The Theory And Experiment Study Of Making The Chip Of FOG By Using Annealed Proton-exchange

Many scientists and military authority attach importance to the FOG because of its advantages, such as smaller volume, simple structure, higher sensitivity and higher start-up speed. The chip of the FOG(Y-branch waveguide phrase modulator) is the pivotal parts in the FOG system, and researching its fabricating technics for improving its performance is very important to our national defence. The main purpose of this subject is to study the principle of the process of annealed proton-exchange and characteristics of the waveguide made by using annealed proton-exchange, and the most important task is to reseach the technics of make the chip of FOG by annealed proton-exchange. At the beginning, the essentiality of the Y-branch waveguide in FOG syetem and design ways of its normal structures are analyzed concisely. Analysis methods of transmission modes in channel waveguides and the design of modulation electrodes are discussed. Different effects of electrooptic modulation caused by different cut direction are reseached, and the relations among the modulation bandwidth, the half-wave voltage and parameters of the structure of modulation electrodes are studied. The principle of the process of annealed proton-exchange is expatiated, and the question " how to recovery the electrooptic coefficient of LiNbO3 " is answered also. The relation between the varity of the depth of APE waveguide and parameters of APE process is deducted by Arrhenius law. In this paper, the principle and the process of Ti-diffusion are illustrated briefly also. the technics of making waveguide by using annealed proton-exchange is discussed as a pivot, and it is compared to the technics of Ti-diffusion. The advantage of making the chip of FOG by using annealed proton-exchange is explained. A new method of eroding aluminium film, through combining two steps of developing and eroding, is created in this paper. Based on theory analyses, a proper technics of making the chip of FOG (Y-branch waveguide) by using annealed proton-exchange and its betterment plan are offered in this paper, and many applied experiment tools are designed. A lot of experiments of making APE waveguides have been done, and all technics parameters of all steps are optimized and confirmed, including spattering, coating, microphotolithographic, exposure, development, eroding, proton-exchange and annealing. At last, the condition of fabricating the single mode waveguide is ascertained.