國立臺灣大學電子工程學研究所林浩雄2006-07-262018-07-102006-07-262018-07-102003-10-31http://ntur.lib.ntu.edu.tw//handle/246246/19978本計畫包括以固態源分子束磊晶機在砷化鎵基板 上成長銻砷化鎵/砷化鎵第二型量子井雷射二極 體、砷化銦/砷化銦鎵量子點、以橫截面掃描式穿隧 顯微鏡(XSTM)研究砷化銦量子點成長機制以及量 子點雷射等研究。在第二型量子井的部分我們達到 波長1300nm、半寬80meV的室溫光激螢光譜。單量 子井雷射的室溫振盪波長達1290nm，起振電流密度 達300A/cm2。在XSTM的部分，我們在InAs量子點 上以三種方法(SMD 、SMEE 及MBE) 成長 In0.33Ga0.67As覆蓋層，並以統計方法分析此三種量子 點橫截面應力分佈，我們推論出以SMD方法成長覆 蓋層的量子點擁有較長波的激發光譜，是因為其量 子點有較弱的量子侷限作用。相反的，以SMEE方 法成長覆蓋層的量子點擁有較短波的激發光譜，乃 在於其量子點有較強量子侷限作用以及量子點內 部銦的含量較少。我們提出合理的可能成長機制， 並對成長長波長量子點樣品提供改進的方向。在元 件方面，我們成功地製作出室溫發光波長在1295 nm的砷化銦/砷化銦鎵量子點雷射。所測得最高的 鬆弛震盪頻率為1.8 GHz，對應的調變頻寬達2.8 GHz。The studies of this project include the molecular beam epitaxial (MBE) growth of GaAsSb type-II quantum well (QW) and InAs/InGaAs quantum dot (QD), cross-section scanning tunneling microscopy (XSTM) technique for QD, and the related long wavelength laser diodes. In the first portion, GaAsSb/GaAs type-II QW and its laser device were grown. The PL emission wavelength of the QW successfully reaches 1300m with a FWHM of 80 meV. On the results of the type II GaAsSb/GaAs single quantum well laser diode on GaAs substrate, a low threshold current density of 300A/cm2 and an emission wavelength of 1290nm are demonstrated at room temperature. In the second portion, we use XSTM to examine strain relaxation profile of the ensembles of InAs QDs with overgrown In0.33Ga0.67As layers prepared by three distinct methods, i.e. SMD, SMEE, and MBE. A statistical analysis of strain relaxation profile allows us to infer that longest wavelength of SMD sample is due to weaker confinement, and the shortest wavelength of SMEE sample is due to both larger confinement and lower In ratio in QDs. We rationalize plausible growth mechanisms and suggest routes for further improvement. Finally, InAs/InGaAs quantum-dot lasers with emission wavelength at 1295 nm at room temperature are fabricated. The highest relaxation oscillation frequency measured at room temperature is 1.8 GHz, corresponding to a modulation bandwidth of 2.8 GHz.application/pdf427591 bytesapplication/pdfzh-TW國立臺灣大學電子工程學研究所分子束磊晶含銻化合物半導體銻砷化 鎵量子井砷化銦量子點橫截面掃描式穿隧 顯微鏡量子點雷射鬆弛震盪molecular beam epitaxySb-based compound semiconductorGaAsSb quantum wellInAs quantum dotcross-section STM. quantum-dot laserrelaxation oscillationreporthttp://ntur.lib.ntu.edu.tw/bitstream/246246/19978/1/912120E002003.pdf