Mariana Fraga - Evaluation of Piezoresistivity Properties of Sputtered ZnO Thin Films

Version 1

      Publication Details (including relevant citation   information):

        Cardoso, GWA ;   Leal, G;   Sobrinho, ASD ;   Fraga, MA ;   Massi, M. Evaluation   of Piezoresistivity Properties of Sputtered ZnO Thin   Films. MATERIALS   RESEARCH-IBERO-AMERICAN JOURNAL OF   MATERIALS 17 588-592 (2014)

      Abstract:

        Zinc oxide (ZnO) thin films were deposited by RF reactive   magnetron sputtering on silicon (100) substrates under different   experimental conditions. ZnO films were studied before and after   annealing treatment at 600 degrees C. The crystallinity,   electrical resistivity, stoichiometry, thickness, and elastic   modulus of the films were investigated. ZnO piezoresistors were   produced using microelectronics processes, such as   photolithography, lift-off, and reactive ion etching (RIE).   Cantilever method was used to determine the gauge factor, and   measurements of Temperature Coefficient of Resistance (TCR) were   performed on a hotplate. The optimization of the deposition   conditions produced ZnO thin films with controlled stoichiometry   (ZnO), crystalline microstructure (phase wurzite, 002), high   elastic modulus (156 GPa), and low electrical resistivity (0.072   ohm.cm), which are good properties for application as   piezoresistive pressure microsensor. In addition, the ZnO   piezoresistors had a GF of 2.6 on the deformation in the plane   (100) and TCR of -1610 ppm/K up to 250 degrees C.

      Address (URL): http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392014000300008