Effect Of Ion Implantation Research Articles

The effect of ion implantation and annealing temperatures on the migration behavior of ruthenium in glassy carbon

Nuclear waste storage materials are inevitable in nuclear industry for preventing the release of radioactive waste products. Glassy carbon has been considered being beneficial to be used in the dry cask needed for nuclear waste storage. Thus, we studied the migration of ruthenium implanted in glassy carbon upon annealing. Our investigations show that ruthenium implantation caused defects in the glassy carbon structure, with more defects observed in the room temperature as-implanted samples compared to those implanted at 200 °C. Annealing the as-implanted samples from 500 to 800 °C showed no significant change in the ruthenium depth profiles, indicating the non-diffusivity of ruthenium in glassy carbon at these temperatures. However, annealing at higher temperatures (from 900 and 1300 °C) resulted in an increase in the maximum depth profile peaks, accompanied by a shift towards the surface, and a decrease in the full-width at half-maximum. These changes indicate the aggregation of ruthenium atoms in the near-surface region. Additionally, more ruthenium aggregation was observed in room temperature implanted samples compared to those implanted at 200 °C. This difference is attributed to the higher concentration of defects in room temperature implanted samples, which promotes ruthenium aggregation. Moreover, the migration and aggregation of ruthenium in the near-surface region contributed to an increase in the surface roughness of the glassy carbon.

Optical and structural transformations in polyethylene terephthalate (PET) films subjected to Ag[formula omitted]-ion implantation and subsequent Au[formula omitted]-ion irradiation

We report on the dual effects of ion implantation and swift heavy ion on the optical and structural characteristics of polyethylene terephthalate (PET) films using UV–Vis spectrophotometry, FTIR and X-ray diffraction measurements. Samples were first implanted with 150 keV Ag+-ions at different fluences of 1 ×1016, 5 ×1016, and 1 ×1017 ions/cm2, and thereafter irradiated with 30 MeV Au7+-ions at different fluences, while analysing elemental depth profile in situ on the Time of Flight Heavy Ions Elastic Recoil Detection (ToF-Hi-ERDA) instrument. The elemental depth profile measurements showed considerable atomic depletion of hydrogen from 36% down to below 6% and oxygen from 18% to about 5%. The proportion of carbon increased from 45% to over 87%. The optical bandgap decreased with increasing ion implantation fluence and reduced even further on irradiation with 30 MeV 197Au7+-ions. The most notable outcome of the implantation was the onset of the precipitation of gold nanoparticles (Au-NPs) in the PET matrix, marked by Localised Surface Plasmon Resonance effects, coincided with a relatively significant drop in the bandgap energy. This latter effect could only be best explained as the result of these Au-NPs in the PET. This suggests that optical bandgap tuning in polymer films, usually achievable through high fluence implantation at low energy (i.e., keV), could also be realized through low fluence irradiation with MeV energy ions. It is surmised that, for the noble metals, NP-induced bandgap modification in PET precludes the need for high fluence to achieve the same. This has the obvious advantage of bandgap alterations at much lower structural damage to the target polymer. As reported by FTIR results, one can observe structural changes with the formation of new chemical bonds on thin films. X-ray diffraction results exhibited one prominent peak corresponding to the (100) plane, which varies in intensity with increased implantation fluence, suggesting a change in the crystallinity of the PET. The decrease in (100) peak or crystallinity was well connected with the presence and decrease of 847, 970, and 1471 cm−1 peaks, which were assigned to the ethylene glycol molecular groups.

