Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 1990
This Paper summarizes some of the improvements made at the nuclear microprobe facility in Lund. T... more This Paper summarizes some of the improvements made at the nuclear microprobe facility in Lund. The analytical facility is briefly described, and problems concerning quantification are discussed. The external beam facility has been applied to the analysis of both historical documents and geological materials.
In 2016, the EC Joint Research Centre organised an interlaboratory comparison. • The exercise was... more In 2016, the EC Joint Research Centre organised an interlaboratory comparison. • The exercise was conducted in the frame of MetroERM EMRP project with code ENV57. • 67 laboratories participated by measuring 137 Cs, 134 Cs and 131 I in air filters. • 56 laboratories reported within ± 20% from the reference value for 137 Cs and 134 Cs. • Due to a complication, only 20 laboratories reported results within ± 20% for 131 I.
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, Mar 1, 1991
The overall technical status of the Lund nuclear microprobe is presented. Several parts of the in... more The overall technical status of the Lund nuclear microprobe is presented. Several parts of the instrument have been replaced by newly developed systems. In this paper the main emphasis is directed to a newly installed, versatile specimen chamber. The special characteristics are: very quick opening and sample-changing procedures, many samples of varying sizes can be housed simultaneously and several detector
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, Apr 1, 1990
and ~e~~na~~~, ~~~lle~~~an 14. S-223 62 Cundy Sweden The status of the Lund Nuclear Microprobe is... more and ~e~~na~~~, ~~~lle~~~an 14. S-223 62 Cundy Sweden The status of the Lund Nuclear Microprobe is presented. Several parts of the instrument have been replaced by newly developed systems. The presentation includes descriptions uf an achromatic focusing system. a YMEbus scanning and data acquisition system and data handling techniques. Several applications are discussed. Finally, a microbeam in air setup is described.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1998
Amorphous hydrogenated boron carbide thin films were analyzed using the (a. p) reaction on boron,... more Amorphous hydrogenated boron carbide thin films were analyzed using the (a. p) reaction on boron, (a, a) backscattering on carbon and the ("N, ay) resonant reaction on hydrogen as part of an investigation of superhard coatings. The films were deposited on aluminium-silicon-magnesium substrates by Physical Vapor Deposition (PVD)-Magnetron Sputtering in an argon gas atmosphere with the admixture of methane (CH4) gas using B4C as starting material. The elemental composition was determined by the concentration ratio of boron and carbon. obtained from the simultaneously recorded boron and carbon spectra, and the separately measured hydrogen profile. An important finding was the irradiation stability, the homogeneous depth distribution and the high uptake of hydrogen which open up the possibility for the production of a new hydrogen standard.
CoSi2 exhibits the features of low resistivity and stability at elevated temperatures which make ... more CoSi2 exhibits the features of low resistivity and stability at elevated temperatures which make it interesting to employ for metallization on GaAs. The interfacial reactions in GaAs samples with thin film overlayers of Si and Co [Si(220 nm)/Co(50 nm)/(〈100〉-GaAs)] were studied using x-ray diffraction, scanning electron microscopy, x-ray photoelectron spectroscopy, and mass and energy dispersive recoil spectrometry. Samples were vacuum furnace annealed for time periods between 1 and 8 h at temperatures ranging from 300 to 700 °C. It was found that a CoSi2 layer formed without observable reaction with the substrate at 500 °C and above. The excess Si (Si/Co atomic ratio of 2.41) remained near the surface as elemental Si and as SiO2 for the 500 and 600 °C annealings. For the 700 °C annealing the excess near-surface Si was not observed.
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, Mar 1, 1994
Mass and energy-dispersive recoil spectrometry has recently reached the state of development wher... more Mass and energy-dispersive recoil spectrometry has recently reached the state of development where it is possible to separately characterise Ga and As in GaAs samples. Since it is possible to simultaneously characterise several elements (light as well as heavy), e.g. C, 0, Si, Co, Ga and As, the technique is suited for examining the depth distribution of metallisation contacts on GaAs. In a Swedish-Australian collaboration a recoil detector telescope was attached to a beamline of the FN tandem accelerator "ANTARES", at Lucas Heights Research Laboratories, Australia. In the measurements presented here, 1271'0f at an energy of 77 MeV was employed to analyse GaAs samples with thin film overlayers-Sic220 nm)/Co(50 nm)/(lOO)-GaAs. A reference sample and samples annealed at 300 to 600°C were analysed. The measurements showed that Co%, is formed during annealing at and above 500°C with no detectable reaction between the GaAs-substrate and the Cc&i, overlayer.
