Dr Thomas Walther
CPhys, PhD, Dipl-Phys
School of Electrical and Electronic Engineering
Reader in Advanced Electron Microscopy
Semiconductor Materials and Devices Research Group
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+44 114 222 5891
Full contact details
School of Electrical and Electronic Engineering
- Profile
-
I received my undergraduate degree in physics from RWTH Aachen in 1993 and my PhD in materials science from the University of Cambridge in 1996/97.
I was a postdoc at CEA Grenoble, Université d’Aix-Marseille (both in France) and University of Bonn (in Germany) where I later became assistant professor in the chemistry department.
After a short spell at a new research centre where I sat up an electron microscopy lab in the same city, I joined the University of Sheffield as Senior Lecturer in 2006 and was promoted to a readership in 2010.
My research focuses on electron microscopy as a fundamental tool to measure chemical changes at the interfaces between different materials with atomic resolution. This can produce fantastic images that directly show where the atoms are located!
My research is relevant for understanding epitaxial growth processes as well as degradation and failure of semiconductor devices, such as transistors, light-emitting diodes, lasers and solar cells: atoms can sometimes move to lattice positions where they should not be, their agglomeration producing extended lattice defects called dislocations that can multiply and finally lead to device failure.
These studies bridge the gap from fundamental science to applied engineering.
My research involves aspects of electron optics, solid state physics and inorganic chemistry as it combines different experimental methods of high-resolution analytical electron microscopy, based on inelastic electron scattering and X-ray photon generation, with detailed modelling of atomic movements in solids.
Presently, this methodology is expanded into materials for energy conversion and storage, such as electrodes in batteries.
- Qualifications
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- CPhys, Fellow of the Institute of Physics, Fellow of the Royal Microscopical Society
- PhD (Materials Science & Metallurgy), University of Cambridge, 1997
- Dipl.-Phys. (Physics), RWTH Aachen, Germany, 1993
- Research interests
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- Method development for analytical transmission electron microscopy, including energy-dispersive X-ray and electron energy-loss spectroscopy
- Diffusion and segregation measurements in semiconductor nano-structures
- Lattice defects in quantum dots, nano-wires and quantum wells
- Characterization of doping, surface treatments, metal layers for plasmonics and oxides for energy storage applications
- Microstructural characterization of prototype electronic devices, such as photodiodes, field-effect transistors, quantum well, quantum dot or quantum cascade lasers, photovoltaic cells
- Engagement in electron microscopy societies and international conference organisation
- Publications
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Books
- Preface: Microscopy of Semiconducting Materials 2015. Bristol: IOP Publishing.
Edited books
- 16th International Conference on Microscopy of Semiconducting Materials. Bristol: IOP Publishing.
Journal articles
- Towards quantification of doping in gallium arsenide nanostructures by low-energy scanning electron microscopy and conductive atomic force microscopy. Journal of Microscopy, 293.
- Recent improvements in quantification of energy-dispersive X-ray spectra and maps in electron microscopy of semiconductors. Applied Research, 3(4-5).
- Clustering in gallium ion beam sputtered compound materials driven by bond strength and interstitial/vacancy reaction. Applied Physics Letters, 123(10).
- Role of Interdiffusion and segregation during the life of indium gallium arsenide quantum dots, from cradle to grave. Nanomaterials, 12(21).
- Measuring Non-Destructively the Total Indium Content and Its Lateral Distribution in Very Thin Single Layers or Quantum Dots Deposited onto Gallium Arsenide Substrates Using Energy-Dispersive X-Ray Spectroscopy in a Scanning Electron Microscope. Nanomaterials, 12(13).
- Quantitative microstructural and spectroscopic investigation of inversion domain boundaries in sintered zinc oxide ceramics doped with iron oxide. International Journal of Materials Research, 97(7), 934-942.
- Failure Analysis of Some Commercial Spotlights Based on Light Emitting Diodes. Electronics, 11(1), 48-48.
- Measurement of nanometre-scale gate oxide thicknesses by energy-dispersive X-ray spectroscopy in a scanning electron microscope combined with Monte Carlo simulations. Nanomaterials, 11(8).
