Metal Plasma Immersion Ion Implantation And Deposition Research Articles

Properties of TiAlN coating deposited by MPIIID on TiN substrates

Metal plasma immersion ion implantation and deposition (MPIIID) is employed to produce TiAlN hard coatings on Ti substrate. To improve the load-bearing capacity of Ti substrate, nitrogen PIII is used to prepare a bearing TiN layer on Ti-base substrate. The MPIIID process is performed using Ti50:Al50 target for different nitrogen/argon gas fractions. The effect of N2/Ar gas ratio on the microstructure, mechanical and tribological properties of TiAlN coatings has been studied. The plastic microhardness of TiAlN increases with increasing the nitrogen gas fraction to reach a maximum value of 30 GPa at 100 % N2. The plasticity index and the resistance to plastic deformation increase with increasing the nitrogen gas fraction. The wear volume loss of TiAlN coating deposited on TiN substrate decreases by a factor of 103 in comparison with pure Ti. Moreover, the friction coefficient decreases from nearly 0.8 for Ti to 0.25 for TiAlN coatings. The enhanced mechanical and tribological properties of the coating are correlated with the formation of TiAlN hard phase. This phase has random-oriented microstructure, finer grain size, high oxidation resistance and residual internal stress. Moreover, the TiN interface acts as a barrier for the motion of dislocations.

Surface modification of biomaterials by metal plasma immersion ion implantation and deposition (MPIIID)

Event Abstract Back to Event Surface modification of biomaterials by metal plasma immersion ion implantation and deposition (MPIIID) Huiliang Cao1* and Xuanyong Liu1* 1 Shanghai Institute of Ceramics, Chinese Academy of Sciences, State Key Laboratory of High Performance Ceramics and Superfine Microstructure, China Introduction: Surface modification of biomaterials with balanced biological properties, i.e. inhibit the adhesion of pathogenic bacteria but promote the positive functions of bone cells, is highly desired for orthopedic and dental implants. Ion implantation, capable of forming new phases or alloys beyond the normal thermodynamic constraints[1], will facilitate realizing such designs in surface modifications. During the past years, by using the cathodic-arc-sourced metal plasma immersion ion implantation and deposition (MPIIID) technique, our group published more than 20 articles concerning improving the biological performance of various biomaterials[2]-[5]. Materials and Methods: MPIIID was applied to introduce silver and titanium onto titanium oxide and polyetheretherketone (PEEK) substrates, respectively. The physical and chemical characteristics of the MPIIID-treated materials were studied by various techniques, including transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The in vitro responses of both bacterial and mammalian cells were evaluated by using S. aureus (or E. coli) and bone marrow stem cells (BMSCs). The in vivo responses of bone tissues were revealed by bone defect and osteomyelitis models in rats. Results and Discussion: The results demonstrated that the precipitation behavior of silver nanoparticles (Ag NPs) on titanium oxide (Figure 1) can be tailored by manipulating the atomic-scale heating effect in MPIIID, and a nano-porous layer can be constructed on PEEK (Figure 2) by taking advantage of the charging effect of MPIIID. So that good antimicrobial activity and/or excellent osteogenic property were evidenced on these MPIIID-treated materials. Conclusion: Since developing of tactics that inhibit bacterial colonization as well as promote osseointegration is of great significance in clinic, MPIIID will be served as high impact technique for processing of orthopaedic and dental devices with better performances. Figure 1 Silver nanoparticles (Ag NPs) with various size and distribution were fabricated on titanium oxide coatings by using silver plasma immersion ion implantation (Ag-PIII)[2]. Figure 2 The nano-porous layer fabricated on carbon-fiber-reinforced polyetheretherketone (PEEK) by using titanium plasma immersion ion implantation (Ti-PIII)[5]. This work is supported by the National Basic Research Program of China (973 Program, 2012CB933600), National Natural Science Foundation of China (31370962), Shanghai Committee of Science and Technology, China (14XD1403900), Shanghai Rising-Star Program (15QA1404100), Youth Innovation Promotion Association CAS (2015204), the Open Research Fund of State Key Laboratory of Bioelectronics, Southeast University.

