WO2013156107A1

WO2013156107A1 - Coating containing si-dlc, dlc, and me-dlc, and a method for producing coatings

Info

Publication number: WO2013156107A1
Application number: PCT/EP2013/000956
Authority: WO
Inventors: Dieter Hofmann
Original assignee: Amg Coating Technologies Gmbh
Priority date: 2012-04-20
Filing date: 2013-03-28
Publication date: 2013-10-24
Also published as: DE102012007763A1

Abstract

The invention relates to a workpiece which comprises a main part, one or more intermediate layers if required, and a cover layer which contains Si-DLC, DLC, one or more types of Me-DLC, and 2.5 to 20 atm.% of hydrogen, Me being selected from the group comprising Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Ni and W; the cover layer having a hardness of 15 to 50 GPa; the cover layer consisting of partial volumes of a size between 40 x 40 x 40 nm³ and 200 x 200 x 200 nm³, and each partial volume having an average Si-content of 2.5 to 30 atm.% and an average Me-content of between 2.5 and 30 atm.%. A method for PVD-coating workpieces comprises one or more steps S¹ to S_N, where N = 1, 2 or 3, in which in step S_N, a cover layer containing Si-DLC, DLC, Me-DLC and hydrogen, where Me is selected from the group comprising Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Ni and W, is deposited using one or more simultaneously-operated magnetron cathodes with the same or differing targets, with one or more targets containing 20 to 100 atm.% of silicon, one or more targets containing 20 to 100 atm.% of carbon, and one or more targets containing 20 to 100 atm.% of Me, and the deposition being carried out in an atmosphere that has a nominal hydrogen content of less than 30 atm.%.

Description

Coating containing Si-DLC, DLC and Me-DLC and process for producing coatings

The present invention relates to a workpiece comprising a base body and a cover layer containing Si-DLC, DLC, one or more types of Me-DLC and 2.5 to 20 atomic% hydrogen, wherein Me is selected from the group comprising Ti, V , Cr, Zr, Nb, Mo, Hf, Ta, Ni, W, and the cover layer has a hardness of 15 to 50 GPa.

The use of tribological layers of Si-DLC, DLC or Me-DLC is known in the art.

DE 100 18 143 B3 describes a layer system and a method for its production, wherein the layer system comprises a cover layer of substantially diamond-like carbon (DLC) having a hardness of at least 15 GPa and an adhesive strength of 3 HF or better. In addition to the cover layer, the layer system comprises an adhesion layer and a transition layer, the adhesion layer and possibly the transition layer containing at least one element of the 4th, 5th or 6th subgroup and / or silicon. The cover layer is preferably produced by means of plasma CVD deposition from a carbon-containing gas, such as acetylene, and has a hydrogen content of 5 to 30 atomic%.

EP 87 836 discloses a DLC layer system with a 0, l-49, l% share of metallic components, which is deposited, for example by means of sputtering.

DE 43 43 354 A1 describes a method for producing a multilayer Ti-containing layer system with a hard material layer of titanium nitrides titanium carbides and titanium borides and a friction-reducing C-containing surface layer, wherein the Ti and N content is progressively reduced in the direction of the surface.

A pulsed plasma jet uses the method described in US 5,078,848 for the preparation of DLC layers. Due to the directed particle radiation from a source with a small outlet cross-section, however, such processes are only conditionally suitable for the uniform coating of larger areas.

Various CVD processes or Si-DLC / DLC mixed layers produced by such processes are described in the following documents: EP-A-651 069 describes a friction reducing wear protection system of 2-5000 alternating DLC and Si-DLC layers. A process for the deposition of a-DLC layers with an Si intermediate layer and subsequent a-SiC: H transition zone for improving the adhesion is described in EP 600 533. Also EP 885 983 and EP 856 592 describe various processes for producing such layers. In EP 885 983, for example, the plasma is fed with a DC-heated filament and the substrates with negative DC voltage or frequencies between 30-1000 kHz applied.

US Pat. No. 4,728,529 describes a method for the deposition of DLC using an HF plasma, in which the layer formation takes place in a pressure range between 10 ^" and 1 mbar from an oxygen-free hydrocarbon plasma, to which noble gas or hydrogen is added as required.

