Thermally grown amorphous SiO 2 (a-SiO 2 ) films were implanted at room temperature (RT) with 100 keV C-ions to 5.0×10 17 ions/cm 2 . These samples were irradiated at RT with 853 MeV Pb-ions to 1.0×10 12 and 5.0×10 12 ions/cm 2 . Then the samples were investigated using Transmission Electron Microscopy (TEM) at RT. Significant microstructure modifications were observed in C-doped a-SiO 2 /Si samples after high energy Pb-ion irradiations, and the formation of new structures depended strongly on the Pb-ion irradiation fluences. For example, tracks in high density were observed in a 1.0×10 12 Pb/cm 2 irradiated and C-doped sample. Additionally, the length of tracks grows, and a large number of 8H-SiC nanocrystals can be seen in the film when irradiation fluence is increased to 5.0×10 12 Pb/cm 2 . Possible modification processes of C-doped a-SiO 2 under swift heavy ion irradiations are briefly discussed.

The effects of 100 keV H-ion implantation on the structure of LiTaO3 crystal are investigated by Raman and UV/VIS/NIR spectroscopies. The implantation fluence is in the range from 1.0 × 1013 to 1.0 × 1017 H+/cm2. The experimental results show the dependence of the crystal structure on ion fluence. It is found that the structural modification of the LiTaO3 crystal is due to two processes. One is H-ions occupying lithium vacancies (VLi), which is predominant at a fluence less than 1.0 × 1014 H+/cm2. This process causes the reduction of negative charge centers in the crystal and relaxation of distortion in the local lattice structure. The other is the influence of defects created during implantation, which plays a dominant role gradually in the structural modification at a fluence larger than 1.0 × 1015 H+/cm2.

Polystyrene (PS) films were irradiated with 1.157GeV 56Fe ions at room temperature to fluences of 1×1012ions/cm2 at various electronic energy loss values. Ultraviolet–visible (UV–vis) spectra were measured to investigate the optical properties of the irradiated materials. Optical constants of virgin and irradiated PS were evaluated in the UV–vis frequence range through fitting of UV–vis spectra with the multi-Lorentz model. Furthermore, effective medium theory was applied to evaluate the optical constants of materials in the ion track area. It is found that the refractive index of ion track material decreased significantly in the ultraviolet–visible range whereas its extinction coefficient increased. Gas atom release and carbon atom conglomerating are believed to be the reason. The extracted track radius and its variation with electronic energy loss values are in good agreement with earlier studies.

The structural modification of C-60 films induced by 300-keV Xe-ion irradiation was investigated. The irradiated C-60 films were analysed using Fourier transform infrared spectroscopy, the Raman scattering technique, ultraviolet/visible spectrophotometry and atomic force microscopy. The analysis results indicate that the Xe-ion irradiation induces polymerization and damage of the C-60 molecule and significantly modifies the surface morphology and the optical property of the C-60 films. The damage cross-section for the C-60 molecule was also evaluated.

In order to investigate the potential effect in the C60 films induced by slow highly-charged ion(SHCI), the irradiation experiments of C60 films were performed by using Xen+ ions(n=3, 10, 13, 15, 17, 20, 22, 23). The irradiated C60 films were analyzed by means of AFM and Raman scattering. The analysis results indicated that the surface roughness of C60 films irradiated is decreasing with the increase of the charge state of Xen+ ions(potential energy stored in Xen+ ions).This reveals the existing of the potential effect. The results of the Raman spectra showed that in despite of existing influence of potential effect, the damage process of C60 films in the area for analysis depth of Raman is dominated by the elastic collisions, because the deposited potential energy of Xen+ ion in C60 films is much less than its kinetic energy.

The structural stability of C60 films under the bombardment of 1.95 GeV Kr ions is investigated. The irradiated C60 films were analyzed by Fourier Transform Infrared (FTIR) spectroscopy and Raman scattering technique. The analytical results indicate that the irradiation induced a decrease of icosahedral symmetry of C60 molecule and damage of C60 films; different vibration modes of C60 molecule have different irradiation sensitivities; the mean efficient damage radius obtained from experimental data is about 1.47 nm, which is in good agreement with thermal spike model prediction.

