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For many years, Si1−yGey alloys have been applied in the semiconductor industry due to the ability to adjust the performance of Si-based nanoelectronic devices. Following this alloying approach of group-IV semiconductors, adding tin (Sn) into the alloy appears as the obvious next step, which leads to additional possibilities for tailoring the material properties. Adding Sn enables effective bandgap and strain engineering and can improve the carrier mobilities, which makes Si1−x−yGeySnx alloys promising candidates for future opto- and nanoelectronics applications. The bottom-up approach for epitaxial growth of Si1−x−yGeySnx, e.g., by chemical vapor deposition and molecular beam epitaxy, allows tuning the material properties in the growth direction only; the realization of local material modifications to generate lateral heterostructures with such a bottom-up approach is extremely elaborate, since it would require the use of lithography, etching, and either selective epitaxy or epitaxy and chemical–mechanical polishing, giving rise to interface issues, non-planar substrates, etc. This article shows the possibility of fabricating Si1−x−yGeySnx alloys by Sn ion beam implantation into Si1−yGey layers followed by millisecond-range flash lamp annealing (FLA). The materials are investigated by Rutherford backscattering spectrometry, micro-Raman spectroscopy, x-ray diffraction, and transmission electron microscopy. The fabrication approach was adapted to ultra-thin Si1−yGey layers on silicon-on-insulator substrates. The results show the fabrication of single-crystalline Si1−x−yGeySnx with up to 2.3 at. % incorporated Sn without any indication of Sn segregation after recrystallization via FLA. Finally, we exhibit the possibility of implanting Sn locally in ultra-thin Si1−yGey films by masking unstructured regions on the chip, thus demonstrating the realization of vertical as well as lateral Si1−x−yGeySnx heterostructures by Sn ion implantation and flash lamp annealing. [ABSTRACT FROM AUTHOR]

Abstract: There are numerous applications for the thermoionization ion sources in nuclear physics. One of them is the use of these sources in electromagnetic isotope separators on-line, when radioactive samples are exceptionally small. The paper presents the theoretical study of the ionization processes in the source while it operates as an open ionizer (a tube). A limited review of the ion source characteristics, especially concerning source efficiency, is also given. [Copyright &y& Elsevier]

Abstract: The paper presents experimental results of secondary ion energy distributions obtained for Ti and Si targets bombarded by 20–30keV monoisotope Ar+ ion beam. The influence of the extraction voltages between target and a slit of the electrostatic energy analyzer entrance on the energy distributions of secondary ions was investigated. After optimization of the secondary ion extraction system, the mass spectra of secondary ions were also measured. The investigations were done using recently built experimental system. Experimental data are compared with the computer simulation results obtained using TRQR and SATVAL codes. [Copyright &y& Elsevier]

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]

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]

This paper presents a systematic study of the charge transport behavior of heavily doped n-type Ge layers with As and Sb. A nonequilibrium method ion implantation followed by milliseconds flash lamp annealing is applied to synthesize the n++ Ge layers (Ge:As and Ge:Sb). The resulting materials contain free electrons with a density above 3 × 1019 cm−3 and mobility more than 220 cm2/(V s). Quantum corrections to the conductance in a magnetic field are observed at low temperatures. Weak localization persists up to 30 K in Ge:Sb, while only up to 10 K in Ge:As. Using the Hikami–Larkin–Nagaoka model to fit the magnetoconductance data, we obtain the phase coherence length l ϕ of the hyperdoped Ge samples in the range of 70–163 nm. This study may pave a way to explore possible applications for quantum technologies utilizing As- and Sb-hyperdoped Ge. [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]

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]

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]

Abstract: The electron impact ionization by accelerated thermionic electrons is included into the numerical model of thermoemission ion source. Mean free paths of atoms in the ionizer are comparable with the ionizer size at high working temperatures (3500K). The dependence of the source efficiency on the ionizer temperature and the electron impact ionization cross-section is studied. In the case of substances having a small ionization coefficient (β ≪1) the contribution of the electron impact ionization may be dominant at high temperatures and the predictions based on previous surface ionization model can be changed significantly. [Copyright &y& Elsevier]

The last missing piece of the puzzle for the full functionalization of group IV optoelectronic devices is a direct bandgap semiconductor made by CMOS compatible technology. Here, we report on the fabrication of GeSn alloys with Sn concentrations up to 4.5% using ion implantation followed by millisecond-range explosive solid phase epitaxy. The n-type single crystalline GeSn alloys are realized by co-implantation of Sn and P into Ge. Both the activation of P and the formation of GeSn are performed during a single-step flash lamp annealing for 3 ms. The bandgap engineering in GeSn as a function of the doping level and Sn concentration is theoretically predicted by density functional theory and experimentally verified using ellipsometric spectroscopy. We demonstrate that both the diffusion and the segregation of Sn and P atoms in Ge are fully suppressed by millisecond-range nonequilibrium thermal processing. [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]

