Development of less than 100µm thick sheet for noise attenuation by electromagnetic induction

High permeability of ferromagnetic materials has been used for noise reduction of the electronic devices. As an effect of noise attenuation of ferromagnetic materials is as a function of thickness, such materials are not suitable for recent trend of thinner package. We proposed to use electromagnetic induction instead of high permeability for noise attenuation that can be suitable for thinner package. We confirmed more than 90% noise attenuation ranging from 0.1 to 6 GHz and 3 to 30 GHz bands by 50μm total thickness of the noise attenuation sheets.