Micro-PIXE investigations on some Transylvanian chondritic meteorite fragments and on small Moon soil pieces from the LUNA-16 mission were performed at the Legnaro and Rossendorf proton microprobes. The most exciting finding of the study was the presence of Pt grains in the Moci meteorite. The results are compared to previously published data.

Natural diamond implanted with lithium ions at high energy (E = 2MeV) in axial channeling direction is investigated. Hall measurements show n-type conductivity caused by the lithium implantation. These measurements show two regions in the Arrhenius plot for both resistance and charge carrier concentration. The resistance measurement in the low and high temperature range revealed the activation energies of ERlow = 406meV and ERhigh = 105meV. The slope for the charge carrier concentration shows a more complex behaviour. After annealing, the n-type conductivity caused by implanted lithium disappears.

The combination of microbeam implantation and in-situ micro RBS/channeling analysis in the Rossendorf nuclear microprobe facility enables crystal damage studies with high current densities not achievable in standard ion implantation experiments. Si(100) samples were implanted with 600keV Si+ ions and a fluence of 1×1016cm−2. Using a beam spot of 200μm×200μm current densities from 4 to 120μA/cm2 were obtained. The substrate temperature was varied between RT and 265°C. The implanted regions were subsequently analysed by micro RBS/channeling with a 3MeV He+ beam having a spot size of 50μm×50μm. Crystal damage up to amorphisation was observed in dependence on the substrate temperature. Above a critical temperature TC no amorphisation occurs. TC was determined for each series of samples implanted with the same ion current density j. It was found that the empirical Arrhenius relation j∼exp(−Ea/kTC), known from standard implantation experiments, is also valid at high current densities. The observed Arrhenius law can be derived from a model of epitaxial crystallisation stimulated by defect diffusion.

Five fragments of ancient gold objects belonging to Pietroasa “Cloşca cu Puii de Aur” (“The Golden Brood Hen with Its Chickens”) Romanian hoard were analysed using the micro-PIXE (particle induced X-ray emission) technique. The purpose of the study was to gain some more knowledge regarding the metal provenance by determining the presence of PGE (Platinum Group Elements) and other high-temperature melting point trace elements (Ta, Nb, Cr) at a micrometric scale. Ta and Nb inclusions (micrometric areas of composition different from the surroundings) on three samples and Pd inclusions on one sample were found. The measurements led to some conclusions for the possible gold ore sources of Pietroasa treasury: the South-Ural Mountains, Nubia (Sudan) and/or Anatolian deposits and Roman imperial coins.

The enrichment of fluorine on the surface of Antarctic meteorites is investigated by applying the nuclear reactions F-19(p, alphagamma)O-16 or F-19(p, p'gamma)F-19 with the proton induced gamma emission (PIGE) technique, a class of nuclear reaction analysis (NRA). Results for the Antarctic meteorites ALHA77294, TIL 82409, LEW 86015, ALHA77003, and ALH 83108 are presented. Possible sources of terrestrial F are: volcanic exhalation, tephra layers (volcanic glass), continental soil dust, or sea spray. Material from blue-ice dust-band samples also shows concentrations of F that are significantly higher than the bulk concentrations of meteorites. Finally, a quick investigation for Antarctic meteorites by external PIGE is proposed, leading to a F-contamination index that supplements the qualitative ABC-weathering index.

Several fragments of ancient gold objects coming from an Eneolithic hoard and from Pietroasa ‘Cloşca cu Puii de Aur’ (‘The Golden Brood Hen with Its Chickens’) hoard, unearthed on Romanian territory, and two Romanian native gold nuggets samples were analyzed using micro-PIXE technique. The purpose of the study was to clarify the metal provenance. Trace and minor elements (Cu, Te, Sn, Pb, Ti, Cr, V, Mn, Ta) and platinum group elements (PGE) concentrations were estimated. The presence of inclusions (micrometer size areas of composition different from the surroundings) was investigated. We found Si and Ca inclusions on two Eneolithic samples, and Ta inclusions on two samples from Pietroasa hoard. The measurements suggested an alluvial origin of gold for the Eneolithic samples and give indications for the possible gold ore sources of Pietroasa hoard.

Titanium surfaces were treated by exposing them to a beam of sodium ions. Sodium titanate was shown to be incorporated within the oxidic titanium surface. The ion-implanted surfaces were examined for their reactivity by immersion in a simulated body fluid, which showed the formation of surface-bound hydroxyapatite. The surface was characterized by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and optical and electron microscopy. The surface hydroxyl concentration was determined using the nuclear reaction (1)H((15)N, alpha gamma)(12)C. Surface-related parameters that may affect hydroxyapatite nucleation are discussed in terms of the electrical double layer.

The influence of dwell-time effects on the formation of CoSi2 layers was investigated. The layers were produced on Si(111) and Si(100) by ion beam synthesis using a focused ion beam system. The experiments show that the dwell-time has a strong influence on the formation process of the cobalt disilicide films. In order to obtain high quality films suitable for applications short dwell-times (about 1 μs) are necessary.

The enrichment of F on Antarctic meteorites is the result of their exposure to the atmosphere, and its measurement allows a subdivision of the terrestrial age into a duration of exposure on the ice and the time a meteorite was enclosed by the ice. In many cases, the periods of surface exposure are only small fractions of the terrestrial ages of meteorites collected in Antarctica. The enrichment of F on the surfaces of Antarctic achondrites was investigated by means of nuclear reaction analysis (NRA): scanning proton beams with an energy of 2.7 and 3.4 MeV were used to induce the reactions 19F(p, alpha gamma)16O and 19F(p,p gamma)19F, respectively. Gamma signals proportional to the F content were measured. The following Antarctic achondrites were investigated: Martian meteorite ALH 84001; diogenite ALHA77256; the eucrites ALHA81011 and ALHA78132; and in addition, the H5 chondrite ALHA79025. For ALH 84001, our data indicate a period of exposure on the ice of <500 years. Thus, this specimen was enclosed in the ice >95% of its terrestrial age of 13 000 years.

