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Daoudi K, Columbus S, Falcão BP, Pereira RN, Peripolli SB, Ramachandran K, Hadj Kacem H, Allagui A, Gaidi M. Label-free DNA detection using silver nanoprism decorated silicon nanoparticles: Effect of silicon nanoparticle size and doping levels. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 290:122262. [PMID: 36577246 DOI: 10.1016/j.saa.2022.122262] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 11/26/2022] [Accepted: 12/16/2022] [Indexed: 06/17/2023]
Abstract
In the present work, we have fabricated silver nanoprism (AgNPrs)/silicon nanoparticle (SiNPs) hybrid arrays for highly sensitive detection of biomolecules via surface-enhanced Raman spectroscopy (SERS) technique. SiNPs having 7 to 37 nm in size and with phosphorous doping varying from 1 × 1019 to 1 × 1020 cm-3 were synthesized in nonthermal plasma synthesis. SiNPs were further immobilized on glass substrates using spin-coating, followed by deposition of AgNPrs using the drop-casting method. SERS studies showed that AgNPrs/SiNPs hybrid arrays exhibit substantial amplification of fingerprint bands of rhodamine 6G (R6G) compared to bare silicon as the reference. Raman signal intensity was found to be dependent on the size of SiNPs, with the largest nanoparticles exhibiting the highest SERS enhancement. In addition, an increase in phosphorous doping concentration was found to reduce R6G peak intensities. AgNPrs/SiNPs hybrid arrays showed excellent stability over time and high spot-to-spot reproducibility as well. Moreover, hybrid arrays enabled DNA detection through intense vibrational modes of human genomic DNA, with a lower detection limit of 1.5 pg/µL; indicating that AgNPrs/SiNPs sensors can serve as a reliable and cost-effective biosensing platform for rapid and label-free analysis of biomolecules.
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Affiliation(s)
- Kais Daoudi
- Centre for Advanced Materials Research, Research Institute of Sciences and Engineering, University of Sharjah, PO Box 27272, Sharjah, United Arab Emirates; Department of Applied Physics and Astronomy, College of Sciences, University of Sharjah, PO Box 27272, Sharjah, United Arab Emirates.
| | - Soumya Columbus
- Centre for Advanced Materials Research, Research Institute of Sciences and Engineering, University of Sharjah, PO Box 27272, Sharjah, United Arab Emirates
| | - Bruno P Falcão
- CICECO, Department of Physics, University of Aveiro, 3810-193 Aveiro, Portugal; Department of Physics and I3N, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Rui N Pereira
- Department of Physics and I3N, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Suzana B Peripolli
- CICECO, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Krithikadevi Ramachandran
- Centre for Advanced Materials Research, Research Institute of Sciences and Engineering, University of Sharjah, PO Box 27272, Sharjah, United Arab Emirates
| | - Hassen Hadj Kacem
- Department of Applied Biology, College of Sciences, University of Sharjah, PO Box 27272, Sharjah, United Arab Emirates
| | - Anis Allagui
- Centre for Advanced Materials Research, Research Institute of Sciences and Engineering, University of Sharjah, PO Box 27272, Sharjah, United Arab Emirates; Department of Sustainable and Renewable Energy Engineering, College of Engineering, University of Sharjah, PO Box 27272, Sharjah, United Arab Emirates
| | - Mounir Gaidi
- Centre for Advanced Materials Research, Research Institute of Sciences and Engineering, University of Sharjah, PO Box 27272, Sharjah, United Arab Emirates; Department of Applied Physics and Astronomy, College of Sciences, University of Sharjah, PO Box 27272, Sharjah, United Arab Emirates; Laboratoire de Photovoltaïque, Centre de Recherches et des Technologies de l'Energie, Technopole de Borj-Cédria, Hammam-Lif 2050, Tunisia
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König D, Frentzen M, Wilck N, Berghoff B, Píš I, Nappini S, Bondino F, Müller M, Gonzalez S, Di Santo G, Petaccia L, Mayer J, Smith S, Knoch J. Turning Low-Nanoscale Intrinsic Silicon Highly Electron-Conductive by SiO 2 Coating. ACS APPLIED MATERIALS & INTERFACES 2021; 13:20479-20488. [PMID: 33878265 DOI: 10.1021/acsami.0c22360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Impurity doping in silicon (Si) ultra-large-scale integration is one of the key challenges which prevent further device miniaturization. Using ultraviolet photoelectron spectroscopy and X-ray absorption spectroscopy in the total fluorescence yield mode, we show that the lowest unoccupied and highest occupied electronic states of ≤3 nm thick SiO2-coated Si nanowells shift by up to 0.2 eV below the conduction band and ca. 0.7 eV below the valence band edge of bulk silicon, respectively. This nanoscale electronic structure shift induced by anions at surfaces (NESSIAS) provides the means for low-nanoscale intrinsic Si (i-Si) to be flooded by electrons from an external (bigger, metallic) reservoir, thereby getting highly electron- (n-) conductive. While our findings deviate from the behavior commonly believed to govern the properties of silicon nanowells, they are further confirmed by the fundamental energy gap as per nanowell thickness when compared against published experimental data. Supporting our findings further with hybrid density functional theory calculations, we show that other group IV semiconductors (diamond, Ge) do respond to the NESSIAS effect in accord with Si. We predict adequate nanowire cross-sections (X-sections) from experimental nanowell data with a recently established crystallographic analysis, paving the way to undoped ultrasmall silicon electronic devices with significantly reduced gate lengths, using complementary metal-oxide-semiconductor-compatible materials.
