafast laser micromachining and patterning of thermal spray multilayers for novel sensor fabrication

Fabrication of structural and functional parts and components, especially at the micro and nano scales, is crucial to a wide range of applications in the electronics, communications, medical, aerospace, and military industries. This work presents an innovative conformal direct-write technique for rapid prototyping and manufacturing novel sensors. The technique combines thermal spray, which, as an additive process, produces blanket depositions of films and coatings, with ultrafast laser micromachining, a subtractive process to produce functional patterns. Several kinds of sensing components, such as microheaters and strain gauges, have been successfully fabricated in this work with thermal spray technology and a femtosecond laser, which demonstrates the feasibility and advantages of the proposed technique. The electrical and thermal property characterization of the sensors was also performed, and shows promise for sensors in micro-sensing systems. With minor modification to pattern design and processing procedures, various sensing structures and electronic components, for example, precision resistors and interdigitated capacitors, can be readily fabricated using the presented technique.