The process described in DE-C-195 13 614 uses a bipolar substrate voltage having a shorter positive pulse duration in a pressure range between 50-1000 Pa. This layers are deposited in the range of 10 nm to 10 μηι layer thickness and a hardness between 15-40 GPa.

A CVD method with substrate voltage generated independently of the coating plasma is described in DE-A-198 26 259, whereby preferably bipolar, but also other periodic changed substrate voltages are applied.

Some of the tribological Si-DLC, DLC and Me-DLC coatings known in the prior art have a high hardness of over 15 GPa and a sliding friction coefficient μ of less than 0.2. However, the wear resistance and thus the mileage of equipped with the known DLC layers components such as gears and parts for drives, engine components from an internal combustion engine, transmission parts from an automotive transmission, connecting rods, gear parts, gears, shafts, bearings, bearings, ball bearings, Needle roller bearings, piston rings, piston pins, cylinder liners, parts of fuel injection device eg For the direct injection of diesel or gasoline for automotive engines, parts of the valve train of a car engine, bucket tappets, drag lever, rocker arms, valve lifters, Lmearführungen, closures for automotive doors, bushings not always the high demands of the automotive and aviation industry.

In addition to hardness, sliding friction and wear resistance of the coating, the life and the frictional resistance of the above components are determined by the complex interaction of the coating with an optionally present counter body and in particular with lubricants or operating materials, such as mineral or synthetic engine and transmission oil or diesel. A large number of the lubricants and operating materials used contain additives which react with the topmost atomic layers of the coating or their abrasion and form amorphous or microcrystalline compounds. Depending on the respective component type, the characteristic operating parameters, such as the temperature and the optionally used lubricant, it is necessary to adjust the thermal and chemical properties of the coating in a targeted manner.

Accordingly, the present invention has the object to provide components or workpieces with a tribological coating, which in addition to the required, determined in standardized measurement under laboratory conditions mechanical properties such as hardness, sliding friction and wear resistance, chemical and thermal properties, the long life with favorable Operating parameters, such as ensure low friction losses.

This object is achieved by a workpiece comprising a base body, optionally one or more intermediate layers and a cover layer which contains Si-DLC, DLC, one or more types of Me-DLC and 2.5 to 20 atom% of hydrogen, wherein Me is selected from the group comprising Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Ni, W; the topcoat has a hardness of 15 to 50 GPa; the top layer consists of partial volumes of the size 40 × 40 × 40 nm to 200 × 200 × 200 nm and each partial volume has an average Si content of 2.5 to 30 atomic% and an average Me content of 2.5 to 30 atom -% Has.

Further embodiments of the workpieces according to the invention are characterized in that:

- Each sub-volume has an Si content of 5 to 25 atomic%, preferably 8 to 20 atomic% and a Me content of 5 to 25 atomic%, preferably 10 to 20 atomic%;

- The top layer has a hydrogen content of 5 to 18 atomic%, preferably 5 to

15 atomic%, and especially 5 to 10 atomic%;

- The cover layer has a thickness of 0.4 to 5.0 μιη, preferably 0.6 to 3.0 μηι, and in particular 0.8 to 2.0 μπι;

- The top layer has a hardness HU _p iast of 20 to 40 GPa and preferably 25 to 40 GPa;

- The cover layer has a coefficient of friction μ of 0.05 to 0.20, preferably 0.05 to 0.15, and in particular 0.05 to 0.1; the cover layer according to Kalotest with a suspension of Al ₂ 0 ₃ powder in glycerol a wear coefficient of 0.5 x 10 ^"15 to 4.0x 10 ^{" 15} m ³ / (Nm), preferably 0.5 x 10 ^"15 to 2 , 5 x 10 ^"15 m ³ / (Nm), and in particular 0.5 x 10 ^" ' ⁵ to 1.5 x 10 ^"15 m ³ / (Nm); the topcoat has an adhesive strength HF1 to HF4, preferably HF1 to HF3, and in particular HF1 to HF2 measured by means of a Rockwell A test for cemented carbide bodies and otherwise by Rockwell C test; the topcoat has a content of from 0.01 to 6.0 atomic% of an additive selected from boron, sulfur and mixtures thereof;

