Unbalanced Magnetron Sputtering System Research Articles

Application of honeycomb pattern to Ti2AlN MAX phase films by plasma etching

The honeycomb pattern possesses a distinctive hexagonal structure capable of seamless repetition on a flat surface, leaving no gaps. Moreover, all arm thicknesses and angles are equal to one another. This remarkable configuration is deemed biomimetic, with numerous examples found in nature. Notably, it exhibits remarkably low density and exceptional mechanical strength. MAX phase films have gathered significant attention due to their exceptional capacity to amalgamate the essential properties of both metals and ceramics. Additionally, they possess the unique ability to effectively mend surface cracks that may arise as a result of friction-wear, restoring the material to a certain degree of integrity. In this study, Ti2AlN MAX phase thin films were deposited on M2 steel substrates by a closed field unbalanced magnetron sputtering system (CFUBMS). 750 °C heat treatment was applied to obtain the produced films in crystalline form. In addition, plasma etching parameters suitable for the phase structure of the deposited film were determined. With the inductive coupling plasma etching (ICP) process, the honeycomb pattern was given to the Ti2AlN MAX phase films with a continuous and smooth geometry at a depth of 2 μm. This study gives ideas for the development of multi-coating systems in which patterns of different geometries are included in a single layer.

Effect of substrate bias on the formation of nanotwin and properties in Cu thin films for advanced packaging technology

Materials with nanotwinned structures have drawn much attention due to their unique properties. The high-density nanotwinned Cu films are generally deposited at room temperature with high deposition rate. In this study, we report nanotwins can be formed in the Cu films at 150 °C with the aid of the ion bombardment effect caused by applied substrate bias. Cu thin films were deposited on Si (100) substrate by the unbalanced magnetron sputtering system using different applied substrate biases ranging from 0 V to −160 V. The results show that, with a suitable applied substrate bias of −120 V, the twinning density of the Cu films can reach over 80 % and exhibit a high hardness of 3.1 GPa. This study provides a concept to tailor the microstructure of the sputtered Cu films by tuning applied substrate biases and realizing the mechanism of substrate bias on the twin formation during deposition.

Pulsed-dc bias magnetron sputtered TiB2 ceramic coating

Titanium diboride, TiB2, is well known as a ceramic material with a hexagonal structure which presents various attractive properties, such as high hardness and excellent corrosion, thermal oxidation, and wear resistance. However, one drawback of TiB2 coatings is their poor adhesion to substrate materials due to high compressive residual stress after deposition. The present study aimed to assess whether a PVD-TiB2 coating with both high hardness and sufficiently good adhesion to the substrate and good wear properties can be developed by a closed-field unbalanced magnetron sputtering system using pulsed-dc biasing. The TiB2 coating deposited on AISI M2 steel substrates was characterized in terms of the structural, mechanical and tribological property. From the experimental results, it can be concluded that a closed-field unbalanced magnetron sputtering system using pulsed-dc biasing can be used to produce a TiB2 coating with sufficiently good adhesion (82 N), and high hardness (2300 HK0.01), and low friction (0.34) under given deposition conditions. The deposition conditions, particularly substrate biasing and rotation, which inhibited the formation of (001) orientation, played a role in the coating's lack of superhardness.

High-temperature tribological behavior of nanolayered TiAlN/TiSiN coating deposited on WC-Co cemented carbide

In this study, high-temperature tribological behavior of nanolayered TiAlN/TiSiN coating was evaluated against the Al2O3 counter-body using a pin-on-disk tribometer. The coating was deposited on the WC-Co substrate, in an industrial unbalanced magnetron sputtering system. Tribological tests were conducted at room temperature, 500, 600, 700, and 760 °C, in air and nitrogen atmospheres. After the tests, the coating was examined using confocal microscopy, tactile profilometry, scanning electron microscopy, focused ion beam, energy dispersive spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and secondary ion mass spectrometry. The coating retained its microstructure and mechanical properties after exposure to high temperatures. At lower temperatures coating exhibited abrasive and adhesive wear mechanisms, while at higher temperatures abrasive and oxidative wear mechanisms were observed. In high-temperature tests, AlO, TiO and SiO were detected inside of wear tracks, in both atmospheres. However, the oxide thickness was significantly lower in tests with nitrogen atmosphere. Additionally, the top of the oxide layer was enriched in AlO with respect to TiO and SiO. The enrichment of AlO was more pronounced in nitrogen atmosphere. The coating tested in air exhibited slightly higher and more unstable coefficient of friction (COF) values, than in nitrogen atmosphere. This is attributed to the increased oxidation in air atmosphere. At room temperature tests in nitrogen, the wear rate was approximately 3 times lower than in air. At higher temperatures the wear rate was lower than at room temperature, in both atmospheres, due to formation of protective oxides. However, with the increase in testing temperature the wear rate increased. The reason for such behavior is the loss of substrate's and coating's hardness at high temperatures, and thickening of the oxide layer which accelerated its removal. The latter effect is not so pronounced in nitrogen atmosphere due to thinner oxide layer, which agrees with the lower wear rate in nitrogen atmosphere at high temperatures than in air.

