HK1060375A - Diamond-like carbon (dlc) coating system with improved antifriction properties and method for producing a coating system of this kind - Google Patents

Description

The present invention relates to a shift system of patent claim 1, a process of patent claim 21, and a device of patent claim 40. Preferred embodiments of the invention are disclosed in subclaims 2 to 20, 22 to 39 and 41 and in the description, examples and drawings.

Despite the outstanding properties of diamond-like carbon layers (DLC layers), such as high hardness and excellent slip properties, and many years of research worldwide, to date no pure DLC layers have been produced which, even at larger layer thicknesses (> 1 μm), exhibit sufficient layer adhesion for industrial use in typical wear protection applications and sufficient conductivity to avoid the high frequency (HF) manufacturing processes which have many production disadvantages.

Typical wear protection applications are, on the one hand, applications in the mechanical engineering sector, such as protection against slip, pitting, cold welding, etc., in particular on parts with interlocking surfaces, such as gears, pump and cup sockets, piston rings, injector needles, complete bearings or their individual components, etc., and, on the other hand, applications in the material handling sector for the protection of the tools used for spinning or forming and in injection moulds.

In addition to the versatile application possibilities in the area of wear protection, corrosion protection is also mentioned as another promising area of application of such DLC layers.

Pure DLC layers can now be deposited with only low layer thicknesses, insufficient for many applications, or have to be altered in their properties by the addition of foreign atoms, such as silicon, various metals and fluorine, due to the high intrinsic stresses and the associated problematic adhesion, especially in high-stress surfaces in wear protection.

The addition of additional coatings containing, for example, graphite carbon and/or a mixture of metal or metal carbide and carbon could not therefore be considered, since, on the one hand, the minimum coating thickness necessary to achieve the coating effect created additional harmful coating stresses and, on the other hand, the adhesion to pure carbon layers was problematic.

Due to the high electrical resistance of hard DLC layers, processes with an HF bias or plasma (hereinafter HF = high frequency, meaning all frequencies > 10 MHz) are often used in the current plasma-based processes for the production of DLC layers, especially with the industrial frequency of 13.56 MHz. The known disadvantages of this technique are difficult to control disturbances of electronically sensitive sub-process control units (HF feedback, transmitter overheating, a precise increase in the effort to avoid interfering charges during coating, to avoid interfering with the HF substrate, and thus to prevent the exposure of the plasma substrates and thus an optimal minimum of damage between the layers, such as high-energy discharge and the formation of a relatively undesirable thermal discharge in the substrate, and, on the other hand, the formation of a negative charge in the plasma substrate, which is often caused by a negative charge of the plasma substrate and a false charge of the plasma substrate.

Because of the exponential dependence of the substrate stress on the substrate surface calculated in RF processes $\text{US/UE=CE/CS=(AE/AS)4}$ The coating is not possible to achieve the ionic effect required for the well-adhesive layer thickness, otherwise either not enough power can be introduced into the system or the potential difference (substrate voltage) cannot be set high enough to achieve the ionic effect required for the well-adhesive layer thickness.

Furthermore, on the plant side, in RF processes, additional apparatus is usually required to dynamically adjust generator and plasma impedances through electrical networks, such as a so-called matchbox, during the process.

The following is a brief list of various techniques or shift systems known from the state of the art.

EP 87 836 reveals a DLC layer system with a metal component content of 0.1 to 49.1% which is deposited, for example, by cathodic sputtering.

DE 43 43.354 A1 describes a method for producing a multilayered tilated layer system with a solid layer of titanium nitride titanium carbide and titanium boride and a friction-reducing C-containing surface layer, whereby the Ti and N-proportion is progressively reduced towards the surface.

The method described in US 5 078 848 for the production of DLC layers uses a pulsed plasma beam, but due to the directed particle radiation from a source with a small exit cross section, such methods are only partially suitable for uniform coating of larger areas.

The following documents describe various CVD processes or SiDLC/DLC mixtures produced by such processes:

EP-A-651 069 describes a friction-reducing wear protection system of 2-5000 alternating DLC and SiDLC layers. A method for separating a-DLC layers with a Si-intermediate layer and a subsequent a-SiC:H transition zone to improve adhesion is described in EP-A-600 533.

US 4 728 529 describes a method of separating DLC using an RF plasma, where the layering is carried out at a pressure range of 103 to 1 mbar from an oxygen-free hydrocarbon plasma to which noble gas or hydrogen is added if necessary.

The process described in DE-C-195 13 614 uses a bipolar substrate voltage with a shorter positive pulse duration in a pressure range of 50-1000 Pa. This produces coatings in the range of 10 nm to 10 μm and a hardness of 15-40 GPa.

A CVD process with a substrate voltage generated independently of the coating plasma is described in DE-A-198 26 259, preferably using bipolar but also other periodically modified substrate voltages, but this requires a relatively complex electrical supply unit to perform the process, as it is to be provided in a double design.

In addition, methods combining traditional hard coatings with a carbon-rich coating with favorable slip properties have been known for some time. For example, US 5.707.748 reveals a layer combination of metal-containing hard material layers (TiN, TiAIVN, WC) and a less hard metal carbide layer with increasingly graphitic, i.e. sp2 hybridized, bound carbon. Due to the good conductivity of metal/ or metal carbide/carbon layers (MeC/C), these are preferred for use in tribosystems where, in addition to protecting the coated part, a reduction in frictional forces and/or protection of the metal body is to be achieved. Special performance has been achieved with respect to carbon/C layers with a high percentage of C59 by means of a layer containing 99 C29 or C59 carbon, which can be achieved by a combination of a soft material covering the entire layer, and a similar effect for a metallic layer with C59 or C29 carbide.

Accordingly, the present invention is intended to provide relatively thick DLC layer systems with high hardness and excellent adhesion strength, which are also conductive enough to be separated without RF bias, so that a process and device can be used that does not require much effort and has a high efficiency for industrial use.

This is done by the layer with the characteristics of feature 1 and the procedure of feature 11 and the device of feature 30.

Surprisingly, it has also been shown that it is possible to apply a particularly favourable slip and, if desired, slip-in properties to relatively thick DLC layers with an additional layer without deteriorating the adhesion strength, thus for the first time combining the high hardness of pure DLC layers with the favourable slip properties of metallic carbon layers. This can be done not only by applying slip layers to inventive DLC layer systems, but also by applying one of the methods described for applying a slip layer to known DLC layers or DLC layer systems.

The present invention is therefore intended in particular to provide a DLC or a diamond layer with excellent adhesion strength and high wear resistance, which has improved slip properties and, if desired, slip properties compared to conventional DLC or diamond layers.

A further function of the invention is to provide a method and device for the manufacture of a DLC smooth coating system according to the invention.

This is solved according to the invention in accordance with paragraph 1 of the specification.