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Affiliation(s)
- Dirk König
- Integrated Materials Design Laboratory (IMDL), The Australian National University, Canberra, Australian Capital Territory 2601, Australia
- Smart Materials and Surface Group, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Michael Frentzen
- Institute of Semiconductor Electronics (IHT), RWTH Aachen University, Aachen 52074, Germany
| | - Noël Wilck
- Institute of Semiconductor Electronics (IHT), RWTH Aachen University, Aachen 52074, Germany
| | - Birger Berghoff
- Institute of Semiconductor Electronics (IHT), RWTH Aachen University, Aachen 52074, Germany
| | - Igor Píš
- Laboratorio TASC, IOM-CNR, Area Science Park S.S. 14 km 163.5, Trieste 34149, Italy
| | - Silvia Nappini
- Laboratorio TASC, IOM-CNR, Area Science Park S.S. 14 km 163.5, Trieste 34149, Italy
| | - Federica Bondino
- Laboratorio TASC, IOM-CNR, Area Science Park S.S. 14 km 163.5, Trieste 34149, Italy
| | - Merlin Müller
- Central Facility for Electron Microscopy, RWTH Aachen University, Aachen 52074, Germany
- Ametek GmbH, BU Gatan, Ingolstädter Straße 12, Munich 80807, Germany
| | - Sara Gonzalez
- Elettra Sincrotrone Trieste, Strada Statale 14 km 163.5, Trieste 34149, Italy
| | - Giovanni Di Santo
- Elettra Sincrotrone Trieste, Strada Statale 14 km 163.5, Trieste 34149, Italy
| | - Luca Petaccia
- Elettra Sincrotrone Trieste, Strada Statale 14 km 163.5, Trieste 34149, Italy
| | - Joachim Mayer
- Central Facility for Electron Microscopy, RWTH Aachen University, Aachen 52074, Germany
| | - Sean Smith
- Integrated Materials Design Laboratory (IMDL), The Australian National University, Canberra, Australian Capital Territory 2601, Australia
- Department of Applied Mathematics, Research School of Physics and Engineering, The Australian National University, Canberra, Australian Capital Territory 2601, Australia
| | - Joachim Knoch
- Institute of Semiconductor Electronics (IHT), RWTH Aachen University, Aachen 52074, Germany
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3
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König D, Hiller D, Wilck N, Berghoff B, Müller M, Thakur S, Di Santo G, Petaccia L, Mayer J, Smith S, Knoch J. Intrinsic ultrasmall nanoscale silicon turns n-/p-type with SiO 2/Si 3N 4-coating. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2018; 9:2255-2264. [PMID: 30202694 PMCID: PMC6122087 DOI: 10.3762/bjnano.9.210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Accepted: 07/30/2018] [Indexed: 06/08/2023]
Abstract
Impurity doping of ultrasmall nanoscale (usn) silicon (Si) currently used in ultralarge scale integration (ULSI) faces serious miniaturization challenges below the 14 nm technology node such as dopant out-diffusion and inactivation by clustering in Si-based field-effect transistors (FETs). Moreover, self-purification and massively increased ionization energy cause doping to fail for Si nano-crystals (NCs) showing quantum confinement. To introduce electron- (n-) or hole- (p-) type conductivity, usn-Si may not require doping, but an energy shift of electronic states with respect to the vacuum energy between different regions of usn-Si. We show in theory and experiment that usn-Si can experience a considerable energy offset of electronic states by embedding it in silicon dioxide (SiO2) or silicon nitride (Si3N4), whereby a few monolayers (MLs) of SiO2 or Si3N4 are enough to achieve these offsets. Our findings present an alternative to conventional impurity doping for ULSI, provide new opportunities for ultralow power electronics and open a whole new vista on the introduction of p- and n-type conductivity into usn-Si.