Effects of Cu ion implantation on the microstructure, dielectric and impedance properties of SrTiO3 ceramics prepared by reduction-reoxidation method

SrTiO3 ceramic samples were successfully prepared using an innovative approach that combined ion implantation technique with the reductive-reoxidation sintering method. SrTiO3 ceramics were reductively sintered in N2 and H2 atmosphere, and Cu ion implanted, followed by thermal oxidation treatment in air. Experimental results demonstrate a notable reduction in dielectric loss while achieving a colossal permittivity (ε = 41,444 at 1 kHz, tanδ = 0.054 at 1 kHz). The phase structure, micromorphology, element valence state, dielectric properties and AC impedance spectrum characteristics of SrTiO3 ceramic materials were studied, and the mechanism of dielectric properties was explained using the Internal Barrier Layer Capacitor (IBLC) effects. Research results show that Cu ion implantation, oxygen vacancies at ceramic grain boundaries, and oxygen adsorption during reoxidation thermal treatment play a key role in reducing the dielectric loss of the material.

TEM Investigation on High Dose Al Implanted 4H-SiC Epitaxial Layer

Within this work, the effect of high dose Al ion implantation on 4H-SiC epitaxial layer is displayed. Through TEM investigation it is demonstrated that the implanted surface is suitable as seed for subsequent epitaxial regrowth generating a crystal free of extended defects. In order to assess the defects within the projected range of the ion implanted area, High Angle Annular Dark Field STEM (HAADF-STEM) analyses were performed demonstrating the atomic arrangement of the lattice in correspondence of the dislocation loop and the deviation of the crystallographic planes of 4H-SiC, driven by stress relaxation, that determine the staircase configuration of the implant pattern. Further emphasis is given to the detailed analysis of the precipitates atomic structure, whose preferential localization is ascertained. Using Energy-Dispersive X-ray spectroscopy (EDS) analysis, the precipitate is finally established as Al crystal with an FCC structure.

The effect of transition metal ion implantation on the structural and optical properties of few-layered borophene

Borophene, a monometallic two-dimensional layered material has gained significant attention due to its exceptional electrical and optical properties. Despite this, borophene layers tend to restack; retards ionic conductivity, imperative for practical applications. Thus, by introducing large-sized dopants into borophene nanosheets using an ion implantation technique has been acknowledged. Accordingly, herein, structural and electronic engineering of borophene has been done with implantation of copper (Cu) ions at various fluence rates (5 × 1012, 5 × 1013, 5 × 1014 and 5 × 1015 ions-cm−2 respectively) using 1μA current at a low energy of 80 keV. The Cu insertion between borophene interlayers prevents self-restacking; providing surfacial active sites with tunable work function and decreased band gap of pristine borophene, thereby increasing charge transport ability. Further, the structural properties of implanted borophene were characterized through Raman spectroscopy, FT-IR spectroscopy and optical properties using UV–Vis and photoluminescence studies. Also, I-V measurements were conducted to study the electrical properties. Hence, ion implantation helps in significantly enhance the electrical conductivity and transportation properties of borophene.

Nano-cutting mechanism of ion implantation-modified SiC: reducing subsurface damage expansion and abrasive wear

This study utilized ion implantation to modify the material properties of silicon carbide (SiC) to mitigate subsurface damage during SiC machining. The paper analyzed the mechanism of hydrogen ion implantation on the machining performance of SiC at the atomic scale. A molecular dynamics model of nanoscale cutting of an ion-implanted SiC workpiece using a non-rigid regular tetrakaidecahedral diamond abrasive grain was established. The study investigated the effects of ion implantation on crystal structure phase transformation, dislocation nucleation, and defect structure evolution. Results showed ion implantation modification decreased the extension depth of amorphous structures in the subsurface layer, thereby enhancing the surface and subsurface integrity of the SiC workpiece. Additionally, dislocation extension length and volume within the lattice structure were lower in the ion-implanted workpiece compared to non-implanted ones. Phase transformation, compressive pressure, and cutting stress of the lattice in the shear region per unit volume were lower in the ion-implanted workpiece than the non-implanted one. Taking the diamond abrasive grain as the research subject, the mechanism of grain wear under ion implantation was explored. Grain expansion, compression, and atomic volumetric strain wear rate were higher in the non-implanted workpiece versus implanted ones. Under shear extrusion of the SiC workpiece, dangling bonds of atoms in the diamond grain were unstable, resulting in graphitization of the diamond structure at elevated temperatures. This study established a solid theoretical and practical foundation for realizing non-destructive machining at the atomic scale, encompassing both theoretical principles and practical applications.