- Preface for the special issue on Microscopy of Semiconducting Materials 2019. Semiconductor Science and Technology, 35(12). View this article in WRRO
- Measurement of diffusion and segregation in semiconductor quantum dots and quantum wells by transmission electron microscopy : a guide. Nanomaterials, 9(6). View this article in WRRO
- Self-consistent absorption correction for quantifying very noisy X-ray maps: group III nitride nanowires as an example. Journal of Microscopy, 272(2), 111-122. View this article in WRRO
- Materials characterisation and modelling on the small scale. Materials Science and Technology (United Kingdom), 34(13), 1529-1530. View this article in WRRO
- Stranski–Krastanov growth of (Si)Ge/Si(001): transmission electron microscopy compared with segregation theory. Materials Science and Technology. View this article in WRRO
- Comment on ‘Nanoscale mapping of optical band gaps using monochromated electron energy loss spectroscopy’. Nanotechnology, 29(31), 318001-318001. View this article in WRRO
- Transmission electron microscopy of AlGaAs/GaAs quantum cascade laser structures. Journal of Microscopy, 268(3), 298-304. View this article in WRRO
- Preface to special issue on Microscopy of Semiconducting Materials 2017 (MSM-XX). J Microsc, 268(3), 221-224. View this article in WRRO
- Comparison of cross-sectional transmission electron microscope studies of thin germanium epilayers grown on differently oriented silicon wafers. Journal of Microscopy, 268(3), 288-297. View this article in WRRO
- Effective absorption correction for energy dispersive X-ray mapping in a scanning transmission electron microscope: analysing the local indium distribution in rough samples of InGaN alloy layers. Journal of Microscopy, 268(3), 248-253. View this article in WRRO
- Evidence of terbium and oxygen co-segregation in annealed AlN:Tb. Applied Physics Letters, 110(22). View this article in WRRO
- Study of phase separation in an InGaN alloy by electron energy loss spectroscopy in an aberration corrected monochromated scanning transmission electron microscope. Journal of Materials Research, 32(5), 983-995. View this article in WRRO
- Introduction. Journal of Materials Research, 32(5), 911-911. View this article in WRRO
- Investigation of phase separation in InGaN alloys by plasmon loss spectroscopy in a TEM. MRS Advances, 1(40), 2749-2756.
- Self-consistent method for quantifying indium content from X-ray spectra of thick compound semiconductor specimens in a transmission electron microscope. Journal of Microscopy, 262(2), 151-156. View this article in WRRO
- Automated background subtraction technique for electron energy‐loss spectroscopy and application to semiconductor heterostructures. Journal of Microscopy, 262(2), 157-166. View this article in WRRO
- Preface of 19th Microscopy of Semiconducting Materials conference. Journal of Microscopy, 262(2), 131-133. View this article in WRRO
- New pathways for improved quantification of energy-dispersive X-ray spectra of semiconductors with multiple X-ray lines from thin foils investigated in transmission electron microscopy. Journal of Microscopy, 260(3), 427-441. View this article in WRRO
- Defects, strain relaxation, and compositional grading in high indium content InGaN epilayers grown by molecular beam epitaxy. Journal of Applied Physics, 118(15), 155301-155301. View this article in WRRO
- Nanostructure and strain properties of core-shell GaAs/AlGaAs nanowires. Semiconductor Science and Technology, 30(11), 114012-114012. View this article in WRRO
- Combination of electron energy-loss spectroscopy and energy dispersive x-ray spectroscopy to determine indium concentration in InGaN thin film structures. Semiconductor Science and Technology, 30(11). View this article in WRRO
- Accurate measurement of atomic segregation to grain boundaries or to planar faults by analytical transmission electron microscopy. physica status solidi (c), 12(3), 310-313. View this article in WRRO
- Electron microscopy of quantum dots. Journal of Microscopy, 257(3), 171-178. View this article in WRRO
- Twinning in GaAs nanowires on patterned GaAs(111)B. Crystal Research and Technology, 50(1), 62-68. View this article in WRRO
- What environmental transmission electron microscopy measures and how this links to diffusivity: thermodynamics versus kinetics. Journal of Microscopy, 257(2), 87-91. View this article in WRRO
- Scanning transmission electron microscopy measurement of bismuth segregation in thin Ga(As,Bi) layers grown by molecular beam epitaxy. Crystal Research and Technology, 50(1), 38-42. View this article in WRRO
- How to best measure atomic segregation to grain boundaries by analytical transmission electron microscopy. Journal of Materials Science, 49(11), 3898-3908. View this article in WRRO
- Similarity of Stranski-Krastanow growth of Ge/Si and SiGe/Si (001). Journal of Applied Physics, 115(1).
