Ion Implantation Research Articles

Inverse dynamic defect annealing in ZnO

Radiation tolerance of semiconductors depends on the dynamic defect annealing efficiency during irradiation. Consequently, it matters at what temperature one keeps the sample during irradiation, so that elevated temperatures typically result in lower remaining disorder. In the present work, we observed an opposite trend for the nitrogen ion implants into zinc oxide. Combining ion channeling technique, x-ray diffraction, and photoluminescence spectroscopy, we demonstrate that the interaction of nitrogen with radiation defects promotes an inverse dynamic annealing process, so that the increase in irradiation temperature leads to a more efficient defect formation. As a result, the residual radiation disorder is maximized at 650 °C and this state is characterized by the appearance of prominent optical signatures associated with zinc interstitials and strongly reduced strain accumulation as compared to the samples implanted at lower temperatures. However, for higher implantation temperatures, the impact of the inverse annealing decreases correlating with the surface degradation and loss of nitrogen.

Reactive oxygen species may be involved in the distinctive biological effects of different doses of 12C6+ ion beams on Arabidopsis.

Heavy ion beam is a novel approach for crop mutagenesis with the advantage of high energy transfer line density and low repair effect after injury, however, little investigation on the biological effect on plant was performed. 50 Gy irradiation significantly stimulated the growth of Arabidopsis seedlings, as indicated by an increase in root and biomass, while 200 Gy irradiation significantly inhibited the growth of seedlings, causing a visible decrease in plant growth. The Arabidopsis seeds were irradiated by 12C6+. Monte Carlo simulations were used to calculate the damage to seeds and particle trajectories by ion implantation. The seed epidermis received SEM detection and changes in its organic composition were detected using FTIR. Evidence of ROS and antioxidant systems were analyzed. RNA-seq and qPCR were used to detect changes in seedling transcript levels. Monte Carlo simulations revealed that high-dose irradiation causes various damage. Evidence of ROS and antioxidant systems implies that the emergence of phenotypes in plant cells may be associated with oxidative stress. Transcriptomic analysis of the seedlings demonstrated that 170 DEGs were present in the 50 Gy and 200 Gy groups and GO enrichment indicated that they were mainly associated with stress resistance and cell wall homeostasis. Further GO enrichment of DEGs unique to 50 Gy and 200 Gy revealed 58 50Gy-exclusive DEGs were enriched in response to oxidative stress and jasmonic acid entries, while 435 200 Gy-exclusive DEGs were enriched in relation to oxidative stress, organic cyclic compounds, and salicylic acid. This investigation advances our insight into the biological effects of heavy ion irradiation and the underlying mechanisms.

Low-Energy Ion Implantation and Deep-Mesa Si-Avalanche Photodiodes with Improved Fabrication Process.

Since the avalanche phenomenon was first found in bulk materials, avalanche photodiodes (APDs) have been exclusively investigated. Among the many devices that have been developed, silicon APDs stand out because of their low cost, performance stability, and compatibility with CMOS. However, the increasing industrial needs pose challenges for the fabrication cycle time and fabrication cost. In this work, we proposed an improved fabrication process for ultra-deep mesa-structured silicon APDs for photodetection in the visible and near-infrared wavelengths with improved performance and reduced costs. The improved process reduced the complexity through significantly reduced photolithography steps, e.g., half of the steps of the existing process. Additionally, single ion implantation was performed under low energy (lower than 30 keV) to further reduce the fabrication costs. Based on the improved ultra-concise process, a deep-mesa silicon APD with a 140 V breakdown voltage was obtained. The device exhibited a low capacitance of 500 fF, the measured rise time was 2.7 ns, and the reverse bias voltage was 55 V. Moreover, a high responsivity of 103 A/W@870 nm at 120 V was achieved, as well as a low dark current of 1 nA at punch-through voltage and a maximum gain exceeding 1000.

Breakdown Characteristics of GaN DMISFETs Fabricated via Mg, Si and N Triple Ion Implantation.