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]

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]

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]

Three variants of the design of ion sources are described: (1) with a hollow cathode and an anode-evaporator system in the rear part of the source, (2) with a cylindrical anode, and (3) with a hollow cathode and an anode in the front part. It is shown that these sources are most suitable for obtaining ion beams of solid-state elements and provide ion currents of ∼70-100 μA (for Al, Bi, As, Sb), 25 μA (Eu), and 15-30 μA (Fe, V, Cr, and doubly charged and molecular ions). Such sources are characterized by a relatively long operation time (tens of hours) and a low energy consumption level (300-400 W). The operational principle of ion sources is described with consideration for the differences in their designs. The experimental results are presented: the dependences of the ion currents on the discharge current, cathode current, and induction of the magnetic field of the source's electromagnet, as well as the results of the computer simulations that are based on a numerical model of the ionization of atoms in the source. [ABSTRACT FROM AUTHOR]

A new numerical Monte Carlo method based model of a hot cavity surface ionization ion source is presented in this paper. The model, intended to support the studies on ionization phenomena in a widely used class of ion sources, takes into account geometry of the ion source and extraction system, ionizer temperature and other features. The results of ion source efficiency calculations for various configurations of the extraction field are reviewed. The dominant role of the ionizer region near the extraction opening is described. Simulated dependences of ionization efficiency on the working parameters like ionizer length and temperature, ionization potential of the substance, and extraction voltage are discussed. A good agreement of the experimental data (e.g., influence of ionizer temperature, current-voltage curve) and the predictions of the model is found. It is also shown that the contribution to the ionization yield from impact of thermionic electrons accelerated by the extraction field may be significant, especially for the substances of small surface ionization coefficient. The simulation results are compared to the predictions of different theoretical models of the ion source-the obtained simulation data are in accordance both with a well-known Kirchner formula and the so called spherical ionizer model. [ABSTRACT FROM AUTHOR]

Abstract: A novel construction of a hollow cathode ion source equipped with an internal crucible is presented. The crucible (also known as the evaporator) containing the feeding substance is heated to a high temperature by a hot cathode filament and an arc discharge to enable production of ions from solids. Another crucial feature of the ion source is the proximity of the arc discharge and an extraction opening that enables the production of an intense ion beam even for very low discharge currents (up to 1.2A). The ion source provides currents of 80μA (In+), 70μA (Bi+), 60μA (Mn+), 50μA (As+ and Al+) and 35μA (Sb+) for a typical extraction voltage of 25kV. The ion source is also able to produce beams of molecular and doubly charged ions (e.g. Sb2 +, As2 +, Bi2+ and As2+). The time between maintenance breaks is 20–40h (depending on the feeding substance) making it possible to perform high fluence implantations (1017 ions per cm2) with ions of solids within a single work cycle. The detailed description of the ion source as well as its principle of operation is given. Experimental characteristics i.e. dependencies of extracted beam currents and anode voltage on anode and cathode currents are presented and discussed. The influence of magnetic field flux density on ion source''s performance is also shown. A model of ionization in the ion source based on Monte Carlo method is described—some simulation results are shown in order to enrich the discussion. [Copyright &y& Elsevier]

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]

Abstract: The experimental measurements and computer simulation results of the intensity of the Ar+ ion current emitted from the hollow cathode ion source as a function of extraction voltage are presented in the paper. The computer simulations of the phenomena inside the ion chamber and ion beam formation were done using modified version of the TRQR code based on particle-in-cell (PiC) method. The agreement between experiment and calculated results is quite good. [Copyright &y& Elsevier]

The paper describes a plasma ion source for ionization of low-volatile elements of a high ionization potential. The source is characterized by a high operation temperature and relatively effective ionization. Plasma in a closed volume of the hollow cathode is produced by thermoemission electrons and ionized atoms dosed to the source or diffused from the walls of heated cathode. The construction of the source makes its operation possible in electromagnetic isotope separators on-line, e.g. on a beam of highly energetic protons of YASNAPP facility (Nucl. Instrum. Methods B70 (1992) 62). [Copyright &y& Elsevier]

Abstract: When amorphous SiO2 films are bombarded with energetic ions, various types of defects are created as a consequence of ion-solid interaction (peroxy radicals POR, oxygen deficient centres (ODC), non-bridging oxygen hole centres (NBOHC), E′ centres, etc.). The intensity of the electroluminescence (EL) from oxygen deficiency centres at 2.7eV, non-bridging oxygen hole centres at 1.9eV and defect centres with emission at 2.07eV can be easily modified by the ion implantation of the different elements (H, N, O) into the completely processed MOSLED structure. Nitrogen implanted into the SiO2:Gd layer reduces the concentration of the ODC and NBOHC while the doping of the oxygen increases the EL intensity observed from POR defect and NBOHC. Moreover, after oxygen or hydrogen implantation into the SiO2:Ge structure fourfold or fifth fold increase of the germanium related EL intensity was observed. [Copyright &y& Elsevier]