- Homogeneous array of nanowire-embedded quantum light emitters.. Nano Lett, 13(3), 861-865.
- Lattice resolved annular dark-field scannning transmission electron microscopy of (Al,Ga)GaN/GaN layers for measuring segregation with sub-monolayer precision. Journal of Materials Science, 48, 2883-2892.
- Electron Microscopy and Analysis Group Conference 2011 (EMAG 2011). Journal of Physics: Conference Series, 371, 011001-011001.
- Characterization of InGaN/GaN epitaxial layers by aberration corrected TEM/STEM. Physica Status Solidi (C) Current Topics in Solid State Physics, 9(3-4), 546-549.
- Measurement of the Al content in AlGaN epitaxial layers by combined energy-dispersive X-ray and electron energy-loss spectroscopy in a transmission electron microscope. Physica Status Solidi. C: Current Topics in Solid State Physics, 9(3-4), 1079-1082.
- 17th International Conference on Microscopy of Semiconducting Materials 2011. Journal of Physics: Conference Series, 326, 011001-011001.
- High Repetition Rate Ti:Sapphire Laser Mode-Locked by InP Quantum-Dot Saturable Absorber. IEEE PHOTONIC TECH L, 23(21), 1603-1605.
- Room-Temperature GaAs/AlGaAs Quantum Cascade Lasers Grown by Metal-Organic Vapor Phase Epitaxy. IEEE PHOTONIC TECH L, 23(12), 774-776.
- High temperature λ∼4m In
0.7 Ga0.3 As/In0.34 Al0.66 As quantum cascade lasers grown by MOVPE. Electronics Letters, 47(9), 559-561. - Accurate calibration for the quantification of the Al content in AlGaN epitaxial layers by energy-dispersive X-ray spectroscopy in a Transmission Electron Microscope. 17TH INTERNATIONAL CONFERENCE ON MICROSCOPY OF SEMICONDUCTING MATERIALS 2011, 326.
- Quantification of series of X-ray spectra taken at different tilts in analytical transmission electron microscopy. 17TH INTERNATIONAL CONFERENCE ON MICROSCOPY OF SEMICONDUCTING MATERIALS 2011, 326.
- Nanoscale EELS analysis of elemental distribution and band-gap properties in AlGaN epitaxial layers. 17TH INTERNATIONAL CONFERENCE ON MICROSCOPY OF SEMICONDUCTING MATERIALS 2011, 326.
- GaAsBi atomic surface order and interfacial roughness observed by STM and TEM. 17TH INTERNATIONAL CONFERENCE ON MICROSCOPY OF SEMICONDUCTING MATERIALS 2011, 326.
- Investigation of boron implantation into silicon by quantitative energy-filtered transmission electron microscopy. 17TH INTERNATIONAL CONFERENCE ON MICROSCOPY OF SEMICONDUCTING MATERIALS 2011, 326.
- Electron Microscopy and Analysis Group Conference 2009. Journal of Physics: Conference Series, 241, 011001-011001.
- Electron microscopy of AlGaN-based multilayers for UV laser devices. Journal of Physics: Conference Series, 241.
- An improved approach to quantitative X-ray microanalysis in (S)TEM: Thickness dependent k-factors. Journal of Physics: Conference Series, 241.
- Probe position recovery for ptychographical imaging. Journal of Physics: Conference Series, 241.
- Quantification of carbon contamination under electron beam irradiation in a scanning transmission electron microscope and its suppression by plasma cleaning. Journal of Physics: Conference Series, 241.
- Study of the effect of annealing of In(Ga)As quantum dots. Journal of Physics: Conference Series, 241.
- Study of annealed InAs/GaAs quantum dot structures. Journal of Physics: Conference Series, 209.
- Measuring the contrast in annular dark field STEM images as a function of camera length. Journal of Physics: Conference Series, 241.