Effect of Nb and V doped elements on the mechanical and tribological properties of CrYN coatings

One of the most promising approaches to enhancing the tribological properties of engineering coatings is to add transition elements to the structure. In this study, Nb-doped CrYN and V-doped CrYN thin films were deposited by pulsed DC reactive sputtering in a closed-field unbalanced magnetron sputtering (CFUBMS) system. The deposition parameters examined were target current (1, 1.5 and 2 A), deposition pressure (0.15, 0.25 and 0.35 Pa), pulse frequency (100, 200 and 350 kHz) and duty cycle (85 %, 70 % and 50 %). A Taguchi L9 orthogonal design was used to define the deposition process parameters for each doped film. The Nb and V-doped CrYN thin films were characterized in terms of their microstructure, thickness, composition, hardness and tribological properties by X-ray diffraction (XRD), scanning electron microscopy (SEM), Energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), nanohardness and pin-on-disc testing, respectively. The bond strength between the substrate and the films (adhesion) was analyzed by scratch testing. For the Nb-doped thin films, a maximum hardness value of 21.4 GPa and the lowest friction coefficient of 0.36 were obtained. On the other hand, in the V-doped thin films, the maximum hardness value was 16.1 GPa, while the lowest friction coefficient obtained was 0.11. In addition, Nb-doped and V-doped CrYN thin films exhibited extraordinary adhesion properties. The effect of the selected deposition parameters (target current, pulse frequency, and duty cycle) in relation to the film thickness, hardness, and coefficient of friction properties of the Nb and V-doped CrYN thin films were investigated using the Taguchi approach and optimum operating conditions were identified and confirmed.

Mechanical, Tribological, and Corrosive Properties of NbCrCx and NbCrCxNy Coatings with Various Nitrogen and Carbon Contents

CrC and NbC carbide coatings both have good mechanical properties, wear resistance, and corrosion resistance. The present study seeks to combine the two coating systems in order to further enhance their properties. NbCrCx and NbCrCxNy coatings (where x and y denote the atomic percentages of carbon and nitrogen, respectively) were deposited on SKH51 substrates using a radio-frequency unbalanced magnetron sputtering system. The mechanical, tribological, and corrosive properties of the coatings were investigated and compared. Among the NbCrCx coatings, the NbCrC61 coating showed high levels of hardness, excellent adhesion strength, and good wear resistance. Among the NbCrCxNy coatings, the NbCrC55N5 coating showed high adhesion strength and hardness and excellent tribological properties. However, for nitrogen contents greater than 16 at%, the adhesion strength was dramatically reduced, resulting in poor tribological performance. Among all of the coatings, the NbCrC49 coating showed the best corrosion resistance due to its enhanced crystallinity, high adhesion strength, moderate surface roughness, and high sp3 C-C bonding ratio.

Clean fabrication strategy of diamond crystals containing nanocomposite films for corrosion and wear protection of AISI-321 alloy