Effects of ion implantation with arsenic and boron in germanium-tin layers

Ion implantation is widely used in the complementary metal–oxide–semiconductor process, which stimulates to study its role for doping control in rapidly emerging group IV Ge1−xSnx materials. We tested the impact of As and B implantation and of subsequent rapid thermal annealing (RTA) on the damage formation and healing of the Ge1−xSnx lattice. Ion implantation was done at 30, 40, and 150 keV and with various doses. The implantation profiles were confirmed using secondary ion mass spectrometry. X-ray diffraction in combination with Raman and photoluminescence spectroscopies indicated notable crystal damage with the increase of the implantation dose and energy. Significant damage recovery was confirmed after RTA treatment at 300 °C and to a larger extent at 400 °C for a Ge1−xSnx sample with Sn content less than 11%. A GeSn NP diode was fabricated after ion implantation. The device showed rectifying current-voltage characteristics with maximum responsivity and detectivity of 1.29 × 10−3 A/W and 3.0 × 106 cm (Hz)1/2/W at 77 K, respectively.

Effect of tantalum ion implantation on deformation behavior and fracture of TiNi SMA. Part I. quasi-static tension

The effect of high dose implantation of Ta+ ions (Dion = 5′1016 cm−2) into samples from a TiNi shape memory alloy (SMA) on patterns of deformation and fracture mechanisms under quasi-static uniaxial tensile loads was studied. Using X-ray diffractometry, transmission electron microscopy, and scanning electron microscopy, it was shown that ion implantation resulted in amorphization of the surface layer with a thickness of ∼100 nm due to the formation of a chemical composition of approximately Ti36Ni41Ta23 (at.%), thermodynamically corresponding to the highest glass forming ability in the Ti–Ni–Ta system. In the implanted surface layer, both the microstructure and crystal structure defects subsystem were modified at a depth of ∼5 mm. Using the digital image correlation (DIC) method, the dynamics of changes in the integral and local (εyy longitudinal, εxy shear and εxx transverse) strain components were investigated in the tensile tests of both as-received and implanted TiNi SMA samples. On the basis of the obtained results, both integral and local stress–strain diagrams were plotted. In all studied cases, the main contribution to strain accumulation was made by the εyy and εxx strains, which differed significantly for the as-received and implanted TiNi SMA samples. It was concluded that the positive effect of ion implantation was manifested in loading ranges close to the martensitic yield stress (at strain range of 1–6%), despite a noticeable decrease in the ultimate tensile strength and plasticity of the implanted TiNi samples.

Resistance switching stability of STO memristor under Au ion implantation

The alteration in microstructure, induced by ion migration due to applied voltage, constitutes a pivotal factor influencing the performance of the memristor. This phenomenon adversely impacts the stability of the memristor, posing challenges for its practical applications. Notably, the defects present in oxide films, serving as the functional layer in the memristor, assume a crucial role in determining the stability of the artificial synapse—a fundamental component of neuromorphic computing. The precise regulation of defect distribution and density at the nanoscale by growing films directly poses a formidable challenge. In this investigation, a memristor composed of strontium titanate (SrTiO3) was fabricated, exhibiting improved stability in resistive switching during I–V cycles and enhanced multilevel storage performance through the implementation of Au ions implantation. Furthermore, these devices were simulated as neural synapses and integrated into artificial neural networks. A comprehensive array of characterizations was executed to scrutinize the microscopic effects of ion implantation. This involved analyzing changes in elemental composition, structural damage, and spectral characteristics of the films. These findings offer a viable strategy for enhancing the resistive switching performance of oxide thin film devices through the judicious application of ion implantation.

