| 发明名称 | Thin-film piezoelectric resonator and thin-film piezoelectric filter using the same | ||
| 摘要 | A thin-film piezoelectric resonator including a substrate (6); a piezoelectric layer (2), a piezoelectric resonator stack (12) with a top electrode (10) and bottom electrode (8), and a cavity (4). The piezoelectric resonator stack (12) has a vibration region (40) where the top electrode and bottom electrode overlap in the thickness direction, and the vibration region comprises a first vibration region, second vibration region, and third vibration region. When seen from the thickness direction, the first vibration region is present at the outermost side, the third vibration region is present at the innermost side and does not contact the first vibration region, and the second vibration region is interposed between the first vibration region and third vibration region. The resonance frequency of the primary thickness-longitudinal vibration of the vibration region (40) is f1 at the first vibration region, is f2 at the third vibration region, wherein f1 and f2 satisfy a relationship of f1<f2, and is a value between f1 and f2 at the second vibration region, said value increasing from the outer portion contacting the first vibration region to the inner portion contacting the third vibration region. | ||
| 申请公布号 | US8854156(B2) | 申请公布日期 | 2014.10.07 |
| 申请号 | US201013202442 | 申请日期 | 2010.02.17 |
| 申请人 | UBE Industries, Ltd. | 发明人 | Iwashita Kazuki;Tsuchiya Hiroshi;Tanaka Kensuke;Maruyama Takuya |
| 分类号 | H03H9/15;H03H9/54;H03H9/17;H03H9/02;H03H9/60;H03H3/02 | 主分类号 | H03H9/15 |
| 代理机构 | Frommer Lawrence & Haug LLP | 代理人 | Frommer Lawrence & Haug LLP ;Santucci Ronald R. |
| 主权项 | 1. A thin-film piezoelectric resonator comprising: a substrate; a piezoelectric resonator stack formed on the substrate and having a piezoelectric layer and top and bottom electrodes formed so as to face each other through the piezoelectric layer; and a cavity or an acoustic reflection layer formed between the substrate and piezoelectric resonator stack, the piezoelectric resonator stack having a vibration region where the top and bottom electrodes overlap each other as viewed in the thickness direction of the piezoelectric resonator stack, the vibration region including a first vibration region, a second vibration region, and a third vibration region, as viewed in the thickness direction of the piezoelectric resonator stack, the first vibration region being located at the outermost side, the third vibration region being located at the innermost side and not contacting with the first vibration region, and the second vibration region being interposed between the first vibration region and third vibration region, the resonance frequency of the primary thickness longitudinal vibration of the vibration region being f1 in the first vibration region, being f2 in the third vibration region, wherein f1 and f2 satisfy a relationship of f1<f2, and being a value between f1 and f2 in the second vibration region, the value increasing from the outer portion contacting the first vibration region to the inner portion contacting the third vibration region, the piezoelectric resonator stack having a support region located outside the vibration region as viewed in the thickness direction of the piezoelectric resonator stack and a buffer region located between the vibration region and support region as viewed in the same direction, and contacting the substrate in the support region, the bottom electrode having, in the support region, a support portion extending along the boundary between the support region and buffer region, and the width w1 of the support portion and thickness t of the piezoelectric resonator stack in the vibration region satisfying a relationship of 2.17≦w1/t≦10, and the width w2 of the buffer region and thickness t of the piezoelectric resonator stack in the vibration region satisfying a relationship of 0.25≦w2/t≦2. | ||
| 地址 | Yamaguchi JP | ||