Monolithical Integration of Optical Demultiplexer with the High-Performance Photodetectors for WDM Application

• Main Authors: Wei-Yu Chiu, 邱尉育
• Other Authors: Yi-Jen Chan
• Format: Others
• Language: en_US
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/b7waz2

博士 === 國立中央大學 === 電機工程研究所 === 96 === In recent year, the optical fiber communication attracts a lot of the attention due to the several advantages of low optical loss, high data rate and high safety. The Fiber-To-The-Home (FTTH) system will play a very important role in the future. In the FTTH system, the wavelength division multiplexer (WDM) and the photodetector are the key components. We will adopt the novel structure to improve the performance of the photodetector. Besides, the monolithically integration will be used to combine the two independent devices for the decrease of the optical loss and cost. Finally, the photonic crystal technology will be used for more application. In the chapter 2, the partially p-doped absorption layer is adopted to improve the performance of the photodetector. This design can increase the maximum saturation current without sacrificing the responsivity. By integrating a partially p-doped PD with a leaky optical waveguide and the Distributed Bragg Reflector (DBR), the performance of the high responsivity, high saturation current and high frequency response can be achieved. At the same time, the tolerance of the cleaving process can be greatly increased. In the chapter 3, we demonstrate charge compensated uni-traveling-carrier photodiodes (UTC-PDs) by a gradually doping collector. The charge compensated UTC-PD owns the high saturation current and high speed performance. Besides, the single mode propagation waveguide is designed by the BPM software. The novel optical waveguide is also used to construct the WDM. The integrated passive demultiplexer can separate the incoming 1530nm and 1550nm wavelengths, which are near the wavelengths used for transmitting the digital and video analog signals and the signals can be extracted by the photodetectors. In the chapter 4, the silicon on insulator (SOI) PC ring resonator is demonstrated by the plane wave expansion (PWE) [56], and finite-difference time domain method (FDTD). Although the SOI-PC ring resonator is demonstrated for the application of WDM, but there are some problems in the PC resonator. To overcome the problems of the SOI-PC ring resonator, the channel-drop filter is adopted and the nano-resonant cavity can be formed by optimizing the radius of the nano-holes. Finally, the monolithically integration is demonstrated. In the chapter 5, we will give a conclusion in this thesis.