Mass and energy-dispersive recoil spectrometry, where the recoil energy is derived from the recoi... more Mass and energy-dispersive recoil spectrometry, where the recoil energy is derived from the recoil time of flight, has been used to characterize the depth distribution of Al, Ga, and As in an AlxGa(1−x)As quantum-well structure. Signals characterizing the Al, Ga, and As distribution with good separation between Ga and As (average crosstalk <2%) could be obtained from depths less than 560 nm from the surface. The depth resolution of the As signal at the surface was 16 nm FWHM, which is considerably better than achieved using a silicon particle detector (34 nm).
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, May 1, 1993
The development of a dedicated facility for nuclear microprobe analysis and the experiences from ... more The development of a dedicated facility for nuclear microprobe analysis and the experiences from using it are discussed. The general properties of the present Lund nuclear microprobe will be described and the advantages of using a dedicated accelerator discussed.
Our study aimed to understand the origin of elevated (>100 mBqL–1) gross alpha activity me... more Our study aimed to understand the origin of elevated (>100 mBqL–1) gross alpha activity measured in groundwater-derived drinking water in the vicinity of the Sopron Mountains and Lake Fertő (Neusiedl). Water samples from 10 springs and 7 water wells were analyzed for major ions and trace elements. Total U and 226Ra activity concentrations were determined by alpha spectrometry using Nucfilm discs, and 222Rn activity was measured by liquid scintillation counting. 234U/238U ratio was determined by ICP-MS and alpha spectrometry. Additionally, δ2H and δ18O measurements were performed. To get an insight into the dynamics of the groundwater flow system and to better understand the radionuclide mobilization and transport processes, the geochemical results were evaluated in the groundwater flow system context.Uranium activity was measured up to 540 mBqL–1, thus it can be concluded that dissolved uranium causes the previously measured elevated gross alpha values, though no health risk arises from drinking water consumption. The occurrence of dissolved uranium can be explained by oxidizing conditions that are prevalent along local flow systems and in recharge areas. The relatively short residence time of water, thus the presence of local flow systems is indicated by δ18O (-11.96 to -7.17‰) and δ2H values (-83.4 to -52.6‰). Spring samples have lower uranium activity (up to 93 mBqL–1) than groundwater samples (up to 540 mBqL–1) which can be explained by the longer residence time of water. Uranium is transported along flow paths under oxidizing conditions and the longer the flow route the higher the uranium concentration.This topic is part of a project that has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement No. 810980. Besides, the research was funded by the National Multidisciplinary Laboratory for Climate Change, RRF-2.3.1-21-2022-00014 project project. Some radioactivity measurements were supported by the European Commission’s Joint Research Centre (JRC) – Research Infrastructure Access Agreement No. 36227-1/2021-1-RD-EUFRAT-RADMET.
Separation of mass overlapped recoil spectometry data using Ryan and Jamieson's dynamic analy... more Separation of mass overlapped recoil spectometry data using Ryan and Jamieson's dynamic analysis method
Preliminary results are presented from a study of transition metal/lnP reactions using mass and e... more Preliminary results are presented from a study of transition metal/lnP reactions using mass and energy dispersive recoil spectrometry. 50 nm films of Ni, Pd and Pt were evaporated on InP substrates, heat treated in vacuum and subsequently analysed with X-ray diffraction and mass and energy dispersive recoil spectrometry using 77 MeV'*' I"+ ions as projectiles. The unique information on the elemental distributions in the surface layers which can be obtained using the latter technique has allowed us to follow the progress of the solid state reactions. These reactions are quite different for the three metals studied, with significant P loss in the Pd/lnP case.
Nuclear Instruments and Methods in Physics Research, Dec 1, 1994
Mass and energy dispersive Recoil Spectrometry (RS) has been employed to study stoichiometric var... more Mass and energy dispersive Recoil Spectrometry (RS) has been employed to study stoichiometric variations in AI,Ga,_ x As layers. Quantitative determination of x is an important problem in the production of device materials which is not easily solved with standard techniques. Rutherford Backscattering Spectrometry (RBS) has been used extensively in semiconductor research but overlap of signals in the backscattered ion spectrum is an important limitation in the analysis of materials such as A1 xGa,_ x As which contain elements of low and similar masses. Particle Induced X-ray Emission (PIXE) analysis has good elemental resolution for this class of materials but provides little depth resolution. RS enables the determination of separate energy spectra for individual or small groups of isotopes. This allows it to be used in many situations where RBS is inappropriate. It employs a heavy ion beam to cause constituent nuclei to recoil from the target, and a Time of Flight and Energy (ToF-E) detector to detect these recoiling nuclei. Appropriate mass selection of the ToF-E data allows the determination of depth distributions for each element.