The shift system

A DLC layer system of the invention is achieved by producing a layer with the following layer structure.

Directly on the substrate is an adhesive layer containing at least one element from the group of elements of subgroups IV, V and VI and Si. Preferably, an adhesive layer from the elements Cr or Ti which has proved particularly suitable for this purpose is used.

This is followed by a transition layer, preferably a gradient layer, during which the metal content and the C content increase perpendicular to the substrate surface.

The transition layer consists mainly of carbon and at least one element from the group of elements that make up the adhesive layer. In addition, hydrogen may be present in a preferred embodiment. In addition, both the transition layer and the adhesive layer contain unavoidable impurities, such as those produced by atoms embedded in the layer from the surrounding atmosphere, such as the noble gases used in the manufacture, such as argon or xenon.

In the case of the formation of the transition layer in the form of a gradient layer, the increase of carbon towards the deck layer may be achieved by increasing, where appropriate, different carbide phases, by increasing free carbon, or by mixing such phases with the metal phase of the transition layer. The thickness of the gradient or transition layer may be adjusted by adjusting, as the professional knows, the appropriate process ramps. The increase in C-content or decrease in the metal phase may be continuous or gradual, and at least in part of the transition layer a reduction of metal-rich and C-rich layers may also occur as a result of further continuous deposition of layers.

The final layer of the layer package is essentially a layer consisting exclusively of carbon and preferably hydrogen, with a thicker layer compared to the adhesive and transition layer.

The hardness of the entire DLC layer system is set to a value greater than 15 GPa, preferably greater/equal to 20 GPa, and an adhesive strength better or equal to HF 3, preferably better or equal to HF 2, in particular equal to HF 1 according to VDI 3824 sheet 4 is achieved. The hardness is measured using the Knoop hardness measurement with o,1 N load, i.e. HK0.1.

The layer thicknesses are > 1 μm in total, preferably > 2 μm, with the adhesive layer and the transition layer preferably having layer thicknesses of between 0,05 μm and 1,5 μm, in particular between 0,1 μm and 0,8 μm, while the cover layer preferably has a thickness of between 0,5 μm and 20 μm, in particular between 1 μm and 10 μm.

The H content in the deck layer is preferably 5 to 30 atomic %, in particular 10 to 20 atomic %.

In REM images, separate DLC layer systems according to the invention show a fracture surface which, unlike conventional DLC layers, have a fine grained structure, not a glassy amorphous one, with a grain size preferably ≤ 300 nm, and in particular ≤ 100 nm.

In tribological tests under high stress, the coating has a multiple lifetime compared to other DLC layers, such as metallic carbon, especially WC/C layers, for example, a DLC-coated injection nozzle for combustion engines was found to wear only slightly after 1000h, whereas in the same test a WC/C coated nozzle was found to wear only after 10h on a high surface wear to the base material.

The layer stiffness of the DLC layer according to the invention is preferably Ra=0.01-0.04; where Rz is preferably < 0.5 as measured by DIN < 0.8.

The advantages of a DLC layer system of the above characteristics, as described in the present invention, are the first successful combination of large layer thicknesses with excellent adhesion strength, which still have sufficient conductivity to allow relatively easy process management in industrial production.

Despite the high hardness of > 15 GPa, preferably ≥ 20 GPa, the layer shows a significantly improved adhesion due to its structure and the steps of the invention.

REM fracture images of the layer of the invention also show, in contrast to previously known DLC layers, which have the typical fracture shape of an amorphous brittle layer with partially shell-like bursts, a fine-grained, straight fracture surface. Layers with the property profile described above are particularly suitable for applications in mechanical engineering, such as coating high-load pump or cup nozzles and valve drives, cams or camshafts, as used for automotive combustion engines and transmissions, but also for protecting high-load toothed tops, pulleys, pump spindles, etc. in particularly hard and slippery areas where a particularly hard surface with good sliding properties is required.

In the tooling sector, these layers can be used advantageously, due to their high hardness and very smooth surface, especially for forming (pressing, stamping, deep drawing, ...) and injection moulding tools, but also, with certain restrictions in the processing of iron materials, for cutting tools, especially when the application requires a low coefficient of friction coupled with a high hardness.

The growth rate of the DLC layer is about 1-3 μm/h, the layer voltage for the whole system is 1-4 GPa and thus in the usual range of hard DLC layers.

The slipperiness obtained by the DLC layer systems according to the invention is more favourable than that obtained by other layers, e.g. nitrides and/or carbides, but neither the extremely low coefficients of friction which can be achieved by metal/carbon layers nor is it suitable as an inlet layer.

If the slip or slip properties of the DLC layer or DLC layer system are to be further improved, a final softer slip layer containing a relatively high proportion of graphite carbon is recommended.

The latter can also be applied advantageously to non-inventive DLC layers and layer systems and to diamond layers, in particular nanocrystalline diamond layers.

The following describes the construction of a DLC sliding layer system according to the invention, which, advantageously but not in any way restrictive, consists of a DLC layer system with a sliding layer deposited on it as described above.

One particularly advantageous embodiment of the friction-reducing layer, particularly suitable for application to the inventive DLC layer system described above, is a DLC structure without metallic additive but with an increasing proportion of sp2 bonds, preferably in a graphic layer structure, which reduces the hardness of the deck layer and improves the slip and, where appropriate, the slip properties.

Another advantageous design of the slide can be achieved by forming a second, inverse gradient layer, in which the metal content increases to the surface, but the C content decreases. The metal content is increased until the coefficient of friction reaches a desired low value. Preferably one or more metals from subgroups IV, V, VI, and Si are used.

A further preferred version of the friction-reducing layer can be obtained by applying a metallic or carbide layer, in particular a Cr or WC intermediate layer, to the layer consisting essentially exclusively of carbon and hydrogen, followed by a gradient covering layer similar to the first gradient layer, with decreasing metal and increasing C content.

Surprisingly, it has been shown that metal-containing sheets can also provide a significant improvement in performance on traditionally separated DLC sheets, and one reason for the low impact on the overall performance of such systems may be due to the low additional layer voltages that are easily adjustable.

For all three options, it has proved advantageous to provide a closing area with an unchanged i.e. constant layer composition in order to maintain the properties of the layer optimized for the application (e.g. friction, surface tension and wettability, etc.) even over a certain layer wear and to allow the layer to recede.

The friction value can be set between μ = 0.01 and μ = 0.2 depending on the metal used and the remaining excess of gaphitic carbon (relating to a pen/disk test under normal atmosphere with approximately 50% humidity).

The DLC hardness is preferably set to a value greater than 15 GPa, preferably greater than or equal to 20 GPa, and the hardness of the overlying softer glue layer is adjusted as required.

The integral hydrogen content of the layer system of the invention is preferably set to a content between 5-30% atomic, in particular between 10-20% atomic.

