【作者】 杨威；

【导师】 李建军；

【作者基本信息】 北京工业大学 ， 微电子学与固体电子学， 2012， 硕士

【摘要】 聚合物光纤在局域网与光纤入户中的应用研究，逐渐进入实用阶段。由于无法得到在聚甲基丙烯酸甲酯PMMA（polymethyl methacrylate）最小吸收的波长470nm附近的低成本光源，在其第二小衰减波长650nm附近的低成本光源成了最佳选择。共振腔发光二极管（RCLED）具有光谱线宽窄，发射方向性良好，发光强度高，无阈值，低成本等特点。RCLEDs在性价比方面介于半导体激光器和半导体发光二极管之间的一个很好的折衷，成为PMMA塑料光纤通信系统的最佳理想光源。随着RCLED研究的不断深入，性能的不断提高，市场对RCLED的各方面性能提出了更高的要求。本文对RCLED进行结构优化，包括电极结构和氧化限制结构，以提高RCLEDs光电性能；并对频率响应进行研究，理论分析RCLEDs的本征调制带宽和寄生参数对带宽的影响，提高RCLEDs调制响应特性。本论文主要从以下几方面展开研究工作：对RCLED的概念、微腔效应、介质层中偶极子的非自发辐射、Purcell效应等方面进行了系统的介绍。阐述了RCLED设计中需要遵循的6个基本准则。采用薄膜光学理论的传输矩阵模型分析DBR的光学性质，用MATLAB模拟计算了影响DBR反射率的主要因素，包括组成DBR的对数和组成DBR材料的折射率差。并对外延片的上下DBR的反射谱进行光学模拟。对RCLED电极结构进行优化，设计了两种电极结构，单环电极结构A和双环电极结构B。对关键工艺选择性湿法氧化进行研究，讨论影响氧化速率的因素，实验并确定了适宜氧化条件。成功制备了两种电极结构的氧化限制型RCLEDs。器件测试与分析，80μm出光孔器件，20mA下最大光功率由单环电极结构A的器件获得，为1.228mW。在小电流下，器件的热效应不显著且电极A有较大的出光面积，电极A器件的光功率比电极B器件高；在大电流下，器件热效应比出光面积的影响要大，电极A器件的光功率比电极B器件小。电极A器件会由于热效应而导致可靠性较差，但是在小电流注入下，其光功率较大。以单环电极为电极结构，对RCLED氧化限制结构进行优化，实验成功制备3种结构器件，90μm，110μm，无氧化结构。对器件进行测试，分析讨论氧化孔径对RCLEDs光电性能影响。最大光功率由无氧化结构获得，为1.909mW。氧化孔径越小，有源区有效电流密度越大；氧化孔径小的器件比氧化孔径大的器件峰值光功率小，因为氧化孔径小，会导致较大的电流密度和较大的串联电阻而产生大的焦耳热，使注入电子以非辐射方式释放其能量；氧化孔径越小，热效应越显著，达到光功率饱和快。研究了RCLEDs的调制响应特性。详细介绍了RCLEDs的本征调制响应理论和提高本征调制的措施，并对RCLEDs本征截止带宽进行模拟，氧化孔径越小，RCLEDs本征截止带宽越高。分析了RCLEDs的寄生参数对调制带宽的影响，主要是氧化孔径对带宽的影响。更多还原

【Abstract】 Polymer optical fiber has got wide concern of the global optical communicationexperts and related enterprise in the application of the local area network and “fiber-opticinto door”, and gradually has been into the practical stage. Since it is difficult to achievelow-cost lighting source at470nm, which is the PMMA POF’s lowest attenuationwavelength. The lighting source at650nm, which is the second lowest attenuationwavelength, could be the best choice. Resonant cavity light emitting diodes (RCLEDs)have many advantages, such as spectral purity improvement, directionality optimization,output power enhancement, zero threshold, lowcost. RCLEDs could be a goodcompromise in price-performance between semiconductor lasers and semiconductorLEDs, and serve as the best lighting source of PMMA POF communication system.With the deepening research and continuous improvement of the performance, themarket has put forward higher request for RCLEDs on all aspects of performance. Thisdissertation focuses on structure optimization to improve the electrical and opticalproperties of RCLEDs, containing electrode structure and oxide-confined structure, andfocuses on the research of frequency response to improve dynamical property ofRCLEDs, theoretically analyzing intrinsic modulation bandwidth and parasiticparameters on the effect of bandwidth. Main research contents in this dissertation are asfollows：A systematic introduction for RCLED has been made from all aspects, such as theconcept of RCLED, microcavity effect, Purcell effect, the spontaneous radiation of dipolelayer in the medium. Six design priciples for RCLEDs has been stated.According to transmission matrix model of optical thin film theory, the maininfluencing factors on the reflectivity of DBRs has been calculated using MATLAB,containing the pairs and the refractive index difference of DBR. The optical simulation ofreflection spectrum for p-DBR and n-DBR of epitaxial wafers has been maded.Electrode structure optimization was made, and two types of electrode structurewere designed, containing electrode structure A with single ring and electrode structure Bwith double rings. Research on the key technology selective wet oxidation was made, theinfluencing factors on the oxidation rate were discussed, and appropriate oxidationcondition were confirmed by experiment. The oxide-confined RCLEDs with two types ofp-electrode have been fabricated and tested. At20mA and with diameter of emittingaperture80μm, the higher light output power1.228mW was abtained by the RCLEDs with the single ring electrode. At low current, since the influence of heat effect on thedevice performance is not obvious and electrode A has greater light extraction, the lightoutput power of RCLED A is higher than that of B. At high current, as the influence ofheat effect is dominant as compared with light extraction and electrode A has greater heateffect, the light output power of RCLED A is lower than that of B. In conclusion,RCLEDs with the single ring electrode has worse device reliability for great heat effectbut greater light output power at low injected current.With the single ring as electrode, oxide-confined structure optimization was made.Three types of structure devices were successfully made and tested, which were90μm，110μm，and nonoxidation structure. The influence of oxide-aperture on the electrical andoptical properties was analyzed and discussed. The maximum optical power1.909mWwas abtianed by nonoxidation structure RCLEDs. The RCLEDs with samlleroxide-aperture have larger injected current density, greater series resistance resulting inhigher voltage and more Joule heat, and more rapidly reached optical power saturation.The maximum output power of smaller oxide-aperture devices is lower than that of largeroxide-aperture devices. It is because that larger current density and greater seriesresistance could lead to greater Joule heat, which results in more injected electronsrelaxing their energy by the way of nonradiation.Modulation response characteristics were studied. A systematic introduction for theintirnsic modulation response theory and the measures for improving the intirnsicmodulation for RCLEDs were made. Simulation of intirnsic cut-off bandwidth was madefor RCLEDs, the RCLEDs with with samller oxide-aperture had larger intrinsicmodulation bandwidth. The effects of parasitic parameters, which were mianlyoxide-aperture, on the modulation bandwidth were analyzed.更多还原