Structural and Photoluminescence Properties for Highly Strain-Compensated InGaAs/InAlAs Superlattice
Structural and Photoluminescence Properties for Highly Strain-Compensated InGaAs/InAlAs Superlattice
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高应变补偿 InGaAs/InAlAs 超晶格的结构和光致发光特性
DOI：
10.1088/0256-307x/26/7/077808
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发表时间：
2009-07-01
影响因子：
3.5
通讯作者：
Li Yao-Yao
中科院分区：
文献类型：
--
作者：
Gu Yi;Zhang Yong-Gang;Li Yao-Yao
用20个周期的高应变补偿InGaAs/InAlAs超晶格研究了应变补偿效应。单层的晶格失配高达1%左右，厚度接近临界厚度。X射线衍射测量表明，虽然结构参数在结构稳定性的理论设计准则范围内，但晶格缺陷并不严重，但仍然存在。界面粗糙和成分波动是导致晶格缺陷的主要原因。光致发光测量表明，样品中存在大量的热激活非辐射复合。此外，复合过程从较低温度下的激子复合逐渐演变为较高温度下的带间复合，这在器件应用中应该得到考虑。
The effects of strain compensation are investigated by using twenty periods of highly strain-compensated InGaAs/InAlAs superlattice. The lattice mismatches of individual layers are as high as about 1%, and the thicknesses are close to critical thicknesses. X-ray diffraction measurements show that lattice imperfectness is not serious but still present, though the structural parameters are within the range of theoretical design criteria for structural stability. Rough interfaces and composition fluctuations are the primary causes for lattice imperfectness. Photoluminescence measurements show the large thermally activated nonradiative recombination in the sample. In addition, the recombination process gradually evolves from excitonic recombination at lower temperatures to band-to-band recombination at higher temperatures, which should be considered in device applications.