Study of Multiple Micro Cavity Semiconductor Lasers using Strained Quantum Wire Structure

在这项工作中，为了实现通信用长波长半导体激光器的极低电流操作，我们研究了应变量子线激光器的制造和激射特性，这是由于在有源区增加了高光学增益。主要研究结果如下：1）采用电子束光刻技术和两步有机金属气相外延生长技术制备了波长为1. 5 μ m的GaInAsP/InP量子线激光器。测量了量子线激光器的温度依赖性，并与在同一晶片上制造的量子膜激光器进行了比较。结果表明，在低于200 K的温度下，两种激光器的内量子效率基本相同，并且量子线激光器具有比量子膜激光器更好的激射特性，如低阈值电流和高微分量子效率。从理论上分析了多微腔（MMC）激光器在低阈值电流下的静态特性和调制偏斜，并对MMC激光器的结构进行了优化设计。研究了用于光互连的超低阈值电流激光器的驱动电流和设计考虑。3）采用湿法化学腐蚀工艺制备了GaInAsP/InP应变量子阱有源区MMC激光器。在室温下获得了178 A/cm ^2的低阈值电流密度工作，并具有宽接触。4）研究了MMC激光器高反射腔面制作中梅萨角度对条向的依赖性。采用ECR干法刻蚀技术制作了高深宽比的窄槽（0. 45 mm宽）结构。

In this work, to realize extremely low current operation of long-wavelength semiconductor lasers for communication, we have investigated the fabrication and lasing properties of strained quantum wire lasers due to increasing highly optical gain at the active region., and the theoretical analysis and fabrication of the newly proposed multiple micro cavity lasers.Results obtained in this research are as follows.1) 1.5mum-wavelength GaInAsP/InP quantum wire lasers were fabricated by electron beam lithography, and 2-step organic metal vapor phase epitaxy growth. Temperature dependence of the quantum wire lasers were measured and compared with the quantum film lasers fabricated on the same wafer. As the result, at a temperature below 200K,the internal quantum efficiency of the both lasers were almost same, and better lasing properties, such as low threshold current and high differential quantum efficiency of quantum wire lasers over quantum film lasers were confirmed. The reason for poor characteristics temperature of the quantum wire laser was considered to be due to non-radiative recombination at the interface of the quantum wire structure.2) The static characteristics and the skew in modulation of the multiple micro cavity (MMC) lasers were studied theoretically due to the design of the optimum structure for low threshold current operation, and the drive current and design consideration of an ultra low threshold current laser for optical interconnection was also investigated.3) MMC lasers with GaInAsP/InP strained-quantum-well active region were fabricated by wet chemical etching. The low threshold current density operation of 178A/cm^2 with broad contact was obtained at room temperature.4) Stripe direction dependence of mesa angle was investigated for the fabrication of high reflective facet of MMC lasers. The high aspect ratio of narrow groove (0.45mm-wide) structure was fabricated using ECR dry etching.