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High frequency high field permeability of patterned Ni[sub 80]Fe[sub 20] and Ni[sub 45]Fe[sub 55] thin films was measured from lithographically defined toroids. Measurement frequency is up to 500 MHz and excitation field up to 5 Oe. Permeability rolloff is calculated from the inductance data. In this experiment, patterned widths range from 30 down to 0.5 μm. Our data suggest that the rotational permeability measured at low field excitation is sufficient to predict high frequency characteristics. The rotational permeability decreases with decreasing patterned width. The 0.5 μm wide permalloy device has μ of 80 and the Ni[sub 45]Fe[sub 55] 50. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]