- GaN, AlGaN, HfO
2 based radial heterostructure nanowires. Journal of Physics: Conference Series, 209. - Quantitative investigation of the onset of islanding in strained layer epitaxy of InAs/GaAs by X-ray mapping in STEM. Journal of Physics: Conference Series, 209.
- TEM analysis of Ge-on-Si MOSFET structures with HfO
2 dielectric for high performance PMOS device technology. Journal of Physics: Conference Series, 209. - Comparison of experimental and theoretical X-ray intensities from (In)GaAs specimens investigated by energy-dispersive X-ray spectroscopy in a transmission electron microscope. Journal of Physics: Conference Series, 209.
- Influence of thick crystal effects on ptychographic image reconstruction with moveable illumination.. Ultramicroscopy, 109(10), 1263-1275.
- 1.55 mu m InAs quantum dots grown on a GaAs substrate using a GaAsSb metamorphic buffer layer. APPL PHYS LETT, 92(11).
- Electro-assisted photo-luminescence of colloidal germanium nanoparticles. Zeitschrift fur Physikalische Chemie, 221(3), 377-386.
- Quantitative microstructural and spectroscopic investigation of inversion domain boundaries in sintered zinc oxide ceramics doped with iron oxide. International Journal of Materials Research, 97(7), 934-942.
- Laser-Assisted Synthesis of Au−Ag Alloy Nanoparticles in Solution. The Journal of Physical Chemistry Part B, 110(6), 2549-2554.
- High ultimate tensile stress in nano-grained superelastic NiTi thin films. MAT SCI ENG A-STRUCT, 415(1-2), 304-308.
- Combinatorial investigation of the isolated nanoparticle to coalescent layer transition in a gradient sputtered gold nanoparticle layer on top of polystyrene. Applied Physics Letters, 88(2), 1-3.
- Structural and magnetic characteristics of FeCo thin films modified by combinatorial ion implantation. Thin Solid Films, 495(1-2), 169-174.
- Linear least-squares fit evaluation of series of analytical spectra from planar defects: Extension and possible implementations in scanning transmission electron microscopy. Journal of Microscopy, 223(2), 165-170.
- A new experimental procedure to quantify annular dark field images in scanning transmission electron microscopy. Journal of Microscopy, 221(2), 137-144.
- Structure of PtFe/Fe double-period multilayers investigated by X-ray diffraction, reflectivity, diffuse scattering and TEM. Applied Surface Science, 253(1 SPEC. ISS.), 128-132.
- First experimental test of a new monochromated and aberration-corrected 200 kV field-emission scanning transmission electron microscope. Ultramicroscopy, 106(11-12 SPEC. ISS.), 963-969.
- A novel method of analytical transmission electron microscopy for measuring highly accurately segregation to special grain boundaries or planar interfaces. Microchimica Acta, 155(1-2), 313-318.
- Preliminary results from the first monochromated and aberration corrected 200-kV field-emission scanning transmission electron microscope. Microscopy and Microanalysis, 12(6), 498-505.
- Critical assessment of the speckle statistics in fluctuation electron microscopy and comparison to electron diffraction. Ultramicroscopy, 104(3-4), 206-219.
- Photofragmentation of Phase-Transferred Gold Nanoparticles by Intense Pulsed Laser Light. The Journal of Physical Chemistry Part B, 109(33), 15735-15740.
- StripeTEM as a method of calculating chemical profiles across interfaces between solids or core-shell structures using electron energy-loss spectroscopic profiling. International Journal of Materials Research, 96(5), 429-437.
- Influence of Intense Pulsed Laser Irradiation on Optical and Morphological Properties of Gold Nanoparticle Aggregates Produced by Surface Acid−Base Reactions. Langmuir, 21(10), 4249-4253.
- StripeTEM as a method of calculating chemical profiles across interfaces between solids or core-shell structures using electron energy-loss spectroscopic profiling. Zeitschrift fuer Metallkunde/Materials Research and Advanced Techniques, 96(5), 429-437.
- Diffusion and segregation effects in doped manganite/titanate heterostructures. Applied Physics Letters, 84(19), 3882-3884.
- Twin boundaries in zinc oxide with additions of gallium oxide. Interface Science, 12(2-3), 213-226.
- A new method to measure small amounts of solute atoms on planar defects and application to inversion domain boundaries in doped zinc oxide. Interface Science, 12(2-3), 267-275.
