Surface modification of PET membrane by ion implantation

Semicrystalline poly(ethylene terephtalate) (PET) foils were irradiated with N⁵⁺, O⁷⁺ and C³⁺ ions. Ions beams of 50 keV N⁵⁺, 70 keV O⁷⁺ and 30 keV C³⁺ were produced from the ECR ion source. The induced effects and wettability of ion-implanted membranes were investigated by means of the Fourier transform infrared spectroscopy (FTIR), atomic force microscopy (AFM) and by the contact-angle methods. FTIR measurements of the virgin and irradiated samples show the scission processes of main chains at the ethylene glycol residue. Various degradation processes known from photochemical degradation were also observed. The AFM observation revealed that the surface topography changes after irradiation. The contact-angle measurements showed that the PET membranes became significantly more hydrophilic after the ion irradiation.     

Optical propagation modified by Cu nanoparticle grating fabricated by heavy ion implantation

The optical propagation property of a planar waveguide with a periodic nanoparticle grating layer is characterized by using sliding prism method. Here, Cu nanoparticle grating was fabricated on a-SiO₂ substrate by periodic heavy-ion irradiation technique. The pitch of these gratings was 2 μm and 3 μm, respectively. The flux and fluence were at the range of 6-10 μA/cm² and 6 × 10¹⁶-1 × 10¹⁷ ions/cm², respectively. The grating effect, mainly including the mode selection effect, is observed. The effect depends on the pitch of the grating and the morphology of nanoparticles. The propagation loss of the waveguide induced by nanoparticle layer is evaluated.     

MEVVA离子注入铁镍银对DSSCs光电性能的影响

利用MEVVA技术分别将金属Fe、Ni、Ag离子注入进DSSCs结构中作为电荷传输层的TiO_2膜,表征了各金属离子注入后TiO_2膜表面形貌及晶相结构,研究了DSSCs注入前后光电性能及电池内部界面的电荷传输变化。能带理论分析显示,金属离子注入后,TiO_2能带结构发生变化,并在其禁带中引入了杂质能级,不仅优化了TiO_2导带与染料LUMO能级匹配度,而且杂质能级为电荷的传输提供了额外传输"通道",从而降低了电荷传输过程中的复合率。DSSCs光电性能测试结果显示,与未注入的DSSCs相比,Fe、Ni、Ag离子注入DSSCs的光电转化率分别提高了13.6%、12.7%、34.2%。     

N等离子体基注渗方法研究

等离子体基注渗技术在材料表面改性中具有极为重要的应用，本文报道了一种实现恒温条件的N等离子体基注渗的工艺方法，利用该方法可以根据工艺研究需要，实现注渗剂量、注渗能量(加速电压)和注渗温度单一参数调节，为等离子体体基注渗工艺的优化提供了一种切实可行的研究方法。利用本文提出的工艺方法，对纯铁进行了各种温度下的N离子注渗。结果表明，处理过程中，可依据工艺设计，单参数大范围改变注渗电压或注渗恒温温度，温度波动很小，离子注入层厚度得到明显提高。     

Saturation effects observed in high fluence heavy ion implantation at few tens of keV

Effect of implantation fluence on the total number of metal atoms incorporated in a host matrix at few tens of keV beam energy has been studied experimentally using Rutherford backscattering spectrometry (RBS) as well as using simple calculations, taking Au and Ag ions for host matrices Si and silica glass. In all the cases, calculations showed that the total number of retained metal atoms are identical to the implantation fluence upto 3 × 10¹⁶ ions cm⁻² above which the metal content retained in the matrix shows a saturation. The variation in the number of metal atoms as a function of the implantation fluence extracted from the RBS measurements has been found to be in good agreement with the results of the calculation expect for the high fluence implantation case of Ag in Si. This observed difference is attributed to the irradiation induced in-diffusion of Ag atoms in Si matrix due to the low diffusion activation energy of Ag in Si. Effect of saturation on the number of metal atoms incorporated in the matrix is reflected in the Raman scattering data of the implanted Si samples as well as the optical absorption data of the implanted silica glass samples.     

