Manufacture Of High-power And High-speed Optical Waveguide Photodetector

A high power and high speed photo waveguide detector is a critical component for optically controlled phased array radar, high-speed test system and local optical fiber communication system. The Thesis works about the manufacture of UTC-VDCPD(Uni-Traveling-Carrier Vertical Directional Coupling Waveguide Photodetector). A vertical directional coupler strcture is explored to trade off the high power and high speed.This thesis deals with a systematic work about waveguide photodetector which includes the waveguide foundation theory, testing platform, fabrication technology and challenge in the manufacturing process. The main works are described as follows:1. Design of the high power and high speed photo detectorThe basic principle of high-power and high-speed photodetector, the structure parameters, thickness and material of waveguide detector’s each layer, details of the substrate after the growth, the adverse effects of various defects on the surface of the substrate are introduced and analyzed.2. Production process of the InP substrated waveguide detectorThe thesis introduces production process of the InP substrated waveguide detector. Referring to the special structure of the device, the design and optimization of photolithography mask layout, according to the machining accuracy and material constraints, and various parameters of front-end input waveguide, coupling layer, the upper left electrode, and mask alignment marks, are designed.3. Fabrication of the detectorThe thesis introduces also the fabrication of the detector. It is firstly performed to verify the process and debugging process in lithography on Si substrate; then complete the debugging on the InP substrate(the width, the angle and the etching rate, etc.) to verify the alignment of lithography process, and processing on formal substrate(including making photolithography, ICP etching and making the electrode). The thesis introduces and analysis the each step of lithography process, developing, etching, lithography, exposure and etching metal electrode in detail. The cleaning and impurity of the etching process and the cleavage of the device in the end process are also presented.4. Device testAfter the completion of the device fabrication, the detoctor must be tested. The thesis presents the I-V data of photo diode. And a test platform is designed for the follow optical test work.Finally the thesis summaries the difficult problems of optical waveguide detector in the manufacturing process and solutions, and the processes of the fabrication. The works done lay a foundation for following researches on the next generation of phtodetector.