Thin-Film Characterization for High-Temperature Applications

Most thin films produced by a wide variety of methods, either physical or chemical (PVD, CVD, sputtering, etc.) for temperature sensor applications, can be used only in very narrow ranges of temperatures, where their components are not subjected to differential thermal expansions, recrystallizations, and grain size modifications. This paper reports the production and characterization of thin films of platinum and titanium in ceramic substrates by one of the physical vapor deposition techniques, the e-gun evaporation. The choice of materials and the determination of film thickness, density, electrical resistivity, surface roughness, and structural characterization (X-ray, SEM, and AES) are studied. Special emphasis is given to the thermal and electrical behavior of these films between room temperature and 1000°C.