抄録
This paper was conducted to develop applications using CoFeSiB/SiO_2 composite multi-layer film. For a micro DC/DC convertor, it is necessary to improve the efficiency and miniaturization by incorporating a micro inductor with a high quality factor. High Q values and high inductances of the inductors are compatible with each other when a three-dimensional winding helical coil and composite multi-layered film are used. Furthermore, the decrease of the areas of the inductor and capacitor contribute to miniaturization, as the capacitor is used as the substrate of the thin-film inductor. The frequency response of capacitance was measured to check the frequency noise in a frequency range of 200 kHz 〜 10 MHz and a magnetic field of -76 dBm 〜 8 dBm.