In this paper, two broadband measurement methods, shorted microstrip method and microstrip trnasmission method, are discussed, and the complex permeability of ferromagnetic thin films is measured from 100MHz to 18GHz. The S-parameters of the two measurement fixtures are measured by vector network analyzer (VNA). The perturbations of the thin film loaded in the measurement fixture are analyzed; the discontinuity between coaxial and microstrip is considered; the effective permeability is deduced from measured S-parameters; the permeability of ferromagnetic thin films is extracted from effective permeability by using conformal mapping. The results show that the experimental results agree with the theoretical ones closely, and higher measurement sensitivity and accuracy are achieved by using shorted microstrip method.
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