Irradiation effect in C60 films induced by 170 keV B ion was investigated by means of Fourier transform infrared (FTIR) and Raman spectroscopies. The damage cross section σ and the effective damage radius R are deduced from the experimental data of all four IR active modes and evident four Raman active modes of C60 molecule. The differences on irradiation sensitivity and structural stability of the different active modes of C60 molecule are compared. The results indicate that T1u (4) of infrared active mode and Ag (1) of Raman active mode are most sensitive for B ion irradiation. On the other hand T1u (2) of infrared active mode and Hg (3) of Raman active mode are comparatively stable under B ion irradiation.

Silica glass samples were implanted with 1.157 GeV Fe-56 and 1.755 GeV Xe-136 ions to fluences range from 1 x 10(11) to 3.8 x 10(12) ions/cm(2). Virgin and irradiated samples were investigated by ultraviolet (UV) absorption from 3 to 6.4 eV and photoluminescence (PL) spectroscopy. The UV absorption investigation reveals the presence of various color centers (E' center, non-bridging oxygen hole center (NBOHC) and ODC(II)) appearing in the irradiated samples. It is found that the concentration of all color centers increase with the increase of fluence and tend to saturation at high fluence. Furthermore the concentration of E' center and that of NBOHC is approximately equal and both scale better with the energy deposition through processes of electronic stopping, indicating that E' center and NBOHC are mainly produced simultaneously from the scission of strained Si-O-Si bond by electronic excitation effects in heavy ion irradiated silica glass. The PL measurement shows three emissions peaked at about 4.28 eV (alpha band), 3.2 eV (beta band) and 2.67 eV (gamma band) when excited at 5 eV. The intensities of alpha and gamma bands increase with the increase of fluence and tend to saturation at high fluence. The intensity of beta band is at its maximum in virgin silica glass and it is reduced on increasing the ions fluence. It is further confirmed that nuclear energy loss processes determine the production of alpha and gamma bands and electronic energy loss processes determine the bleaching of beta band in heavy ion irradiated silica glass. (c) 2009 Elsevier B.V. All rights reserved.

Irradiation effect in three carbon allotropes C60, diamond and highly oriented pyrolytic graphite (HOPG) induced by 170 keV B ions, mainly including the process of the damage creation, is investigated by means of Raman spectroscopy technique. The differences on irradiation sensitivity and structural stability for C60, HOPG and diamond are compared. The analysis results indicate that C60 is the most sensitive for B ions irradiation, diamond is the second one and the structure of HOPG is the most stable under B ion irradiation. The damage cross sections σ of C60, diamond and HOPG deduced from the Raman spectra are 7.78 × 10−15, 6.38 × 10−15 and 1.31 × 10−15 cm2, respectively.

Ni/SiO_2 interface were irradiated at room temperature with 308 MeV Xe ions to 1×10~(12), 5×10~(12) Xe/cm~2 and 853 MeV Pb ions to 5× 10~(11) Pb/cm~2, respectively. These samples were analyzed using Rutherford Backscattering Spectrometry (RBS) and X-ray diffraction spectroscopy (XRD) , from which the intermixing and phase change were investigated. The obtained results show that both Xe- and Pb-ions could induce diffusion of Ni atoms to SiO_2 substrates and result in intermixing of Ni with SiO_2. Furthermore, 1.0×10~(12) Xe/cm~2 irradiation induced the formation of NiSi_2 and 5.0×10~(12) Xe/cm~2 irradiation created Ni_3 Si and NiO phases. The diffusion of Ni atoms and the formation of new phase may be driven by a transient thermal spike process induced by the intense electronic energy loss along the incident ion path.

