Laminated substrate with piezoelectric thin film, piezoelectric thin film element and method for manufacturing this element
AssigneesSciocs Company Limited, Sumitomo Chemical Company, Limited
InventorsKenji Shibata, Kazutoshi Watanabe, Fumimasa Horikiri
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Abstract
There is provided a laminated substrate with a piezoelectric thin film, comprising: a substrate; an electrode film formed on the substrate; and a piezoelectric thin film formed on the electrode film, wherein the piezoelectric thin film is made of an alkali niobium oxide represented by a composition formula of (K1-xNax)NbO3 (0<x<1), having a perovskite structure, and oriented preferentially in (001) plane direction, and contains a metallic element selected from a group consisting of Mn and Cu at a concentration of 0.2 at % or more and 0.6 at % or less.
Claims4
A sputtering target material made of a sintered compact represented by a composition formula of (K1-xNax)NbO3 (0<x<1), which contains a metallic element selected from a group consisting of Mn and Cu at a concentration of 0.2 at % or more and 0.6 at % or less,
- wherein a piezoelectric thin film is obtained using the sputtering target material for forming the piezoelectric thin film on a substrate by RF magnetron sputtering method under conditions of a substrate temperature:
- 600° C., a discharge power:
- 2200 W, a charging gas:
- a mixed gas of Ar-gas and O2-gas, a pressure in an atmosphere:
- 0.3 Pa, Ar-gas partial pressure/O2-gas partial pressure=25/1, and a film formation rate:
- 1 μm/hr, the piezoelectric thin film being made of an alkali niobium oxide represented by the composition formula, having a perovskite structure, containing a metallic element selected from a group consisting of Cu and Mn at a concentration of 0.2 at % or more and 0.6 at % or less, having a leakage current density of 500 μA/cm2 or less at the time of applying an electric field of 25×106 V/m in a thickness direction, and having a relative permittivity of 300 or more and 1000 or less when being measured under a condition of 1 kHz frequency.
A sputtering target material made of a sintered compact represented by a composition formula of (K1-xNax)NbO3 (0<x<1),
- wherein a piezoelectric thin film is obtained using the sputtering target material for forming the piezoelectric thin film on a substrate by RF magnetron sputtering method under conditions of a substrate temperature:
- 600° C., a discharge power:
- 2200 W, a charging gas:
- a mixed gas of Ar-gas and O2-gas, a pressure in an atmosphere:
- 0.3 Pa, Ar-gas partial pressure/O2-gas partial pressure=25/1, and a film formation rate:
- 1 μm/hr, the piezoelectric thin film being made of an alkali niobium oxide represented by the composition formula, having a perovskite structure, containing Cu at a concentration of 0.2 at % or more and 0.6 at % or less, having an etching rate of 0.005 μm/hr or less when etching is performed using a fluorine-based etching solution containing hydrogen fluoride at a concentration of 4.32 mol/L and ammonium fluoride at a concentration of 10.67 mol/L respectively, and having a relative permittivity of 300 or more and 1000 or less when being measured under a condition of 1 kHz frequency.
Dependencies are inferred from the claim text.