- Development of a new analytical electron microscopy technique to quantify the chemistry of planar defects and to measure accurately solute segregation to grain boundaries. Journal of Microscopy, 215(2), 191-202.
- Atomic structure of basal-plane inversion boundaries in SnO2-doped ZnO. Microscopy and Microanalysis, 9(S03), 286-287.
- Barium diffusion and calcium segregation in manganite thin films. Microscopy and Microanalysis, 9(SUPPL. 3), 268-269.
- Behavior of basic refractories at high temperatures in steelmaking processes - Thermodynamics and implications for the usability of olivine as refractory material. European Journal of Mineralogy, 15(1), 193-205.
- Electron energy-loss spectroscopic profiling of thin film structures: 0.39 nm line resolution and 0.04 eV precision measurement of near-edge structure shifts at interfaces. Ultramicroscopy, 96(3-4), 401-411.
- Influence of pumping and inherent laser light on properties and degradation of ZnMgSSe/ZnSe quantum well heterostructures. Physica Status Solidi (A) Applied Research, 195(1 SPEC), 188-193.
- Atomic structure of basal-plane inversion boundaries in SnO
2 -doped ZnO. Microscopy and Microanalysis, 9(SUPPL. 3), 286-287. - Fluctuation electron microscopy on a-Ge and polycrystalline gold. Microscopy and Microanalysis, 9(SUPPL. 3), 152-153.
- Structural and doping effects in the half-metallic double perovskite A
2 CrWO6 (A=Sr, Ba, and Ca). Physical Review B - Condensed Matter and Materials Physics, 68(14). - Combinatorial thin film synthesis of NiMnAl magnetic shape memory alloys using MBE technique. Materials Research Society Symposium - Proceedings, 785, 57-64.
- Strategies for investigating core-shell particles by energy-filtered transmission electron microscopy. Microscopy and Microanalysis, 9(SUPPL. 3), 98-99.
- Stranski-Krastanow transition and epitaxial island growth. PHYS REV B, 66(8).
- Microstructure and magnetoresistance of epitaxial films of the layered perovskite La2-2xSr1+2xMn2O7 (x = 0.3 and 0.4). PHYS REV B, 65(18).
- Exit Wave Reconstruction and Elemental Mapping of Twin Boundaries in the System Zno - Ga2O3. Microscopy and Microanalysis, 7(S2), 290-291.
- Nature of the Stranski-Krastanow transition during epitaxy of InGaAs on GaAs.. Phys Rev Lett, 86(11), 2381-2384.
- Structure and Chemistry of Basal-Plane Inversion Boundaries in Antimony Oxide-Doped Zinc Oxide. Journal of the American Ceramic Society, 84(11), 2657-2668.
- Auger depth profile analysis and EFTEM analysis of annealed Ti/Al-contacts on Si-doped GaN. Applied Surface Science, 179(1-4), 213-221.
- Thermal Stability of ZnMgSSe/ZnSe Laser Heterostructures. Physica Status Solidi (A) Applied Research, 185(2), 301-308.
- Measurement of diffusion lengths in quaternary semiconducting thin layers by spectrum imaging. Physica B: Condensed Matter, 308-310, 1161-1164.
- Study of sulphur diffusion in ZnMgSSe/ZnSe quantum wells by energy-loss imaging in a transmission electron microscope. Physica Status Solidi (A) Applied Research, 180(1), 351-356.
- Diffusion processes in strained silicon germanium island structures. Diffusion and Defect Data. Pt A Defect and Diffusion Forum, 183, 53-60.
- Development of a technique for a quantitative study of the order and composition of an iron-palladium alloy on the nanometre scale in an electron microscope with imaging filter. Philosophical Magazine Letters, 79(1), 31-39.
- A quantitative study of compositional profiles of chemical vapour-deposited strained silicon-germanium/silicon layers by transmission electron microscopy. Journal of Crystal Growth, 197(1-2), 113-128.
- Transmission electron microscopy study of Si δ-doped GaAs/AlGaAs/InGaAs/GaAs pseudomorphic high electron mobility transistor structures. Thin Solid Films, 307(1-2), 6-9.
- Diffusion and surface segregation in thin SiGe/Si layers studied by scanning transmission electron microscopy. Defect and Diffusion Forum, 143-147, 1135-1140.
