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1.
《Composite Interfaces》2013,20(2-3):229-238
Physical and chemical properties changes in a polymer have been studied for polycarbonate (PC) implanted with 100 keV Ni+ ions with varying fluence from 1 × 1014 to 1 × 1016 ions/cm2. The changes in the surface morphology and composition have been observed with atomic force microscopy (AFM) and X-ray diffraction (XRD). The ions implanted induce changes in topography of PC and indicate that the roughness increases dramatically with ion fluence. Implanted metal ions shows direct evidence of compound formation on the surface. The chemical changes in the surface region have been carried out by Raman Spectroscopy and UV-VIS spectroscopy. UV-VIS absorption analysis indicates a drastic decline in optical band gap from 5.46 eV to 1.76 eV at an implanted dose of 1 × 1016 ions/cm2. It could be shown that the partial destruction of chemical bonding under ion implantation leads to the creation of new amorphous and graphite-like structures, which is confirmed by Raman spectroscopy. 相似文献
2.
采用离子注入法制备了钴离子掺杂的金红石相TiO2样品;离子注入能量、注量分别为40 keV(1×1016cm-2),80 keV(5×1015,1×1016,5×1016,1×1017cm-2),120 keV(1×1016cm-2). 通过XRD,XPS和UV-Vis等手段对掺杂前后样品的结构和光学性能进行了表征,分析了掺杂元素在金红石TiO2中的存在形式. XRD测试表明随着注入能量的增加晶体的损伤程度增加. UV-Vis测试表明掺杂后所有样品在可见光区的吸收增强; 并且随着注量的增加,注量为5×1015cm-2到5×1016cm-2范围内注入样品的光学带隙逐渐变小.
关键词:
钴
二氧化钛
离子注入
掺杂 相似文献
3.
TiO2 thin film synthesized by the RF sputtering method has been implanted by 120 keV Ag? ion with different doses (3?×?1014, 1?×?1015, 3?×?1015, 1?×?1016 and 3?×?1016 ions/cm2). Further, these were characterized by Rutherford back Scattering, XRD, X-ray photoelectron spectroscopy (XPS), UV–visible and fluorescence spectroscopy. Here we reported that after implantation, localized surface Plasmon resonance has been observed for the fluence 3?×?1016 ions/cm2, which was due to the formation of silver nanoparticles. Ag is in metallic form in the matrix of TiO2, which is very interestingly as oxidation of Ag was reported after implantation. Also, we have observed the interaction between nanoparticles of Ag and TiO2, which results in an increasing intensity in lower charge states (Ti3+) of Ti. This interaction is supported by XPS and fluorescence spectroscopy, which can help improve photo catalysis and antibacterial properties. 相似文献
4.
5.
S. Saravana Kumar M. Abdul Khadar K. G. M. Nair S. Dhara P. Magudapathy 《Journal of Raman spectroscopy : JRS》2008,39(12):1900-1906
ZnS nanocrytsals of size ∼2.5 nm were prepared by chemical precipitation technique. Pressed pellets of nanostructured ZnS were implanted with He+ ions at doses of 5 × 1014, 1 × 1015 and 5 × 1015 ions/cm2. Raman spectra of both unimplanted and He+ ion implanted samples were recorded with ultraviolet (UV) excitation. LO, 2LO, 2TO, (LO + TA) and (2TO − TA) modes of ZnS were observed in the resonance Raman spectra of the unimplanted nanostructured ZnS samples. In addition, a surface mode was observed at 294 cm−1. With the implantation of He+ ions, the 2TO mode disappeared and 2LO mode became prominent and this observation was attributed to the decrease in band gap of ZnS nanocrytsals due to ion implantation. The exciton–LO phonon coupling strength was determined from the intensity ratio of 2LO to LO modes and it was observed that the exciton–LO phonon coupling strength increases with increase in implantation dose. In the present work, we report for the first time the observation of 2TO mode in the resonance Raman spectrum of nanostructured ZnS and also the modification of exciton–LO phonon coupling strength of semiconductor nanoparticles by ion implantation. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
6.