Mg-ion-implanted layers in a GaN substrate after annealing were investigated. Implanted Mg atoms precipitated along the edges of crystal defects were observed using 3D-APT. The breakdown characteristics of a GaN double-diffused vertical MISFET (DMISFET) fabricated via triple ion implantation are presented. A DMISFET with Si-ion-implanted source regions was formed in Mg-ion-implanted p-base regions, which were isolated from adjacent devices by N-ion-implanted edge termination regions. A threshold voltage of -0.5 V was obtained at a drain voltage of 0.5 V for the fabricated vertical MISFET with an estimated Mg surface concentration of 5 × 1018 cm-3. The maximum drain current and maximum transconductance in a saturation region of Vds = 100 V were 2.8 mA/mm and 0.5 mS/mm at a gate voltage of 15 V, respectively. The breakdown voltage in the off-state was 417 V. The breakdown points were determined by the boundary regions between the N- and Mg-implanted regions. By improving heat annealing methods, ion-implanted GaN DMISFETs can be a promising candidate for future high-voltage and high-power applications.

Polycaprolactone Nanofibers Functionalized by Fibronectin/Gentamicin and Implanted Silver for Enhanced Antibacterial Properties, Cell Adhesion, and Proliferation.

Novel nanomaterials used for wound healing should have many beneficial properties, including high biological and antibacterial activity. Immobilization of proteins can stimulate cell migration and viability, and implanted Ag ions provide an antimicrobial effect. However, the ion implantation method, often used to introduce a bactericidal element into the surface, can lead to the degradation of vital proteins. To analyze the surface structure of nanofibers coated with a layer of plasma COOH polymer, fibronectin/gentamicin, and implanted with Ag ions, a new X-ray photoelectron spectroscopy (XPS) fitting method is used for the first time, allowing for a quantitative assessment of surface biomolecules. The results demonstrated noticeable changes in the composition of fibronectin- and gentamicin-modified nanofibers upon the introduction of Ag ions. Approximately 60% of the surface chemistry has changed, mainly due to an increase in hydrocarbon content and the introduction of up to 0.3 at.% Ag. Despite the significant degradation of fibronectin molecules, the biological activity of Ag-implanted nanofibers remained high, which is explained by the positive effect of Ag ions inducing the generation of reactive oxygen species. The PCL nanofibers with immobilized gentamicin and implanted silver ions exhibited very significant antipathogen activity to a wide range of Gram-positive and Gram-negative strains. Thus, the results of this work not only make a significant contribution to the development of new hybrid fiber materials for wound dressings but also demonstrate the capabilities of a new XPS fitting methodology for quantitative analysis of surface-related proteins and antibiotics.

Effect of Dose Rate on Tribological Properties of 8Cr4Mo4V Subjected to Plasma Immersion Ion Implantation

The lack of service lifetime of bearings has become a bottleneck that restricts the performance of aero engines. How to solve or improve this problem is the focus of most surface engineering researchers at present. In this study, plasma immersion ion implantation was conducted; in order to enhance the ion implantation efficiency and improve the wear resistance of 8Cr4Mo4V bearing steel, the dose-rate-enhanced method was adopted during ion implantation. The surface roughness, phase constituents, elemental concentration, hardness, contact angle and wear resistance of samples after ion implantation was determined by atomic force microscopy (AFM), grazing incidence X-ray diffraction (GIXRD), elemental dispersive spectroscopy (EDS), X-ray diffraction, nanoindentation tester, universal friction and wear tester, etc. The results showed that the high-dose-rate method had a significant enhancement influence on ion implantation efficiency. At the dose rate of 2.60 × 1017 ions/cm2·h, the roughness of Ra decreases from 24.8 nm to 10.4 nm, which is decreased by 58.1% for the dose rate of 7.85 × 1017 ions/cm2·h. XRD confirmed that the implanted samples consisted of the Fe(M) and Fe2–3N phase and CrN which depends on the implantation dose rate. Meanwhile, the surface hardness was improved from 11.1 GPa to 16.9 GPa and enlarged the hardened region; more valuably, the surface state of samples via high-dose-rate implantation exhibits hydrophobicity with high roughness which is able to store debris and decrease the abrasive wear during testing; thereby, the wear resistance was greatly enhanced by high-dose-rate plasma immersion ion implantation.