This study focused on the synthesis of Niobium/Hexagonal-Diamond/Amorphous-Carbon (Nb/H-D: a-C) films on AISI-321 alloy. The substrate heating used as a vital deposition parameter to tailor structure of the films in an unbalanced magnetron (UB-M) sputtering system for the first time. The substrate heater temperature (Th) ranged between (RT) to 150 °C. The results indicated that increasing the substrate heater temperature promoted the abundance of hexagonal diamond (H-Diamond) crystals through the solid phase separation. Therefore, the film deposited at the highest temperature (150 °C) demonstrated the highest plenty of H-Diamond. Electrochemical impedance spectroscopy (EIS) measurements (after 2, 8, 24, 72, and 168 h immersion) and polarization tests (after 168 h immersion) disclosed that increasing the substrate heater temperature positively affects the corrosion resistance of (Nb/H-D: a-C) films. The results proved that the film deposited at the highest temperature of 150 °C, demonstrated the exceptional corrosion protection efficiency of 99.69 %. Moreover, this film presented acceptable low-frequency impedance (|Z|10KHz) and total resistance (Rt) values of >108 Ω·cm2 and >117 MΩ·cm2 at all immersion times in 3.5 wt% NaCl solution. The highest abundance of the H-Diamond phase, with remarkable chemical inertness at higher substrate heater temperatures, can be an effective reason for elevating anti-corrosion performance of the films. Additionally, as the substrate heater temperature enhanced from RT to 150 °C, mechanical properties illustrated an remarkable increment trend (increasing hardness from 20 to 32.7 GPa and the elasticity modulus from 407 to 470 GPa). Moreover, the anti-wear performances of the films significantly improved with increasing substrate heater temperature, reducing the wear rate from 9.4 × 10−6 to 9 × 10−7 mm3/N·m. These results are mainly attributed to the highest abundance of the superhard H-Diamond phase in the film deposited at higher substrate heater temperature. In conclusion, the (Nb/H-D: a-C) film synthesized at 150 °C represented a promising candidate for tailoring the electrochemical and anti-wear performances of AISI-321 alloy.

Tribological behavior of a novel Si- and WC- co-reinforced a-C multilayer coating at 25– 500 °C

To improve the applicability of a-C coatings in a wide temperature range, a novel Si- and WC- co-reinforced amorphous carbon coating (SiC-nWCC), consisting of Si-doped a-C nanolayers and WC/a-C nano-multilayers, is proposed in this paper. A series of SiC-nWCC coatings with different modulation ratios (0.49–1.98) were fabricated by a closed field unbalanced magnetron sputtering system. The influences of modulation ratio on the microstructure, mechanical properties together with thermal stability of SiC-nWCC coatings were explored. The tribological behaviors of SiC-nWCC coatings against M50 steel balls were investigated at room temperature to 500 °C in ambient air. The results show that the SiC-nWCC coating with the modulation ratio of 1.98 achieved superior wide-temperature applicability, featuring the average friction coefficient lower than 0.17 and the wear rate less than 9.84 × 10−6 mm3/N·m in the whole temperature range of 25–500 °C. The excellent wide-temperature tribological performance of the SiC-nWCC coating are mainly attributed to the good thermal stability and the formation of temperature adaptive tribological layers. At 25 °C, sp2-rich carbon is the main lubrication phase of tribological layers, and at 200– 400 °C, the lubrication performance of coating relies on both sp2-rich carbon and Si-rich oxides, and at 500 °C, the self-lubrication phases of Si-rich oxides and WO3 are account for the outstanding lubricating performance of coating. This work provides a profound insight for developing the wide-temperature applicable a-C based coatings.

Study on the effect of counter ball materials on fretting wear behavior of solid lubricating films

Solid self-lubricating film can undoubtedly play a superior role in improving the micromotion behavior. The friction pairs of different materials have different fretting behavior and wear mechanism due to their different mechanical properties and surface adhesion properties. Investigating the influence of mechanical properties and surface adhesion on the fretting behavior can make the self-lubricating solid film play a better effect in the practical fretting working conditions. Here, DLC film and MoS2 film are deposited on AISI 304 stainless steel using a TeerUDP-650 unbalanced magnetron sputtering system. The fretting performance of DLC and MoS2 films resistance to GCr15, Al2O3, SiC and Si3N4 balls are studied. The results demonstrate that the fretting characteristics of DLC film are highly dependent on the mechanical properties and adhesion behavior of counter balls. Thereinto, Al2O3 balls show excellent fretting behavior, while SiC and Si3N4 balls make DLC film ineffective due to their high hardness and high adhesion. The MoS2 film maintains low friction and low wear state against any counter ball. DLC film achieves anti-fretting wear via graphitization, while MoS2 film primarily relies on slip and plastic flow. This work provides a theoretical reference for proper selection of solid lubricating films and counter balls under practical fretting conditions and reveals the different tribological mechanisms of friction pairs.

High-Temperature Oxidation Behaviour of CrSi Coatings on 316 Austenitic Stainless Steel.