Ranajit Dey 《辐射效应与固体损伤》2018,173(3-4):283-299
Implanted Au5+-ion-induced modification in structural and phonon properties of phase pure BiFeO3 (BFO) ceramics prepared by sol–gel method was investigated. These BFO samples were implanted by 15.8?MeV ions of Au5+ at various ion fluence ranging from 1?×?1014 to 5?×?1015?ions/cm2. Effect of Au5+ ions’ implantation is explained in terms of structural phase transition coupled with amorphization/recrystallization due to ion implantation probed through XRD, SEM, EDX and Raman spectroscopy. XRD patterns show broad diffuse contributions due to amorphization in implanted samples. SEM images show grains collapsing and mounds’ formation over the surface due to mass transport. The peaks of the Raman spectra were broadened and also the peak intensities were decreased for the samples irradiated with 15.8?MeV Au5+ ions at a fluence of 5?×?1015?ion/cm2. The percentage increase/decrease in amorphization and recrystallization has been estimated from Raman and XRD data, which support the synergistic effects being operative due to comparable nuclear and electronic energy losses at 15.8?MeV Au5+ ion implantation. Effect of thermal treatment on implanted samples is also probed and discussed. 相似文献
7.
ABSTRACTIn the present work, effects of silicon negative ion implantation into semi-insulating gallium arsenide (GaAs) samples with fluences varying between 1?×?1015 and 4?×?1017?ions?cm?2 at 100?keV have been described. Atomic force microscopic images obtained from samples implanted with fluence up to 1?×?1017?ion?cm?2 showed the formation of GaAs clusters on the surface of the sample. The shape, size and density of these clusters were found to depend on ion fluence. Whereas sample implanted at higher fluence of 4?×?1017?ions?cm?2 showed bump of arbitrary shapes due to cumulative effect of multiple silicon ion impact with GaAs on the same place. GXRD study revealed formation of silicon crystallites in the gallium arsenide sample after implantation. The silicon crystallite size estimated from the full width at half maxima of silicon (111) XRD peak using Debye-Scherrer formula was found to vary between 1.72 and 1.87?nm with respect to ion fluence. Hall measurement revealed the formation of n-type layer in gallium arsenide samples. The current–voltage measurement of the sample implanted with different fluences exhibited the diode like behavior. 相似文献
8.
S. Chandramohan A. Kanjilal S. N. Sarangi S. Majumder R. Sathyamoorthy T. Som 《Applied Physics A: Materials Science & Processing》2010,99(4):837-842
We report on effects of Fe implantation doping-induced changes in structural, optical, morphological, and vibrational properties
of cadmium sulfide thin films. Films were implanted with 90 keV Fe+ ions at room temperature for a wide range of fluences from 0.1×1016 to 3.6×1016 ions cm−2 (corresponding to 0.38–12.03 at.% of Fe). Glancing angle X-ray diffraction analysis revealed that the implanted Fe atoms
tend to supersaturate by occupying the substitutional cationic sites rather than forming metallic clusters or secondary phase
precipitates. In addition, Fe doping does not lead to any structural phase transformation although it induces structural disorder
and lattice contraction. Optical absorption studies show a reduction in the optical band gap from 2.39 to 2.17 eV with increasing
Fe concentration. This is attributed to disorder-induced band tailing in semiconductors and ion-beam-induced grain growth.
The strain associated with a lattice contraction is deduced from micro-Raman scattering measurements and is found that size
and shape fluctuations of grains, at higher fluences, give rise to inhomogeneity in strain. 相似文献
9.
Jiandong Zhang Jiangtao Zhao Weilin Jiang Xingcai Guan Haibo Peng Zihua Zhu 《辐射效应与固体损伤》2013,168(11-12):1027-1036
ABSTRACTTungsten (W) has been regarded as one of the most promising plasma facing materials (PFMs) in fusion reactors. The formation of bubbles and blisters during hydrogen (H) irradiation will affect the properties of W. The dependence of implantation conditions, such as fluence and energy, is therefore of great interest. In this work, polycrystalline tungsten samples were separated into two groups for study. The thick samples were implanted by 18?keV H3+ ions to fluences of 1?×?1018, 1?×?1019 and 1?×?1020 H+/cm2, respectively. Another thick sample was also implanted by 80?keV H2+ ions to a fluence of 2?×?1017 H+/cm2 for comparison. Moreover, the thin samples were implanted by 18?keV H3+ ions to fluences of 9.38?×?1016, 1.88?×?1017 and 5.63?×?1017 H+/cm2, respectively. Focused ion beam (FIB) combined with scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used for micro-structure analysis, while time-of-flight ion mass spectrometry (ToF-SIMS) was used to characterize the H depth profile. It is indicated that bubbles and blisters could form successively with increasing H+ fluence. H bubbles are formed at a fluence of ~5.63?×?1017 H+/cm2, and H blisters are formed at ~1?×?1019 H+/cm2 for 18?keV H3+ implantation. On the other hand, 80?keV H2+ ions can create more trapping sites in a shallow projected range, and thus enhancing the blisters formation with a relatively lower fluence of 2?×?1017?H+/cm2. The crack-like microstructures beneath the blisters are also observed and prefer to form on the deep side of the implanted range. 相似文献
10.