Formation of a-C thin films by plasma-based ion implantation

Carbon films were prepared on a Si wafer substrate by using a plasma-based ion implantation (PBII) technique. The homogeneity of the carbon films formed on the three-dimensional object and the influence of the duty ratio of the pulse bias to the target on the property of the carbon films were investigated. The homogeneity of the carbon films formed on a convex face and that formed on a concave face by the incidence of the microwave to the target with a low angle of about −30° was almost a constant. The application of the ECR plasma source, with a mirror field, to the PBII system was efficient enough to improve the homogeneity, even though the plasma density was not very high. Diamond-like carbon films with a flat surface and a low friction coefficient can be formed by applying negative high-voltage pulses to a substrate with a low duty ratio of 1%.     

经钨离子束处理的H13钢的表面结构和成分研究

采用由金属蒸汽真空弧离子源(MEVVA)引出的强束流脉冲钨离子对H13钢进行了离子注入表面改性研究.注入剂量为3×1017cm-2,引出电压为48kV,平均束流为15μA*cm-2.利用卢瑟福背散射谱(RBS)测量了注入表面的成分,借助X射线衍射仪(XRD)和X射线光电子能谱仪(XPS)考察了注入表面的氧化情况及微观结构.研究发现,钨离子注入H13钢能减轻其表面铁元素的氧化;钨元素在其表面的原子百分比可达28%左右,并根据能带论确定了注入样品中钨和铁元素的电子结构.     

Formation of a-C thin films by plasma-based ion implantation

Carbon films were prepared on a Si wafer substrate by using a plasma-based ion implantation (PBII) technique. The homogeneity of the carbon films formed on the three-dimensional object and the influence of the duty ratio of the pulse bias tothe target on the property of the carbon films were investigated. The homogeneity of the carbon films formed on a convex face and that formed on a concave face by the incidence of the microwave to the target with a low angle of about — 30° wasalmost a constant. The application of the ECR plasma source, with a mirror field, to the PBII system was efficient enoughtoimprove the homogeneity, even though the plasma density was not very high. Diamond-like carbon films with a flat surface and a low friction coefficient can be formed by applying negative high-voltage pulses to a substrate with a low duty ratio of 1%.     

Optical investigation of nitrogen ion implanted bulk ZnO

Nitrogen ions were implanted into melt-grown ZnO (0001) substrates and subsequently annealed at 800 °C under an oxygen ambient. The photoluminescence spectrum of N⁺-implanted ZnO excited by a He-Cd laser exhibited donor-acceptor pair (DAP) transition emission at 385 nm with a full width at half maximum of 30 nm at 10 K. The DAP emission is associated with the acceptor energy of nitrogen in ZnO, calculated to be 170 meV. Defect-related red emission at about 610 nm observed in N⁺-implanted ZnO was due to the residual damage from the implantation step because it was also observed in Ar⁺-implanted ZnO but not in un-implanted ZnO annealed at 800 °C under the same oxygen ambient.     

铝型材挤压模具离子注入表面强化

铝型材热挤压模具的磨损、润滑和使用寿命短等问题直接影响着铝加工行业中铝产品的质量和厂家的经济效益。我院与广东兴发铝型材厂合作，将离子注入技术应用于铝型材生产，对铝型材挤压模具进行了表面改性处理。51只离子注入改性后的模具在线实验表明：模具总的中间使用寿命平均提高了140%，同时改善了铝型材的表面光洁度，减少了模具的拆卸、修整次数和降低了生产工人的劳动强度。     

Improving conversion efficiency of dye-sensitized solar cells by metal plasma ion implantation of ruthenium ions