Effect of noble gases ion implantation on the life time of WC-Co tools usedin wood-based material machining

Effect of noble gases ion implantation on the life time of WC-Co tools used in wood-based materialmachining. The results of the investigations on the tool life of WC-Co tools, implanted with three noble gas ions,i.e. helium, neon and argon, are presented in the comparison with the virgin tools and tools implanted withnitrogen ions. The surface modification of the tools was preceded by the modelling of the depth profiles of theimplanted elements. The implantation of the ions of noble gases resulted in an improvement in tool tool life, inthe range from 5 to 49%.

The effects of carbon ion implantation on wettability, abrasion, thermal and anti-corrosion stabilities of laser ablated super-hydrophobic Nitinol surface

Comparing with pure laser irradiation, the hybrid fabrication using laser ablation and chemical modification is one of the widely used techniques to obtain bio-inspired super-hydrophobic surface. Nevertheless, conventional surface chemical modification techniques have faced challenges including the detachment of micro-nano structures and the instability of super-hydrophobic surfaces. This research introduces an innovative method for creating extremely stable super-hydrophobic surfaces on NiTi alloy through a combination of laser exposure, carbon ion implantation, and modification with fluoroalkylsilane (FAS). Surface morphology and chemical component were systematically investigated to reveal the formation mechanism of super-hydrophobicity. Besides, its abrasion stability, thermal stability and corrosion resistance stability of this kind of super-hydrophobic surface were also investigated. And the corresponding stability improvement mechanisms were further revealed.

Enhanced photoresponse of the CdS microwire photodetectors based on indium ion implantation

One-dimensional nano/microstructures have garnered significant attention as the fundamental building blocks for the high-performance integrated systems. Among them, CdS microwires, due to their intriguing optoelectronic properties, hold great promise as candidates for the next generation of high-performance photodetectors. In this study, CdS microwires with wurtzite structure are synthesized using a common chemical vapor deposition method. Optical characterizations revealed that the synthesized microwires exhibited a distinct near band edge emission peak at 515 nm and a broad defect-related emission peak at approximately 650 nm. It is well-known that the intrinsic defects and impurities can significantly degrade the photoresponse properties of the CdS microwire-based photodetectors. To address this issue and enhance the device’s photoresponse performance, indium (In) ion implantation is employed to heal the intrinsic defects. Compared to the pristine CdS microwires, the CdS microwire-based photodetectors with In ion implantation demonstrated a remarkable improvement in photoresponse properties. Specifically, they exhibited a higher responsivity of 390 mA W−1 and external quantum efficiency of 119% (a 94.6-fold increase). The specific detectivity also increased to 3.82 × 107 Jones (a 13-fold increase), while the decay time improved to 652 ms (compared to 3.82 s for pristine devices). Overall, our findings highlight the effectiveness of ion implantation as a strategy to enhance the performance of CdS microwires-based photodetectors. This advancement renders them potentially applicable in integrated photonic, electronic and photoelectric systems.

Investigating on the microstructure and optical properties of Au, Ag and Cu implanted TiN thin films: The effects of surface oxidation and ion-induced defects

In the present paper, the effects of metal ion implantation on the structural and optical properties of TiN thin films have been investigated. TiN films of 170 nm thickness were grown by d.c. reactive sputtering on Si (100) wafers and then irradiated at 5 × 1016 ions/cm2 with either Au, Ag, or Cu ions by using two different energies per each implanted metal. The results showed that as deposited TiN crystallizes in the form of a fcc cubic structure, with the crystallites preferentially oriented along the (111) plane. For all implanted layers, the cubic structure was preserved, but compared to as deposited TiN the crystallites were smaller and the lattice was contracted. These changes were correlated with the depth distribution of Au, Ag and Cu ions and assigned to implantation-induced damage that was larger when higher ion energies were used. High-resolution XPS spectra of the surface of as deposited sample showed the coexistence of TiN, TiO2 and TiOxNy phases and this was related to the surface oxidation of the films due to the exposure to air. After implantation, the results were almost similar for all metals, showing an increase in TiO2 contribution and the formation of pure metallic Au and Ag phases, while copper is in the Cu2+ state, which is attributed to Cu(II)-oxide and Cu(OH)2. The microstructural characteristics including defect formation, changes in crystallite size and lattice contraction, and also growth of different metallic phases during implantations were correlated with the findings of the optical characterization of the implanted films. For the as deposited film we found an energy gap of 2.91 eV, which was lower than the value typical for TiN. After implantation the gap was shifted to higher energies, while at the visible part of the region, the existence of additional energy levels, at photon energies below 2.9 eV was observed. Besides, all implanted films showed degraded photocatalytic activity compared to as deposited TiN, among which Cu-implanted samples exhibited the best photocatalytic performances. The lower photocatalytic activity of Au and Ag implanted films compared to Cu implantations was ascribed to larger structural defects and the formation of less favorable electronic states.