Low-activation Ferritic/Martensitic steels are a kind of important structural materials candidate to the application in advanced nuclear energy systems.Possible degradation of properties and even failure in the condition of high-temperature and high helium production due to energetic neutron irradiation in a fusion reactor is a major concern with the application of this kind of materials.In the present work microstructural evolution in a 9Cr Ferritic/Martensitic steel(T92B) irradiated with 122 MeV 20Ne ions at temperatures between 0.3—0.5 Tm(Tm is the melting point of the material) was investigated with transmission electron microscopy.High concentration voids were observed in the specimens irradiated at high temperatures when the displacement damage dose and Ne concentration exceed a certain level.Preferential formation of voids at lath-boundaries and other grain-boundaries was found.The data of void swellings in 9Cr ferritic/martensitic steels irradiated in different conditions(such as with He-ions,Ne-ions,Fe/He dual beams,fast neutrons,Ni-ions etc.) were compiled and analyzed based on a classic model of helium bubble formation,and bubble to void transition.

Amorphous SiO2 thin films with about 400-500 nm in thickness were thermally grown on single crystalline silicon. These SiO2/Si samples were firstly implanted at room temperature (RT) with 100 keV carbon ions to 2.0 x 10(17),5.0 X 10(17) or 1.2 x 10(18) ions/cm(2), then irradiated at RT by 853 MeV Pb ions to 5.0 x 10(11), 1.0 X.10(12) 2.0 x 10(12) or 5.0 x 10(12) ions/cm(2), respectively. The variation of photoluminescence (PL) properties of these samples was analyzed at RT using a fluorescent spectroscopy. The obtained results showed that Pb-ion irradiations led to significant changes of the PL properties of the carbon ion implanted SiO2 films. For examples, 5.0 x 10(12) Pb-ions/cm(2) irradiation produced huge blue and green light-emitters in 2.0 x 10(17) C-ions/cm(2) implanted samples, which resulted in the appearance of two intense PL peaks at about 2.64 and 2.19 eV. For 5.0 x 10(17) carbon-ions/cm(2) implanted samples, 2.0 x 10(12) Pb-ions/cm(2) irradiation could induce the formation of a strong and wide violet band at about 2.90 eV, whereas 5.0 x 10(12) Pb-ionS/cm(2) irradiation could,create double peaks of light emissions at about 2.23 and 2.83 eV. There is no observable PL peak in the 1.2 x 10(18) carbon-ions/cm(2) implanted samples whether it was irradiated with Pb ions or not. All these results implied that special light emitters could be achieved by using proper ion implantation and irradiation conditions, and it will be very useful for the synthesis of new type Of SiO2-based light-emission materials.

In this paper, an investigation on the micro-structure of an Fe-base oxide-dispersion-strengthened (ODS) alloy irradiated with high-energy 20Ne ions to different doses at a temperature around 0.5T m (T m is the melting point of the alloy) is presented. Investigation with the transmission electron microscopy found that the accelerated growth of voids at grain-boundaries, which is usually a concern in conventional Fe-base alloys under conditions of inert-gas implantation, was not observed in the ODS alloy irradiated even to the highest dose (12000 at.ppm Ne). The reason is ascribed to the enhanced recombination of point defects and strong trapping of Ne atoms at the interfaces of the nano-scale oxide particles in grains. The study showed that ODS alloys have good resistance to the high-temperature inter-granular embrittlement due to inert-gas accumulation, exhibiting prominence of application in harsh situations of considerable helium production at elevated temperatures like in a fusion reactor.

Surface change of gallium nitride specimens after bombardment by highly charged Pbq+-ions (q = 25, 35) at room temperature is studied by means of atomic force microscopy. The experimental results reveal that the surface of GaN specimens is significantly etched and erased. An unambiguous step-up is observed. The erosion depth not only strongly depends on the charge state of ions, but also is related to the incident angle of Pbq+-ions and the ion dose. The erosion depth of the specimens in 60° incidence (tilted incidence) is significantly deeper than that of the normal incidence. The erosion behaviour of specimens has little dependence on the kinetic energy of ion (Ek = 360,700keV). On the other hand, surface roughness of the irradiated area is obviously decreased due to erosion compared with the un-irradiated area. A flat terrace is formed.

