Autor: |
Wolny, P., Anikeeva, M., Sawicka, M., Schulz, T., Markurt, T., Albrecht, M., Siekacz, M., Skierbiszewski, C. |
Předmět: |
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Zdroj: |
Journal of Applied Physics; 2018, Vol. 124 Issue 6, pN.PAG-N.PAG, 9p, 3 Diagrams, 2 Charts, 6 Graphs |
Abstrakt: |
We investigate the In content in single monolayer (ML)-thick InxGa1-xN quantum wells (QWs) as a function of the growth temperature ranging from 650 °C to 480 °C, stacked in a superlattice (SL). The SLs were grown by plasma-assisted molecular beam epitaxy using high N-flux. For the evaluation of the indium concentrations, scanning transmission electron microscopy high angle annular dark field (STEM-HAADF) studies were combined with local lattice parameter measurements obtained from high-resolution transmission electron microscopy (HRTEM) images. The mean In content in the QWs increases from 11% to 23% when the growth temperature decreases from 650 °C to 610 °C. Further decrease in the growth temperature results in a saturation of the mean In content. Our experiments show that a substantial reduction of the growth temperature is not a practical way to obtain pseudomorphically grown InN MLs on GaN(0001). The InGaN QW thickness is limited to 1 ML and is not affected by a change of growth temperature. For two SL structures grown at constant temperatures of 640 °C and 600 °C, increase in the In content in the QWs causes a shift in the peak emission from 382 to 395 nm, as was measured by cathodoluminescence at 7 K. The application of X-ray diffraction studies to analyze the composition of InGaN ML-thick QWs in SLs is discussed. [ABSTRACT FROM AUTHOR] |
Databáze: |
Complementary Index |
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