Antioxidation effect of coatings prepared by helium-ion implantation of copper surfaces

The antioxidation effect of a shallow alloying layer introduced by ion implantation is inadequate for many oxidizable metals, limiting its application in antioxidation technology. In this work, the feasibility of preparing an antioxidation coating using ion implantation is explored with the aim of producing copper (Cu) surfaces with strong antioxidation properties. A coating consisted of amorphous carbon and silica is prepared on a Cu surface by helium-ion implantation with pump oil. The formation of the coating is attributed to the bombardment effect of ion implantation and ion beam scanning, which dissociates the bonds of the precursor coating material and drives the redistribution of dissociated species on the Cu surface. During He+ implantation, the C–C and C–O bonds are more likely to break down, resulting in the formation of amorphous carbon. The Si and O combine to form silica because of the high bonding energy of Si–O. The prepared coating exhibits a strong antioxidation effect by blocking the diffusion of Cu cations and enhancing the adhesion of the overlying oxidized film to the substrate. This study demonstrates the feasibility of preparing antioxidation coatings using ion implantation, which could advance the application of ion implantation in antioxidation technology and Cu in microelectronics.

MD simulation study on the microstructural evolution of single-crystal Fe with pre-existing defects by Cr ion implantation

In this study, we present the molecular dynamics simulation of metal ion implantation, investigating the strengthening mechanism from a microstructural perspective. A single crystal Fe with pre-existing defects is constructed based on actual dislocation density and the effects of Cr ion implantation are investigated. Additionally, nanoindentation simulations are conducted to analyze the mechanical properties of workpieces with and without ion implantation. Effects of implantation energy and dose on the microstructure and hardness of workpieces are analyzed. The results indicate that (i) ion implantation introduces FeCr bonds with higher bond energy while reducing the original FeFe bond energy, (ii) increasing implantation energy and dose corresponds to a greater number of point defects and a higher amorphous structures proportion, (iii) the microstructure transformed by ion implantation promotes dislocation nucleation during nanoindentation, (iv) ion implantation enhances workpiece hardness due to the dual effects of interstitials impeding dislocation motion and the heightened mutual obstruction attributed to a higher dislocation density. Notably, the hardness initially enhances with increasing implantation energy and dose, followed by a slight decrease. The computational approach in this paper can serve as a valuable tool for studying the microstructural evolution of metal ion implantation by molecular dynamics simulations.

Influence of dual Mo and Ru ion implantation on the characteristics of commercial TiN-TiAlN-coated WC-10wt%Co-0.5wt%Cr3C2 face milling inserts