Microstructures, magnetic properties and microwave absorption of ion-implanted bismuth ferrite thin films

This study investigates the properties and performance of bismuth ferrite thin films on Kapton sheets as electromagnetic (EM) wave-absorbing materials. The main techniques employed in this study involved modifying the surface geometry and using electromagnetic wave-absorbing materials as surface coatings. X-ray diffraction analysis revealed a cubic crystal structure of the bismuth ferrite thin films. The bonding analysis showed the presence of Bi–O and Fe–O functional groups at 432.26 and 519.48 cm−1, respectively. Vibrating-sample magnetometry revealed the ferromagnetic behavior of the bismuth ferrite thin film, confirming that saturation magnetization decreased with increasing sputtering time. Moreover, the calcination temperature affected the coercive field; the higher the calcination temperature, the higher the coercivity of the BiFeO3 (BFO) thin film layer. Scanning electron microscopy with energy-dispersive X-ray spectroscopy of the bismuth ferrite thin films revealed the presence of Bi, Fe, and O—evenly and homogeneously distributed on the Kapton surface. After the ion implantation process, the atomic force microscopy test results showed an increased root-mean-square roughness (Rq). The root-mean-square roughness value for Kapton before the process was approximately 7.5 nm, while the root-mean-square roughness values for BFO 10 min and BFO 12.5 min were approximately 18.8 nm and 25.3 nm, respectively. The microwave absorption ability reached a maximum reflection loss value of − 40.4 dB (99.9 %) in the range of 9.98 GHz with a sputtering duration of 10 min. Therefore, these results suggest bismuth ferrite is a potential candidate as an EM wave absorber.

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.

Improved Placement Precision of Donor Spin Qubits in Silicon using Molecule Ion Implantation

AbstractDonor spins in silicon‐28 are among the best performing qubits in the solid state, offering unmatched coherence times, gate fidelities beyond 99% and the ability to fabricate arrays using deterministic ion implantation. Donor placement precision is improved upon, advantageous for qubit readout and coupling, by implanting molecule ions that carry bystander atoms to boost the detection confidence. Here, the suitability of phosphorus difluoride () molecule ions is demonstrated to fabricate donor qubits. Using secondary ion mass spectrometry, it is confirmed that (nuclear spin ) diffuses away from the implant site while remains close to its original location during a donor activation anneal. Electron spin resonance measurements are then performed on ‐implanted qubit devices. A pure dephasing time of and a coherence time of are extracted for the P donor electron‐ values comparable to those found in conventional atomic ‐implanted qubit devices. Additionally, the P donor electron is not found to hyperfine couple to any nuclear spins in its vicinity. Molecule ions therefore show great promise for producing high‐precision deterministically‐implanted arrays of long‐lived donor spin qubits.

Fabrication of thin diamond membranes by [formula omitted] implantation

Color centers in diamond are one of the most promising tools for quantum information science. Of particular interest is the use of single-crystal diamond membranes with nanoscale-thickness as hosts for color centers. Indeed, such structures guarantee a better integration with a variety of other quantum materials or devices, which can aid the development of diamond-based quantum technologies, from nanophotonics to quantum sensing. A common approach for membrane production is what is known as “smart-cut”, a process where membranes are exfoliated from a diamond substrate after the creation of a thin sub-surface amorphous carbon layer by He+ implantation. Due to the high ion fluence required, this process can be time-consuming. In this work, we demonstrated the production of thin diamond membranes by neon implantation of diamond substrates. With the target of obtaining membranes of ∼200 nm thickness and finding the critical damage threshold, we implanted different diamonds with 300 keV Ne+ ions at different fluences. We characterized the structural properties of the implanted diamonds and the resulting membranes through SEM, Raman spectroscopy, and photoluminescence spectroscopy. We also found that a SRIM model based on a two-layer diamond/sp2-carbon target better describes ion implantation, allowing us to estimate the diamond critical damage threshold for Ne+ implantation. Compared to He+ smart-cut, the use of a heavier ion like Ne+ results in a ten-fold decrease in the ion fluence required to obtain diamond membranes and allows to obtain shallower smart-cuts, i.e. thinner membranes, at the same ion energy.

