The InAs quantum dots (QDs) grown by molecular beam epitaxy (MBE) are studied as a function of growth temperature at a specific InAs coverage of 2.7 ML. The QDs density is significantly reduced from 8.0 × 1010 to 5.0 × 109 cm-2 as the growth temperature increases from 480°C to 520°C, while the average QDs diameter and height becomes larger. The effects of the growth temperature on the evolution of bimodal QDs are investigated by combining atomic force microscopy (AFM) and photoluminescence (PL). Results show that the formation of the bimodal QDs depends on the growth temperature: at a growth temperature of 480°C, large QDs result from the small QDs coalition; at a growth temperature of 535°C, the indium desorption and InAs segregation result in the formation of small QDs.
JIA Guozhi, YAO Jianghong, SHU Yongchun, WANG Zhanguo
. Optical properties and structure of InAs quantum
dots in near-infrared band[J]. Frontiers of Optoelectronics, 2008
, 1(1-2)
: 134
-137
.
DOI: 10.1007/s12200-008-0033-1
1. Kang Y H, Park J, Lee U H, et al.. Effect of the dot size distribution on quantumdot infrared photoresponse and temperature-dependent dark current. Applied Physics Letters, 2003, 82(7): 1099–1101. doi:10.1063/1.1555711
2. Shchekin O B, Park G, Huffaker D L, et al.. Discrete energy level separation and the thresholdtemperature dependence of quantum dot lasers. Applied Physics Letters, 2000, 77(4): 466–468. doi:10.1063/1.127012
3. Mukhametzhanov I, Wei Z, Heitz R, et al.. Punctuated island growth: an approach to examinationand control of quantum dot density, size, and shape evolution. Applied Physics Letters, 1999, 75(1): 85–87. doi:10.1063/1.124284
4. Fan X W, Shan C X, Yang Y, et al.. Growth and characterestics of ZnCdSe and ZnSeSquantum dots under S-K and V-W modes. ChineseJournal of Luminescence, 2005, 26(1): 9–14 (in Chinese)
5. Liu H W, Laskar I R, Huang C P, et al.. Synthesis and applications of luminescent CdSequantum dots for OLEDs. Chinese Journalof Luminescence, 2005, 26(3): 321–326
6. Li Y F, Han P D, Chen Z, et al.. Growth and property of surface stress inducedInGaN quantum dots. Chinese Journal ofSemiconductors, 2003, 24(1): 39–43 (in Chinese)
7. Lee H, Lowe-Webb R R, Yang W, et al.. Formation of InAs/GaAs quantum dots by molecularbeam epitaxy: reversibility of the islanding transition. Applied Physics Letters, 1997, 71(16)2325–2327. doi:10.1063/1.120062
8. Schaffer W J, Lind M D, Kowalczyk S P, et al.. Nucleation and strain relaxation at the InAs/GaAs(100)heterojunction. Journal of Vacuum Scienceand Technology B, 1983, 1(3): 688–695. doi:10.1116/1.582579
9. Foxon C T, Joyce B A . Surface processes controllingthe growth of GaxIn1–xAs and GaxIn1-xP alloy films byMBE. Journal of Crystal Growth, 1978, 44(1): 75–83. doi:10.1016/0022-0248(78)90330-5
10. Leonard D, Krishnamurthy M, Fafard S, et al.. MBE Growth of quantum dots from strained coherentuniform islands of InGaAs on GaAs. Journalof Vacuum Science and Technology B, 1994, 12(2): 1063–1066. doi:10.1116/1.587088
11. El-Emawy A A, Birudavolu S, Wong P S, et al.. Formation trends in quantum dot growth usingmetalorganic chemical vapor deposition. Journal of Applied Physics, 2003, 93(6): 3529–3534. doi:10.1063/1.1543647
12. Dehaese O, Wallart X, Mollot F . Kinetic model of element III segregation during molecularbeam epitaxy of III-III8-V semiconductor compounds. Applied Physics Letters, 1995, 66(1): 52–54. doi:10.1063/1.114180
13. Jung S I, Yeo H Y, Yun I, et al.. Photoluminescence study on the growth of self-assembledInAs quantum dots: formation characteristics of bimodal-sized quantumdot. Physica E, 2006, 33(1): 280–283. doi:10.1016/j.physe.2006.03.150
14. Ribeiro E, Maltez R L, Carvalho W, et al.. Optical and structural properties of InAsP ternaryself-assembled quantum dots embedded in GaAs. Applied Physics Letters, 2002, 81(16): 2953–2955. doi:10.1063/1.1513215