In this study, a closed-field unbalanced magnetron sputtering system, which is environmentally friendly and has high deposition efficiency, was used to deposit CrSi coatings on 316 austenitic stainless steel. This system utilised separate Cr and Si targets, and the appropriate content of Cr and Si of the coatings was adjusted by changing the currents applied to the targets. A series of CrSi coatings with different Si/Cr ratios were produced, and their oxidation behaviour at elevated temperatures was investigated. By analysing the weight gain, surface morphology and microstructure, composition and phase constituents, the oxidation behaviour at 600 °C, 700 °C and 800 °C was investigated and the optimized coating to protect the stainless steel has been identified. The outcome of the research indicated that a small amount of Si (between 4-7 at.%) in Cr coatings is effective in protecting the austenitic stainless steel against oxidation at high temperatures, while a high Si content (around 10 at.% or more) makes the coating more brittle and prone to cracking or delamination during oxidation at 800 °C.

Silicon wafer as a feasible candidate for tribological characterization of thin coatings under high contact stress?

Silicon (Si) wafer is generally used as the substrate for structural analysis and residual stress measurement of thin coatings. A few studies can be found for mechanical and tribological characterization wherein Hertzian contact stress never exceeded 1 GPa. Si, being single crystal, pure, and having low surface roughness (Ra) is an ideal potential candidate for thin coating analysis. However, Si wafer breaks immediately under higher contact stress. The current study aims to push the contact stress limit to test thin coatings on Si wafer especially for friction and wear testing. To serve the purpose, different bias DLC coatings (−120 V, −80 V, −40 V, Zero V, +40 V, +80 V, +120 V) were deposited on Si wafer employing closed field unbalanced magnetron sputtering (CFUMS) system. Using conveniently available experimental approach, Hertzian contact stress in tribological tests has been pushed up to 2.6 GPa successfully on DLC coated Si wafer. Thus, it is feasible to test thin coatings on Si wafer at high contact stress which will provide useful and consistent friction and wear data such that further test using the steel substrate will be reduced by a significant margin. A thorough mechanical, tribological and structural (Raman) analysis is presented. It was found that −120 V possessed the highest hardness (H: 17.6 GPa), modulus (E: 184 GPa) and residual stress (4.5 GPa). The same coating produced the lowest sp2/sp3 ratio, wear rate using contact stress (0.092 × 10−13 mm4/N) and wear/friction energy (0.071 × 10−13 mm3/J2) in comparison to other coatings used in the study. Counter body analysis for −120 V shows the minimum scratch area depicting friction between transfer film and DLC hence the lowest coefficient of friction (0.061) was obtained. Moreover, surface topography is explained with the aid of atomic force microscope (AFM) images and surface roughness (Ra) data. AFM revealed craters and bumpy like surfaces for positive and negative biased samples respectively.

Comprehensive effect of grain size and original target morphology on sputtering behavior of magnetron sputtering target

In this paper, the etching morphology, surface roughness, target voltage, and light emission line intensity of the copper target were investigated using a closed-field unbalanced magnetron sputtering system equipped with optical emission spectroscopy monitor (OEM). The results show that the morphology of the sputtering zone, the target voltage value, the surface roughness, and the OEM value are significantly correlated with the grain size of the target. After sputtering, the original target's morphology dramatically influences the surface roughness and OEM value.

Mechanical properties, electrochemical performance and interfacial contact resistance of as-deposited and annealed NbxAlyC and CrxAlyC coatings on stainless steel 316L substrates

NbxAlyC and CrxAlyC coatings (where x is the Nb or Cr target current and y is the Al target current) were deposited on stainless steel 316L substrates using a radio frequency unbalanced magnetron sputtering system. The sputtered NbxAlyC and CrxAlyC coatings were vacuum annealed at 800°C and 750°C for 1 h, respectively. The cross-sectional and surface morphologies of the as-deposited coatings showed a columnar structure and a loose surface, respectively. The X-ray diffraction results showed that the annealed NbxAlyC and CrxAlyC coatings contained Nb2AlC and Cr2AlC MAX crystalline phases, respectively, The MAX crystalline phase improved the hardness, corrosion resistance, and electrical conductivity of the coatings. The annealed coatings also formed an Al2O3 layer with a small cluster size and a dense surface, which significantly improved the corrosion resistance compared to that of the as-deposited coatings. The electrochemical test results showed that the corrosion current density (Icorr) and interfacial contact resistance (ICR) values of all the annealed coatings were lower than those of the as-deposited coatings and were consistent with the standard for the bipolar plates in commercial proton exchange membrane fuel cells. Among all the coatings, the annealed Nb2.5Al0.5C-H coating showed the lowest Icorr and ICR values.