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Affiliation(s)
- Dirk König
- Integrated Materials Design Centre, University of New South Wales, NSW 2052, Australia
- Laboratory of Nanotechnology, Dept. of Microsystems Engineering (IMTEK), University of Freiburg, 79110, Germany
| | - Daniel Hiller
- Laboratory of Nanotechnology, Dept. of Microsystems Engineering (IMTEK), University of Freiburg, 79110, Germany
- Research School of Engineering, The Australian National University, ACT 2601, Australia
| | - Noël Wilck
- Institute of Semiconductor Electronics (IHT), RWTH Aachen University, 52074, Germany
| | - Birger Berghoff
- Institute of Semiconductor Electronics (IHT), RWTH Aachen University, 52074, Germany
| | - Merlin Müller
- Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons, RWTH Aachen University, 52074, Germany
| | - Sangeeta Thakur
- Elettra Sincrotrone Trieste, Strada Statale 14 km 163.5, 34149 Trieste, Italy
| | - Giovanni Di Santo
- Elettra Sincrotrone Trieste, Strada Statale 14 km 163.5, 34149 Trieste, Italy
| | - Luca Petaccia
- Elettra Sincrotrone Trieste, Strada Statale 14 km 163.5, 34149 Trieste, Italy
| | - Joachim Mayer
- Ernst-Ruska Centre for Microscopy and Spectroscopy with Electrons, RWTH Aachen University, 52074, Germany
| | - Sean Smith
- Integrated Materials Design Centre, University of New South Wales, NSW 2052, Australia
- National Compute Infrastructure (NCI), The Australian National University, ACT 2601, Australia
| | - Joachim Knoch
- Institute of Semiconductor Electronics (IHT), RWTH Aachen University, 52074, Germany
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Aigner W, Bienek O, Falcão BP, Ahmed SU, Wiggers H, Stutzmann M, Pereira RN. Intra- and inter-nanocrystal charge transport in nanocrystal films. NANOSCALE 2018; 10:8042-8057. [PMID: 29670986 DOI: 10.1039/c8nr00250a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The exploitation of semiconductor nanocrystal (NC) films in novel electronic and optoelectronic applications requires a better understanding of charge transport in these systems. Here, we develop a model of charge transport in NC films, based on a generalization of the concept of transport energy level ET to nanocrystal assemblies, which considers both intra- and inter-NC charge transfer processes. We conclude that the role played by each of these processes can be probed from temperature-dependent measurements of charge carrier density n and mobility μ in the same films. The model also enables the determination of the position of the Fermi energy level EF with respect to ET, an important parameter of charge transport in semiconductor materials, from the temperature dependence of n. Moreover, we provide support to an essentially temperature-independent intra-NC charge carrier mobility, considered in the transport level concept, and consequently the frequently observed temperature dependence of the overall mobility μ in NC films results from a temperature variation of the inter-NC charge transport processes. Importantly, we also conclude that the temperature dependence of conductivity in NC films should result in general from a combination of temperature variations of both n and μ. By applying the model to solution-processed Si NC films, we conclude that transport within each NC is similar to that in amorphous Si (a-Si), with charges hopping along band tail states located below the conduction band edge. For Si NCs, we obtain values of ET - EF of ∼0.25 eV. The overall mobility μ in Si NC films is significantly further reduced with respect to that typically found in a-Si due to the additional transport constraints imposed by inter-NC transfer processes inherent to a nanoparticulate film. Our model accounting for inter- and intra-NC charge transport processes provides a simple and more general description of charge transport that can be broadly applied to films of semiconductor NCs.
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Affiliation(s)
- Willi Aigner
- Walter Schottky Institut and Physik-Department, Technische Universität München, Am Coulombwall 4, 85748 Garching, Germany
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5
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Hiller D, López-Vidrier J, Gutsch S, Zacharias M, Nomoto K, König D. Defect-Induced Luminescence Quenching vs. Charge Carrier Generation of Phosphorus Incorporated in Silicon Nanocrystals as Function of Size. Sci Rep 2017; 7:863. [PMID: 28408757 PMCID: PMC5429832 DOI: 10.1038/s41598-017-01001-1] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Accepted: 03/20/2017] [Indexed: 11/23/2022] Open
Abstract
Phosphorus doping of silicon nanostructures is a non-trivial task due to problems with confinement, self-purification and statistics of small numbers. Although P-atoms incorporated in Si nanostructures influence their optical and electrical properties, the existence of free majority carriers, as required to control electronic properties, is controversial. Here, we correlate structural, optical and electrical results of size-controlled, P-incorporating Si nanocrystals with simulation data to address the role of interstitial and substitutional P-atoms. Whereas atom probe tomography proves that P-incorporation scales with nanocrystal size, luminescence spectra indicate that even nanocrystals with several P-atoms still emit light. Current-voltage measurements demonstrate that majority carriers must be generated by field emission to overcome the P-ionization energies of 110–260 meV. In absence of electrical fields at room temperature, no significant free carrier densities are present, which disproves the concept of luminescence quenching via Auger recombination. Instead, we propose non-radiative recombination via interstitial-P induced states as quenching mechanism. Since only substitutional-P provides occupied states near the Si conduction band, we use the electrically measured carrier density to derive formation energies of ~400 meV for P-atoms on Si nanocrystal lattice sites. Based on these results we conclude that ultrasmall Si nanovolumes cannot be efficiently P-doped.