The layer stiffness can be set to a Ra value of less than 0,04 preferably less than 0,01 or to an RzDIN value of less than 0,8 preferably less than 0,5.

The advantages of such DLC smooth coating systems according to the invention lie in the combination of the high hardness of the DLC layer, coupled with a smoothness characteristics improved by up to an order of magnitude compared to the already good running performance of the DLC layer. For example, the coefficient of friction can be reduced to below μ = 0.1. Furthermore, for the first time, DLC layers can also be given a contraction by initial layer loss and graphite antibody lubrication, which can also significantly reduce the wear of an uncoated antibody.

Furthermore, using a pure DLC layer described above can set a lower Rz or Ra number, i.e. lower roughness of the coated surfaces, than with traditionally used resin layers, especially applied with the arc process. In such known resin/slip layer combinations, particularly hard roughness peaks can often disrupt or even prevent the entry of the tribosystem, which can lead to partial or complete destruction of the surface of a triblayer, especially if it is not itself protected by a hard layer of glaze.

The superiority of DLC-slip-layer systems was shown here in various applications both over known solid/slip-layer combinations and over pure DLC-layer systems.

In the tool sector, too, these layers can be used advantageously, due to their high hardness and very smooth surface, especially for forming (pressing, stamping, deep drawing, ...) and injection moulding, but also with certain restrictions in the processing of iron materials for cutting tools, especially if a particularly low coefficient of friction is desired for the application, possibly coupled with a defined flow effect.

The DLC smooth coating systems of the invention can be smoother than conventional, e.g. with arc evaporators, to deposit solid/smooth coating combinations (e.g. TiA1N/ /WC/C) and more easily integrated into a continuous process than, for example, the also known Ti-DLC // MoSx coating combinations.

The Commission shall:

The method of manufacture of the DLC layer system according to the invention has further characteristics.

The parts to be coated are cleaned in a way known to PVD processes and mounted on a support device. Unlike RF processes, it is advantageous to use support devices with 1, 2 or even 3 axes of rotation essentially parallel, depending on the particle geometry, which can achieve a greater load density. The support device with the parts to be coated is taken to the process chamber of a coating plant and after pumping at a starting pressure of less than 10-4 mbar, preferably 10-5 mbar, the process is started.

The first part of the process, the cleaning of the substrate surfaces, is carried out, for example, as a heating process to remove the volatile substances still adhering to the surface of the parts. For this purpose, preferably a noble gas plasma is ignited by means of a high current/low current charge between one or more filaments placed on a negative potential in an ionization chamber adjacent to the process chamber and the holding devices with the parts placed on a positive potential. This results in an intense electron shedding and a variable heating of the parts. The use of a low-energy/H2O-compound has been shown to be particularly advantageous, whereby the high current of the hydrogen used at the same time can be used to achieve a low-energy effect or a significantly lower electron charge in the ionization field above the surface of the chamber or a stationary electron charge can be used to reduce the ionization effect.

Alternatively, other heating methods such as radiant heating or inductive heating can be used.

After reaching a temperature level to be determined depending on the base material of the parts, an aeration process can be started as a cleaning process, for example by igniting a low-voltage arc between the ionization chamber and an auxiliary anode, and the ions are pulled onto the parts by means of a negative bias voltage of 50-300 V. The ions bombard the surface and remove residual impurities.

The process can also be carried out by applying a pulsed substratum bias voltage without or with the support of a low-voltage arc, as described above, preferably using a medium frequency bias in the range from 1 to 10 000 kHz, in particular between 20 and 250 kHz.

To ensure the adhesion of the DLC layer system to the substrate, a preferably metallic, in particular Cr or Ti, adhesive layer is evaporated by a known PVD or plasma-CVD process, such as arc evaporation, various ion plating methods, but preferably by cathodic sputtering of at least one target. To support the evaporation, a negative substrate bias voltage is applied to the substrate. Ion protection and the resulting layer compaction during the sputtering process may be further supported by a parallel low voltage arc and/or a stabilization or intensification of the plasma magnetic field, and/or by the application of DC bias voltage or by the application of a medium bias chamber on the substrate between 1 and 10 000 kHz, in particular in a process up to 250 kHz.

The adhesive layer thickness is known by a choice of sputtering time and power according to the respective system geometry.

For example, in the present system geometry, as described below, Cr is sputtered for 6 minutes by two advantageously opposite targets at a pressure between 10-4 and 10-3 mbar, a substrate bias of Ubias = -75 V and a power of about 8 kW in an Ar atmosphere.

The application of a transition layer ensures a smooth transition between the adhesive layer and the DLC layer.

The application of the transition layer shall be carried out by simultaneous removal of carbon from the gas phase in addition to the plasma-assisted evaporation of the adhesive layer components, preferably by a plasma-CVD process using a carbonaceous gas, preferably a hydrocarbon gas, in particular acetylene, as the reaction gas.

Err1:Expecting ',' delimiter: line 1 column 124 (char 123)

To obtain a gradient layer, the proportion of carbon uptake is gradually or continuously increased as the thickness of the transition layer increases during the application of the transition layer until essentially only carbon uptake occurs.

In this process, the diamond-like carbon layer is then produced as a coating by plasma-CVD separation of carbon from the gas phase, using a carbonaceous gas, preferably a hydrocarbon gas, especially acetylene, as the reaction gas, while maintaining a substrate bias voltage on the substrate and maintaining the superimposed magnetic field.

In a preferred embodiment, the reaction gas for carbon separation to form the diamond-like carbon transition and coating layer may contain hydrogen and noble gas, preferably argon or xenon, in addition to the carbon-containing gas, at a pressure in the process chamber of 10-4 to 10-2 mbar.

During the removal of the diamond-like carbon layer, it is preferable to increase the proportion of carbon-containing gas and to reduce the proportion of noble gas, in particular argon.

The stresses applied to the substrate during the process steps of evaporation of the adhesive layer, application of the transition layer and separation of the coating layer from the substrate may be, in particular, during the formation of the transition layer and the coating layer, alternating (AC), DC or modulated (DC) overlapping with AC or pulse, such as unipolar (negative) or bipolar stresses applied to the substrate in the medium frequency range 1 to 10000 kHz, preferably 20 to 250 kHz. The pulse may be symmetrical, for example, sine, sine, sine, sine or right-angled or asymmetrical, such that long and short negative or large and positive positive pulses are applied.

In addition, a longitudinal magnetic field with uniform field lines is preferably set throughout the coating process, with the magnetic field being laterally and/or spatially, continuously or gradually variable.