Effect of silicon-doping on the wide-temperature tribological behavior and lubrication mechanism of WC/a-C film

To expand the lubricating temperature range of a-C based film in air atmosphere, a novel Si and WC co-doping Si/WC/a-C film was proposed. The Si/WC/a-C film with different Si contents were prepared by an unbalanced magnetron sputtering system. The effects of Si on the microstructure, thermal stability and mechanical properties of WC/a-C films were explored, and its wide-temperature tribological behaviors against M50 steel were researched at temperatures ranging from 25 °C to 500 °C in air atmosphere. The Si-doping inhibited the crystallization of WC in films, leading to the microstructural transformation from nanocrystalline-amorphous to amorphous. The introduction of Si significantly improved the nanohardness, thermal stability and wide-temperature lubrication properties of WC/a-C film. Therein, the Si/WC/a-C film with 18.85 at.% Si exhibited the best tribological performance featuring the average friction coefficients less than 0.25 at 25–500 °C. Its prominent wide-temperature lubrication performance can be attributed to the successive generation and their combined effect of the self-lubricating phases of sp2-rich carbon, Si–O–C and WO3 in different temperature ranges. Remarkably, appropriate Si-doping can effectively inhibit the oxidation of sp2-rich carbon in tribological layers, thus it is the dominant lubrication phase throughout the wide temperature range of 25–500 °C.

Tribological properties of Mn–TiN films and formation of graphite-like layers in physiological solution

TiN film and Mn–TiN films containing 2.2, 5.6, and 10.6 at% Mn were deposited on appropriate substrates using a four-target unbalanced magnetron sputtering system. The Mn contents of films were adjusted by controlling the number of Ti–Mn alloy rods embedded in the titanium target. The effects of Mn doping on the microstructure, mechanical properties, and wear properties of TiN films were systematically investigated. A relatively loose columnar structure is observed in the TiN film, which is refined and densified by the incorporation of Mn. Mn doping improves the hardness, toughness, and adhesion performance of TiN films. The Mn–TiN films containing 2.2 and 5.6 at% Mn, in particular, exhibit superior mechanical properties. Moreover, the presence of Mn has a promoting effect on the wear of TiN films in both phosphate buffer (PB) and bovine serum albumin (BSA) solutions. The Mn ions released from Mn–TiN films during friction in a BSA solution promote the formation of protein deposits. The structures of protein molecules in these deposits denature under the frictional shear force of SiC balls during sliding tests, forming graphite-like layers on the friction interfaces. These layers act as a solid lubricant and improve the wear resistance of films.

Microstructure, mechanical properties and low-temperature tribological behavior of Cr/Cr-W/W-DLC/DLC multilayer coatings on 5A06 Al alloy

In this study, the Cr/Cr-W/W-DLC/DLC multilayer coating was deposited on 5A06 Al alloy using a combination of unbalanced magnetron sputtering system and filter cathode vacuum arc technique. Dry linear reciprocating sliding wear tests were performed to evaluate the tribological properties of the deposited coating at different temperatures from −100 °C to 25 °C. The microstructure, mechanical properties and wear characteristics of the multilayer coating were also characterized by SEM, EDS, nanoindenter and nanoscratch tester, respectively. The results show that, compared with 0 °C and 25 °C, the tribological behavior of the multilayer DLC coating exhibits significant differences at low temperatures. The formation of the transfer layer and the graphitization caused by the flash temperature contribute to explain the excellent tribological performance of the coating at room temperature and 0 °C. The deterioration of the tribological properties of the multilayer coating at subzero temperatures is ascribed to the inhibition of the graphitization process, as well as the oxidation and capillary action of water molecules. Cyclic shear stress and low temperature lead to the formation of microcracks and surface spalling, which also increases the friction coefficient and wear rate of the multilayer DLC coating.