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]

On the surfaces of crystalline semi-insulating GaAs (100), irradiated with noble gas Ar + and Xe + layers of native oxides are formed in the air under ordinary conditions. The surface atomic density of elements and chemical composition of those near the surface layers were studied by means of Rutherford backscattering spectroscopy, nuclear reaction and X-ray photoelectron spectroscopy. In these layers the dependences of the surface atomic density of oxygen and chemical compositions as a function of doses in the region from 1 × 10 13 to 1 × 10 16 ions/cm 2 were determined. It was found that the former value depends on the kind of implanted ions and the relationships of Ga 2 O 3 , As 2 O 3 and As 2 O 5 in the native oxide layers changed with the increase of the fluence. Moreover, the concentrations of Ga 2 O 3 increased and those of As 2 O 3 and As 2 O 5 decreased with the increasing irradiation fluence. [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]

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]

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]

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]

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]

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]

Abstract: A novel construction of an ion source with an evaporator placed inside a plasma chamber is presented. The crucible is heated to high temperatures directly by arc discharge, which makes the ion source suitable for substances with high melting points. The compact ion source enables production of intense ion beams for wide spectrum of solid elements with typical separated beam currents of ∼100–150μA for Al+, Mn+, As+ (which corresponds to emission current densities of 15–25mA/cm2) for the extraction voltage of 25kV. The ion source works for approximately 50–70h at 100% duty cycle, which enables high ion dose implantation. The typical power consumption of the ion source is 350–400W. The paper presents detailed experimental data (e.g. dependences of ion currents and anode voltages on discharge and filament currents and magnetic flux densities) for Cr, Fe, Al, As, Mn and In. The discussion is supported by results of Monte Carlo method based numerical simulation of ionisation in the ion source. [Copyright &y& Elsevier]

Abstract: Semi-insulating (100) GaAs single crystalline substrates have been doubly Al+-implanted using ion beams of the 250keV energy and the fluence F =3.5×1016 cm−2, and 100keV with F =9.6×1015 cm−2 at six target temperatures ranging from 250 to 500°C. The radiation damage introduced by such “hot implantation” was subsequently investigated by Rutherford Backscattering Spectrometry with Channeling (RBS-C) and Variable Angle Spectroscopic Ellipsometry (VASE) techniques. Using these experimental methods we determined a degree of lattice disorder. With the increasing implantation temperature the degree of disorder substantially decreases. No evidence of full amorphization of the implanted GaAs layers has been found in the present studies. The results of non-destructive ellipsometric characterization are in good agreement with the RBS-C investigations. [Copyright &y& Elsevier]

InAs quantum dots (QDs) were successfully formed in single-crystalline Si by sequential ion implantation and subsequent milliseconds range flash lamp annealing (FLA). Samples were characterized by μ-Raman spectroscopy, Rutherford Backscattering Spectrometry (RBS) high-resolution transmission electron microscopy (HRTEM) and low temperature photoluminescence (PL). The Raman spectrum shows two peaks at 215 and 235 cm corresponding to the transverse optical (TO) and longitudinal optical (LO) InAs phonon modes, respectively. The PL band at around 1.3 μm originates from the InAs QDs with an average diameter 7.5±0.5 nm and corresponds to the increased band gap energy due to the strong quantum confinement size effect. The FLA of 20 ms is sufficient for InAs QDs formation. It also prevents the out-diffusion of implanted elements. Moreover, the silicon layer amorphized during ion implantation is recrystallized by solid-phase epitaxial regrowth during FLA. [ABSTRACT FROM AUTHOR]

The best method for the impurity doping to the host material is the ion implantation. Due to high melting point of the rare earth standard metal ion sources are useless. One of the solution is to use chemical compounds of rare earths characterized by low melting point. In this paper we describe the novel design of the ion source suitable for refractory metal (e.g., rare earths) ion implantation. The dependencies of Eu+ current on cathode and arc currents as well as on hydrogen flow are presented. Europium (III) chloride as the source of the europium atoms was used. Europium ions were produced during collisions of evaporated and decomposed EuCl3 molecules with fast electrons. The typical current of the europium ion beam extracted from the ion source was 25 μA for the extraction voltage of 25 kV. The ion source works without maintenance breaks for approximately 50 h, which enables high dose implantation. The presented ion source needs neither advanced high power supplies nor high vacuum regime. [ABSTRACT FROM AUTHOR]

A description of an ion source for solid elements is given. The solid elements from which ions are to be obtained, were mechanically sputtered by means of a rotating stone-wheel and were dosed in the form of powder into an arc discharge chamber of the ion source and partly to the hot anode, from where in the form of vapour they went to the discharge chamber. [Copyright &y& Elsevier]