The Research Of A Novel Resonant Cavity Enhanced Dual-Absorption Photodetector

With the development of WDM optical network technology, as one of the key technologies of which, the low-cost and high-performance de-multiplexing and receiving device is the guarantee for the application of WDM technology and the exertion of its formidable functions in practical communication systems. And the high-speed, high-quantum efficiency and narrow-bandwidth photodetector is the major part of high-performance de-multiplexing and receiving device.This dissertation conducted the research work around integrated de-multiplexing and receiving photodetectors in WDM system, the main research work and results were summarized in the following dimensions:1. The optical field distribution in this new resonant cavity enhanced dual-absorption (RCE-PINIP) structure was analyzed. Then the theoretical calculation and simulation of Standing Wave Effect (SWE) were conducted, based on which the influence of SWE on the quantum efficiency (QE) of this structure was also calculated and simulated. A scheme which was used to optimize the quantum efficiency of this structure was proposed.2. According to analysis of the optical field distribution in this RCE-PINIP structure, its quantum efficiency was calculated using transfer matrix method. With the gradual increase of absorption layer thickness in the 50nm-800nm range, there would emerge several QE peaks for this RCE-PINIP structure model. And the QE peak firstly increased (when both single absorption layers were 325nm, QE peak reached the highest value:98.6% at 1550nm) and then gradually decreased. After the optimization of this photodetector, an optimized RCE-PINIP structure was obtained.3. The RCE-PINIP photodetector was successfully fabricated, and the quantum efficiency and high speed qualities were both measured. The experimentally testing results were:the quantum efficiency peak, approximately 70%, was abtained at 1500nm and its 3dB bandwidth was about 2～3G Hz.4. Participated in the fabrication of monolithically integrated long-wavelength four-mirror-three-cavity photodetecor. The FP cavity and spacer cavity with GaAs/AlGaAs DBR and InP-based PIN structure had been integrated on GaAs substrate. The realized photodetector had the quantum efficiency of 58.47% at 1550.3nm, and 0.78nm FWHM; its 3dB bandwidth was 8.1 GHz when tested under 6V reverse bias voltage.