Photoluminescence enhancement from hot nitrogen-ion implanted Si quantum dots embedded within SiO2 layer

Using the novel process of hot N+-ion implantation at 800 °C into Si quantum dots (Si-QDs) with approximately 3.2 nm fabricated by hot Si+-ion implantation into an SiO2 layer and post-Ar annealing, we experimentally demonstrated that the photoluminescence intensity (IPL) of the Si-QDs increased with increasing N+-ion dose (DN+). Post-N2 high-temperature annealing without hot N+-ion implantation, as a reference process, also increased the IPL of Si-QDs, because N atoms trapped within Si-QDs, which was evaluated by secondary ion mass spectrometry, terminate the dangling bonds within Si-QDs and at the Si/SiO2 interface. Additionally, the IPL of Si-QDs showed the maximum value at the optimal DN+ of 5 × 1015 cm−2, which was 1.4-fold higher than that observed without hot N+-ion implantation. With a short post-annealing time (<60 min), the increase in IPL owing to N+-ion implantation was considerably larger than that caused by N2 annealing, which is likely due to the efficiency of the termination of the dangling bonds of the Si-QDs by the N+-ions. This is an advantage of the hot N+-ion implantation technique. Forming gas annealing after furnace annealing also induced a larger IPL than that observed before forming gas annealing. However, the maximum IPL observed after forming gas annealing was completely independent of the conditions of furnace annealing and DN+. This suggests that the perfect termination of the dangling bonds of the Si-QDs may be realized via forming gas annealing after furnace annealing.

Generalized damage profile function for subsurface damage in SiC induced by helium focused ion beam under line scanning at different energies and doses

Silicon carbide is receiving increasing attention as a substrate due to its stability in harsh environments. At the same time, further minimization of sensors and micro devices requires new techniques for nanofabrication. In this context, the helium focused ion beam (He-FIB) is a promising candidate, due to its high resolution and capability of sub-10 nm fabrication, as well as its ability to modify the properties of the substrate via ion implantation. In this work, we consider previously reported experimental images of subsurface damage in both SiC and Si, as induced by He-FIB under line scanning, and provide a summary of the resulting amorphous and bubble regions as a function of the beam energy and dose. Based on empirical relations collectively encapsulated into a damage profile function (DPF) that was previously used to describe the contour of the amorphous region in Si, we focus on presenting a generalized damage profile function (GDPF) that enables describing the contours of both the amorphous and bubble regions in SiC simultaneously. In particular, the role of swelling, as a relatively small protruding region from the initial surface that eventually restricts the upward expansion of the bubble region, is fully considered. The parameters of the resulting mathematical model are related to measurements from the experimental cross-sectional images and are eventually optimized by using an evolutionary algorithm. Comparison to the experimental profiles concludes that the proposed GDPF captures both the amorphous and bubble region profiles with good precision.

Enhancing damping-like efficiency by low-energy mixed ions bombardment

Pursuing enhanced spin–orbit torque (SOT) has become a significant focus for achieving energy-efficient spintronics devices. Researchers have explored different materials, layer engineering, and various post-deposition modification methods to realize higher SOT. Here, we have utilized the bombardment of mixed ions (Ar+ and He+ in various ratios) with 0.6 kV bias voltage to enhance the SOT efficiency in a Pt/Co/W stack. The bombardment modifies the physical properties (magnetic, electric, and structural) due to cascade collision, knocking off atoms (from the surface), and ion implantation. The increased percentage of He+ suppresses the drastic behavior of cascade collisions, and hence, the properties are tunable by changing the gas ratio. We exploited this behavior to design a material stack with enhanced SOT efficiency. We fabricated Hall bars to quantify SOT and observed a 4.5× increase in the effective damping-like efficiency. The efficiency and switching current density in the stack could be tuned by the variation of Ar:He ion ratio and the exposure duration. This study offers an easy route to tune the energy efficiency of spin devices, contributing to the advancement of next-generation spintronics.

