1. Improvement of the piezoelectric response of AlN thin films through the evaluation of the contact surface potential by piezoresponse force microscopy.
- Author
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Signore, M.A., Francioso, L., De Pascali, C., Serra, A., Manno, D., Rescio, G., Quaranta, F., Melissano, E., and Velardi, L.
- Subjects
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PIEZOELECTRIC thin films , *PIEZORESPONSE force microscopy , *SURFACE potential , *THIN films , *KELVIN probe force microscopy , *ALUMINUM nitride - Abstract
Sputtered aluminum nitride (AlN) thin films were characterized by Piezoresponse Force Microscopy (PFM) technique using a methodology to decrease the contribution of the electrostatic forces to obtain a pure piezoelectric response. Our method is based on the sweeping of the DC voltage applied to the Atomic Force Microscope (AFM) tip under a fixed AC field to evaluate the contact surface potential difference (V CPD) between the tip and the sample used to measure the proper AlN piezoelectric coefficient (d 33,eff), minimizing the electrostatic contribution. Kelvin probe Force Microscopy (KPFM) was employed as reference standard technique to measure the surface potential, confirming the reliability of the proposed experimental procedure on ceramic piezoelectric films, and simultaneously overcoming the disadvantages of the KPFM technique. The capability to tune surface potential of materials over a wide range of values opens new perspectives for the design of devices with changeable surface potential. • Piezoelectric response (d 33) of AlN thin films analysed by PFM technique. • PFM analyses performed using two cantilevers with different contact stiffness k c. • High-k c cantilever reduces the electrostatic force contribution on d 33. • New methodology to improve d 33 measurement based on surface potential evaluation. • Better d 33 evaluation utilizing the surface potential method. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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