| 摘要 |
PURPOSE:To accomplish formation of a coil conductor of thick film while preventing under etching, and to obtain a high frequency coil having improved quality factor by composition a coil conductor layer of a plurality of thin metallic films and etching each film with different etchant. CONSTITUTION:A coil conductor 3 is formed in two-layer structure composed of a first conducting layer 7, which is formed on an insulated substrate 2 by thin-film forming technique, and a second coil conducting layer 8 which is formed on the upper surface of the coil conducting layer 7. The above-mentioned first and second conducting coil layers are constituted by forming a second Ti-Ag metal thin film on the upper surface of a first Ti metal thin film, and also by forming a third Ag metal thin film on the upper surface of the second metal thin film. The above-mentioned metal thin film are formed by the thin-film forming technique such as vapor deposition, sputtering, ion plating and the like, and the metal thin films are also formed by etching the part other than the coil conductor 3 using a different etchant for each metal thin film. |