GaAs samples with a 100-nm-Co overlayer that had been subjected to rapid thermal annealing for 60... more GaAs samples with a 100-nm-Co overlayer that had been subjected to rapid thermal annealing for 60 s at temperatures of 400–650 °C were analyzed using mass and energy dispersive recoil spectrometry. Separate characterizations of C, O, Co, Ga, and As depth distributions were performed. Both Ga and As had migrated to the surface at anneal temperatures higher than 450 °C. In a sample annealed at 650 °C, a clear enrichment of Ga in the outer 35 nm was observed. The composition for various depth intervals was determined for different temperatures. From Arrhenius plots, apparent activation energies were estimated to be about 0.6 eV for phase formation and 1.3 eV for diffusion. X-ray diffraction indicated that CoGa and CoAs phases were present in all the annealed samples. Scanning electron microscopy showed the surface to be reticulated after heat treatment, with grain growth at higher temperatures.
Groundwater quality constantly evolves through rock–water interactions, which can enrich groundwa... more Groundwater quality constantly evolves through rock–water interactions, which can enrich groundwater with undesirable elements such as naturally occurring radionuclides. The aim of this study was to understand the cause of gross alpha activity exceeding the screening value of 0.1 Bq L−1 measured in groundwater-derived drinking water in the vicinity of a metamorphic outcrop in Hungary. As groundwater quality is strongly dependent on the properties of groundwater flow systems, environmental tracers (δ2H and δ18O composition, 226Ra, 222Rn, total U activity concentration, and 234U/238U ratio) and hydraulic evaluation were applied to understand groundwater dynamics. The collected groundwater samples had total U activities up to 540 mBq L−1, which translates into an indicative dose below the drinking water parametric value. However, in the presence of dissolved uranium, the δ2H (−52.6–(−83.4)) and δ18O (−7.17–(−11.96)) values led to the conclusion that local flow systems were sampled that...
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, 1990
This Paper summarizes some of the improvements made at the nuclear microprobe facility in Lund. T... more This Paper summarizes some of the improvements made at the nuclear microprobe facility in Lund. The analytical facility is briefly described, and problems concerning quantification are discussed. The external beam facility has been applied to the analysis of both historical documents and geological materials.
In 2016, the EC Joint Research Centre organised an interlaboratory comparison. • The exercise was... more In 2016, the EC Joint Research Centre organised an interlaboratory comparison. • The exercise was conducted in the frame of MetroERM EMRP project with code ENV57. • 67 laboratories participated by measuring 137 Cs, 134 Cs and 131 I in air filters. • 56 laboratories reported within ± 20% from the reference value for 137 Cs and 134 Cs. • Due to a complication, only 20 laboratories reported results within ± 20% for 131 I.
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, Mar 1, 1991
The overall technical status of the Lund nuclear microprobe is presented. Several parts of the in... more The overall technical status of the Lund nuclear microprobe is presented. Several parts of the instrument have been replaced by newly developed systems. In this paper the main emphasis is directed to a newly installed, versatile specimen chamber. The special characteristics are: very quick opening and sample-changing procedures, many samples of varying sizes can be housed simultaneously and several detector
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, Apr 1, 1990
and ~e~~na~~~, ~~~lle~~~an 14. S-223 62 Cundy Sweden The status of the Lund Nuclear Microprobe is... more and ~e~~na~~~, ~~~lle~~~an 14. S-223 62 Cundy Sweden The status of the Lund Nuclear Microprobe is presented. Several parts of the instrument have been replaced by newly developed systems. The presentation includes descriptions uf an achromatic focusing system. a YMEbus scanning and data acquisition system and data handling techniques. Several applications are discussed. Finally, a microbeam in air setup is described.
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1998
Amorphous hydrogenated boron carbide thin films were analyzed using the (a. p) reaction on boron,... more Amorphous hydrogenated boron carbide thin films were analyzed using the (a. p) reaction on boron, (a, a) backscattering on carbon and the ("N, ay) resonant reaction on hydrogen as part of an investigation of superhard coatings. The films were deposited on aluminium-silicon-magnesium substrates by Physical Vapor Deposition (PVD)-Magnetron Sputtering in an argon gas atmosphere with the admixture of methane (CH4) gas using B4C as starting material. The elemental composition was determined by the concentration ratio of boron and carbon. obtained from the simultaneously recorded boron and carbon spectra, and the separately measured hydrogen profile. An important finding was the irradiation stability, the homogeneous depth distribution and the high uptake of hydrogen which open up the possibility for the production of a new hydrogen standard.