K. M. Abhirami P. Matheswaran B. Gokul R. Sathyamoorthy K. Asokan 《Applied Physics A: Materials Science & Processing》2013,111(4):1175-1180
SnO2 thin films grown on glass substrates at 300 °C by reactive thermal evaporation and annealed at 600 °C were irradiated by 120 MeV Ag9+ ions. Though irradiation is known to induce lattice disorder and suppression of crystallinity, we observe grain growth at a certain fluence of irradiation. X-ray diffraction (XRD) revealed the crystalline nature of the films. The particle size estimated by Scherrer’s formula for the irradiated films was in the range 10–25 nm. The crystallite size increases with increase in fluence up to 1×1012 ions?cm?2, whereas after that the size starts decreasing. Atomic force microscope (AFM) results showed the surface modification of nanostructures for films irradiated with fluences of 1×1011 ions?cm?2 to 1×1013 ions?cm?2. The UV–visible spectrum showed the band gap of the irradiated films in the range of 3.56 eV–3.95 eV. The resistivity decreases with fluence up to 5×1012 ions?cm?2 and starts increasing after that. Rutherford Backscattering (RBS) reveals the composition of the films and sputtering of ions due to irradiation at higher fluence. 相似文献
11.
É. Z. Kurmaev D. A. Zatsepin S. O. Cholakh B. Schmidt Y. Harada T. Tokushima H. Osawa S. Shin T. Takeuchi 《Physics of the Solid State》2005,47(4):754-757
The local structure of the chemical bond of iron ions implanted into SiO2 glasses (implantation energy, 100 keV; fluence, 1 × 1016 cm?2) is investigated using x-ray emission and absorption spectroscopy. The Fe L x-ray emission and absorption spectra are analyzed by comparing them with the corresponding spectra of reference samples. It is established that iron nanoparticles implanted into the SiO2 vitreous matrix are in an oxidized state. The assumption is made that the most probable mechanism of transformation of iron nanoparticles into an oxidized state during implantation involves the breaking of Si-O-Si bonds with the formation of Si-Si and Fe-O bonds. 相似文献
12.
Transition Metal (TM) ions V, Cr, Mn and Co were implanted into GaN/sapphire films at fluences 5×1014, 5×1015 and 5×1016 cm−2. First order Raman Scattering (RS) measurements were carried out to study the effects of ion implantation on the microstructure of the materials, which revealed the appearance of disorder and new phonon modes in the lattice. The variations in characteristic modes 1GaN i.e. E2(high) and A1(LO), observed for different implanted samples is discussed in detail. The intensity of nitrogen vacancy related vibrational modes appearing at 363 and 665 cm−1 was observed for samples having different fluences. A gallium vacancy related mode observed at 277/281 cm−1 for TM ions implanted at 5×1014 cm−2 disappeared for all samples implanted with rest of fluences. The fluence dependent production of implantation induced disorder and substitution of TM ions on cationic sites is discussed, which is expected to provide necessary information for the potential use of these materials as diluted magnetic semiconductors in future spintronic devices. 相似文献
13.
U. Dadwal R. Scholz M. Reiche P. Kumar S. Chandra R. Singh 《Applied Physics A: Materials Science & Processing》2013,112(2):451-456
GaN epitaxial layers were implanted by 100 keV H+ ions at different implantation temperatures (LN2, RT and 300 °C) with a fluence of 2.5×1017 cm?2. The implanted samples were characterized using Nomarski optical microscopy, AFM, XRD, and TEM. Topographical investigations of the implanted surface revealed the formation of surface blistering in the as-implanted samples at 300 °C and after annealing at higher temperature for the implantation at LN2 and RT. The physical dimensions of the surface blisters/craters were dependent on the implantation temperature. XRD showed the dependence of damage-induced stress on the implantation temperature with higher stress for the implantation at 300 °C. TEM investigations revealed the formation of a damage band in all the cases. The damage band was filled with large area microcracks for the implantation at 300 °C, which were responsible for the as-implanted surface blistering. 相似文献
14.
Pure iron foils were implanted with nitrogen ions at energy of 10 keV and with 1×1017N ions/cm2. Doses of pre-self-implantation were 5×1016 and 3.7×1016
17Fe ions/cm2 respectively, and the iron ion energy was 27 keV. A comparison of iron nitrides formed on surfaces with and without pre-self-implantation
has been obtained. The results show that radiation damage apparently influences the formation of iron nitrides. The formation
and transformation of nitrides after N implantation or after annealing can be explained by a model of implantation-induced
transformation. 相似文献
15.