Recently a 3 MV tandetron accelerator was put into operation at the Research Center Rossendorf. At this accelerator we have installed a new nuclear microprobe. The object forming aperture can be changed continuously from 0 to 150 mu m and in each direction independently. The magnetic quadrupole triplet delivered by Danfysik has an energy mass product of 45 MeV amu. Magnetic coils placed behind it scan the beam over an area up to 1 x 1 mm(2). A manipulator with X-Y-Z-translation, 360 degrees rotation, and tilt enables us together with the adequate detectors to apply ERDA, PIXE, RES, and NRA. A PC based CAMAC system acquires data from four ADCs. Up to four elemental maps with up to 128 x 128 pixels can be displayed on-line. All events are stored together with their coordinates in list mode for further analysis. A general problem for a quantitative analysis is the accuracy of charge measurement. Using the whole target chamber as a Faraday cup which would be the best method is impossible in our installation. A negatively biased electrode in front of the target for suppressing the secondary electrons cannot be used either. Therefore a precise current integrator was developed which can operate with a positive offset voltage of several hundred volts at the input. The principle of this integrator will be described as well as first experiences and comparisons to other charge measuring methods. Furthermore, a beam monitoring system based on this integrator was set up for an easy control of the beam.

SiO(x)N(y) layers in the thickness range from 4 to 20 nm are grown by rapid thermal processing (RTP) using NH3 and N2O as nitridants. I-V measurements, investigation of the time-dependent breakdown, and post-stress C-V display significant distinctions between the layers according to their growth conditions. For the explanation of the electrical behaviour, the compositional structure was examined by means of AES, SIMS, and NRA.

For measuring hydrogen concentrations up to a depth of several tens of micrometers we propose the use of a special sample preparation method — ion beam slope cutting. The principle and the experimental arrangement are described. The depth profiles are obtained by line scans of the nuclear microbeam over the slope planes. The nuclear reactions 1H(15N, α0)12C and 1H(11B, α)2α were investigated and proved suitable for hydrogen analysis with the microbeam detecting the α-particles at backward angles.

The nuclear microprobe at the 5 MV tandem accelerator of the Central Institute for Nuclear Research at Rossendorf is realized by object diaphragms of 50, 70 and 100-mu-m and a magnetic quadrupole triplet. The proton microbeam with a spot size of about 4-mu-m is used for NRA. Depth profiles for oxygen in zirconium alloys and for fluorine in human teeth were measured by scanning the beam linearly over cross sections of the samples using the resonant proton backscattering at 4.5 MeV and the nuclear reaction F-19(p, alpha(0))O-16 at 3 MeV, respectively.

The fluorine concentration of chemically enriched hydroxylapatite (Ca10(PO4)6(OH)2) was measured by means of PIGE using the nuclear reactions F-19(p, p' gamma)F-19 and F-19(p, alpha-gamma)O-16. The experiments were done in-two runs with 1.68 and 2.15 MeV proton incidence. The results determined with inelastic scattering are in good agreement in the two runs. The samples are suitable as new fluorine standards in the ppm region to study the fluorine content in tooth enamel.

For studying deuterium depth profiles in surfaces of JET (Joint European Torus) limiters, a new deuterium profiling method was developed and used. A smooth 10-degrees slope plane on the specimen was produced by ion beam slope cutting using a 10 keV Kr ion beam. To detect deuterium the nuclear reaction H-2(C-12, p)C-13 was used at E(C-12(3+) = 7.5 MeV. The very narrow proton peak could be clearly separated from the background of the spectra. For measuring the lateral and vertical deuterium distribution the C-12 beam of the Rossendorf 5 MV tandem accelerator was focussed to about 6-mu-m and scanned across the specimen. The preliminary results show a deuterium distribution up to a depth of about 5-mu-m in a carbon limiter.

lon-implantation-induced selective etching of dielectric materials is considerably diminished with increasing hydrogen content. Making use of the 1H(15N,αγ)12C resonance reaction, low-temperature PECVD Si oxide and Si nitride layers were observed to contain 12 and 23 at.% H, respectively. For different reagents etch rates were measured regarding the virgin and ion—implanted-He+ Ne+ at 60, 100 keV — PECVD films.

The behaviour is investigated of thin PMMA films during 15N2+ ion bombardment at EN = = 6.50 MeV. Using the 1(15N, αγ)12C and 12C, 16O(d, pγ) reactions the hydrogen, carbon, and oxygen contents of the layers are measured in dependence on the 15N2+ ion fluence. Strong losses of all three elements are observed and a dependence of the film composition on the nitrogen ion fluence. Das Verhalten dünner PMMA-Schichten während des 15N2+-Beschusses mit EN = 6,50 MeV wird untersucht. Mittels der 1H(15N, αγ)12C- und 12C, 16O (d, pγ)-Reaktionen worden die Wasserstoff-, Kohlenstoff- und Sauerstoffgehalte der Schichten in Abhängigkeit von der 15X2+-Fluenz gemessen. Starke Verluste aller drei Elernente werden beobachtet und eine Abhängigkeit der Schichtzusammensetzung von der N-Fluenz wird gefunden.