The effects of Cr and B doping on the mechanical properties and tribological behavior of multi-layered hydrogenated diamond-like carbon films

To enhance the adhesion strength and tribological properties of hydrogenated diamond-like carbon (H-DLC) films, the multi-layered H-DLC films consisting of a function layer with chromium and boron doping, Cr-C and Cr-H-DLC transition layer and a Cr bonding layer were prepared on 52100 steel through the unbalanced magnetron sputtering system. The influence of Cr and B doping on the mechanical properties and tribological performance were investigated. The results indicated that the structure of H-DLC, Cr-H-DLC and B-H-DLC films was compact. There were no peelingflake, delamination, and crack between the films and substrate. Raman spectra showed that the value of ID/IG increased with the Cr and B doping, which indicated that the sp3 content inside the H-DLC film decreased. Compared with the atmospheric condition, the coefficient of friction and wear rate of those films were higher than that in vacuum. According to the Raman spectra of the wear track, it was found that the graphitization of sliding interface theory had its limitations. The mechanical wear of those films was dominated by the abrasive and oxidative wear in the atmospheric environment. Owing to the passivation of the hydrogen atoms, the abrasive wear and adhesive wear was the main failure mechanism in vacuum.

The enhancement of individual friction and corrosion properties of CrSiN coatings by Mo doping in seawater

A series of CrSiN coating with various Mo contents were fabricated on Ti6Al4V alloys using a closed unbalanced magnetron sputtering system and their tribological and electrochemical behaviors were investigated. The results of friction tests suggested that oxidation behaviors of Mo element in the prepared coatings promoted the wear mechanism transforming to tribochemical wear, and the more Mo doping enhanced the tribological performance and presented the lowest wear rates of 2.27 × 10 −7 mm 3 /N.m and 8.12 × 10 −8 mm 3 /N.m for tribopairs of Cr( Mo )SiN/Al 2 O 3 and Cr( Mo )SiN/Si 3 N 4 , respectively. Besides, the corrosion product of MoO 3 reduced the corrosion rate of CrMoSiN coatings, CrMoSiN coating showed the low corrosion rate of 0.58 × 10 −3 mm/yr indicated that the passive behaviors of Mo element improved the corrosion resistance, and provided a good protection to Ti6Al4V alloys in seawater. • Cr( Mo )SiN coatings were successfully fabricated using the unbalance magnetron sputtering system. • The oxidization behaviors of Mo element decreased the friction coefficient. • The wear mechanism would be transformed to tribochemical wear with an increase in the Mo content. • The more Mo element doping enhanced tribological performance of CrMoSiN coating in seawater. • The corrosion rate and current density were slowed down due to the passive behaviors of Mo element on coating's surface.

Characteristics of Palladium Doped Amorphous Carbon Films Fabricated by Unbalanced Magnetron Sputtering System

Generally, hydrogenated amorphous carbon (a-C:H) has been shown to have a low friction coefficient, high hardness, and low abrasive wear rate. In this study, Pd doped hydrogenated amorphous carbon (a-C:H:Pd) fabricated by the closed-field unbalanced magnetron sputtering (CFUBMS) system with two targets of carbon and palladium in Ar/C2H2 plasma. The tribological and lubricant characteristics for a-C:H:Pd fabricated with various DC bias voltage from 0 to −200 V were investigated. We obtained a hardness up to 27.5 GPa and friction coefficient lower than 0.1. The atomic percentage of Pd related to the lubricant properties increased up to 22% at −200 V. In the results, the Pd doping in the a-C:H films improved the tribological and lubricant properties. The friction coefficient value of a-C:H:Pd films was decreased, the hardness and elastic modulus were increased, and also the adhesion properties was improved with the increase of negative DC bias voltage.

Effect of microstructure and mechanical properties on the tribological and electrochemical performances of Si/DLC films under HCl corrosive environment

Si-doped diamond-like carbon (Si/DLC) films appear very attractive due to their superior mechanical and tribological properties and chemical inertness. In the present work, Si/DLC films with silicon concentration from 1.64 to 15.32 at.% were fabricated on 304 stainless steel by adjusting Si target current using unbalanced magnetron sputtering system. The microstructure, surface morphology and mechanical properties of the films with different Si concentration, as well as the tribological and electrochemical properties of the films under HCl corrosive environment were systematically investigated. Results showed that Si doping increased the sp3 CC content, hardness, and elastic modulus of as-fabricated films, lowered the residual stress, but deteriorated the adhesion strength. At the same time, the appropriate Si concentration was conducive to low surface roughness and dense microstructure. The Si/DLC films presented good tribological performances in 1 M HCl solution, including low friction coefficient and wear rate. The degradation of tribological properties was attributed to the synergistic effect of less solid lubrication, declined adhesion strength, worse resistance to elastic and plastic deformation. The wear mechanism was mainly dominated by abrasive wear. Furthermore, the Si/DLC film with 15.32 at.% Si provided the best corrosion resistance, which benefited from its dense structure, higher thickness, and the highest sp3 CC content.