Boron implanted 4145 steel was evaluated for changes in the near-surface region property such as microhardness. The surfaces when implanted with 11B+ ions at 135 keV energy to a dose 1 × 1017 ions cm?2 resulted in increase of microhardness for 10 to 40 gms of applied load. An increase upto 40% in microhardness could be observed in the specimen when annealed at 310δC for 3 hours. Furthermore, the effect of ion-beam induced intermixing of 250Å thin carbon film due to boron implantation was also studied for different doses ranging from 1 × 1017 to 3 × 1017 boron ions cm?2. An increase in microhardness with applied load was observed for 1 × 1017 ions cm?2 concentration, while hardest layer was formed at 3 × 1017 ions cm?2 dose which practically had very little effect to 10 and 20 gms of load. 相似文献
16.
Samarium (Sm) ions of 200 keV in energy were implanted into highly-resistive molecular-beam-epitaxy grown GaN thin films with a focused-ion-beam implanter at room temperature. The implantation doses range between 1014 and 1016 cm−2. X-ray diffraction revealed Sm incorporation into GaN matrix without secondary phase. Raman-scattering spectroscopy identified impurity-independent defect-related oscillation modes. Slight decrease in band gap and significant reduction in transmittance were observed by optical transmission spectroscopy. Photoluminescence spectra showed emission peaks related to background p-type impurity. Ferromagnetic hysteresis loops were recorded from GaN implanted with highest Sm dose, and magnetic ordering was observed from Sm-implanted GaN with dose of and above 1015 cm−2. The long-range magnetic ordering can be attributed to interaction of Sm ions through the implantation-induced Ga vacancy. 相似文献
17.
18.
A. A. Kharchenko M. G. Lukashevich V. I. Nuzhdin R. I. Khaibullin V. B. Odzhaev 《Physics of the Solid State》2013,55(1):88-93
The magnetic characteristics of polyimide films implanted with Co+ ions with an energy of 40 keV in the dose range D = 2.50 × 1016?1.25 × 1017 cm?2 at ion current densities j = 4, 8, and 12 μA/cm2 have been investigated. It has been shown that, at implantation doses of less than 5 × 1016 cm?2, the superparamagnetic properties of modified samples are described by the Langevin equation. At higher doses, there is an intercluster interaction. It has been found that, with an increase in the ion current, the cluster size decreases. The sizes of the formed clusters are determined and vary in the range from 3.9 to 11.0 nm, depending on the implantation dose. 相似文献
19.
Lakhwant Singh 《Journal of Macromolecular Science: Physics》2013,52(5):1041-1049
Polycarbonate (Makrofol‐N) thin films were irradiated with protons (3 MeV) under vacuum at room temperature with the fluence ranging from 1×1014 to 1×1015 protons cm?2. The change in surface morphology, optical properties, degradation of the functional groups, and crystallinity of the proton‐irradiated polymers were investigated with atomic force microscopy (AFM), UV‐VIS, and Fourier‐transform infrared (FTIR) spectroscopy, and X‐ray diffraction (XRD) techniques, respectively. AFM shows that the root mean square (RMS) roughness of the irradiated polycarbonate surface increases with the increment of ion fluence. The UV‐VIS analysis revealed that in Makrofol‐N the optical band gap decreased by 30% at highest fluence of 1×1015 protons cm?2. The band gap can be correlated to the number of carbon atoms, M, in a cluster with a modified Robertson's equation. The cluster size in the proton‐irradiated Makrofol‐N increased from 112 to 129 atoms with the increase of fluence from 1×1014 to 1×1015 protons cm?2. FTIR spectra of proton (3 MeV) irradiated Makrofol‐N showed a strong decrease of almost all absorption bands at about 1× 1014 protons cm?2. However, beyond a higher critical dose an increase in intensity of almost all characteristic bands was noticed. The appearance of a new peak at 3,500 cm?1 (‐OH groups) was observed at the higher fluences in the FTIR spectra of proton‐irradiated polycarbonate. XRD measurements showed an increase of full width at half maximum (FWHM) and the average intermolecular spacing of the main peak, which may be due to the increase of chain scission and the introduction of ‐OH groups in the proton irradiated polycarbonate. 相似文献
20.
Abstract Continuous, incoherent light from a xenon arc lamp has been used to anneal radiation damage in <100> silicon single crystals produced by implantation of 30?keV arsenic or antimony ions to doses between 1×1015 cm?2 and 1×1016 cm?2. The recrystallized layers have been characterized by Rutherford-backscattering spectroscopy, ion-channeling, Transmission Electron Microscopy, and sheet-resistivity measurements. 相似文献