The influence of simultaneous dual Mo + Ru ion implantation into commercial TiN and TiAlN hard metal coated WC-10wt%Co-0.5wt%Cr3C2 face milling inserts were investigated at dosages from 5 × 1015 to 1 × 1017 ions/cm2 at 100 keV acceleration voltage. Various characterisation techniques such as field emission scanning electron microscopy, energy dispersive spectroscopy, atomic force microscopy, glancing incident X-ray diffraction, and X-ray photoelectron spectroscopy were used to characterise the microstructure and topography of the as-received and ion implanted samples. The micro-hardness and residual stresses were also determined. Face milling tests were conducted to determine the effect of ion implantation on the wear rate. It has been observed that the dual Mo + Ru ion implantation with a biased Mo content extended 1000 nm into the dual TiN/TiAlN layer with significantly improved microhardness and increased anisotropy between the σ11 and σ22 stress components of the substrate, indicative of related effects in the coatings. The strengthening effect of Ru was observed at all ion implantation dosages even though wt% of Ru was significantly lower than the wt% of Mo. There were no visible changes to the microstructure of the substrate, but the presence of Mo and MoO2 chemical phase contents were observed through XPS. All the ion implantation dosages improved machining performance as the wear rate of the ion implanted face milling inserts was lower than that of as-received TiN and TiAlN coated WC-10wt%Co-0.5wt%Cr3C2 face milling inserts.

Effect of ion implantation on physical, optical properties and gamma-ray shielding capacity of boro-zinc bismuthate glasses

Effect of ion implantation on physical, optical properties and gamma-ray shielding capacity of boro-zinc bismuthate glasses

Synergetic effect of Sb ion implantation on the optical and structural properties of single crystal rutile TiO2 (110)

The present study investigates the synergetic influence of Sb ion implantation on the optical and structural properties of single crystal rutile TiO2 (110). The Implantation was carried out at various fluences using 2 MeV Sb ions. X-ray diffraction, X-ray photoelectron spectroscopy, and Photoluminescence studies reveal the occurrence of an ion-induced annealing process which is remarkably responsible for the healing of defect states in the absence of any thermal treatment. Surprisingly, the ion-induced annealing appears to get activated only for the fluences of 1 × 1015 ions/cm2 and higher. At the fluence of 5 × 1015 ions/cm2, reduction in defect states, increase in crystallinity, increase in the photo absorption response (130 % in visible and 165 % in ultraviolet range), improved band-edge luminescence, and bandgap reduction (by ∼0.26 eV) is observed. The ion-induced annealing process effectively improves photo absorption properties without any thermal treatment. These results can play a pivotal role in photocatalysis applications.

Cutting performance assessment on the modified single crystal diamond tool by focused ion beam

In this work, the ion implantation effect of focused ion beam (FIB) is employed to modify the single crystal diamond tools, and the cutting performances of the irradiated and unirradiated tools are further evaluated. Firstly, the characteristics of the irradiated rake face are measured to determine the impact of the implanted ions. The results show that the surface energy of the rake face irradiated by FIB decreases significantly. Secondly, cutting experiments are carried out on the Al6061 alloy substrates. The results demonstrate that the ion implantation improves the self-cleaning of rake face and the wear resistance of cutting edge, which is conducive to reduce the cutting force and cutting temperature, resulting in an improvement of the manchined surface quality. All the experimental observations confirm that the FIB implantation process is an effective method to improve the cutting performance of single crystal diamond tool.

Disclosing the annihilation effect of ion-implantation induced defects in single-crystal diamond by resonant MEMS

Single-crystal diamond presents as an ideal semiconductor material for high-performance and high-reliability MEMS devices, on account of its outstanding mechanical and physical properties. A smart-cut technology based on ion-implantation was proposed to fabricate the SCD-on-SCD MEMS resonators. However, the ion-implantation damage induced defects would degrade the quality (Q) factors of the diamond MEMS resonators. Here, we systematically investigate the effect of ultra-high vacuum annealing on the resonance properties of SCD cantilevers. It is observed that the Q factors are markedly improved by nearly twice after annealing at 1100 °C due to the annihilation of the ion implantation induced damage in the resonators. Therefore, reducing the defects in the resonators by high-temperature annealing the as-fabricated SCD MEMS cantilevers is one of the strategies to improve the Q factors. This work also proves out that MEMS represents a more sensitive tool for characterizing the crystalline quality of diamond, compared with the conventional structural methods.