We hane investigated a new ferrite-ceramc composite material with inductive and capacitive properties fahcicated by a solid-state reaction method. We analyse the effects of the composite mechamism and microstrocture on the magnetic and electric properties. The resuits show that the new materials can be used not only as in ductor materials. but also as capacitor materials in the wide frequency range of 1kHz-1.8GHz. The real part of permeability of the composite material is between 10 and 5.6, the imagimary part of permeability is between 1.2 amd 0.5, and the dielectric constan isabout ten times larger than that of ordinary ferricte materials. It is suggested that the new composite materials will be widely used in anti-electromagnetic interference fields and radio frequency communication fields.

A microchip thin film transformer which is composed of an I-shaped [CoZrNb/SiOχ]m magnetic layer and wound with Cu thin film coils fabricated by using a mask vacuum evaporation and sputtering composited process has been investigated. Comparing the CoZrNb core with [CoZrNb/SiOχ]m core of thin lm transformer, it is shown that the multilayer thin films have more advantages than a single magnetic layer in their of soft magnetic properties, especially the permeability (μ) and coercivity (He). The microchip transformer has a relatively high inductance of 0.4-1.0μH for a ratio of primary turns to secondary coil turns of 3:1 and 3:2, and has a high Q value of 4-12. The thin film transformer can be operated in an integrated micro-switching converter at a frequency between 1kHzand 10MHz.

A new thin "lm transformer which is composed of an E-shaped CoZrRe magnetic layer and wound with Cu thin" lm coils fabricated by using a mask vacuum evaporation process has been investigated. The ratio of primary coil turns to secondary coil turns is 3:1 and 3:2. The transformer has a relatively high inductance of 0.4-0.8μH, and can be operated in an integrated micro-switching converter at frequencies between 100KHz and 10MHz.

The nitrogen ions were implanted in 17pm thick soft magnetic ribbon at a dose range between 1019 and 1021 ions per square metre. The implanted samples were annealed at about 655K for 1h in a vacuum (0.1Pa). The result showed that the effective permeability increased and the coercivity decreased with implanted dose increasing in the frequency range of about 50KHz to 8MHz, whereas the soft magnetic properties deteriorated when the implanted dose was low-1018 ions per square metre, which may be related to finely dispersed metal-N precipitates, the metal-N phase could act as nucleation or pinning sites, suppressing the growth of a-Fe grains and increasing the nucleus formation.

In order to linearize a spin-valve giant magnetoreslstance head, the exchanges layer sputtered at fringe area or a permanent magnet layer longitudinal biasing for domain stabilization based on a physical calcalated mode/may be considered. The corre/ations between the head performance characteristic and head geometric parameters have been simulated by putting the head on a suitable front-end electric circuit. The simulative results show that the optimal sensing current is from 10 to 40mA and the near geometric parameteres for gap width are at the range of G1+G2<0.5μn.