Abstract
The structure of nanocrystal-matrix interface and strain in embedded nanocrystals are studied using large-scale atomistic simulations, with the examples of Si nanocrystal embedded in amorphous matrix of SiO2. Photoluminescence from silicon nanocrystals embedded in a dielectric matrix like SiO2 and Si3N4 are promising for Si-based optical devices. The nanocrystal-matrix interface plays a crucial role in understanding its optical and electrical properties. Nanocrystals with diameters varying from 2.17 to 4.56 nm are studied. A detailed quantitative analysis of the variation of Si/SiO2 interface structure and strain distribution with nanocrystal diameter is reported. A linear variation of the interface width with nanocrystal diameter is observed with thinner interfaces for larger nanocrystals. Local deformation analysis reveals that the smaller nanocrystals are highly strained, whereas the strain in the larger ones shifts to the interface. This is in accordance with observed increase in total percentage of defect states in the interface from 39 to 70% for diameter increasing from 2.17 to 4.56 nm. Moreover, based on the atomic arrangements at the interface, optically active defects like Pb centres, E centres and non-bridging oxygen centres are identified and a dominance of Pb centres is observed for all the nanocrystals. The detailed structural characterization-related investigations using the proposed simulation approach will find useful application in designing system-level response of embedded nanocrystals and also to correlate various experimental observations.
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Banerjee S (2003) Statistical emission of electrons from nanocrystalline silicon quantum dot memory nodes in a few-electron MOSFET memory device. Solid State Commun 125(10):567–570. https://doi.org/10.1016/S0038-1098(03)00006-1
Bardeen J, Shockley W (1950) Deformation potentials and mobilities in non-polar crystals. Phys Rev 80:72–80
Bonafos C, Carrada M, Benassayag G, Schamm-Chardon S, Groenen J, Paillard V, Pecassou B, Claverie A, Dimitrakis P, Kapetanakis E, Ioannou-Sougleridis V, Normand P, Sahu B, Slaoui A (2012) Si and Ge nanocrystals for future memory devices. Materials Science in Semiconductor Processing (0). https://doi.org/10.1016/j.mssp.2012.09.004
Brongersma ML, Polman A, Min KS, Boer E, Tambo T, Atwater HA (1998) Tuning the emission wavelength of Si nanocrystals in SiO2 by oxidation. Appl Phys Lett 72(20):2577. https://doi.org/10.1063/1.121423
Castro C, Schamm-Chardon S, Pecassou B, Andreozzi A, Seguini G, Perego M, BenAssayag G (2013) In-plane organization of silicon nanocrystals embedded in SiO2 thin films. Nanotechnology 24:075,302–075,307. https://doi.org/10.1088/0957-4484/24/7/075302
Choi BH, Hwang SW, Kim IG, Shin HC, Kim Y, Kim EK (1998) Fabrication and room-temperature characterization of a silicon self-assembled quantum-dot transistor. Appl Phys Lett 73 (21):3129–3131. https://doi.org/10.1063/1.122695
Comedi D, Zalloum O, Wojcik J, Mascher P (2006) Light emission from hydrogenated and unhydrogenated Si-nanocrystal/Si dioxide composites based on PECVD-grown Si-rich Si oxide films. IEEE J Sel Top Quantum Electron 12 (6):1561–1569. https://doi.org/10.1109/JSTQE.2006.885388
Cruz-Chu ER, Aksimentiev A, Schulten K (2006) Water-silica force field for simulating nanodevices. J Phys Chem B 110(43):21,497–21,508. https://doi.org/10.1021/jp063896o
Djurabekova F, Nordlund K (2008) Atomistic simulation of the interface structure of Si nanocrystals embedded in amorphous silica. Phys Rev B 77:115,325. https://doi.org/10.1103/PhysRevB.77.115325
Erogbogbo F, Yong KT, Roy I, Xu G, Prasad PN, Swihart MT (2008) Biocompatible luminescent silicon quantum dots for imaging of cancer cells. ACS Nano 2(5):873–878. https://doi.org/10.1021/nn700319z
Grunthaner F, Grunthaner P (1986) Chemical and electronic structure of the SiO2/Si interface. Mater Sci Rep 1(2):65–160. https://doi.org/10.1016/S0920-2307(86)80001-9
Guerra R, Degoli E, Ossicini S (2009) Size, oxidation, and strain in small Si/SiO2 nanocrystals. Phys Rev B 80(15):155,332. https://doi.org/10.1103/PhysRevB.80.155332
