摘要
采用金属有机物化学气相沉积法生长了两种不同结构参数GaAs/AlxGa1-xAs量子阱材料。利用傅里叶光谱仪分别对势垒中Al组分为0.20,0.30的1#,2#样品进行77K液氮温度下光谱响应测试。结果显示:1#,2#峰值响应波长为8.38,7.59μm,而根据薛定谔方程得到峰值波长为9.694,8.134μm,二者误差分别为13.6%,6.68%。针对误差过大及吸收峰向高能方向发生漂移的现象,利用高分辨透射扫描电镜对样品微观界面结构进行分析,结果显示,样品存在不同程度的位错及不均匀性。结果表明:位错引起AlGaAs与GaAs晶格不匹配,是造成1#误差较大的主要原因;峰值响应波长随势垒中Al组分的降低而增大,说明Al组分减小致使量子阱子带间距离缩小是导致峰值响应波长红移的原因。
Two GaAs/AlxGa1-xAs infrared quantum well materials with different structure parameters have been made by using metal organic chemical vapor deposition. The photoresponse spectra are obtained at 77 K by use of Fourier transform spectrometer for two sample-devices of GaAs/AlxGa1-xAs quantum well infrared photodetectors with an Al content of 0.20 and 0.30 respectively. The results show the peak wavelengths of 1# and 2# are 8.38 μm and 7.59 μm, while they are 9.694 μm and 8.134 μm according to the Schr？dinger equation, and the errors between them are 13.6%, 6.68%, respectively. The crystal structure is investigated by using high-resolution scanning transmission electron microscope to analyse the main reason of the large errors and peak wavelength redshift, which shows that there is thread dislocation and nonuniformity in different degrees. The main reason causing 1# error much larger is the crystal lattice mismatch between AlGaAs and GaAs. The fact that the peak wavelength increases with Al content reducing shows reducing Al content will lead to narrowing of the spacing between subbands and peak wavelength redshift.
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2013年第6期1405-1408,共4页
High Power Laser and Particle Beams
基金
国家自然科学基金项目(50975288)
国家总装备部共性技术支撑项目(4040503104)
陕西教育厅项目(12Jk0980)
西安市创新计划项目(CXY1007-3)
关键词
量子阱红外探测器
高分辨透射扫描电镜
金属有机物化学气相沉积
AL组分
峰值响应波长
quantum well infrared photodetectors, high-resolution scanning transmission electron microscope, metal organic chemical vapor deposition, Al content, peak response wavelength