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Affiliation(s)
- Daniel Hiller
- Laboratory for Nanotechnology, Dept. of Microsystems Engineering (IMTEK), University of Freiburg, Freiburg, Germany.
| | - Julian López-Vidrier
- Laboratory for Nanotechnology, Dept. of Microsystems Engineering (IMTEK), University of Freiburg, Freiburg, Germany
| | - Sebastian Gutsch
- Laboratory for Nanotechnology, Dept. of Microsystems Engineering (IMTEK), University of Freiburg, Freiburg, Germany
| | - Margit Zacharias
- Laboratory for Nanotechnology, Dept. of Microsystems Engineering (IMTEK), University of Freiburg, Freiburg, Germany
| | - Keita Nomoto
- School of Photovoltaic and Renewable Energy Engineering (SPREE), University of New South Wales (UNSW), Sydney, Australia.,Australian Centre for Microscopy and Microanalysis, The University of Sydney, Sydney, Australia
| | - Dirk König
- Integrated Materials Design Centre (IMDC), University of New South Wales (UNSW), Sydney, Australia
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6
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Kortshagen UR, Sankaran RM, Pereira RN, Girshick SL, Wu JJ, Aydil ES. Nonthermal Plasma Synthesis of Nanocrystals: Fundamental Principles, Materials, and Applications. Chem Rev 2016; 116:11061-127. [DOI: 10.1021/acs.chemrev.6b00039] [Citation(s) in RCA: 248] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Uwe R. Kortshagen
- Department
of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - R. Mohan Sankaran
- Department
of Chemical Engineering, Case Western Reserve University, Cleveland, Ohio 44106, United States
| | - Rui N. Pereira
- Department
of Physics and I3N, University of Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
- Walter
Schottky Institut and Physik-Department, Technische Universität München, Am Coulombwall 4, 85748 Garching, Germany
| | - Steven L. Girshick
- Department
of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Jeslin J. Wu
- Department
of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Eray S. Aydil
- Department
of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States
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7
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Lu P, Mu W, Xu J, Zhang X, Zhang W, Li W, Xu L, Chen K. Phosphorus Doping in Si Nanocrystals/SiO2 multilayers and Light Emission with Wavelength compatible for Optical Telecommunication. Sci Rep 2016; 6:22888. [PMID: 26956425 PMCID: PMC4783703 DOI: 10.1038/srep22888] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Accepted: 02/23/2016] [Indexed: 11/30/2022] Open
Abstract
Doping in semiconductors is a fundamental issue for developing high performance devices. However, the doping behavior in Si nanocrystals (Si NCs) has not been fully understood so far. In the present work, P-doped Si NCs/SiO2 multilayers are fabricated. As revealed by XPS and ESR measurements, P dopants will preferentially passivate the surface states of Si NCs. Meanwhile, low temperature ESR spectra indicate that some P dopants are incorporated into Si NCs substitutionally and the incorporated P impurities increase with the P doping concentration or annealing temperature increasing. Furthermore, a kind of defect states will be generated with high doping concentration or annealing temperature due to the damage of Si crystalline lattice. More interestingly, the incorporated P dopants can generate deep levels in the ultra-small sized (~2 nm) Si NCs, which will cause a new subband light emission with the wavelength compatible with the requirement of the optical telecommunication. The studies of P-doped Si NCs/SiO2 multilayers suggest that P doping plays an important role in the electronic structures and optoelectronic characteristics of Si NCs.