Hadjisavvas G, Kelires P (2007) Theory of interface structure, energetics, and electronic properties of embedded Si/a-SiO2 nanocrystals. Physica E: Low-dimensional Systems and Nanostructures 38(1–2):99–105. https://doi.org/10.1016/j.physe.2006.12.009
Hadjisavvas G, Kelires PC (2004) Structure and energetics of Si nanocrystals embedded in a-SiO2. Phys Rev Lett 93 (22):226,104. https://doi.org/10.1103/PhysRevLett.93.226104
Herman F, Kasowski RV (1981) Electronic structure of defects at Si/SiO2 interfaces. J Vac Sci Technol 19(3):395–401. https://doi.org/10.1116/1.571071
Hoover WG (1985) Canonical dynamics: equilibrium phase-space distributions. Phys Rev A 31 (3):1695–1697. https://doi.org/10.1103/PhysRevA.31.1695
Ippolito M, Meloni S, Colombo L (2008) Interface structure and defects of silicon nanocrystals embedded into a-SiO2. Appl Phys Lett 93 (15):153,109–153,109–3. https://doi.org/10.1063/1.2999629
Ishimaru M (2002) Atomistic simulations of structural relaxation processes in amorphous silicon. J Appl Phys 91(2):686–689. https://doi.org/10.1063/1.1425437
Ishimaru M, Munetoh S, Motooka T (1997) Generation of amorphous silicon structures by rapid quenching: a molecular-dynamics study. Phys Rev B 56:15,133–15,138. https://doi.org/10.1103/PhysRevB.56.15133
Jivanescu M, Hiller D, Zacharias M, Stesmans A (2011) Size dependence of Pb-type photoluminescence quenching defects at the Si nanocrystal interface. Europhys Lett 96 (2):27,003. https://doi.org/10.1209/0295-5075/96/27003
Kahler U, Hofmeister H (2000) Synthesis of Si nanoparticles within buried layers of SiOx. J Metastable Nanocryst Mater 8:488–493. https://doi.org/10.4028/www.scientific.net/JMNM.8.488
Kanemitsu Y, Ogawa T, Shiraishi K, Takeda K (1993) Visible photoluminescence from oxidized Si nanometer-sized spheres: exciton confinement on a spherical shell. Phys Rev B 48(7):4883–4886. https://doi.org/10.1103/PhysRevB.48.4883
Kanemitsu Y, Fukunishi Y, Iiboshi M, Okamoto S, Kushida T (2000) Visible luminescence from Si/SiO2 quantum wells and dots: confinement and localization of excitons. Physica E: Low-dimensional Systems and Nanostructures 7:456–460. https://doi.org/10.1016/S1386-9477(99)00357-4
Khriachtcheva L, Räsänen M (2006) Laser-controlled stress of Si nanocrystals in a free-standing Si/ SiO2 superlattice. Appl Phys Lett 88:013,102. https://doi.org/10.1063/1.2161399
Kim S, Kim MC, Choi SH, Kim KJ, Hwang HN, Hwang CC (2007) Size dependence of Si 2p core-level shift at Si nanocrystal/SiO2 interfaces. Appl Phys Lett 91(10):103,113. https://doi.org/10.1063/1.2776014
Kohno H, Iwasaki T, Mita Y, Takeda S (2002) One-phonon Raman scattering studies of chains of crystalline-Si nanospheres. J Appl Phys 91(5):3232– 3235
Kosowsky SD, Pershan PS, Krisch KS, Bevk J, Green ML, Brasen D, Feldman LC, Roy PK (1997) Evidence of annealing effects on a high-density Si/SiO2 interfacial layer. Appl Phys Lett 70(23):3119–3121. https://doi.org/10.1063/1.119090
Lampin E, Krzeminski C (2011) Regrowth of oxide-embedded amorphous silicon studied with molecular dynamics. J Appl Phys 109(12):123,509–123,509–5. https://doi.org/10.1063/1.3596815
Lenahan P, Mishima T, Jumper J, Fogarty TN, Wilkins RT (2001) Direct experimental evidence for atomic scale structural changes involved in the interface-trap transformation process. IEEE Trans Nucl Sci 48(6):2131–2135. https://doi.org/10.1109/23.983184
Lin CF, Tseng WT, Feng MS (2000) Formation and characteristics of silicon nanocrystals in plasma-enhanced chemical-vapor-deposited silicon-rich oxide. J Appl Phys 87(6):2808–2815. https://doi.org/10.1063/1.372260
Lin GR, Lin CJ, Lin CK, Chou LJ, Chueh YL (2005) Oxygen defect and Si nanocrystal dependent white-light and near-infrared electroluminescence of Si-implanted and plasma-enhanced chemical-vapor deposition-grown Si-rich SiO2. J Appl Phys 97:094,306
Melnik R, Roy Mahapatra D (2007) Coupled effects in quantum dot nanostructures with nonlinear strain and bridging modelling scales. Comput Struct 85(11–14):698–711. https://doi.org/10.1016/j.compstruc.2007.01.046, fourth {MIT} Conference on Computational Fluid and Solid Mechanics