Microstructural evolution and tribological properties of TC6 titanium alloy strengthened by laser peening combined with nitrogen ion implantation

To obtain a combined strengthening layer and further redouble the ability to resist wear of TC6 titanium alloy, an innovative technique of laser peening plus nitrogen ion implantation was proposed. The tribological properties of the specimen subjected to combined laser peening and nitrogen ion implantation were analyzed using transmission electron microscope, nanoindentation tester, sliding friction wear tester and scanning electron microscopy. The results showed that laser peening combined with nitrogen ion implantation induced a higher density of dislocation than that produced only by laser peening or nitrogen ion implantation. Compared with the ion implanted and laser peened samples, the surface nano-hardness subjected to combined strengthening process was increased by 21.3 % and 5.8 %. Moreover, the friction coefficient of combined processed specimen reduced to 0.4, the wear tracks depth and width were about 19.02 μm and 300 μm, while the wear mechanism was mainly abrasive and oxidative wear. The dislocations, sub-grains and mechanical twins produced by laser peening provided large amounts of diffusion channels for ion implantation, which conferred better wear resistance than the samples processed only by laser peening or nitrogen ion implantation.

Low-temperature process design for inversion mode n-channel thin-film-transistor on polycrystalline Ge formed by solid-phase crystallization

We fabricated an inversion mode n-channel thin-film-transistor (TFT) on polycrystalline (poly-) Ge at low temperatures for monolithic three-dimensional large-scale IC (3D-LSI) and flexible electronics applications. Based on our previously reported solid-phase crystallization (SPC) method, we designed an n-channel TFT fabrication process with phosphorous ion implantation to provide the source/drain (S/D). We succeeded in fabricating an n-channel TFT with typical electrical characteristics on poly-Ge and confirmed its operation mode to be inversion mode. However, the fabrication process included a high temperature (500 °C) step for S/D activation. To reduce the process temperature, we used a metal-induced dopant activation method and successfully reduced the activation temperature to 360 °C. This combination is expected to pave the way for high-performance 3D-LSI and flexible electronic devices based on SPC-Ge.

Green to deep-red emissive carbon dot formation by C+ ion implantation on nitrogen beam created self-masked nano-template

We report the formation of green to red emissive arrays of carbon dot on silicon-nitride nano-templates by successive implantation of nitrogen and carbon broad ion beams. The patterned nano-templates are formed by 14 keV N2 + ion-bombardment at grazing incident (70°) on Si. Subsequently, 5 keV C+ ions are implanted at the selective sites of the pyramidal nano-template by taking advantage of the self-masking effect. The nano-pyramidal pattern and the implanted carbon dots at the specific sites are confirmed by atomic force microscopy and cross sectional transmission electron microscopy measurements. The developed carbon dots (CDs) are mostly amorphous and consists of SiC and graphitic nitrogen (CN). G-band and D-band carbons are identified by Raman spectroscopy, while the presence of SiC and CN are detected by XPS measurements. A change of band-gap is observed for C-implanted templates by the UV–vis spectroscopy. Excitation wavelength-dependent photoemission from the dots is found in the green to red region. Maximum intense PL is observed in the green–orange region for excitation wavelength of 425 nm and a redshift of PL with decreasing intensity is observed with the increase of excitation wavelength. The observed photoluminescence is described in terms of the combined effects of quantum confinement, graphitic nitrogen and defect induced additional states formation in the carbon dots. The potential applications of CDs are also addressed.

Silicon nitride resistance switching MIS cells doped with silicon atoms

Stoichiometric SiNx layers (x = [N]/[Si] = 1.33) are doped with Si atoms by ultra-low energy ion implantation (ULE-II) and subsequently annealed at different temperatures in inert ambient conditions. Detailed material and memory cells characterization is performed to investigate the effect of Si dopants on the switching properties and performance of the fabricated resistive memory cells. In this context extensive dc current–voltage and impedance spectroscopy measurements are carried out systematically and the role of doping in dielectric properties of the nitride films is enlightened. The dc and ac conduction mechanisms are investigated in a comprehensive way. Room temperature retention characteristics of resistive states are also presented.

