| AbstractWith the rapid increase of global message volume, optical communication system's demand for bandwidth and capacity improves constantly. Wavelength division multiplex technology is capable of realizing large capacity and multifunction. It has great potential in network service application and becomes preferred technologh in optical fiber communication. Arrayed waveguide grating is considered as a kind of new promising device due to its low propagation loss, high wavelength resolution, easily coupled with optical fiber. The components based on AWG represent one of the key enabling technologies for DWDM systems.The arrayed waveguide grating consists of input/output waveguides, two focusing slab regions and a phase-array of multiple channel waveguides with the constant path length difference ΔL between neighboring waveguides. It can work as grating and complete the function of multiplexing and demultiplexing for light with different wavelength. In this paper, we introduced the basic structure and function of AWG, deduced the optical waveguide equations of AWG in theory, summarized the studied progress and application of AWG, and formulized optimized means in performances of the phase error compensation and temperature error compensation and flat spectral response and birefringence control of AWG. Single-mode channel waveguide is the basic element of planar lightwave circuits and integrated lightwave devices. It's the first step of fabricating arrayed waveguides grating to prepare silica-on-silicon waveguides. Based on the optical waveguide theory and combining with our experiments, we designed single-mode transmission condition and waveguide dimension fabricated by flame hydrolysis deposition and reactive ion etching (RIE) or UV-writing technology. For 10GeO2-90SiO2 RIE-etched waveguide, the refractive index of cladding and core are 1.4513 and 1.4639, respectively, and the designed single-mode dimension is 4×6μm2. For 10GeO2-90SiO2 UV-written waveguide, the refractive index of upanddown, left right and core are 1.4513, 1.4639 and 1.4727, respectively, and the designed single-mode dimension is 6×9μm2. This result provides a good foundation for fabrication of Si-based AWG.Silica-on-silicon planar waveguide technology has developed since 1990's, and more attention has been paid to silica waveguide on silicon because of mature silicon processing technique and easy photoelectronic device's integration on a large scale. The preparation of silica-on-silicon waveguide materials is always one of the hard and key steps to fabricate AWG devices. We are the first in China to fabricate 20μm-thickness and 0.1dB/cm-loss SiO2 glass films and 5~40mol% Ge-doped silica waveguide material. We studied emphatically the consolidation of SiO2 and Ge-doped SiO2, and discussed the relations of the refractive index, thickness and the annealing temperature. 10mol% Ge-doped SiO2 is smooth and uniform after annealing at 1150℃ for 2h. It is suitable for core of waveguide with 5μm-thickness and small roughness, 10-6 in the extinction coefficient. Its refractive index at 1550nm is 1.4639, and its loss is less than 0.527dB/cm. In the experiment, we have analyzed the samples by SEM, AFM, XPS, XRD and VASE. It can be concluded that we have fabricated smooth SiO2 and Ge-doped SiO2 glass film. This work is important in China for the research on silica-on-silicon planar waveguide device, such as AWG.The effect of photoinduce refractive index changes in germanosilicate glass by UV writing has a potential advantage in integrated optical circuit and photonics devices. We have studied the photosensitivity of germanosilicate through KrF excimer laser operating at 248nm. The relative refractive index change of 14mol% Ge-doped SiO2 film is 0.341% after exposure followed by hydrogen loading, which approaches to the reported results in this research field. We have obtained the dependence of irradiation time on the refractive index changes through a series of experiments. The positive and negative refractive index change with the...
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