CoSi2 exhibits the features of low resistivity and stability at elevated temperatures which make ... more CoSi2 exhibits the features of low resistivity and stability at elevated temperatures which make it interesting to employ for metallization on GaAs. The interfacial reactions in GaAs samples with thin film overlayers of Si and Co [Si(220 nm)/Co(50 nm)/(〈100〉-GaAs)] were studied using x-ray diffraction, scanning electron microscopy, x-ray photoelectron spectroscopy, and mass and energy dispersive recoil spectrometry. Samples were vacuum furnace annealed for time periods between 1 and 8 h at temperatures ranging from 300 to 700 °C. It was found that a CoSi2 layer formed without observable reaction with the substrate at 500 °C and above. The excess Si (Si/Co atomic ratio of 2.41) remained near the surface as elemental Si and as SiO2 for the 500 and 600 °C annealings. For the 700 °C annealing the excess near-surface Si was not observed.
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, Mar 1, 1994
Mass and energy-dispersive recoil spectrometry has recently reached the state of development wher... more Mass and energy-dispersive recoil spectrometry has recently reached the state of development where it is possible to separately characterise Ga and As in GaAs samples. Since it is possible to simultaneously characterise several elements (light as well as heavy), e.g. C, 0, Si, Co, Ga and As, the technique is suited for examining the depth distribution of metallisation contacts on GaAs. In a Swedish-Australian collaboration a recoil detector telescope was attached to a beamline of the FN tandem accelerator "ANTARES", at Lucas Heights Research Laboratories, Australia. In the measurements presented here, 1271'0f at an energy of 77 MeV was employed to analyse GaAs samples with thin film overlayers-Sic220 nm)/Co(50 nm)/(lOO)-GaAs. A reference sample and samples annealed at 300 to 600°C were analysed. The measurements showed that Co%, is formed during annealing at and above 500°C with no detectable reaction between the GaAs-substrate and the Cc&i, overlayer.
Mass and energy-dispersive recoil spectrometry, where the recoil energy is derived from the recoi... more Mass and energy-dispersive recoil spectrometry, where the recoil energy is derived from the recoil time of flight, has been used to characterize the depth distribution of Al, Ga, and As in an AlxGa(1−x)As quantum-well structure. Signals characterizing the Al, Ga, and As distribution with good separation between Ga and As (average crosstalk <2%) could be obtained from depths less than 560 nm from the surface. The depth resolution of the As signal at the surface was 16 nm FWHM, which is considerably better than achieved using a silicon particle detector (34 nm).
Nuclear Instruments & Methods in Physics Research Section B-beam Interactions With Materials and Atoms, May 1, 1993
The development of a dedicated facility for nuclear microprobe analysis and the experiences from ... more The development of a dedicated facility for nuclear microprobe analysis and the experiences from using it are discussed. The general properties of the present Lund nuclear microprobe will be described and the advantages of using a dedicated accelerator discussed.
Our study aimed to understand the origin of elevated (>100 mBqL–1) gross alpha activity me... more Our study aimed to understand the origin of elevated (>100 mBqL–1) gross alpha activity measured in groundwater-derived drinking water in the vicinity of the Sopron Mountains and Lake Fertő (Neusiedl). Water samples from 10 springs and 7 water wells were analyzed for major ions and trace elements. Total U and 226Ra activity concentrations were determined by alpha spectrometry using Nucfilm discs, and 222Rn activity was measured by liquid scintillation counting. 234U/238U ratio was determined by ICP-MS and alpha spectrometry. Additionally, δ2H and δ18O measurements were performed. To get an insight into the dynamics of the groundwater flow system and to better understand the radionuclide mobilization and transport processes, the geochemical results were evaluated in the groundwater flow system context.Uranium activity was measured up to 540 mBqL–1, thus it can be concluded that dissolved uranium causes the previously measured elevated gross alpha values, though no health risk arises from drinking water consumption. The occurrence of dissolved uranium can be explained by oxidizing conditions that are prevalent along local flow systems and in recharge areas. The relatively short residence time of water, thus the presence of local flow systems is indicated by δ18O (-11.96 to -7.17‰) and δ2H values (-83.4 to -52.6‰). Spring samples have lower uranium activity (up to 93 mBqL–1) than groundwater samples (up to 540 mBqL–1) which can be explained by the longer residence time of water. Uranium is transported along flow paths under oxidizing conditions and the longer the flow route the higher the uranium concentration.This topic is part of a project that has received funding from the European Union’s Horizon 2020 Research and Innovation Programme under grant agreement No. 810980. Besides, the research was funded by the National Multidisciplinary Laboratory for Climate Change, RRF-2.3.1-21-2022-00014 project project. Some radioactivity measurements were supported by the European Commission’s Joint Research Centre (JRC) – Research Infrastructure Access Agreement No. 36227-1/2021-1-RD-EUFRAT-RADMET.
