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Thermal desorption spectrometry measurements of Kr implanted with energies 100 keV and 150 keV (fluence 2 × 1016 cm-2) into the Ge sample are considered. A sudden release of Kr is observed in the temperature range of 800-840 K. The very narrow peaks in the thermal desorption spectrometry spectra (width of several K) come most probably from the release of gas trapped in pressurized bubbles. Analysis of peak shifts with increasing heating rate enabled the estimation of the adsorption activation energy values of 2.5 eV and 2.3 eV for the implantation energies 100 keV and 150 keV, respectively. These values are comparable to those obtained for Ar implanted into the Ge samples and for Kr implanted into the Si samples. [ABSTRACT FROM AUTHOR]

Very thin (3 μm in thickness) polyethylene terephthalate polymer foils were implanted with 150 keV Li+ with fluences in the range from 1×1014 cm-2 up to 2×1016 cm-2. Modification of the irradiated polymer microstructure was studied with the Fourier transform infrared spectroscopy and Raman spectroscopy. Breaking of a variety of chemical bonds followed by the formation of carbon clusters made of sp2 C was proved. The dominance of the rings in the carbonized, graphite-like subsurface layer is demonstrated based on the fact that the G band prevails in the Raman spectra for larger Li+ fluences. The rise of the absorbance within 200-800 nm is observed. Tauc's plots analysis enables the estimation of optical bandgap values that decrease from 3.95 eV (pristine polyethylene terephthalate) down to 1.4 eV (fluence of 2 × 1016 cm-2). This change is not as dramatic as in the case of heavier projectiles like K+ or Na+. Reduction of surface resistivity by more than 2 orders of magnitude is observed in the case of the sample irradiated with the fluence 1 × 1016 cm-2, and this effect is much smaller than that induced by the heavier projectile bombardment with the same fluence. [ABSTRACT FROM AUTHOR]

Using the method of reactive magnetron sputtering, nanostructured TiAlN coatings were formed on the substrates of AISI 304 stainless steel. The formed TiAlN coatings were irradiated with argon ions Ar+ with an energy of 200 keV in the fluence range from 2:5 × 1016 ions/cm² to 2 × 1017 ions/cm² at a temperature of 480°C. The elemental composition and structural-phase state of virgin and irradiated coatings were investigated by methods of energy-dispersive X-ray spectroscopy, scanning electron microscopy as well as X-ray phase analysis. The mechanical properties of the obtained structures were studied by nanoindentation using the Oliver and Pharr method; hardness and Young's modulus were measured. The indicators of the impact strength, as the H=E* ratio, as well as the resistance to plastic deformation, as the H³=E*2 ratio, of the coatings under study were calculated. It was found that the nanostructured TiAlN coatings retain their structure up to the irradiation fluence of 2×1017 ions/cm², at which the beginning of phase segregation of solid solution (Ti, Al)N as the main phase of the coating as well as blistering is observed. The nonlinear nature of changes in the hardness H, Young's modulus E, impact strength H=E*, and resistance to plastic deformation H3=E*2 on the irradiation fluence was found. [ABSTRACT FROM AUTHOR]

The thermal desorption spectrometry (TDS) measurements of He implanted with the energies 80 keV and 100 keV into Ge was considered. The release of the noble gas took place at temperature range 600-950 K. The TDS spectra had a form of a very wide peak consisting of two parts which means that one deals with two states of He into Ge. No surface blistering or formation of craters was observed after the annealing of the samples implanted with the fluence 1 × 1016 cm-2. the critical fluence needed for bubble formation in Ge is higher than for Si. The analysis of the peak shift with the heating ramp rate allows estimation of desorption activation energies. They are close to 0.8 eV for both peaks (100 keV) while the energy for the second peak in the case of E = 80 keV was more than twice higher. [ABSTRACT FROM AUTHOR]