Preferably, if a DC bias has been used for the application of the adhesive layer, when applying the transition layer, a medium frequency generator is first connected to the support device, which emits its absorption pulses (control of the input power is also possible, but not preferred) in the form of a sine or other bi- or unipolar signal path.Err1:Expecting ',' delimiter: line 1 column 827 (char 826)Err1:Expecting ',' delimiter: line 1 column 135 (char 134)

At or after the time of the medium frequency signal, when using a DC bias to apply the adhesive layer, or after evaporation of the layer thickness required for the adhesive layer, when using a medium frequency bias, a hydrocarbon gas, preferably acetylene, with a gradually or preferably continuously increasing gas flow is introduced into the receptors. Similarly, at or after the time of the medium frequency signal, preferably with a different time delay, the performance of at least one metallic target or Si target is gradually or continuously decreased. This is done to prevent the failure of at least one metallic target or Si target, or at least one target, to fully achieve the high-volume performance of the target, by removing a lightly-determined minimum of the target material from the target, which is otherwise not necessary for the operation of the target. This is done by means of a DLC or a blunt-charger, which is designed to be used in the presence of at least one active target, or a DLC, which is used to prevent the failure of the target from reaching a low level of load.

A substantial contribution to the stabilization of the DLC coating process according to the invention is made by the formation of a longitudinal magnetic field. This is - if not already used in the previous process step for applying the adhesive layer - essentially simultaneous with the switching of the substrate voltage to the medium frequency generator. The magnetic field is formed in such a way that a possible, uniform field line course is given in the process chamber. To this end, electricity is initiated preferably by two electromagnetic coils essentially bordering the process chamber on opposite sides in such a way that an equally directed, mutually amplified magnetic field can be produced on both coils.This results in a nearly uniform distribution of the medium-frequency plasma over larger chamber volumes. Nevertheless, due to different geometries of the parts to be coated or the supporting devices, it can still form secondary plasmas when certain geometric and electromagnetic boundary conditions are met. This can be counteracted by a time and space-varying magnetic field by moving the coil currents together or preferably against each other.These magnetic field adjustments may be made periodically as described, gradually or continuously, and thus avoid the formation of stable secondary plasmas by appropriate coil currents.

Only by using the magnetic field and the resulting significant increase in plasma intensity is it possible, contrary to the state of the art, to achieve a stable CVD process for the separation of pure DLC layers with high separation rates in the range of 0.5 to 5, preferably between 1 and 4 μm/h. In addition to the substrate current, the plasma intensity is also directly proportional to the activation of the magnetic field. Both parameters depend additionally on the size of the surfaces available, covered with a bias.

The growth rate depends not only on the process parameters but also on the loading and the support. In particular, whether the parts to be coated are fixed by rotating 1, 2 or 3 times, on magnetic supporting elements, or clamped or plugged in is important.

In order to further increase the plasma-enhancing magnetic field, in addition to the longitudinal magnetic field (remote field) permeating the entire process chamber, other local magnetic fields - so-called near-fields - may be provided. Particularly advantageous is an arrangement in which, in addition to at least one magnetron magnetic system of at least one target, further permanent magnetic systems, preferably having a similar or the same magnetic effect as at least one magnetron magnetic system, are placed on the walls bordering the plasma chamber. This can either be done for all magnetron and other magnetron systems of the same structure or preferably an inversion of the poles is prevented.

Only by combining the essential features of the inventive process is it possible to produce a layer as described above; only by using plasmas stabilized by magnetic fields and the coordinated use of the substrate voltage is it possible to use the brackets optimized for conventional PVD processes with high packing density and process reliability.

Different methods are used to construct the different layers.

For the separation of a graphitized DLC layer, after the application of the pure DLC layer, the bias voltage is adjusted either gradually or continuously to a value above 2000 V, preferably between 2000 and 2500 V. With increasing voltage, the proportion of C atoms growing in graphite sp2 bond increases. This allows, in a particularly simple way, to give the previously separated pure DLC layer improved glide properties.

In the simplest case, the process can be initiated by maintaining the same parameters as the previous DLC layer by switching one or more metallic or metal carbide layers. However, it has been shown to be advantageous to first either lower the hydrocarbon content in the gas stream, increase the noble gas content, or do both together to avoid targets becoming toxic and thus unstable process states. Furthermore, starting the targets behind closed layers may be advantageous to avoid any drops on the substrates.

Another advantageous way of forming an inverse gradient layer is to add silicon, silicon, oxygen and nitrogen gases, such as mono- and disilane, siloxane, hexamethyl disiloxane, hexamethyl disilazan, dimethyl diethoxyl silane, tetramethyl silane, etc., in addition to or instead of the hydrocarbon gas mentioned, in order to influence the properties of the layer, in particular its hardness and friction coefficient.

The application of a sliding layer as a gradient deck layer can be done either directly on a DLC layer or after application of a metallic or carbide intermediate layer.

For example, for the production of the friction-reducing coating, at least one source used is switched on, similar to the one described above, but with a greater degree of efficiency, to reduce the carbon content of the process gas to 0%. Carbide or metal targets can be used to produce the friction-reducing coating, with the advantage of allowing a higher overall C content for very high layers of resistance. The content of graphite carbon is in turn adjusted by introducing a C-containing reactive target gas, preferably by switching off the gas flow used to produce the C/C-layer, or by temporarily increasing the power of the gas, by means of a steady increase in the vapourization function, and maintained for a certain period of time.

A particularly advantageous layer design is obtained when a thin (0.01 -0.9 μm) carbide such as WC layer is first deposited on the DLC layer. Surprisingly, straight carbide layers have been shown to be particularly well suited as bond mediators on an already deposited DLC layer.

Another preferred embodiment of an inventive DLC smooth layer system is the application of the final smooth layer to a diamond layer deposited, for example, by means of high-current arc discharge or hot filament technique.

The Commission shall:

The above problem is further solved by providing a device to perform the coating process according to one of the characteristic phrases 10 to 26, which includes a vacuum chamber with a pump system to generate a vacuum in the vacuum chamber, substrate supports to accommodate the substrates to be coated, at least one gas supply unit for process gas dosing, at least one evaporator device to provide coating material for evaporation, a light arc generating device to ignite a DC arc, a device to generate a substrate bias voltage and at least one or more magnetic field generating devices to form a distant magnetic field.

Preferably, the magnetic field generating devices shall be formed by at least one Helmholtz coil, preferably a pair of Helmholtz coils.

In the case of Helmholtz coils, the magnetic field or magnetic flux density produced can be controlled both locally and temporally by the current in the coils.

Another way to generate a longitudinal magnetic field is to arrange two magnetrons on opposite sides of the receiver, each of which is additionally connected to at least one electromagnetic coil. The coil is conveniently arranged so that it essentially limits the entire lateral circumference of the magnetron array. The poles of the opposing magnetron magnetic systems are aligned opposite each other, i.e. one north of one system is opposite the south of the other system and vice versa. At the same time, the poles are connected to a current so that the fields of the magnetic sources can be extended to a closed magnetic field according to a helmet-holt arrangement and the magnetic field can be increased during the magnetization of the magnetron.