Dye-sensitized solar cells (DSSC) are based on the concept of photosensitization of wide-band-gap mesoporous oxide semiconductors. At present, DSSC have ventured into advanced development and pilot production. Our current research emphasizes on improvements on titanium dioxide (TiO₂) photosensitivity under visible light irradiation by using metal plasma ion implantation (MPII). The anatase TiO₂ electrode was prepared via a sol-gel process and deposited onto indium-tin oxide glass substrates. Subsequently, the as-deposited TiO₂ films were subjected to MPII at 20 keV in order to incorporate ruthenium (Ru) atoms onto the TiO₂ surface layer. The Ru-implanted TiO₂ thin film possessed nanocrystalline Ru clusters of 20 nm in diameter and distributed in near surface layer of TiO₂ films. The Ru clusters showed effective in both prohibiting electron-hole recombination and generating additional Ru-O impurity levels for the TiO₂ band gap structure. A significant reduction of TiO₂ band gap energy from 3.22 to 3.11 eV was achieved, which resulted in the extension of photocatalysis of TiO₂ from UV to Vis regime. A small drop of photoelectric performance of 8% was obtained due to the incorporation of Ru atoms in the surface layer of TiO₂, a similar side effect as observed in the Fe-implanted TiO₂. However, the overall retention of the photocatalysis capability is as high as 92% when switch from UV to Vis irradiation. The improvement of the photosensitivity of TiO₂ DSSC by means of metal plasma ion implantation is promising.     

氧等离子体注入对PET亲水性及抗菌性能影响

利用氧等离子体浸没离子注入技术对聚合物材料(PET)进行表面改性后接枝有机抗菌剂赋予PET薄膜抗菌性能.试验结果表明:PET薄膜表面接枝上的抗菌剂在改性表面呈针状分布.经氧等离子体处理后的PET薄膜表面水接触角从78°降低到33°.红外光谱显示PET薄膜表面的分子结构被破坏,苯环的对位氢发生取代反应,分子链中形成了C-O亲水基团.氧等离子体的注入时间和注入电压均对抗菌持久性有重要的影响,较高的注入电压能够使PET薄膜表面获得较深的改性层,利于改性表面亲水性的保持.注入时间超过10min,电压超过-10kV的样品在空气中放置40天后的抗菌率仍能达到90%以上.     

低能C离子注入单晶硅机械和摩擦学性能

采用MEVVA源将低能量(40 keV)C离子注入单晶硅,用Raman光谱和SEM对试样进行了表征,用纳米压痕仪和球-盘式摩擦磨损试验机分别测试了试样硬度、弹性模量和摩擦因数.结果显示,低剂量下,试样硬度基本保持不变,而弹性模量增加;当C离子注入剂量为2×1016 cm-2时,样品出现明显非晶化,硬度开始下降.注样表面摩擦因数升高,这是由于C离子注入引起的表面损伤所致.     

Formation of aligned silver nanoparticles by ion implantation

Synthesis of metal nanoparticles by ion implantation has a number of advantages. Nevertheless, certain remaining difficulties must be overcome in order to optimize the characteristics of ion-implanted nanocomposites. The principle among these are the lack of control over the size distribution and position of the precipitates within the implanted layer. Two-dimensionally ordered arrangements of Ag nanoparticles are formed in Ag-implanted silica glass by post-implanted Cu ions. The spherical Ag nanoparticles are formed to align at the same deep depth in the silica. Cross-sectional transmission electron microscopy revealed that the Ag nanoparticles are a size of 35-48 nm in diameter. The evolution of nanoparticles is characterized by transmission electron microscopy.     