Properties of aluminum oxide thin film obtained by metal plasma immersion ion implantation and deposition after zirconium-based pretreatment

Aluminum oxide thin films were obtained by metal plasma immersion ion implantation and deposition (MePIIID) and subsequently converted by a zirconium based surface pretreatment. Thin films atomic composition was studied using Rutherford backscattering spectrometry (RBS) and forward recoil spectrometry (FRS), especially for hydrogen measurement. Film morphology and thickness were investigated by atomic force microscopy (AFM) and field emission scanning electron microscopy (FE-SEM). Wettability was assessed by contact angle measurements. The corrosion behavior was investigated using EIS measurements and potentiodynamic polarization curves. Results pointed out to the deposition of a highly oxidized film with high hydrogen content with smooth surface. After conversion, wettability was greatly enhanced as denoted by the 50% decrease of the contact angle after conversion. The conversion treatment decreased the values of icorr from 1.51 to 0.75 μA cm−2. Excellent corrosion resistance was achieved when an acrylic coating was applied over the converted MePIIID layer, further decreasing icorr to 0.004 μA cm−2.

Metal plasma immersion ion implantation and deposition (MePIIID) on screw-shaped titanium implant: The effects of ion source, ion dose and acceleration voltage on surface chemistry and morphology

The present study investigated the effect of metal plasma immersion ion implantation and deposition (MePIIID) process parameters, i.e., plasma sources of magnesium and calcium, ion dose, and acceleration voltage on the surface chemistry and morphology of screw-type titanium implants that have been most widely used for osseointegrated implants. It is found that irrespective of plasma ion source, surface topography and roughness showed no differences at the nanometer level; that atom concentrations increased with ion dose but decreased with acceleration voltage. Data obtained from X-ray photoelectron spectroscopy and auger electron spectroscopy suggested that MePIIID process produces ‘intermixed’ layer of cathodic arc deposition and plasma immersion ion implantation. The MePIIID process may create desired bioactive surface chemistry of dental and orthopaedic implants by tailoring ion and plasma sources and thus enable investigations of the effect of the surface chemistry on bone response.

A new algorithm for charge deposition for multiple-grid method for PIC simulations in r– z cylindrical coordinates

A mesh of nodes used in particle-in-cell simulations may be refined in some regions to obtain better local spatial resolution without adding excessive computational cost. Each refinement can be seen as a finer grid in a multiple-grid system. The standard bilinear weighting method in two-dimensional ( r– z) cylindrical coordinates using a multiple-grid system is detailed and an inadequacy in the method is presented. A new algorithm of particle to node weighting in a multiple-grid system is then described and compared to the standard bilinear weighting method in two-dimensional ( r– z) cylindrical coordinates. This description pays particular attention to the nodes near the interface between grids of differing cell-size. The volume weighting method used in this study is geometrically similar to the standard bilinear PIC method in Cartesian coordinates, but weights in proportion to the volumes of revolution of the areas about the z-axis, rather than the areas themselves. As the volume weighting method has the axisymmetric geometry built in, it is a natural system to use in this particular case. A full particle-in-cell (PIC) simulation of metal plasma-immersion ion implantation and deposition (MePIIID) of a flat stage using three grids of cell size: 0.5 × 0.5, 1 × 1 and 2 × 2 mm; is performed and results are compared to those obtained from a single-grid simulation with the same parameters. The multiple grid method compares very well to the single-grid simulation.

Hemocompatibility of titanium-based coatings prepared by metal plasma immersion ion implantation and deposition

Metal plasma immersion ion implantation and deposition (MePIIID) has been proved to be an effective approach to enhance surface properties of various types of materials. In this work structure, phase composition, microhardness and surface properties, such as wettability and surface energy of layers of the ternary system Ti–N–O produced by MePIIID were investigated. To study the correlation between structure of coating and hemocompatibility the thrombocyte adhesion as well as the fibrinogen adsorption on the surface were measured. The blood compatibility of Ti oxide can be improved by the addition of nitrogen into the layer. The thrombocyte adhesion and fibrinogen adsorption were lower for TiNxOy than for TiO2. This correlates with a lower hydrophobicity and higher polar component of the surface energy for TiNxOy. The best hemocompatibility as well as the maximal microhardness have been found for the coating TiN0.4O1.6.