The device shall also include a device for generating a substrate bias voltage capable of continuously or gradually changing the applied substrate bias voltage and capable of operating at either bipolar or unipolar rates, in particular, the device shall be capable of generating a pulsed substrate bias voltage in the medium frequency range.

The evaporative devices used in the device include sputter targets, in particular magnetron sputter targets, arc sources, thermal evaporators and the like.

The device has the advantage of inductive heating, radiant heating or similar substrate heating to clean the substrate in a heating step before coating, but preferably using plasma ignition.

The device includes, inter alia, a low-voltage arc generation device comprising an ion source with a filament, preferably a refractory filament, in particular of tungsten, tantalum or the like, in an ionization chamber, and an anode and a DC supply. The ion source is connected to the negative pole of the DC supply. Preferably, the positive pole of the DC supply can be connected optionally to the anode or substratum holders, so that a low-voltage arc can be ignited between ions and anode or ions and substrates. The ion source is also similar to the direction of the current flow from the actual process chamber, e.g. through a hole evaporating from a tungsten, T-blast, or similar refractory.

In order to allow a uniform coating process for all sides of the substrates, it is further provided that the substratum supports are mobile and preferably rotate at least one or more axes.

The advantageous combination of medium frequency substratum voltage supply and a Helmholtz coil arrangement, which can also be achieved by side-mounted coils comprising two opposite targets, makes it possible for the first time on an industrial scale to use a stable medium frequency plasma for conducting a DLC process even at low pressures.

The present coating system and the above described process allow for the first time the production of thick pure DLC layers with excellent adhesion, and, if the process parameters are changed, a large part of the previously known plasma processes for the production of metallic carbon or mixtures with other elements such as silicon or F and for the production of multi-layer or simple known layer systems separated by PVD and/or CVD processes can also be carried out.

In addition, DLC sliding layer systems with adjustable sliding and rolling behaviour can be separated.

Further advantages, characteristics and features of DLC sliding layer systems are included in the characteristics sets annexed to the specification.

Further advantages, features and features of the invention are illustrated by the following detailed description of preferred embodiments, based on the attached drawings.The figures in Figure 1 show in a purely schematic way a device in accordance with the invention in cross sectionFigure 2the device in accordance with the invention in Figure 1 in drawingFigure 3Effect of the coil current on the substrate currentFigure 4Process parameter gradient layerFigure 5Process parameter DLC layerFigure 6REM break-up of an invention processDLC layerFigure 7REM break-up of a DLC layerFigure 7Pramma overall processFigure 8Prosesparity DLC processFigure 9Pramma inverse gradient layerFigure 10Pramma 11Pramma inverse layer

Fig. 1 shows a schematic cross-section of the process chamber 1 of a coating system according to the invention. The parts to be coated 2 are mounted on one or more supporting devices 3 which include means for producing at least a simple 4, if necessary, double rotation of the parts. In a particularly advantageous design, the supporting devices 3 are positioned on a carousel 7 which can be rotated additionally around the axis of the system 6.

Gas inlets 8 allow the various process gases, in particular Ar and acetylene, to be introduced into the process chamber by means of appropriate control devices not shown here.

A high vacuum pump stand 9 is flanked by the chamber.

The positive pole of the DC supply 11 may be connected to the carousel 7 or the restraint 3 and the electrically connected parts 2 (heating process) or to the auxiliary anode 13 (setting process or, if necessary, during coating processes) by means of a switch 12 depending on the process step.

The walls of process chamber 1 shall have at least one evaporator source 14, preferably a magnetron or arc evaporator for the application of the adhesive and gradient layer; in another embodiment of the evaporator source 14 not shown here, it may be installed as an anodically connected crucible centrally in the bottom of process chamber 1, where the evaporator material for the production of the transition or gradient layer is transferred to the gas phase by heating through the low-voltage arc 15.

An additional electrical voltage supply 16 is also provided to provide a periodically variable medium frequency voltage in the range 1 to 10 000 kHz, preferably 20 to 250 kHz, to the substrates.

The electromagnetic coils 17 to generate a longitudinal magnetic field permeating the plasma space are located on opposite boundary walls of the process chamber 1 and are fed uniformly by at least one, preferably two, separate DC voltage sources not described herein.

All coating tests were carried out on a process chamber similar to that shown in Figure 1 and having the following dimensions: The chamber height is 920 mm, the diameter 846 mm, the volume 560 1.

As additional measures to enhance or even out the magnetic field and thus the MF plasma 18, magnetic systems 20 for the formation of several nearby magnetic fields 21 may be fitted to the sidewalls 19 of the plasma chamber 1 as an additional measure, whereby magnetic systems with NSN or SNS polarization are alternately arranged, with the advantage of incorporating at least one magnetron magnetic system 22 as shown in FIG. 2, if necessary, to create a magnetic tunnel-like loop-like insertion of the plasma into the process chamber.

Preferably, the magnetic systems 20 are trained as magnetron magnetic systems for near field generation.

The various systems of the coating system are advantageously linked by a process control which makes it possible, in addition to the basic functions of a vacuum coating system (pump control, safety control circuits, etc.), to adapt the various plasma generating systems such as magnetrons with the magnetron supply not described here, ionization chamber 1 and auxiliary anode 13 and, respectively, carousel 7 and DC supply 11, carousel 7 and medium frequency generator 16, as well as the corresponding flow adjustment and, where appropriate, the control of the different coil flows, in a flexible way and to optimise for different processes.

Figure 3 shows the relationship between substrate current and coil current when using Helmholtz coils to build up a magnetic field. It is shown that the substrate current, and thus the plasma density, are directly proportional to the coil current and thus to the magnetic field buildup. This clearly shows the positive effect of a superimposed magnetic field.

Err1:Expecting ',' delimiter: line 1 column 950 (char 949)

In the simplest case, the process can be completed with the evaporation sources switched off, but with the same parameters as in the previous gradient layer, but it has proved advantageous to increase the hydrocarbon content of the gas stream, reduce the noble gas content or, preferably, combine both measures during the removal of the pure DLC layer.

Figures 4 and 5 illustrate the process of individual parameters during the application of the pure DLC layer: after shutting off the Cr targets used, the acetylene ramp started during the gradient layer is steadily increased for about 10 minutes to a flow of about 200-400 sccm, with a constantly adjusted medium frequency supply and constant argon flow. The argon flow is then continuously reduced to a flow of about 0-100 sccm for 5 minutes. The process is completed for the next 55 minutes at constant settings.

Figure 6 shows a raster electron microscopic image of a fracture surface of a DLC layer system of the invention. It is clear that a fine-grained structure is present in the area of the diamond-like carbon cover layer, so that the DLC layer has a polycrystalline character.

Figure 7 shows the overall course of individual process parameters during the application of an inventive DLC layer system.

