Growth and characterization of InAs columnar quantum dots on GaAs substrate
Growth and characterization of InAs columnar quantum dots on GaAs substrate
复制标题
GaAs 衬底上 InAs 柱状量子点的生长及表征
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
A. Fiore
中科院分区：
文献类型：
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作者：
Lianhe H. Li;G. Patriarche;M. Rossetti;A. Fiore
研究了用分子束外延技术在砷化镓衬底上生长InAs柱状量子点。CQD是通过沉积1.8单分子层(ML)InAs种子点层和短周期的GaAs/InAs超晶格(SL)形成的。研究发现，CQD的生长对生长中断(GI)和生长温度非常敏感。较长的GI和较高的生长温度都会影响CQD的尺寸色散，从而导致光致发光(PL)光谱的展宽和额外的光致发光峰尾的存在。通过适当选择GI和生长温度，生长出了周期数可达35的无塑性松弛的量子点，包括GaAs3ML/InAs(0.62ML)SL。相应的等效厚度为41 nm，比In组分平均为16%的应变InGaAs层的理论临界厚度高两倍。临界厚度的增加部分与CQD的形成有关。以五为基数...
The growth of InAs columnar quantum dots (CQDs) on GaAs substrates by molecular beam epitaxy was investigated. The CQDs were formed by depositing a 1.8 monolayer (ML) InAs seed dot layer and a short period GaAs/InAs superlattice (SL). It was found that the growth of the CQDs is very sensitive to growth interruption (GI) and growth temperature. Both longer GI and higher growth temperature impact the size dispersion of the CQDs, which causes the broadening of photoluminescence (PL) spectrum and the presence of the additional PL peak tails. By properly choosing the GI and the growth temperature, CQDs including GaAs (3 ML)/InAs (0.62 ML) SL with period number up to 35 without plastic relaxation were grown. The corresponding equivalent thickness of the SL is 41 nm which is two times higher than the theoretical critical thickness of the strained InGaAs layer with the same average In composition of 16%. The increase of the critical thickness is partially associated with the formation of the CQDs. Based on a five...