- Maxwell's demon and data analysis - Discussion. PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES, 354(1719), 2709-2711.
- Changes of the local oxygen content and ordering at twin boundaries of hi superconductors. Physical Review B - Condensed Matter and Materials Physics, 54(22), 16234-16237.
- Quantitative characterization of AlAs/GaAs interfaces by high-resolution transmission electron microscopy along the 〈100〉 and the 〈110〉 projection. Applied Physics A Solids and Surfaces, 57(5), 393-400.
- Preface to the special issue on Microscopy of Semiconducting Materials 2023. Journal of Microscopy.
- The evolution of indium precipitation in gallium focused ion beam prepared samples of InGaAs/InAlAs quantum wells under electron beam irradiation. Journal of Microscopy.
- Chemical Structure Comparison via Scanning Electron Microscopy of Spent Commercial Nickel–Metal Hydride Batteries. Materials, 16(17), 5761-5761.
- Atomic Plane Misorientation Assisted Crystalline Quality Improvement in Epitaxial Growth of AlN on a Nanopatterned Sapphire (0001) Surface for Deep Ultraviolet Photoelectric Devices. ACS Applied Nano Materials.
- X-ray mapping in a scanning transmission electron microscope of InGaAs quantum dots with embedded fractional monolayers of aluminium. Semiconductor Science and Technology. View this article in WRRO
Chapters
- Automated EELS Core-Loss Edge Detection for Quantification of the Chemical Composition of Nano-Structured Semiconductors, Encyclopedia of Materials: Electronics (pp. V3-605-V3-618).
- Transmission Electron Microscopy of Nanostructures, Microscopy Methods in Nanomaterials Characterization (pp. 105-134). Elsevier
- Controlled quantum dot formation on focused ion beam patterned GaAs substrates In Wang ZM (Ed.), FIB Nanostructures (pp. 299-314). Cham, Switzerland: Springer.
Conference proceedings papers
- Measuring grain boundary segregation: tomographic atom probe field ion microscopy (APFIM) vs. analytical scanning transmission electron microscopy (STEM). Journal of Physics: Conference Series, Vol. 1190(1). Thessaloniki, Greece, 24 June 2018 - 29 June 2018. View this article in WRRO
- Influence of background subtraction and deconvolution on calculation of EELS core‐loss intensities (pp 891-892)
- Self-consistent absorption correction for quantitative energy- dispersive X-ray spectroscopy of InGaN layers in analytical transmission electron microscopy. Journal of Physics: Conference Series, Vol. 644 (pp 012006-012006) View this article in WRRO
- Development of automated background subtraction technique for electron energy-loss spectroscopy. http://www.mmc2015.org.uk/ (pp P.4027-P.4027). Manchester, 29 June 2015 - 2 July 2015.
- Core-loss edge detection and background subtraction techniques for EELS. abstract booklet online(poster #3) (pp 13-13). Coventry, 15 October 2014 - 16 October 2014.
- The influence of emitter conditioning on the performance of a tungsten <111> cold field emission gun operating at 300 kV. Journal of Physics: Conference Series, Vol. 522(1)
- Towards the structure of rare earth luminescence centres - terbium doped aluminium nitride as an example system. Journal of Physics: Conference Series, Vol. 471 (pp 012032-1-012032-4). Bristol, 7 April 2013 - 11 April 2013.
- Study of site controlled quantum dot formation on focused ion beam patterned GaAs substrates. Journal of Physics: Conference Series, Vol. 471 (pp 012047-1-012047-4). Bristol, 7 April 2013 - 11 April 2013.
- Investigation of growth of thin layers of perovskite on native silicon dioxide by a combination of atomic force microscopy and transmission electron microscopy. Journal of Physics: Conference Series, Vol. 471 (pp 012037-1-012037-4). Bristol, 7 April 2013 - 11 April 2013.
- Calibration of thickness-dependent k-factors for germanium X-ray lines to improve energy-dispersive X-ray spectroscopy of SiGe layers in analytical transmission electron microscopy. Journal of Physics: Conference Series, Vol. 471 (pp 012031-1-012031-6). Bristol, 7 April 2013 - 11 April 2013.