Figure 8 shows the overall course of individual process parameters during the application of an inventive DLC slide system with a graphitized slide layer: after applying the DLC layer, depending on the desired layer thickness, for example after 33 to 60 minutes of coating time, with otherwise uniform process parameters, the pulsed substrate material is adjusted by means of a voltage ramp to a value between 1500 and 2500 V and then an inlet layer is deposited under constant conditions.

Figure 9 shows the overall process parameters during the application of an inventive DLC slide system with an inverse gradient layer: after applying the DLC layer, depending on the desired layer thickness, for example after 33 to 60 minutes of coating time, the power is released by spraying at least one target behind closed shutters for 10 minutes, with 5 kW behind the shutters, then the shutters are opened and upgraded to 7 kW within about 20 minutes.

Figure 10 shows the process parameters during the application of a gradient layer as a sliding layer, which can be carried out similarly to the transition layer, but also without a metallic adhesive layer.

Figure 11 shows the overall process parameters during the application of an innovative DLC-slip layer system with an H2-rich slide layer. After applying the DLC layer, a methane ramp is started and driven, for example, from 0 to 100 cm3 for about 30 minutes. At the same time, an acetylene ramp is started at 350 cm3 and shut down to 120 cm3 for about 30 minutes.

The following is an example of the implementation of the invention: Examples of processes 1 Heating process

The process chamber is pumped to a pressure of about 10-5 mbar and the process sequence is started. The first part of the process is a heating process to bring the substrates to be coated to a higher temperature and to free the surface of volatile substances. In this process, an Ar-hydrogen plasma is ignited by means of the low-voltage arc between the ionization chamber and an auxiliary anode. Other

Ar-Fluss	75 sccm
Substrat-Bias Spannung [V]	0
Strom des Niedervoltbogens	100 A
Wasserstoff-Fluss	170 sccm
Strom obere Spule	Schwellend zwischen 20 und 10 A
Strom untere Spule	Gegengleich schwellend zwischen 20 und 5 A
Periodendauer zwischen max. und min. Spulenstrom	1.5 min
Heizzeit	20 min

The Helmholtz coils are used to activate the plasma and are cyclically controlled. The current of the upper coil is varied between 20 and 10 A with a periodic duration of 1.5 min, the current of the lower coil varies in the same rhythm between 5 and 20 A.

The substrate heats up and the volatile substances that are disturbing and adhering to the surface are driven into the gas atmosphere where they are sucked out by the vacuum pumps.

The process of brewing

When a uniform temperature is reached, an aeration process is started by pulling the ions from the low-voltage arc onto the substrates by means of a negative bias voltage of 150 V. The alignment of the low-voltage arc and the intensity of the plasma are supported by the Helmholtz coil pair in a horizontal orientation. The following table shows the parameters of the aeration process. Other

Ar-Fluss	75 sccm
Substratspannung	-150 V
Niedervolt-Bogenstrom	150 A

Cr-leaf layer

The application of the Cr-spatter layer is started by activating the Cr-magnetron sputter targets. The Ar gas flow is set to 115 sccm. The Cr-spatter targets are controlled at a power of 8 kW and the substrates are now rotated past the targets for a period of 6 min. The pressure range that is set is then between 10-3 mbar and 10-4 mbar. The sputtering process is supported by switching the low-voltage arc and applying a negative DC bias voltage of 75 V to the substrate.

After half the Cr-sputter time, the low-voltage arc is switched off and the excretion is carried out for the remainder of the Cr-sputter time only with the pre-Cr target active plasma.

Gradient layer

At the end of this time, a plasma is ignited by turning on a sinus generator, acetylene gas is introduced at an initial pressure of 50 μs and the flow is increased by 10 μs every minute.

The sinus plasma generator is set at a frequency of 40 kHz to an amplitude voltage of 2400 V. The generator ignites a plasma discharge between the substrate supports and the housing wall. The Helmholtz coils mounted on the receiver are both activated with a constant current flow of 3 A in the lower coil and 10 A in the upper coil.

DLC coating

When the flow of acetylene has reached 350 cm3, the Ar flow is reduced to 50 cm3.

The table shows the parameters of the sample in an overview: Other

Fluss Argon	50 sccm
Fluss Acetylen	350 sccm
Anregungsstrom obere Spule	10 A
Anregungsstrom untere Spule	3 A
Spannungsamplitude	2400 V
Anregungsfrequenz f	40 kHz

The rate of separation in the coating process will be between 0.5 and 4 μm/h, depending on the surface to be coated in the process chamber.

After the coating time, the sinus generator and gas flow are switched off and the substrates are removed from the process chamber.

The characteristics of the resulting layer are given in the following table. Other

Eigenschaften Beispiel 1
Mikrohärte	ca. 2200 HK
Abscheiderate	1-2µm/h
Haftung	HF1
Widerstand	<10 kΩ
Wasserstoffgehalt	12%
Reibkoeffizient	0.2
Innere Spannung	ca. 2 GPa
Bruchverhalten	Nicht glasig

Example of process 2

Process example 2 provides for an implementation similar to example 1. Unlike example 1, the plasma is generated by a pulse generator.

The table shows the parameters of the second example. Other

Fluss Argon	50 sccm
Fluss Acetylen	350 sccm
Anregungsstrom obere Spule	10 A
Anregungsstrom untere Spule	3 A
Spannungsamplitude	700 V
Anregungsfrequenz f	40 kHz

The resulting coating has a hardness of 25 GPa, a stiffness of HF1 and a friction coefficient of 0.2. Other

Eigenschaften Beispiel 2
HK	ca. 2400
Abscheiderate	ca. 1.5 km/h
Haftung	HF1
Widerstand	>500kΩ
Wasserstoffgehalt	13%
Reibkoeffizient	0.2
Innere Spannung	Ca. 3 GPa

Example of process 3

Process example 3 provides for a similar implementation to example 1. Unlike example 1, the plasma is excited by a unipolar pulse voltage, the parameters of the experiment are shown in the following table. Other

Fluss Argon	50 sccm
Fluss Acetylen	350 sccm
Anregungsstrom obere Spule	10 A
Anregungsstrom untere Spule	3 A
Spannungsamplitude	1150 V
Anregungsfrequenz f	30 kHz

The resulting coating has the properties described in the following table. Other

Eigenschaften Beispiel 3
Mikrohärte	> 2500 HK
Abscheiderate	ca. 1.8 µm/h
Haftung	HF1
Widerstand	> 1 kΩ
Wasserstoffgehalt	12-16%
Reibkoeffizient	0.2
Innere Spannung	ca. 2 GPa

Example of process 4

In comparison to process example 1, in example 4 a process was performed without support by a longitudinal magnetic field. The current flowing through the two coils was reduced to a value of 0 A. The table shows the process parameters.

