| Silicon-on-Insulator (SOI), boasting good optical and electronic properties, is the common material of Integrated Circuits (ICs), Micro-Optical- Electronic- Mechanical- Systems (MOEMS) and Planar - Lightwave - Circuits (PLCs), which makes the monolithic integrations of optical, electronic and mechanical components possible. The mature technologies and superior equipments out of ICs can be borrowed to investigate SOI PLCs. Some electro-optical effects of Kerr effect, Franz-Kedysh effect and Plasma Dispersion effect in silicon can be used in optical modulator and electronic-optical switch. So SOI material will play an important role in the coming development of optoelectronic devices.The particularity of large-section rib waveguide with large refractive index difference in SOI results in some special characteristics distinguished from other waveguides, which need elaborate explanation in theory. The large bent radius of the rib waveguide hinders the device performances from improving further, and confines the device to small channel number and simple functions.In this dissertation, the varied characteristics of SOI rib waveguide were investigated, and the calculated results as well as simulated plots in theory were presented. It was the first time that a 3D overlap integral method was used to calculate the transition loss between the rib waveguides and the slab waveguides, in which the effect of the mode distribution in rib waveguides on the coupling efficiency was taken into account.For the first time, an Integrated Waveguide Turning Mirror (1WTM) in SOI was put forward and realized. Using anisotropic etching technology with KOH solution, the mirror surface was very smooth with root square roughness only 5. 19nm, and the mirror was vertical to the wafer surface because of the crystalline relationship. The insertion loss of the IWTM was about 1. 5dB/mirror. The offset between the waveguide and the mirror was responsible for the loss, which could be eliminated with a higher-resolution photolithography technology and more precise control of the etched mirror position. The IWTMs were applied in the fabrication of the optical splitters and arrayed waveguide gratings (AWGs) whose structures were compact greatly.Multimode interference (MMI) coupler in SOI was researched in depth. The on-chip excess loss was measured about l-2dB, uniformity was about 0. 19-1. 48dB in 4x4 MMI. The chip length was about 2cm.The 1x2 MMI was used to substitute for the normal Y-branch to optimize the output characteristics of the 1x4 compact splitter with IWTMs. Thetested results were well agreed with theory values. The on-chip excess loss of the 1x4 splitter based on 1x2 MMI Y branches was tested about 3. 1dB, and the uniformity was about 0. 4dB. Compared with the splitter using normal Y-branch which was with the excess loss about 4. 3dB and uniformity about 1.8dB, the performance was improved markedly. The loss was originated from the offset between the waveguide and the mirrors mostly. 1x2 MMI obtained very good function. Five devices were fabricated in the area of one square centimeter due to the small size.AWG is a crucial component in Dense-Wavelength-Demulti/Multiplex (DWDM) All-Optical-Network (AON). At present, the commercial AWG is on sale oversea, however, the domestic researches are not at high-level. AWG at home does not make any significant breakthrough in experiments.The dissertation focuses on the discussions of AWG design method from the point of view of fabrications. The process tolerance abilities of Silica-AWG and SOI-AWG were calculated in detail.The dissertation explored the compact SOI-AWG development and made a conclusion for the early stage. Under the condition of practical fabrication specifications, Silica-AWGs were made with foundry, which were applicable devices. After the 8x8 Silica-AWG was packaged, all the channels' insertion losses ranged between 4dB and 8.2dB, all the adjacent-channel-crosstalk was below -23dB, and all the nonadjacent-channel-crosstalk was less than -30dB, repect...
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