Microfabrication Of Solenoid-Type Microinductor With Magnetic Core By MEMS

With continuously development of information technology, the electronic product is developing towards to higher level in integration and miniaturization. The final destination is to realize all kinds of function units on a single chip, which is an important compotent of electronic circuit called SOC (System On a Chip). As an important componet of elctronic circuits, integration and miniaturization of inductor is becoming the key to realize the electronic products with high performance and small size.Power management chips such as DC-DC convertors which are applied in portable electronic products, are developing towards to higer performance and smaller size. It promotes a great demand for microinductor with high performance in the market, such as the small size, high inductance, high Q-factor, high saturated current and process compatibility.Rapidly development of MEMS technology provides the feasibility of integrated microinductors, The microinductors fabricated by MEMS technique combined with thin film technique should have advantages of low resistance, high inductance, high Q-factor, high efficiency, low loss, low product cost and batch fabrication, which will be extensively applied in power management system.Key work and conclusion of this thesis are listed as below:(1) Performance mesasurement of the mangnetic core material.Measure the magnetic performance of FeCuNbSiB ribbon with the VSM and Agilent E4991A RF impedance/material analyzer after annealing at different temperatures.(2) Simulation of the solenoid microinductor with magnetic coreEstablish the lumped element model for solonoid-type microinductor on the basis of electromagnetic theory. Use the Matlab software to simulate the influence of geometrical parameters and material characteristics on the performance of microinductor. (3) Fabrication of solenoid microindctor with magnetic coreUse MEMS techniques such as lithography, electroplating, magnetron sputtering, dry/wet etching and polyimide technique to fabricate the microinductor with Fe based nanocrystalline thin ribbon and NiFe film respectively.(4) Measurement and analysis of solenoid microinductor with magnetic coreUse the HP 4194A and E4991A RF impedance/material analyzer to test the performance of microinductor in the frequency range of 1-10MHz. The results show that FeCuNbSiB nano-crystalline ribbon annealed at 500℃annealing is suitable for magnetic core. It can help the solenoid microinductor to get high performance of inductance and Q-factor which is better than that of NiFe film.