Microhardness results and the occurrence of radiation defects at a greater depth than the predicted implanted ion range indicate the presence of the so-called long-range effect. An attempt is made to determine the thickness of a layer with modified tribological properties by measuring friction and wear factors. Tribological tests are performed on the pin-on-disc stand. The real thickness of a layer with implantation-modified tribological properties can be determined via tribological testing by measuring the wear trace depth when the friction factor and/or wear of the implanted sample is close to that characteristic of an unimplanted sample. The predicted range of the implanted ions is estimated by the SRIM and SATVAL programs. The presence of the long-range effect is confirmed for the steel grades AISI 316L, H11, Raex 400, Hardox 450 as well as for the Stellite 6 and Ti6Al4V alloys. The modified layer thickness determined by tribological testing is considerably greater (4:7 % 16:7 times) than the initial range of the implanted nitrogen ions. The observed depth of changes in the tribological properties of the surface layer (due to the long-range effect) is consistent with the nanohardness results obtained for the steel grades AISI 316 and H11. An analysis of the content of elements on the sample surface as well as in its wear trace and wear products is performed by X-ray spectroscopy (EDS and WDXS). The results demonstrate that one of the causes of the long-range effect is the diffusion of nitrogen and carbon atoms in the friction zone during the tribological test. [ABSTRACT FROM AUTHOR]

Very thin (3 µm) polyethylene terephthalate (PET) foils were irradiated with 150 keV Na+ ions with the fluences in the range from 1 × 1014 cm-2 up to 1 × 1016 cm-2. Modification of chemical structure of the implanted polymer was studied with the Fourier transform infrared and Raman spectroscopies. Destruction of numerous chemical bonds as well as formation of carbon clusters made of sp2 hybridised C atoms and conducting cluster networks were demonstrated. The increasing presence of chain structures in the graphite-like carbonised layer is pointed out as the G band shift and decrease of D band could be seen as irradiation fluence rises. The large increase of the modified sample absorbance with the implantation fluence in the UV-VIS region was observed. The decrease of optical band-gap energy from 3.95 eV for the pristine sample down to 0.7 eV for the most heavily treated sample was estimated using the Tauc plot. Reduction of bulk resistivity by more than 8 orders of magnitude is shown in the case of the sample implanted with the fluence 1 × 1016 cm-2. The sheet resistivity of the sample was also reduced by 5 orders of magnitude. The effect was observed on both sides of the sample, probably as the result of chemical transformations due to local increase of the polymer foil temperature. The moderate increase (15-200%) of the dielectric constant is observed in the frequency range up to 1 MHz and the change rises with the implantation fluence. [ABSTRACT FROM AUTHOR]

A new method of refractory metal (like Mo and Ta) ion beam production using the arc discharge ion source and CCl2F2 (dichlorodifluoromethane) used as a feeding gas supported into the discharge chamber is presented. It is based on etching of the refractory metal parts (e.g. anode or a dedicated tube) Cl and F containing plasma. The results of measurements of the dependences of ion currents on the working parameters like discharge and filament currents as well as on the magnetic field flux density of an external electromagnet coil are shown and discussed. The separated Mo+ and Ta+ beam currents of approximately 22 µA and 2 µA, respectively, were obtained. [ABSTRACT FROM AUTHOR]

Thin (3 µm) polyethylene terephthalate (PET) foils were irradiated with 135 keV He+, Ne+ and Ar+ ions with the fluences up to 5×10-5 cm-2. Changes of chemical structure of the polymer were studied with the Fourier transform infrared and Raman spectroscopy - breaking of numerous chemical bonds, polymer chain cross-linking as well as formation of sp² hybridised carbon clusters and cluster networks were demonstrated. The increase of the implanted sample absorbance with the implantation fluence in the UV-VIS spectra as well as the decrease of optical band-gap energy (2.75 and 2.0 eV for He and Ne, respectively, at 5×1015 cm-2) are observed. Decrease of bulk resistance of heavily treated samples by -5 orders of magnitude is determined. Measurements of the sheet resistance confirm that the sample becomes conducting also on the reverse (unimplanted) side of the foil. Both of these effects depend on the impinging ion mass - they are the strongest for Ar. The increase of both ac conductance and dielectric constant is observed in the frequency range up to 2 MHz and these changes rise with the impinging ion mass. [ABSTRACT FROM AUTHOR]

