Tensile test of lead zirconate titanate (PZT)/Platinum (Pt) thin film

Abstract

This paper presents the results of tensile tests for lead zirconate titanate (PZT)/Platinum (Pt) thin films of 2.15 lm thickness in atmospheric air at room temperature. An axial loading tester developed by the authors was used for the tests. The tester was equipped with a load cell with a maximum capacity of 0.5 N and a non-contact position measuring system based on the principle of capacitance micrometry. Furthermore, the tester was equipped with a CCD (chargecoupled device) system for measuring the displacement of the gage length. Specimens with three different widths (50, 100 and 150 lm) were fabricated to study the size (width of specimen) effects. The elastic moduli of the specimens with 50, 100 and 150 lm width were 72.8 € 3.7, 75.0 € 1.3, 73.3 € 1.8 GPa, respectively. In addition, the ultimate tensile strength of the specimens with 50, 100 and 150 lm width were 263.4 € 21.1, 238.6 € 4.5, 221.1 € 13.9 MPa, respectively. It was observed that the width of specimen has little effect on the elastic modulus of PZT/Pt thin films but has an effect on the ultimate tensile strength of PZT/Pt thin films and the ultimate tensile strength decreases as the width increases. It was assumed that the scatter in the ultimate tensile strength of 50 lm width was attributed to delamination of PZT/Pt layers before the fracture in the tensile test. The 0.2% offset yield strength could not be measured because the PZT/Pt thin film is very brittle.Keywords: Lead zirconate titanate thin film (PZT) / platinum (Pt) / micro tensile test / tensile strength / elastic modulus / thin film / Schlüsselwörter: dünne Blei-Zirkonat-Titanat (PZT) Schicht / Platin (Pt) / Mikrozugversuch / Zugfestigkeit / elastischer Modul / dünne Schicht /

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