Numerical Simulation of Metal Plasma Immersion Ion Implantation (MePIIID) on a Sharp Cone and a Fine Tip by a Multiple-Grid Particle-in-Cell (PIC) Method

A multiple-grid particle-in-cell (PIC) method in r-z cylindrical coordinates is developed to study metal plasma immersion ion implantation and deposition (MePIIID) of a sharp cone with a fine tip. At the boundary between the coarse and fine grids, the cells are subdivided into smaller regions so that the effective volume of each node does not overlap with each other when calculating the ion density from PIC weighting. In a previous paper, the ion dose, which is defined as the accumulated implanted ions per area, showed a sharp decrease near the cone tip [Cornet J. Appl. Phys., vol. 96, p. 6045, 2004]. However, the tip of the cone was described by only one single point. By applying a multiple-grid method to numerically simulate the MePIIID on a sharp cone with a fine tip, it is revealed that the highest dose is located at the center of the tip, and it is concluded that the sharp decrease in dose in a previous paper is an artifact of the single point. A multiple-grid system with three different cell sizes, i.e., 2, 1, and 0.5 mm, is used in the simulation. The tip of the cone is represented by a sphere in tangential contact with the edge of the cone

Formation of transparent ZnO layers by MePIIID

ZnO thin films were deposited using metal plasma immersion ion implantation and deposition (MePIIID) with high voltage pulses from 0 to 10kV at a duty cycle of 9%. All films exhibit a (002) fibre texture of the hexagonal ZnO phase. With increasing bias voltage, an increased sub-band gap absorption was observed with spectroscopic ellipsometry, together with preferential sputtering of oxygen from the film. Only a partial reversal of this effect was obtained with an increased oxygen/zinc ratio on the supply side showing that additional radiation induced defects are present in the film at high pulse voltages.

Correlation between RBS, reflectometry and ellipsometry data for TiO2 films deposited on Si

Using metal plasma immersion ion implantation and deposition (MePIIID) it is possible to obtain highly textured rutile layers within a wide range of stoichiometry, depending on the oxygen gas flow to titanium arc current ratio, on silicon. Even for a composition of TiO1.8, only rutile reflections were found with X-ray diffraction. Reflectometry spectra show an internal structure of two layers with a similar density. At the same time, the layer thickness obtained from spectroscopic ellipsometry is considerable less than that from Rutherford backscattering spectroscopy (RBS), indicating that a rather abrupt transition from metallic to semiconducting is observed within the films, depending on the process conditions.

Correlation between blood compatibility and physical surface properties of titanium-based coatings

Layers of Ti nitride, Ti oxynitrides TiNxOy and Ti oxide were produced by means of metal plasma immersion ion implantation and deposition (MePIIID) from a plasma produced by cathodic arc evaporation of Ti under addition of nitrogen and/or oxygen to the ambient near the substrate. The phase composition and structure of the layers are strongly dependent on the relation of the gases partial pressure. To study the correlation between blood compatibility and physical properties of the coating the thrombocyte adhesion and fibrinogen adsorption on the surface as well as wettability and surface energy were investigated. Thrombocyte adhesion and fibrinogen adsorption are lower for TiNxOy than for TiO2. This correlates with a lower hydrophobicity and higher polar component of the surface energy for TiNxOy.

