Research On InGaAsP Multiple Quantum Well (MQW) Lasers

With progress in society and technology, the demand on information service is increasing rapidly. The operation and development of society increasingly depend on information resources. Optical communication technology is one of the most promising technologies in the future for its characteristics of ultra-high speed, high-capacity, integration, low cost, and high reliability, such as Automatically Switched Optical Network (ASON), Fiber To The Home (FTTH), Dense Wavelength Division Multiplexing(DWDM) and so on.Semiconductor lasers are important optical communication devices. Quantum-well lasers with characteristics of low threshold current have been developed rapidly. Multi-quantum-well semiconductor laser based on InGaAsP was studied in this thesis, which works at 1550nm. The research of laser technology will pave the way for future research in our laboratory. The contents of this dissertation are summarized as follows:1. The method and features of the semiconductor laser are researched, including Fabry-Perot(F-P) semiconductor laser of the threshold current, the square distribution, etc. At the same time the model is built up and the influence of well thickness and cavity length on quantum well laser is presented.2. Participated in the designof1550nm FP InGaAsP multi-quantum-well laser and part of the fabrication technology of semiconductor laser is investigated.The F-P ridge structure of this quantum-well laser is designed. Then the material is grown and adjusted by Metal Organic Chemical Vapor Deposition (MOCVD) and epitaxial wafer is grown. Then the InGaAsP multi-quantum-well lasers are fabricated. The test results of InGaAsP multi-quantum-well lasers achieve the desired design requirements:The threshold current is about 10mA, and quantum efficiency is about 14.5%.3. The modeling of the 1550 nm InGaAsP multi-quantum laser is simulated. The simulation procedure includes the adjustment of the laser structure, material composition, doping, etc. After the study on simulation and optimizing parameters of the device, we get the results of the laser includes PI curves, quantum efficiency, etc. Through simulation process, the most important part is the influence of different quantum well thickness on threshold current and quantum efficiency.