The study of the permeability spectra of MgCuZn ferrite for near field communication application

NFC technology has been widely used in machine short distance transmission and has gradually become the standard configuration for mobile phones in recent years. To the inductive coupling communication mode, the metal shell of mobile phone batteries will induce a signal that offsets the magnetic field. This finally results in a reduction in communication distance and even invalidation. Inserting a piece of electromagnetic shielding sheet (ESS) between the antenna and the battery is an effective and economic solution. The material for the ESS requires a high real part and a low imaginary part of complex permeability, as well as a high Q factor at the frequency of 13.56MHz [1]. NiCuZn ferrite has been used widely as materials for ESS due to its excellent magnetic properties [1]. But the price of the raw material NiO is very high while the demand of the electromagnetic shielding sheet is extremely large. So, it is necessary to find much less expensive materials to replace the NiCuZn ferrite. MgCuZn ferrites might be an ideal candidate material due to their high permeability at MHz frequencies, and chemical stability [2]. However, according to our investigation, there is no report focused on studying the magnetic properties of the MgCuZn ferrites at the frequency of 13.56MHz.