Influence of seed layer on crystallinity and orientation of pulsed — DC sputtered AlN thin-films for piezoelectric actuators

Aluminum Nitride thin films with the desired properties for piezoelectric actuators are grown by pulsed DC sputtering on Si (100) substrates coated with different seed layers (Al/1%Si, Mo, Ti). The influence of sputtering parameters and the seed layers on crystallinity and orientation of the AlN films is investigated. Raman spectroscopy measurements are performed and the results are analyzed to identify the optimal deposition conditions. The high-cc axis orientation of AlN thin films obtained with Ti as a seed layer was confirmed by X-ray diffraction. It appears that seed layers of 200 nm Ti are a valid alternative to Molybdenum or Platinum for IC compatible piezoelectric actuators fabrication.MicroelectronicsElectrical Engineering, Mathematics and Computer Scienc