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Affiliation(s)
- Peng Lu
- School of Electronic Science and Engineering, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Weiwei Mu
- School of Electronic Science and Engineering, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Jun Xu
- School of Electronic Science and Engineering, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Xiaowei Zhang
- School of Electronic Science and Engineering, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Wenping Zhang
- School of Electronic Science and Engineering, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Wei Li
- School of Electronic Science and Engineering, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Ling Xu
- School of Electronic Science and Engineering, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
| | - Kunji Chen
- School of Electronic Science and Engineering, National Laboratory of Solid State Microstructures, Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, 210093, China
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Oliva-Chatelain BL, Ticich TM, Barron AR. Doping silicon nanocrystals and quantum dots. NANOSCALE 2016; 8:1733-1745. [PMID: 26727507 DOI: 10.1039/c5nr04978d] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The ability to incorporate a dopant element into silicon nanocrystals (NC) and quantum dots (QD) is one of the key technical challenges for the use of these materials in a number of optoelectronic applications. Unlike doping of traditional bulk semiconductor materials, the location of the doping element can be either within the crystal lattice (c-doping), on the surface (s-doping) or within the surrounding matrix (m-doping). A review of the various synthetic strategies for doping silicon NCs and QDs is presented, concentrating on the efficacy of the synthetic routes, both in situ and post synthesis, with regard to the structural location of the dopant and the doping level. Methods that have been applied to the characterization of doped NCs and QDs are summarized with regard to the information that is obtained, in particular to provide researchers with a guide to the suitable techniques for determining dopant concentration and location, as well as electronic and photonic effectiveness of the dopant.
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Affiliation(s)
| | - Thomas M Ticich
- Department of Chemistry, Centenary College of Louisiana, Shreveport, LA 71134, USA
| | - Andrew R Barron
- Department of Chemistry, Rice University, Houston, TX 77005, USA and Department of Materials Science and Nanoengineering, Rice University, Houston, TX 77005, USA
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König D, Gutsch S, Gnaser H, Wahl M, Kopnarski M, Göttlicher J, Steininger R, Zacharias M, Hiller D. Location and Electronic Nature of Phosphorus in the Si Nanocrystal--SiO2 System. Sci Rep 2015; 5:9702. [PMID: 25997696 PMCID: PMC4650604 DOI: 10.1038/srep09702] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Accepted: 03/04/2015] [Indexed: 11/13/2022] Open
Abstract
Up to now, no consensus exists about the electronic nature of phosphorus (P) as donor for SiO2-embedded silicon nanocrystals (SiNCs). Here, we report on hybrid density functional theory (h-DFT) calculations of P in the SiNC/SiO2 system matching our experimental findings. Relevant P configurations within SiNCs, at SiNC surfaces, within the sub-oxide interface shell and in the SiO2 matrix were evaluated. Atom probe tomography (APT) and its statistical evaluation provide detailed spatial P distributions. For the first time, we obtain ionisation states of P atoms in the SiNC/SiO2 system at room temperature using X-ray absorption near edge structure (XANES) spectroscopy, eliminating structural artefacts due to sputtering as occurring in XPS. K energies of P in SiO2 and SiNC/SiO2 superlattices (SLs) were calibrated with non-degenerate P-doped Si wafers. results confirm measured core level energies, connecting and explaining XANES spectra with h-DFT electronic structures. While P can diffuse into SiNCs and predominantly resides on interstitial sites, its ionization probability is extremely low, rendering P unsuitable for introducing electrons into SiNCs embedded in SiO2. Increased sample conductivity and photoluminescence (PL) quenching previously assigned to ionized P donors originate from deep defect levels due to P.
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Affiliation(s)
- Dirk König
- 1] Integrated Material Design Centre (IMDC), UNSW, Sydney, Australia [2] School of Photovoltaic and Renewable Energy Engineering (SPREE), UNSW, Sydney, Australia
| | - Sebastian Gutsch
- Laboratory of Nanotechnology, Dept. of Microsystems Engineering (IMTEK), University of Freiburg, Germany
| | - Hubert Gnaser
- Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Germany
| | - Michael Wahl
- Department of Physics and Research Center OPTIMAS, University of Kaiserslautern, Germany
| | - Michael Kopnarski
- Institute for Surface and Thin Film Analysis (IFOS) Ltd., Kaiserslautern, Germany
| | - Jörg Göttlicher
- ANKA Synchrotron Radiation Facility, Karlsruhe Institute of Technology, Germany
| | - Ralph Steininger
- ANKA Synchrotron Radiation Facility, Karlsruhe Institute of Technology, Germany
| | - Margit Zacharias
- Laboratory of Nanotechnology, Dept. of Microsystems Engineering (IMTEK), University of Freiburg, Germany
| | - Daniel Hiller
- Laboratory of Nanotechnology, Dept. of Microsystems Engineering (IMTEK), University of Freiburg, Germany
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