Munetoh S, Moriguchi K, Shintani A, Nishihira K, Motooka T (2001) Molecular dynamics simulations of solid-phase epitaxy of Si: defect formation processes. Phys Rev B 64:193,314. https://doi.org/10.1103/PhysRevB.64.193314
Munetoh S, Motooka T, Moriguchi K, Shintani A (2007) Interatomic potential for SiO systems using Tersoff parameterization. Comput Mater Sci 39(2):334–339. https://doi.org/10.1016/j.commatsci.2006.06.010
Nose S (1984) A unified formulation of the constant temperature molecular dynamics methods. J Chem Phys 81(1):511–519. https://doi.org/10.1063/1.447334
Pavesi L, Negro LD, Mazzoleni C, Franzò G, Priolo F (2000) Optical gain in silicon nanocrystals. Nature 408(6811):440–444. https://doi.org/10.1038/35044012
Plimpton S (1995) Fast parallel algorithms for short-range molecular dynamics. J Comput Phys 117(1):1–19. https://doi.org/10.1006/jcph.1995.1039. http://www.sciencedirect.com/science/article/pii/S002199918571039X
Scheer KC, Rao RA, Muralidhar R, Bagchi S, Conner J, Lozano L, Perez C, Sadd M, White BE (2003) Thermal oxidation of silicon nanocrystals in O2 and NO ambient. J Appl Phys 93(9):5637–5642. https://doi.org/10.1063/1.1565172
Seino K, Bechstedt F, Kroll P (2009) Influence of SiO2 matrix on electronic and optical properties of Si nanocrystals. Nanotechnology 20:135,702
Shenoy BM, Roy Mahapatra D, Hegde G (2013) A model of coupled thermal, mechanical, and electrostatic field effects in III-N thin film heterostructures. J Appl Phys 114(4):044506. https://doi.org/10.1063/1.4816261
Skuja L (1998) Optically active oxygen-deficiency-related centers in amorphous silicon dioxide. J Non-Cryst Solids 239:16–48
Stirling A, Pasquarello A (2005) Modelling of paramagnetic trivalent silicon defect centres in amorphous silica and at Si/SiO2 interfaces. J Phys Condens Matter 17(21):S2099. https://doi.org/10.1088/0953-8984/17/21/006
Tiwari S, Rana F, Hanafi H, Hartstein A, Crabbé EF, Chan K (1996) A silicon nanocrystals based memory. Appl Phys Lett 68(10):1377–1379. https://doi.org/10.1063/1.116085
Vinciguerra V, Franzò G, Priolo F, Iacona F, Spinella C (2000) Quantum confinement and recombination dynamics in silicon nanocrystals embedded in Si/SiO2 superlattices. J Appl Phys 87(11):8165–8173. https://doi.org/10.1063/1.373513
White C, Budai J, Withrow S, Zhu J, Sonder E, Zuhr R, Meldrum A, Hembree JrD, Henderson D, Prawer S (1998) Encapsulated semiconductor nanocrystals formed in insulators by ion beam synthesis. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 141(1-4):228–240. https://doi.org/10.1016/S0168-583X(98)00091-3
Yedji M, Demarche J, Terwagne G, Delamare R, Flandre D, Barba D, Koshel D, Ross GG (2011) Method for fabricating third generation photovoltaic cells based on Si quantum dots using ion implantation into SiO2. J Appl Phys 109 (8):084,337–084,337–6. https://doi.org/10.1063/1.3575325
Yilmaz DE, Bulutay C, Çaǧin T (2009) Analysis of strain fields in silicon nanocrystals. Appl Phys Lett 94:191,914. https://doi.org/10.1063/1.3138163
Zacharias M, Bläsing J, Veit P, Tsybeskov L, Hirschman K, Fauchet PM (1999) Thermal crystallization of amorphous Si/SiO2 superlattices. Appl Phys Lett 74(18):2614–2616. https://doi.org/10.1063/1.123914
Zatryb G, Podhorodecki A, Misiewicz J, Cardin J, Gourbilleau F (2013) Correlation between matrix structural order and compressive stress exerted on silicon nanocrystals embedded in silicon-rich silicon oxide. Nanoscale Res Lett 8(1):40. https://doi.org/10.1186/1556-276X-8-40
Zimmerman JA, Bammann b DJ, Gao H (2009) Deformation gradients for continuum mechanical analysis of atomistic simulations. Int J Solids Struct 46:238–253. https://doi.org/10.1016/j.ijsolstr.2008.08.036
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The authors would like to acknowledge financial support under the CoNE project, NPMASS Program, Government of India, Grant No. PARC 3.9, and ARDB-ACECOST Program Phase III, DRDO, Grant No. 1637.
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Shenoy, B.M., Hegde, G.M. & Mahapatra, D.R. Embedded silicon nanocrystal interface structure and strain. J Nanopart Res 20, 14 (2018). https://doi.org/10.1007/s11051-017-4120-3
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DOI: https://doi.org/10.1007/s11051-017-4120-3