Abstract:
An object is to reduce the leakage current of a piezoelectric element including a potassium-sodium niobate thin film, enhance the reliability of the piezoelectric element and, in addition, enhance the withstand voltage by including a pair of electrodes and a piezoelectric layer sandwiched between the above-described pair of electrode layers, wherein the above-described piezoelectric layer is provided with at least one layer each of first piezoelectric layer which is a potassium-sodium niobate thin film substantially not containing Mn (manganese) and second piezoelectric layer which is a potassium-sodium niobate thin film containing Mn.
Abstract:
There are provided a thin-film piezoelectric element including a piezoelectric thin film which has an alkali niobate-based perovskite structure represented by the composition formula (K1-w-xNawSrx)m(Nb1-yZry)O3 and which is preferentially oriented to (001), and a pair of electrode films that sandwich the piezoelectric thin film, a thin-film piezoelectric actuator, and a thin-film piezoelectric sensor each including the thin-film piezoelectric element.
Abstract:
A thin film piezoelectric device according to the present invention includes a pair of electrode layers and a piezoelectric thin film interposed between the pair of electrode layers, wherein the piezoelectric thin film contains a rare gas element and has a content gradient of the rare gas element in the thickness direction of the piezoelectric thin film.
Abstract:
An object is to increase the amount of displacement of a thin-film piezoelectric element including a piezoelectric thin film having an uneven-shaped contact surface with the planar shape and the layer structure of the thin-film piezoelectric element kept unchanged. The thin-film piezoelectric element includes a pair of electrode layers and a piezoelectric thin film sandwiched between the pair of electrode layers, in which a surface roughness P-V of an interface between the piezoelectric thin film and at least one of the pair of electrode layers is 220 nm or more and 500 nm or less.
Abstract:
A thin film piezoelectric element according to the present invention includes a potassium sodium niobate thin film having a structure in which a plurality of crystal grains are present in a film thickness direction; and a pair of electrode films sandwiching the potassium sodium niobate thin film. When the potassium sodium niobate thin film is divided into three regions of the same thickness in the film thickness direction and average crystal grain sizes A1, A2, and A3 of the respective regions are determined, a ratio m/M of the smallest average crystal grain size m among A1, A2, and A3 to the largest average crystal grain size M among A1, A2, and A3 is 10% to 80%. The region having the smallest average crystal grain size m lies next to one of the pair of electrode films.
Abstract translation:根据本发明的薄膜压电元件包括具有多个晶粒在膜厚度方向上存在的结构的铌酸钾钠薄膜; 和一对夹着铌酸钾钠薄膜的电极膜。 当铌酸钾薄膜在膜厚度方向上分为相同厚度的三个区域并确定各个区域的平均晶粒尺寸A1,A2和A3时,最小平均晶粒的比率m / M A1,A2和A3之间的尺寸m为A1,A2和A3之间的最大平均晶粒尺寸M为10%至80%。 具有最小平均晶粒尺寸m的区域紧邻该对电极膜中的一个。
Abstract:
A piezoelectric element includes, as a piezoelectric layer, a thin film of potassium sodium niobate that is a perovskite compound represented by a general expression ABO3, in which Ta (tantalum) is substituted on both of an A site and a B site. Accordingly, the piezoelectric element is provided to increase a reliability of the piezoelectric element using the thin film of potassium sodium niobate and to improve piezoelectric characteristics thereof.
Abstract:
A dielectric device has a first electrode film having a non-oriented or amorphous structure, a dielectric film provided on the first electrode film and having a preferentially oriented structure, and a second electrode film provided on the dielectric film and having a non-oriented or amorphous structure.
Abstract:
A piezoelectric element includes, as a piezoelectric layer, a thin film of potassium sodium niobate that is a perovskite compound represented by a general expression ABO3, in which Sr (strontium) is substituted on both of an A site and a B site and Mn (manganese) is substituted only on the A site. Accordingly, the piezoelectric element is provided to decrease a leak current of the piezoelectric element using the thin film of potassium sodium niobate, to increase a withstand voltage thereof and to improve piezoelectric characteristics thereof.
Abstract:
The displacement as an actuator or the sensitivity as a sensor of a piezoelectric element can be increased and, in addition, the electric power consumption can be reduced by providing a thin film of potassium-sodium niobate, which is a perovskite type compound represented by a general formula ABO3, as a piezoelectric layer, wherein a crystal orientation of a crystal structure of potassium-sodium niobate has in-plane fourfold symmetry as a whole piezoelectric layer, where a first axis of rotational symmetry is a thickness direction of the piezoelectric layer.
Abstract:
A thin film piezoelectric device according to the present invention includes a potassium sodium niobate-based piezoelectric thin film having an average crystal grain diameter of 60 nm or more and 90 nm or less, and a pair of electrode films configured to hold the piezoelectric thin film therebetween.