Study On Thin Film Transformer And Inductor

Following the rapidly developing of Information Technology (IT), the electronic systems are becoming more and more complication and integration, which needs more and more microchip components to be integrated on one small area. In order to decrease the volume and weight of the system, one-way is to develop the micro-integrated technology, and another one depends on miniaturizing the components. The transformer and inductor, which are the most important magnetic components, are not only used in RF communication fields but also attracted in integrated with semiconductor devices. They have not been widely used in our homeland. The reason has been attributed to the limited of thin-film material, substrate, process technology and design technology. So, in this thesis, the thin film transformers and inductors are researched by theories and experiments.In researching of thin film transformer, based on theory model and structure of film transformer, we design and fabricated multilayers I type thin film pulse transformers. The serial inductance, equivalent serial resistance, quality factor and insertion loss are measured by At3600. The influence of process parameters and thin film composition on the properties of film pulse transformer has been discussed. The Q factors, inductance, insertion loss presented by us show that the film pulse micro-transformer have good properties in high frequency. In addition, these thin film transformers have not only small size, width frequency range, but also could be integrated in same substrate with other electronic system. Secondly, a model based on artificial neural network (ANN) is set up to imitate the design of film transformer, and it is trained and tested by the data of standard magnetic material manual, which demonstrated that the ANN model can predict the magnetic properties of material quickly and effectively.In researching of thin film inductor, we have adopted the method that calculating of inductance by theories and fabricated inductors by experiments. Firstly, based on the Biot-Savat theory, we set up the computational model of inductors for different shapes, and then use this theory to design our thin-film inductors. Secondly, we have studied the properties of the CoNbZr high frequency soft-magnetic thin film, and use the DC magnetron sputtering system by conquering the key technology to fabricate double-sides thin-film inductors on 10mm* 10mm Printed Circuit Board and 20mm*20mm ceramic board. Finally, we have tested the properties of the inductors, and discuss the influence of frequency , quality factor and inductor value on the thickness of the film and the form of the inductors. According to the value of the testing, we can draw the conclusion that the values of the inductance get from the computation are corresponding with the testing values, and our inductors can be used in high frequency from 1MHz to 1GHz. The new method of fabricate thin film inductor would bring the inductor from three-dimensions to two-dimensions, abd decrease its volume and weight, which is content with the requirement of "small, light and thin" for the devices.