The thermal desorption spectrometry studies of krypton implanted Si samples are presented. Implantations (with the fluence 2×10-6 cm-²) were done with the energies 100, 150, and 200 keV. Additionally, a 200 keV and 100 keV Kr+G double implantation was performed. A sudden Kr release was observed in the ≈1100-1400 K range, most probably coming from the gas bubbles in cavities. The desorption activation energy varies from 2.5 eV (100 keV) to 0.8 (200 keV). The peak splitting suggests existence of two kinds of cavities trapping the implanted noble gas. Two Kr releases are observed for the 200 and 100 keV double-implanted samples. The peak shift of the release corresponding to 100 keV implantation could be a result of both introduced disorder and higher effective Kr concentration. The desorption activation energy is risen to ≈3.2 eV for both releases. [ABSTRACT FROM AUTHOR]

Two different designs of the internal evaporator in an arc discharge ion source are presented, suitable either for volatile, or high-melting point substances. A matter of the evaporator size and placement in order to obtain its appropriate temperature and, therefore, a stable and intense ion beam, is considered. Basic ion source characteristics, i.e. the dependences of ion current and discharge voltage on the discharge and filament currents as well as on the external magnetic field flux density are shown and discussed in order to find optimal working conditions. The results of measurements for both volatile (P, Zn, Se, S) and non-volatile (Pd) are presented, showing the applicability of the design for ion implantation purposes. [ABSTRACT FROM AUTHOR]

The thermal desorption spectroscopy measurements of He implanted silicon samples are reported. The He implantation energy was 90 keV (at 45° tilt) while the fluence was 1016 cm-2. Additionally, the influence of Si pre-implantation (fluences in the range 1014-1016 cm, E = 260 keV) was under investigation. The He releases from both interstitials/vacancies (β peak) and cavities (α peak or rather band consisting probably of at least two peaks) were observed. The α peak disappears for the pre-implantation fluences larger than 1015 cm-2, while β peak becomes broader and shifts toward higher temperatures. The thermal desorption spectra were collected using heating ramp rates in the range 0.3-0.7 K/s. Desorption activation energy of the β peak for different pre-implantation fluences was found using the Redhead analysis of the β peak shift. It varies from 0.97 eV for the sample that was not pre-implanted up to 1.3 eV for the sample pre-implanted with the fluence 1016 cm-2. [ABSTRACT FROM AUTHOR]

The effect of nitrogen ion implantation on Stellite 6 cobalt alloy was investigated. In this research, cobalt alloy was implanted with 65 keV nitrogen ions at the fluence of (1÷10)×1016 N+/cm². The distribution of implanted nitrogen ions and vacancies produced by them was calculated using the SRIM program. The surface morphology was examined and the elemental analysis was performed using scanning electron microscopy, energy dispersive X-ray spectroscopy and grazing incidence X-ray diffraction. The wear tests were conducted with the use of the pin-on-disc method. The results demonstrate that implantation with nitrogen ions significantly reduces the friction factor and wear. The friction coefficient of the implanted sample at the fluence of 1×1017 N+/cm² increased to the values characteristic of an unimplanted sample after 5000 measurement cycles. The depth of the worn trace was about 2.0 µm. This implies that the thickness of the layer modified by the implantation process is ≈2.0 µm and exceeds the initial range of the implanted ions by an order of magnitude. This is referred to as a long-range implantation effect. The investigations have shown that the long-range effect is caused by movement of not only implanted nitrogen atoms but also carbon dopant atoms towards the friction zone. Diffusion of carbon atoms has been documented here for the first time. Furthermore, the increased content of oxygen atoms on the track bottom indicates a dominant oxidative wear of the Stellite samples after nitrogen implantation with the energy 65 keV and the fluences of 5×1016 and 1017 N+/cm². [ABSTRACT FROM AUTHOR]