Ion implantation induced nucleation and epitaxial growth of high-quality AlN

AlN materials have a wide range of applications in the fields of optoelectronic, power electronic, and radio frequency. However, the significant lattice mismatch and thermal mismatch between heteroepitaxial AlN and its substrate lead to a high threading dislocation (TD) density, thereby degrading the performance of device. In this work, we introduce a novel, cost-effective, and stable approach to epitaxially growing AlN. We inject different doses of nitrogen ions into nano patterned sapphire substrates, and then deposit the AlN layers by using metal-organic chemical vapor deposition. Ultraviolet light-emitting diode (UV-LED) with a luminescence wavelength of 395 nm is fabricated on it, and the optoelectronic properties are evaluated. Compared with the sample prepared by the traditional method, the sample injected with N ions at a dose of 1×10<sup>13</sup> cm<sup>–2</sup> exhibits an 82% reduction in screw TD density, the lowest surface roughness, and a 52% increase in photoluminescence intensity. It can be seen that appropriate dose of N ion implantation can promote the lateral growth and merging process in AlN heteroepitaxy. This is due to the fact that the process of implantation of N ions can suppress the tilt and twist of the nucleation islands, effectively reducing the density of TDs in AlN. Furthermore, in comparison with the controlled LED, the LED prepared on the high quality AlN template increases 63.8% and 61.7% in light output power and wall plug efficiency, respectively. The observed enhancement in device performance is attributed to the TD density of the epitaxial layer decreasing, which effectively reduces the nonradiative recombination centers. In summary, this study indicates that the ion implantation can significantly improve the quality of epitaxial AlN, thereby facilitating the development of high-performance AlN-based UV-LEDs.

Preparation of damage-free kerogen specimen for microscopy: Understanding the damage mechanisms induced by ion milling techniques

Focused ion beam (FIB) milling techniques have been used for more than a decade to prepare organic-rich shale samples for electron microscopy. Nano- and micro-scale imaging of organic pores is used to assess pore volumes and hence estimate gas-in-place. Ion milling natural composites is particularly challenging due to drastic extremes in the physical properties of individual phases such as minerals and organics. Damage to the organic-rich phases occurs due to the large differences in thermal conductivities of minerals and organics that could reach an order of magnitude and the resulting buildup of heat in the organics. Furthermore, radiation damage via ion implantation may also alter the structural characteristics of the shale.Herein, the damage associated with preparing electron-transparent kerogen specimen using low kV FIB, cryo-FIB, and cryomicrotome, a new technique for shale kerogen, is quantified using experimental and modeling techniques. The degree of gallium implantation is quantified using scanning transmission electron microscopy (STEM), selected area electron diffraction (SAED), and energy dispersive X-ray spectroscopy (EDX) along with the stopping range of ions in matter (SRIM) model. Interestingly, although the use of cryogenic temperature removes the thermal effect, Ga+ ion implantation is observed in the specimen prepared by cryo-FIB.Furthermore, the magnitude of the thermal damage at a highly localized level was determined using nano-beam electron diffraction (NBED) performed at −196 °C. Time-resolved diffraction patterns indicate that despite the fact kerogen is among the most stable geopolymers, the aromatic components still degraded due to the local temperature increases. On the other hand, the cryomicrotome technique operating at liquid nitrogen temperature is demonstrated as a suitable method to prepare thin kerogen specimen while minimizing structural damage and preserving its native porosity and chemical composition.

Kinetics of Stainless Steel Material by Plasma nitriding Process for sustainable applications

Implantation of ion at low temperature and nitriding through plasma process at low-temperature prevents the corrosion resistance in stainless steel material. The outcome of nitriding process is to form precipitation of CrN on the surface. For the current research work, plasma nitriding techniques are adopted to nitride AISI 304 at low-temperatures at 5hrs, 10hrs, 15 hrs. The enriched layers are formed with combine nitrogen lead to increase in surface hardness. Austenitic and duplex steels produce expanded austenite on the material surface. Behavior of wear was monitored by pin on disc tester. The case depth were monitored and compared with a sample which is not treated. The morphology of surface were monitored and compared with the electron microscopic images. Finally hardness measurements were carried out with Rockwell hardness tester.