Fluss Argon	50 sccm
Fluss Acetylen	350 sccm
Anregungsstrom obere Spule	0 A
Anregungsstrom untere Spule	0 A
Spannungsamplitude	2400 V
Anregungsfrequenz f	40 kHz

A plasma is formed which is stable in comparison to example 1 only at higher pressures than in example 1, is distributed inhomogeneously over the process chamber and is very strongly affected by geometric effects. Therefore, it is inhomogeneous in the process chamber and due to the lower separation rate at the process pressure compared to example 1. At the targeted process pressures, a plasma formation was not possible without the use of a second plasma source such as a target or the coupling of the filament. Only by the use of Helmholtz coils could the plasma be stabilized in the process chamber and a homogeneous separation over the height of the process chamber be achieved. Other

Eigenschaften Beispiel 4
HK	Inhomogen 1200 - 2500
Abscheiderate	Inhomogen
Haftung	Nicht bestimmbar
Widerstand	Inhomogen

Sliding layer systems

In the following, different sliding layers have been applied to the DLC layers described above to produce a layer system according to the invention, taking care that the process, which includes all plasma pre-treatment and coating steps, is run continuously without interruption of the vacuum to achieve optimal layer adhesion.

Table 5 shows various process examples with a graphitized coating. Other

DLC-Schichtsystem Beispiel	wie 1 aber Spannungsampl. 1000V	2	3
Fluss Argon	50 sccm	50 sccm	50 sccm
Fluss Acetylen	350 sccm	350 sccm	350 sccm
Anregungsstrom obere Spule	10 A	10 A	10 A
Anregungsstrom untere Spule	3 A	3 A	3 A
Substrat-Spannungsamplitude	2400 V	2400 V	2400 V
Rampe Spannung	15 min	25 min	15 min
Anregungsfrequenz f	40 kHz	40 kHz	30 kHz
Anregungstyp	AC-Sinus	bipolarer Puls	unipolarer Puls

Table 6 shows various possibilities for the formation of a sliding layer, such as a closing gradient layer (No. 8), an inverse gradient layer (No. 9), or a hydrogen rich C layer (No. 10). Other

DLC-Schicht Nr.	3	2	2
Fluss Argon 1	30 sccm	50 sccm	50 sccm
Fluss Argon 2	30 (100) sccm	-	-
Rampe Argon	0 (10)min	-	-
Fluss Acetylen 1	0 sccm	350 sccm	350 sccm
Fluss Acetylen 2	250 sccm	180 sccm	150 sccm
Rampe Acetylen	15 min	20 min	20 min
Fluss Methan 1	-	-	0 sccm
Fluss Methan 2	-	-	150 sccm
Rampe Methan	-	-	20 min
Leistung Cr-Target 1	8 kW	7 kW	-
Leistung Cr-Target 2	7 kW	-	-
Rampe Cr-Target	20 min	30 min	-
Anregungsstrom obere Spule	10 A	10 A	10 A
Anregungsstrom untere Spule	3 A	3 A	3 A
Substrat-Spannungsamplitude	2400 V	700 V	1150 V
Anregungsfrequenz f	40 kHz	40 kHz	30 kHz
Anregungstyp	AC-Sinus	bipolarer Puls	unipolarer Puls

The acetylene ramp can also be started with a linear delay of 5-10 min after the Cr targets are switched on. This is particularly advantageous when DLC and a slide layer are applied in different process chambers or coating systems.

The graphite component can also be increased by co-sputtering of carbide targets, e.g. WC and/or graphite targets, simultaneously or also with delay.

The properties of the corresponding DLC layers are shown in Table 8 and Table 8 . Other

VersuchNr.
Haftung	HF 1	HF 1	HF 1
Widerstand	< 100 kΩ	< 100 kQ	< 100 kΩ
Reibkoeffizient	ca. 0.10	ca. 0.15	ca. 0.12

Table 9 shows the following: Other

VersuchNr.	8	9	10
Haftung	HF 1	HF 1	HF 1
Widerstand	< 1 kΩ	< 1 kΩ	< 100 kΩ
Wasserstoffgehalt	n.g.	n.g.	> 30 atom%
Reibkoeffizient	ca. 0.08	ca. 0.07	ca. 0.13

List of reference marks

1.process chamber 2.coating parts 3.holding device 4.single rotation 5.double rotation 6.plant axis 7.carousel 8.gas inlet 9.pump 10.ion source 11.continuous voltage supply 12.switch 13.auxiliary anode 14.vapor source 15.low-voltage arc 16.voltage supply 17.electromagnetic S18.MF-plasma 19.sidebar 20.magnetic systems 21.near field 22.magnetron magnetic systems

Claims (42)

1. A layer system for wear protection, corrosion protection and improvement of slip properties and the like, with an adhesive layer to be applied to a substrate, a transition layer to be applied to the adhesive layer and a diamond-like carbon top layer, characterised by the layer system comprising at least one element from the group containing the elements of subgroups 4, 5 and 6 and silicon, the transition layer comprising carbon and at least one element from the group containing the elements of subgroups 4, 5 and 6 and silicon, and the top layer comprising essentially diamond-like carbon, with a layer system hardness of at least 15 G, preferably at least 20 GF, a tensile strength of at least 3 Pa and a binding strength of at least 3 Pa.
2. Layer system according to characteristic 1, characterised by the transition layer being a continuous or gradually changing composition of a single or multilayer gradient layer with increasing carbon content and decreasing content of at least one element from the substrate from the group containing the elements of subgroups 4, 5 and 6 and silicon.
3. A layered system according to one of the previous characteristics, characterised by a higher thickness of the top layer compared to the adhesive layer and the transition layer.
4. Layer systems according to one of the previous characteristics, characterised by the addition of hydrogen and unavoidable impurities to the transition and/or top layer, which include unavoidable impurities in the form of noble gases, in particular argon and xenon.
5. Layered system according to characteristic 4, characterised by the roof layer containing exclusively carbon or carbon and hydrogen.
6. Layer system according to the characteristic 4, characterised by the deck layer containing a hydrogen content of 5 to 30% atomic percent, preferably 10 to 20% atomic percent.
7. A layer system according to one of the above characteristics, characterised by the presence of at least one element from the group containing the elements of subgroups 4, 5 and 6 being titanium and/or chromium.
8. A layer system according to one of the above characteristics, characterised by the adhesive layer and the transition layer each having a thickness of 0,05 μm to 1,5 μm, preferably 0,1 μm to 0,8 μm.
9. A layered system according to one of the previous characteristics, characterised by the thickness of the cover layer being between 0,5 μm and 20 μm, preferably between 1 μm and 10 μm.
10. A layer system according to one of the previous characteristics, characterised by the diamond-like carbon roof layer having a fine-grained layer structure with a roughness value Rz < 0.8, preferably Rz < 0.5.
11. A process for the production of a layer system, in particular one of the characteristics 1 to 10, on a substrate, characterised by the process involving: Other

    (a) Insert the substrate into a vacuum chamber and pump until a vacuum is reached at a pressure of less than 10-4 mbar, preferably 10-5 mbar.