Thermal desorption spectrometry measurements were performed for Ar implanted Si samples. Implantation energy E\ varied in the range 85-175 keV. The release of implanted Ar in two steps was observed in the temperature range 930-1300 K: the relatively narrow peak at lower temperature (≈ 930 K for implantation fluence 5 × 1016 cm-2) is due to the release of Ar from the agglomerations (bubbles) while the broader peak observed for higher temperatures (≈ 950 K for implantation fluence 5 × 1016 cm2) comes from Ar atoms diffusing out of the sample. Inverse order of peaks is observed compared to the results for lower energy implantations (< 50 keV). Analyzing the thermal desorption spectra collected for different heating ramp rates enabled estimation of the desorption activation energy (2 eV for Ei = 85 keV and 1.7 eV for Ei = 115 keV). [ABSTRACT FROM AUTHOR]

A new method of Mo+ ion beam production is presented in the paper. The method bases on the chemical sputtering/etching of the molybdenum parts (e.g. anode) of the arc discharge ion source by the chloride containing plasma. A mixture of CCl4 (or CHCI3) vapor and air was used as the feeding substance. The separated Mo+ beam current of approximately 18 μA was achieved. The measurements of the ion current dependences on the discharge and filament currents as well as on the magnetic field flux density from the electromagnet surrounding the discharge chamber were performed in order to find the optimal working parameters of the ion source. [ABSTRACT FROM AUTHOR]

Copper indium gallium diselenide (CIGS) becomes more significant for solar cell applications as an alternative to silicon. The quality of the layer has a critical impact on the final efficiency of the solar cell. An influence of the post-deposition millisecond range flash lamp annealing on the optical and microstructural properties of the CIGS films was investigated. Based on the Raman and photoluminescence spectroscopy, it is shown that flash lamp annealing reduces the defect concentration and leads to an increase of the photoluminescence intensity by a factor of six compared to the nonannealed sample. Moreover, after flash lamp annealing the degradation of the photoluminescence is significantly suppressed and the absolute absorption in the wavelength range of 200-1200 nm increases by 25%. [ABSTRACT FROM AUTHOR]

Difierent semiconductor nanocrystals synthesized in dielectrics on silicon are very interesting for applications in non-volatile memories and photovoltaics. In this paper we present an overview of microstructural and opto-electronic properties of different III-V quantum dots embedded in SiO2 and Si3N4 made by sequential ion implantation and millisecond range fiash lamp annealing. It is shown that within 20 ms post-implantation annealing high quality crystalline III-V quantum dots can be formed in different matrices. Formation of crystalline III-V quantum dots was confirmed by cross-section transmission electron microscopy, photoluminescence and μ-Raman spectroscopy. Flash lamp annealing is essentially a single-fiash-single-wafer technique whose main attributes are the ease and control of processing over large wafer batches. [ABSTRACT FROM AUTHOR]

The paper describes the production of doubly charged ions from solids and gases using a hollow cathode ion source with an internal evaporator heated by a spiral cathode filament and arc discharge. The obtained currents were 15 µA for Bi2+, 10 µA for As2+ and Al2+, 8 µA for Kr2+ and Xe2+, 5 µA for In2+ and Ge2+, enabling moderate dose implantations (≈ 1015 cm-3) with doubly charged ions. Characteristics of the ion source are presented and discussed in order to choose the optimal working parameters. A brief presentation of numerical model of doubly and singly charged ions in the ion source is given. The calculated results (dependences of ion current on the anode voltage) are in good agreement with the experimental data. [ABSTRACT FROM AUTHOR]