Two-dimensional texture and sheath evolution in metal plasma immersion ion implantation

The spatial texture evolution and variation across a sample holder (6 cm diameter) was investigated for titanium nitride thin films deposited by metal plasma immersion ion implantation and deposition (MePIIID). With increasing pulse voltage from −1 to −10 kV and increasing pulse frequency, a transition of the texture from [111] via [220] to [200] was observed. Here, the product of pulse frequency and voltage is determining the texture, with the slight dependence of the fluence per pulse on the voltage as a minor correction. Near the edge of the samples, a tilt of the crystallites was observed. For high frequencies, an equilibrium position was observed, while a gradual decrease of the tilt with lower frequencies is present. Apparently, the orientation of the grains along the ion incidence direction is a dynamic process requiring a certain minimum energy input for a complete transformation.

Disorder formation in rutile during ion assisted deposition

Ion assisted deposition (IAD) is a well-known method for obtaining dense and well adhering surface layers. Conventional IAD operates with evaporated metal atoms and energetic gaseous ions whereas metal plasma immersion ion implantation and deposition (MePIIID) draws energetic metallic ions from a cathodic arc which may additionally ionise the background gas. TiO 2 is a widely investigated material for biomedical, optical and catalysis applications. MePIIID is employed to deposit TiO 2 films onto Si substrates at different pulse voltages up to 10 kV. X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies are performed to investigate the changing film properties as a function of pulse voltage and to estimate the barrier efficiency against diffusion through the layer.

Young Modulus Measurement of Nanostructured Metallic Thin Films

Keyword : thin films, Young modulus, nanostructures Abstract. We have uniformly coated cantilever of an Atomic Force Microscope (AFM) with metallic thin films. These films are deposited with a system of Metal Plasma Immersion Ion Implantation and Deposition (MePIIID). The metals used for deposition were gold, platinum and palladium. These films are nanostructured with thickness going from 18 up to 111 nm. We have determined the Young modulus of the metallic thin films (E 2). The E 2 values for gold, platinum and palladium are: 69,1 ± 2.6 GPa, 139.7 ± 2.7 GPa and 115.1 ± 2.1 GPa, that are about 12%, 12% and 7 % lower than the respective bulk elastic modulus.

Transparent AlN layers formed by metal plasma immersion ion implantation and deposition

Aluminum nitride is a very attractive semiconductor material, suitable for UV optoelectronics due to its large band gap. The influence of the ion bombardment during energetic deposition with metal plasma immersion ion implantation and deposition (MePIIID) on the defect structure and hence the optical properties is investigated for a pulse voltage between 0 and 5 kV at a duty cycle of 9%. With increasing voltage, anti-site defects are decreasing. However, secondary effects as increased oxygen adsorption and oxygen complex formation suggest that the simultaneous heating of the sample by the incoming ions is responsible for this effect and ions even at 5 keV might produce more damage than they remove.

The study of composition, structure, mechanical properties and platelet adhesion of Ti–O/TiN gradient films prepared by metal plasma immersion ion implantation and deposition

Titanium oxide and titanium nitrogen gradient films were prepared by three different processes using metal plasma immersion ion implantation and deposition (MPIII-D). The mechanical properties of the films synthesized on silicon wafers, Ti6A14V and low temperature isotropic carbon (LTIC) were evaluated by nano-indentation, pin-on-disc wear, and scratching test. The hardness of the film was measured to be 19.5 GPa. Investigation by XRD shows that the surface Ti–O layer possesses a rutile structure and analysis by X-ray photoelectron spectra (XPS) discloses that the surface composition of the synthesized TiN/Ti–O films is non-stoichiometric. The gradient characteristics of the films were corroborated by qualitative analysis of secondary ion mass spectroscopy (SIMS). The thickness of films was 510–940 nm. Platelet adhesion experiments adopted to estimate the blood compatibility of the films show that the adsorption and deformation of platelets on the synthesized TiN/Ti–O gradient films have been significantly suppressed compared to LTIC. Scanning electron microscopy (SEM) used to assess the wear and scratch tracks discloses that the films exhibit good wear resistance and high adhesion strength.