Separation of mass overlapped recoil spectometry data using Ryan and Jamieson's dynamic analy... more Separation of mass overlapped recoil spectometry data using Ryan and Jamieson's dynamic analysis method
Preliminary results are presented from a study of transition metal/lnP reactions using mass and e... more Preliminary results are presented from a study of transition metal/lnP reactions using mass and energy dispersive recoil spectrometry. 50 nm films of Ni, Pd and Pt were evaporated on InP substrates, heat treated in vacuum and subsequently analysed with X-ray diffraction and mass and energy dispersive recoil spectrometry using 77 MeV'*' I"+ ions as projectiles. The unique information on the elemental distributions in the surface layers which can be obtained using the latter technique has allowed us to follow the progress of the solid state reactions. These reactions are quite different for the three metals studied, with significant P loss in the Pd/lnP case.
Nuclear Instruments and Methods in Physics Research, Dec 1, 1994
Mass and energy dispersive Recoil Spectrometry (RS) has been employed to study stoichiometric var... more Mass and energy dispersive Recoil Spectrometry (RS) has been employed to study stoichiometric variations in AI,Ga,_ x As layers. Quantitative determination of x is an important problem in the production of device materials which is not easily solved with standard techniques. Rutherford Backscattering Spectrometry (RBS) has been used extensively in semiconductor research but overlap of signals in the backscattered ion spectrum is an important limitation in the analysis of materials such as A1 xGa,_ x As which contain elements of low and similar masses. Particle Induced X-ray Emission (PIXE) analysis has good elemental resolution for this class of materials but provides little depth resolution. RS enables the determination of separate energy spectra for individual or small groups of isotopes. This allows it to be used in many situations where RBS is inappropriate. It employs a heavy ion beam to cause constituent nuclei to recoil from the target, and a Time of Flight and Energy (ToF-E) detector to detect these recoiling nuclei. Appropriate mass selection of the ToF-E data allows the determination of depth distributions for each element.
GaAs samples with a 100-nm-Co overlayer that had been subjected to rapid thermal annealing for 60... more GaAs samples with a 100-nm-Co overlayer that had been subjected to rapid thermal annealing for 60 s at temperatures of 400–650 °C were analyzed using mass and energy dispersive recoil spectrometry. Separate characterizations of C, O, Co, Ga, and As depth distributions were performed. Both Ga and As had migrated to the surface at anneal temperatures higher than 450 °C. In a sample annealed at 650 °C, a clear enrichment of Ga in the outer 35 nm was observed. The composition for various depth intervals was determined for different temperatures. From Arrhenius plots, apparent activation energies were estimated to be about 0.6 eV for phase formation and 1.3 eV for diffusion. X-ray diffraction indicated that CoGa and CoAs phases were present in all the annealed samples. Scanning electron microscopy showed the surface to be reticulated after heat treatment, with grain growth at higher temperatures.
Groundwater quality constantly evolves through rock–water interactions, which can enrich groundwa... more Groundwater quality constantly evolves through rock–water interactions, which can enrich groundwater with undesirable elements such as naturally occurring radionuclides. The aim of this study was to understand the cause of gross alpha activity exceeding the screening value of 0.1 Bq L−1 measured in groundwater-derived drinking water in the vicinity of a metamorphic outcrop in Hungary. As groundwater quality is strongly dependent on the properties of groundwater flow systems, environmental tracers (δ2H and δ18O composition, 226Ra, 222Rn, total U activity concentration, and 234U/238U ratio) and hydraulic evaluation were applied to understand groundwater dynamics. The collected groundwater samples had total U activities up to 540 mBq L−1, which translates into an indicative dose below the drinking water parametric value. However, in the presence of dissolved uranium, the δ2H (−52.6–(−83.4)) and δ18O (−7.17–(−11.96)) values led to the conclusion that local flow systems were sampled that...
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Papers by Mikael Hult