Based On Mems-saw Device Design And Production Of Key Technologies

Due to its unique advantages such as high frequency, low volume, versatility, stability and mass production, the surface acoustic wave (SAW) device become one of the three families of solid microelectronic devices, in parallel with the LSI and the CCD. Nowadays it is widely used in military and civilian fields including aerospace, mobile communication and electronic counter-measure, etc. The newly arisen SAW device is promising and gaining more and more attention for its passiveness, wirelessness, high sensitivity and low power consumption.The contents of this thesis include the following:Interdigital transducer(IDT) is the basic structure of SAW devices. The genetic algorithm is adopted to optimize the amplitude-frequency response characteristics of the IDT, according to its time-domain discretization characteristics and limitations on fabrication accuracy. Encoding of the sound aperture of the IDT is completed, and the function of sufficiency is proposed. The new design does improve the amplitude-frequency response characteristics of the IDT.The three-IDT SAW band-pass filter is designed, followed by a discussion of effects of different window functions on the characteristics of the interdigital transducer.The design of the SAW accelerometer with a structure of triangular projecting beam is analyzed. Details are given to the relations between the sensitivity of the transducer and the isogonism and thickness of the projecting beam.Fabrication is the bottleneck of SAW technology. Sputtering and etching are key processes in fabrication of SAW devices. Experiments are conducted to find the influence of some process parameters on the sputtering rate. The relations between some factors and the rate of inductively coupled plasma etching are studied, and so are the speed ratio and uniformity of etching.