Plasma stream homogeneity in metal plasma immersion ion implantation and deposition

The homogeneity of metal plasma immersion ion implantation and deposition (MePIIID) was investigated for flat substrates and the materials systems Al, AlN, Ti, TiN, TiO/sub 2/, and ZnO. A shield was installed in the line-of-sight between the cathode and substrates (diameter 60 and 100 mm) to reduce macroparticle counts. An influence of pulse voltage, cathode material, and backfill on the lateral homogeneity was observed so the plasma stream emanating from the arc as well as the plasma sheath evolving around the substrates contributed to the radial homogeneity in MePIIID. The major factor was the ratio of the sheath width to the sample diameter, with additional influences from the ion velocity and mean free path. For small, conformal sheaths, a normal ion incidence was observed for the substrate, whereas larger, spherical sheaths resulted in oblique ion trajectories near the edge, with an increased sputter yield and lower dose.

Interplay of surface adsorption and preferential sputtering in metal plasma immersion ion implantation and deposition

Formation of hard ceramic surface layer by metal plasma immersion ion implantation and deposition (MePIIID) can be a quite complex process as quite a number of different species, including condensable metallic ions, electrons and neutral gas, which can be partially ionised, are interacting in the vacuum chamber and impinging on the surface. The resulting growth rate and chemical composition will be determined by the complex interplay of surface adsorption, ion implantation and preferential sputtering. Here, an overview of these effects is given for the important systems ZnO, TiO 2, TiN and AlN prepared by MePIIID. In ZnO, the predominant mechanism is preferential oxygen sputtering. However, the oxygen adsorption from the background gas is stronger in the case of TiO 2, leading to a constant Ti/O ratio beyond a threshold in the oxygen gas flow for this compound. This effect is less pronounced for TiN, where a continuously varying Ti/N ratio was found only for a varying gas flow and independent of the pulse voltage. In contrast, a constant Al/N ratio over a broad range of nitrogen gas flows was observed for AlN.

Homogeneity of metal plasma immersion ion implantation and deposition

Metal plasma immersion ion implantation and deposition (MePIIID) is a method, where metallic ions emanating from a cathodic arc are deposited onto a sample, intermittently pulsed to negative high voltage pulses. Thus, a fast coating of three-dimensional samples with excellent adhesion properties is possible at low temperatures. Albeit, the homogeneity and the ion incident angle are strongly dependent on the process conditions, i.e. cathode material, gas backfill, sample size and pulse voltage. Corresponding experiments for AlN, TiN, Ti and Al using pulse voltages of up to 10 kV and different flat sample holders are presented. In the discussion, an attempt to assess the relative importance of the process parameters is made.

Lateral homogeneity variation in metal plasma immersion ion implantation and deposition

Using a cathodic arc, with a shield to reduce the droplet rate, it is possible to obtain homogeneous AlN films across substrates with diameters up to 10 cm by metal plasma immersion ion implantation and deposition (MePIIID). The film thickness varies by less than 5%, as measured by spectroscopic ellipsometry. For a sample with a diameter of 10 cm no major influence of the voltage on the thickness homogeneity was observed. However, for a sample with a diameter of 6 cm and the same deposition conditions the thickness at the edge decreased by more than 33 and 50% for pulse voltages of 5 and 10 kV, respectively. Thus, the geometry of the shield and the sample holder can have a strong influence on the direction of the plasma stream emanating from the cathodic arc. Additionally, the working pressure and plasma composition plays a major role in determining the homogeneity, as was observed using Al and Ti cathodes without background gas or with nitrogen.

In situ diffusion measurements during RBS analysis of polymers coated with aluminium

Using metal plasma immersion ion implantation and deposition (MePIIID), it is possible to form dense metallic layers with excellent adhesion properties at low temperatures, for example on polymers. Rutherford backscattering spectroscopy is one method to determine the thickness of the layer and the interface: albeit, the polymer is destroyed by the high energy ions and gaseous products can diffuse out. For this study, an Al layer is used as a diffusion barrier, trapping fluorine at the interface between the polymer and the metallisation. The barrier efficiency is investigated as a function of layer thickness and pulse voltage during MePIIID.