Presently, an inductor adapted at MMIC (Monolithic Microwave Integrated Circuit) which is used for cellular phone or PHS operates at quasimicrowave range over 800 MHz. However, a W-CDMA (Wideband Code Division Multiple Access) will use about 2 GHz range. Therefore magnetic film devices should be compatible up to 2 GHz. We deposited Co-Pd-Al-O system film using rf sputtering method which is expected for operating at 2 GHz, and investigated the effect of Pd content and magnetic field annealing. When Pd composition is 19, 11k was 118 Oe, and showed flat frequency characteristics until 1.5 GHz. The Q factor (=μ'/μ") was 23.3 at 1 GHz, 6.7 at 1.5 GHz and 1.5 at 2 GHz, respectively. Resonance frequency was 2.9 GHz. Therefore Co-Pd-Al-O thin film could be used at over 1 GHz, and also expected as an inductor material for next generation MMIC.
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