- GaN-based radial heterostructure nanowires by MBE and ALD. Journal of Physics: Conference Series, Vol. 471 (pp 012039-1-012039-4). Bristol, 7 April 2013 - 11 April 2013.
- Self-consistent absorption corrections for low-energy X-ray lines in energy-dispersive X-ray spectroscopy. Journal of Physics: Conference Series, Vol. 371 (pp 012063-1-012063-4). Birmingham, UK, 6 September 2011 - 9 September 2011.
- A TEM study of Ge-on-(111)Si structures for potential use in high performance PMOS device technology. 17TH INTERNATIONAL CONFERENCE ON MICROSCOPY OF SEMICONDUCTING MATERIALS 2011, Vol. 326
- Comparison of the contrast in conventional and lattice resolved ADF STEM images of InGaAs/GaAs structures using different camera lengths. 17TH INTERNATIONAL CONFERENCE ON MICROSCOPY OF SEMICONDUCTING MATERIALS 2011, Vol. 326
- Analysis of partially oxidised epitaxial silicon mono-layers on germanium virtual substrates using aberration corrected scanning transmission electron microscopy. 17TH INTERNATIONAL CONFERENCE ON MICROSCOPY OF SEMICONDUCTING MATERIALS 2011, Vol. 326
- STEM imaging of InP/AlGaInP quantum dots. Journal of Physics: Conference Series, Vol. 245 (pp 012087). Nottingham
- TEM analysis of Si-passivated Ge-on-Si MOSFET structures for high performance PMOS device technology. Journal of Physics: Conference Series, Vol. 241
- Simple method to improve quantification accuracy of energy-dispersive X-ray spectroscopy in an analytical transmission electron microscope by specimen tilting. EMC2008- 14th European Microscopy Congress, Vol. 2 (Materials Science) (pp 375-376). Berlin, 1 September 2008 - 5 September 2008.
- Comparison of monochromated electron energy-loss with X-ray absorption near-edge spectra: ELNES vs. XANES. EMC2008- 14th European Microscopy Congress, Vol. 1 (Instrumentation and Methods) (pp 65-66). Berlin, 1 September 2008 - 5 September 2008.
- Measuring coherence in an electron beam for imaging. EMC2008- 14th European Microscopy Congress, Vol. 1 (Instrumentation and Methods) (pp 165-166). Berlin, 1 September 2008 - 5 September 2008.
- Investigating the influence of dynamic scattering on ptychographical iterative techniques. EMC2008- 14th European Microscopy Congress, Vol. 1 (Instrumentation and Methods) (pp 723-724). Berlin, 1 September 2008 - 5 September 2008.
- Flutuation electron microscopy on a-Ge and polycrystalline gold. Microscopy and Microanalysis, Vol. 9(Suppl. 3) (pp 152-153). Cambridge, 7 September 2003 - 12 September 2003.
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- Measurement of oxygen disorder and nano-twin microstructure associated with columnar defects in YBa2Cu3O7-x. Materials Research Society Fall Meeting, Vol. 540 (pp 267-272). Boston (book), cambridge (on-line), 1998 - 1998.
- Joint plasmon and core-loss fitting for electron energy loss spectroscopy of InGaN (pp 893-894)
- Sub-diffraction limited imaging of nano-rulers using Structured Illumination Microscopy. Frontiers in BioImaging, 14 July 2016 - 15 July 2016.
- Systematic Study of Background Subtraction Techniques for EELS. http://emag2016.iopconfs.org/, 6 April 2016 - 8 April 2016.
Patents
Reports
Theses / Dissertations
- Preface: Microscopy of Semiconducting Materials 2015. Bristol: IOP Publishing.
- Teaching activities
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- EEE345 'Engineering Electromagnetics'
- EEE6233 'Physical Principles of Imaging: Radiation-Matter Interaction'
- Professional activities and memberships
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- Reader in Advanced Electron Microscopy
- Departmental Tutor for Postgraduate Research Students
- Research students
Student Degree Status Primary/Secondary Guo R PhD Current Primary Luo P PhD Current Secondary Yan H PhD Current Secondary Wang X PhD Graduated Primary Amari H PhD Graduated Primary Angadi V PhD Graduated Primary Parri M C PhD Graduated Primary Qiu Y PhD Graduated Primary Taghi Khani A PhD Graduated Primary Zhang H PhD Graduated Primary