    (b) Cleaning of the substrate surface

    (c) plasma-assisted evaporation of the adhesive layer on the substrate

    (d) Applying the transition layer to the adhesive layer by simultaneous plasma-assisted evaporation of the adhesive layer components and carbon separation from the gas phase

    (e) Applying the diamond-like carbon layer to the transition layer by plasma-assisted carbon separation from the gas phase;

    at least during the steps (c), (d) and (e) a stress is applied to the substrate and at least during the steps (d) and (e) the plasma is stabilized by a magnetic field.
12. The method described in clause 11 is characterised by the cleaning of the substrate surface by a heating and/or etching step.
13. A process according to the specification 12 characterised by the heating step being radiant heating, inductive heating and/or electron bombardment.
14. The method described in paragraph 13 is characterised by the electron firing by igniting a low voltage arc and simultaneously applying a continuous, AC or AC superimposed bias voltage, such as a pulsed positive substrate bias voltage.
15. The method described in paragraph 10 is characterised by the etching step being carried out by ionates, using a noble gas, preferably argon, and/or hydrogen as the process gas to ignite a low-voltage arc and applying a continuous negative substrate bias voltage to the substrate.
16. The method described in paragraph 10 is characterised by the etching step being carried out by ionic acids with a noble gas, preferably argon, and/or hydrogen as the process gas, by applying an AC or AC superimposed bias voltage, such as a pulsed, preferably medium frequency substrate bias voltage.
17. Processes according to one of the characteristic phrases 10 to 16 characterised by the evaporation of the adhesive layer by plasma CVD processes, PVD processes, in particular arc evaporation, cathodic sputtering, evaporation from a crucible by means of a low-voltage arc, preferably by means of an ion plating process.
18. The method described in paragraph 17 is characterised by the evaporation of the adhesive layer being supported by an additional low-voltage arc discharge and by the application of a negative stress to the substrate.
19. The method described in paragraph 17 is characterised by the evaporation of the adhesive layer by an additional pulsed substrate bias voltage, preferably supporting an AC or AC overlapping bias voltage, such as in particular a pulsed substrate bias voltage in the mid-frequency range from 1 to 20,000 kHz, preferably 20 to 250 kHz.
20. A process according to one of the following characteristic phrases 10 to 19: a noble gas or a noble gas/hydrogen mixture, preferably argon/hydrogen mixture, is introduced into the vacuum chamber to ignite a plasma.
21. Process according to one of the characteristics 10 to 20 characterised by the formation of the transition layer by the simultaneous evaporation of at least one element from the group containing the elements of subgroups 4, 5 and 6 and silicon, following a process according to one of the characteristics 17 to 20 and plasma-assisted carbon separation from the gas phase, using a carbonaceous gas, preferably a hydrocarbon gas, in particular acetylene, as an additional reaction gas.
22. The method according to the characteristic rule 21 is characterised by a gradual or continuous increase in the proportion of carbon uptake as the thickness of the transition layer increases.
23. A process according to one of the characteristic phrases 10 to 22 characterised by the production of the diamond-like carbon layer forming the cover layer by plasma CVD separation of carbon from the gas phase using a carbonaceous gas, preferably a hydrocarbon gas, in particular acetylene, as the reaction gas.
24. A process according to one of the following formulae 21 or 23 characterised by the reaction gas for the separation of carbon containing hydrogen and/or noble gas, preferably argon and/or xenon, in addition to the carbon gas.
25. The method according to the characteristic principle 24 is characterised by the increase in the proportion of the carbonaceous gas and/or the decrease in the proportion of the noble gas, in particular argon, during the separation of the diamond-like carbon backbone.
26. A process according to one of the characteristic phrases 21 to 25 characterised by the application of a unipolar or bipolar substrate bias voltage to the substrate pulsed in a medium frequency range from 1 to 10 000 kHz, preferably 20 to 250 kHz.
27. The method described in paragraph 26 is characterised by the substrate bias voltage being sinusoidal or pulsed in such a way that long negative and short positive pulse times or large negative and small positive amplitudes are applied.
28. "Technology" according to the General Technology Note for the "development" or "production" of "materials" specified in 2B201.a. to 2B201.b.
29. Process according to one of the characteristic phrases 10 to 28, characterised by the application of the adhesive layer and/or transition layer and/or coating layer of diamond-like carbon at a pressure of 10-4 mbar to 10-2 mbar
30. Device for coating one or more substrates, in particular to perform the coating process according to one of the characteristic phrases 10 to 29, with a vacuum chamber (1) with a pump system (9) to generate a vacuum in the vacuum chamber (1), substrate supports (3) to receive the substrate to be coated, at least one gas supply unit (8) to add process gas, at least one evaporator device (14) to provide coating material for evaporation, a light arc generator (10, 143) to ignite a DC low voltage arc, a device (16) to generate a substrate bias voltage and at least one or more magnetic field generators (17) to form a magnetic field.
31. A device according to the specification 30 characterised by the magnetic field generating device (17) being formed by at least one Helmholtz coil.
32. A device according to the characteristic rule 31, characterised by the fact that the Helmholtz coil is controllable with respect to the magnetic flux density that can be generated.
33. "Technology" according to the General Technology Note for the "development" or "production" of equipment specified in 1C001.a. or 1C001.b.
34. "Software" specially designed or modified for the "development", "production" or "use" of equipment specified in 1C001.b., 1C001.c., 1C001.d., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C. and 1C.
35. Device according to one of the characteristic phrases 30 to 34, characterised by the fact that the evaporator device (14) is detachable from the rest of the process chamber (1).
36. Equipment according to one of the characteristic phrases 30 to 35 characterised by the fact that the device continues to include substrate heating in the form of induction heating, radiation heating or the like.
37. A device according to one of the characteristic phrases 30 to 36 characterised by the fact that the arc generating device (10, 13) comprises an ion source (10) and an anode (13) and a DC supply (11) with the ion source (10) connected to the negative pole of the DC supply (11).
38. A device according to the specification 37 characterised by the positive pole of the DC supply (11) being optional for connection to the anode (13) or to the substratum supports (3).
39. "Software" specially designed or modified for the "development", "production" or "use" of equipment specified in 1C001.b., 1C001.c., 1C001.d., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C001.e., 1C. and 1C.
40. A device according to one of the characteristic phrases 30 to 39 characterised by the mobility of the substrate supports (3), preferably by rotation about at least one or more axes.
41. A device according to one of the characteristic sets 30 to 40 characterised by the addition of permanent magnets (20) to generate a near-field magnetic field.
42. The device described in 41 is characterised by the addition of permanent magnets (20) in a ring around the vacuum chamber (1), preferably with alternating polarity, and in particular by the formation of a magnetron electron trap.