Zinc oxide films with c-axis preferred orientation were deposited on silicon (100) substrates by radio frequency (RF) reactive sputtering. The properties of the samples were characterized by X-ray diffractometer, X-ray photoelectron spectroscopy and fluorescent-spectrophotometer. The effect of sputtering power and substrate temperature on the structural and photoluminescent (PL) properties of the ZnO films was investigated. The results indicated that when the sputtering power is 100 W and the substrate temperature is 300–400°C, it is suitable for the growth of high c-axis orientation and small strain ZnO films. A violet peak at about 380 nm and a blue band at about 430 nm were observed in the room temperature photoluminescence spectra, and the origin of blue emission was investigated.

用射频反应溅射在硅(100)衬底上生长了c轴择优取向的ZnO薄膜,用X射线衍射仪、荧光分光光度计和X射线光电子能谱仪对样品进行了表征,分析研究了溅射功率、衬底温度对样品的结构和发光特性的影响.结果表明,溅射功率100W,衬底温度300～400℃时,适合c轴择优取向和应力小的ZnO薄膜的生长.在样品的室温光致发光谱中观察到了380nm的紫外激子峰和峰位在430 nm附近的蓝光带,并对蓝光带的起源进行了初步探讨.

Diamond-like-carbon films and graphite samples were implanted at room temperature(RT) using 100—120 keV N-ions to 5 × 1017 - 5 × 1018 cm-2,and then irradiated at RT using 345 MeV Xe,2.64 GeV U or 30 MeV C60 ions,respectively. The irradiated samples were characterized by FTIR,Raman,and XRD or XPS spectroscopes,and the formation of new chemical bonds and phases in the N-doped samples induced by heavy ion irradiations were studied. It was found that high-energy heavy ion irradiations could significantly induce the formation of CN bonds in all samples,high N-concentration and intense energy deposition result in the increment of sp3/sp2 bonding ratio and the enhancement of the formation of N-sp3C bonds that are needed for α-and β-C3N4 phase production. Furthermore,C60 ion irradiation could result in the formation of CNx and tetrahedral amorphous carbon in the C-doped graphite samples,whereas high-energy Xe and U ions could produce α-and β-C3N4 crystalline inclusions in the C-doped diamond-like-carbon samples.

Thermally grown amorphous SiO2 films on single crystalline silicon were implanted at room temperature(RT) with 120keV C ions to 2.0 × 1017～8.6 × 1017 cm-2,then irradiated at RT by high energy Xe,U and Pb ions to 1.0 × 1010 ～ 3.8 × 1012 cm-2. The variation of chemical bonding configuration in these samples induced by high energy ion bombardments was investigated using Fourier Transformation Infrared(FTIR) spectroscopy. The obtained results showed that a large amount of Si-O-C and Si-C bonds was formed in the heavy ion irradiated C-doped amorphous SiO2 films. The SiOC bonds are of cage-,ring-or open-linked structures,and the cage-linked structure tends to ring-/open-linked structure with the increase of heavy ion irradiation fluence,electronic energy loss,or deposited energy density in the samples. The mechanism of SiOC formation induced by high energy heavy ion irradiations was briefly discussed.

The irradiation effects of C_(60) films induced by 0.98 GeV Fe ions at the same electronic energy loss of 3.5 keV/nm and different irradiation dose ranging from 5×1010 to 8×1013 ions/cm2,were analyzed by Raman scattering and Fourier transform infrared(FTIR) spectroscopes.The analysis results indicate that the irradiation results in a molecular polymerization and destruction of the C60.The partial recovery of the damage at the intermediate value of irradiation dose,1×1012 ions/cm2,was caused by an annealing effect of electronic energy loss.The ion track or damage cross-section σ deduced from the Raman data was 1.32×10-14 cm~2.