Remarkable thermo-mechanical and electrical properties of silicon carbide (SiC) make this material very attractive for high-temperature, high-power, and high-frequency applications. Because of very low values of diffusion coefficient of most impurities in SiC, ion implantation is the best method to selectively introduce dopants over well-defined depths in SiC. Aluminium is commonly used for creating p-type regions in SiC. However, post-implantation radiation damage, which strongly deteriorates required electric properties of the implanted layers, is difficult to anneal even at high temperatures because of remaining residual damage. Therefore implantation at elevated target temperatures (hot implantation) is nowadays an accepted method to decrease the level of the residual radiation damage by avoiding ion beam-induced amorphization. The main objective of this study is to compare the results of the Rutherford backscattering spectroscopy with channeling and micro-Raman spectroscopy investigations of room temperature and 500°C Al+ ion implantation-induced damage in 6H-SiC and its removal by high temperature (up to 1600°C) thermal annealing. [ABSTRACT FROM AUTHOR]

We have studied the influence of ion implantation and post-implantation annealing regimes on the structural and optical properties of silicon matrix with ion-beam synthesized InAs nanocrystals. (100) Si wafers were implanted at 25 and 500°C, subsequently with high fluences of As and In ions. After implantation the samples were processed by furnace and rapid thermal annealing at 900, 950 and 1050°C. A part of the samples implanted at 25°C was additionally exposed to H2+ ions (100 keV, 1.2 × 1016 cm-2 in terms of atomic hydrogen). This procedure was performed to obtain an internal getter. In order to characterize the implanted samples transmission electron microscopy and low-temperature photoluminescence techniques were employed. It was demonstrated that by introducing getter, varying the ion implantation temperature, ion fluences and post-implantation annealing duration, and temperature it is possible to form: InAs nanocrystals in the range of sizes of 2-80 nm and create various concentration and distribution of different types of secondary defects. The last ones cause in turn the appearance in photoluminescence spectra dislocation-related D1, D2 and D4 lines at 0.807, 0.870 and 0.997 eV, respectively. [ABSTRACT FROM AUTHOR]

A new construction of a hollow cathode ion source equipped with an internal evaporator heated by a spiral cathode filament and arc discharge is presented. The source is especially suitable for production of ions from solids. The proximity of arc discharge region and extraction opening enables production of intense ion beams even for very low discharge current (Ia = 1.2 A). The currents of 50 μA (Al+) and 70 μA (Bi+) were obtained using the extraction voltage of 25 kV. The source is able to work for several tens of hours without maintenance breaks, giving possibility of high dose implantations. The paper presents the detailed description of the ion source as well as its experimental characteristics like dependences of extracted currents and anode voltage on anode and cathode currents. [ABSTRACT FROM AUTHOR]

The semi-isolating GaAs (100) samples irradiated with fluence 3 × 1015 ions/cm² of In+ ions were characterized by using the methods: Rutherford backscattering spectroscopy, nuclear reaction analysis and ellipsometric spectroscopy. The values of the thicknesses layers enriched with oxygen and the implanted were determined by the methods of nuclear reaction analysis and Rutherford backscattering spectroscopy. Multilayer models were applied for determination of the optical constants (refraction and extinctions coefficients) of investigated samples. The thickness of native oxide covering the surface of implanted GaAs and refraction coefficients were increased after implantation with indium. The spectrum of extinction indexes as a function of light wavelength has two bands near the light wavelengths 400 nm and 480 nm. The observed effects can be interpreted as formation of local oxides of In and InAs precipitates or ternary alloys in enriched with oxygen layers at the surfaces of implanted GaAs. [ABSTRACT FROM AUTHOR]

A new method of refractory metal (like Mo and Ta) ion beam production using the arc discharge ion source and CCl2F2 (dichlorodifluoromethane) used as a feeding gas supported into the discharge chamber is presented. It is based on etching of the refractory metal parts (e.g. anode or a dedicated tube) Cl and F containing plasma. The results of measurements of the dependences of ion currents on the working parameters like discharge and filament currents as well as on the magnetic field flux density of an external electromagnet coil are shown and discussed. The separated Mo+ and Ta+ beam currents of approximately 22 µA and 2 µA, respectively, were obtained. [ABSTRACT FROM AUTHOR]