Mass transfer of metal ion implantation into metal targets at elevated temperatures

A mass transfer model for metal ion implantation into a metal target at elevated temperatures has been built up based on transport of ions in matter and radiation enhanced diffusion. It is used to calculate concentration-depth profiles and compositional changes of the implanted species. The ion implantation at elevated temperatures was simulated by a dynamic Monte Carlo (MC) method, which takes into account a local saturation in the crystalline target by using a maximum atomic fraction allowed in the matrix. For the diffusion process, the transport of the implanted species was obtained from the diffusion equations for the implanted species and nonequilibrium vacancies. The radiation enhanced diffusion coefficient was obtained by taking into account linear annealing of the defects. A nonequilibrium vacancy source function and surface sputtering were introduced into the diffusion equations. Concentration-depth profiles of Cr, Fe and Ni ions implanted into Al at a temperature range from 200 to 510 °C were calculated. The calculated results principally were consistent with measured concentration-depth profiles obtained by Rutherford backscattering spectroscopy (RBS). In some cases deviations occur, which are discussed.     

Study of deuterium metal interaction by ion implantation

Dynamic and non-equilibrium effects involving interaction between deuterium and radiation produced defects were studied during deuterium implantation of Cu and Ti. The technique of neutron yield measurement during deuterium implantation was employed and theoretical analysis was made to study the dynamics. SIMS, GIXRD and SEM studies on deuterium implanted samples were employed to study the evolution of implanted deuterium profiles, structure of deuterides and surface topography respectively.     

Accelerator based synthesis of hydroxyapatite by MeV ion implantation

Accelerator based MeV ion implantation of Ca²⁺ and P²⁺ into the titanium substrate to form hydroxyapatite (HA) has been carried out. Calcium hydroxide was formed after heating the calcium implanted titanium in air at 80 °C for 3 h. Upon subsequent annealing for 5 min at 600 °C HA was formed on the surface. Penetration depth of the HA layer in this method is much higher as compared to keV ion implantation. By elemental analysis, Ca/P ratio of the HA was found to be 1.76 which is higher than the ideal 1.67. This higher Ca/P ratio is attributed to the higher penetration depth of the MeV technique used.     

Effects of ion implantation on the microstructure and residual stress of filter arc CrN films

Chromium nitride coatings were deposited using a hybrid physical vapor deposition (PVD) system containing a filter arc deposition (FAD) and a metal plasma ion implantation source (MPII). Exactly how surface residual stress affects film characteristics is investigated using glancing incident X-ray diffraction (GIXRD) and pole figure analyses. Compared with unimplanted CrN, implanted carbon typically increases compressive residual stress and hardness. Wear resistance was also improved by implanted carbon.     

A novel technique for fabrication of metallic structures on polyimide by selective electroless copper plating using ion implantation

The successful use of palladium ion implantation into polyimide to seed an electroless plated film of copper on the polyimide surface is reported. Polyimide (Hitachi PIX 3400) was implanted with palladium ions to doses of 1.5 × 10¹⁵ − 1.2 × 10¹⁷ ions cm⁻² using a MEVVA ion implanter. The implanted ions acted as sites for nucleation of copper film. A copper film was then deposited on implanted polyimide using a commercial electroless plating solution. The ion energy was kept low enough to facilitate a low critical ‘seed’ threshold dose that was measured to be 3.6× 10¹⁶ Pd ions cm⁻². Test patterns were made using polyimide to study the adaptability of this technique to form thick structures. Plated films were studied with optical microscopy, Rutherford Backscattering Spectrometry (RBS) and Profilometry. The adhesion of films was qualitatively assessed by a ‘scotch tape test’. The film growth (thickness) was observed to be linear with plating time. A higher implantation dose led to greater plating rates. The adhesion was found to improve with increasing dose.     

金属离子注入聚合物光电特性研究

采用MEVVA离子注入机引出的Cu和Ni离子注入聚酯薄膜，注入后的聚酯膜极大降低了聚酯膜的电阻率。注入表面紫外线和红外线吸收特性明显增强。用透射电子显微镜观察注入聚酯膜的横截面，TEM观察表明，在注入层中形成了纳米金属颗粒和富集的碳颗粒。注入层的结构的变化和新相的形成引起了聚合物表面物理和化学特性的改变，进而讨论了金属离子注入聚酯膜的改性机理。