Me tungsten is; the cover layer comprises one or more triple layers and each of the triple layers consists of a first layer Si-DLC, a second layer DLC and a third layer Me-DLC and the first, second and third layers are arranged in an arbitrary fixed periodic order; each of the first, second and third layers independently has a thickness of 0.1 to 20 nm, preferably 1 to 10 nm, and more preferably 1 to 5 nm; the silicon content in the cover layer increases with increasing distance from the base body; the surface energy of the cover layer measured by wetting the cover layer with water in accordance with DIN 55660 or ASTM D7334-08 is 35 to 60 mN / m, preferably 40 to 60 mN / m and in particular 45 to 60 mN / m; the topcoat contains 2 to 10 atomic% nitrogen; the X-ray diffraction spectra of the cover layer have no intensity maxima for crystalline phases of tungsten carbide or silicon carbide; the cover layer has a glassy morphology; the cover layer has no column structures detectable in electron microscopic images; the workpiece comprises an adhesion layer of Ti, V, Cr, CrN, Zr, Nb, Mo, Hf, Ta, Si or Ni arranged between the cover layer and the base body and adjacent to the base body; the workpiece comprises a first SiCx, MeCx or WCx intermediate layer arranged between the cover layer and the main body or the adhesion layer and adjacent to the main body or to the adhesion layer, and optionally a second DLC mediator layer disposed between the first intermediate layer and the cover layer and adjacent to the first intermediate layer; Si-DLC or Me-DLC, in particular of W-DLC, and in the intermediary layers the following material pairings are present:

wherein Me-DLC is preferably carried out as W-DLC; a valve disposed between the topsheet and the Grimdkörper or the adhesive layer and adjacent to the base body or to the adhesion layer first layer system of one or more double layers of silicon carbide (SiC _x / WC _X), (SiC _x / MeC _x), (WC _X / SiC _x) or (MeCx / SiCx) and optionally a second layer system arranged between the cover layer and the first layer system and adjacent to the first layer system, wherein the second layer system comprises one layer or two layers selected from SiC _x , (SiC _x / DLC), (SiC _x / Si-DLC), (SiC _x / Me-DLC), in particular (SiC _x / W-DLC), or MeC _x , (MeC _x / DLC) , (MeC _x / Si-DLC), (MeC _x / Me-DLC), in particular (MeC _x / W-DLC), where MeC _{x is} preferably in the form of WC _X , and in the layer systems the following material pairings are present:

where n is an integer greater than or equal to 1 and Me-DLC is preferably carried out as W-DLC and MeCx preferably as WCx; a first layer system consisting of one or more double layers of (SiC _x / DLC), (SiC _x / Si-DLC), (SiC _x / Me-DLC) arranged between the cover layer and the main body or the adhesion layer and adjacent to the main body or to the adhesion layer. , in particular (SiC _x / W-DLC) or (MeC _x / DLC), (MeC _x / Si-DLC), (MeC _x / Me-DLC), in particular (MeC _x / W-DLC) and optionally one between the Cover layer and the first layer system arranged and adjacent to the first layer system second layer system, wherein the second layer system selected two layers from (SiCx / DLC), (SiC _x / Si-DLC), (SiC _x / Me-DLC), in particular (SiC _x / W-DLC) or (MeCx / DLC), (MeC _x / Si-DLC), (MeC _x / Me-DLC), in particular (MeCx / W-DLC) and in the layer systems the following material pairings are present: first layer system second layer system

nx (SiC _x / DLC) SiCx DLC

nx (SiC _x / DLC) SiCx Si-DLC

nx (SiC _x / DLC) SiCx Me-DLC

nx _(x SiC / Si-DLC) SiCx DLC

nx _(x SiC / Si-DLC) SiC _x Si-DLC

n _(x SiC / Si-DLC) SiCx Me-DLC

nx (SiC _x / Me-DLC) SiCx DLC

n x (SiCx / Me-DLC) SiCx Si-DLC

n (SiC _x / Me-DLC) SiCx Me-DLC

nx (SiC _x / DLC) MeC _x DLC

nx (SiC _x / DLC) MeC _x Si-DLC

nx (SiCx / DLC) MeC _x Me-DLC

n (SiC _x / Si-DLC) MeC _x DLC

nx _(x SiC / Si-DLC) MeC _x Si-DLC

nx _(x SiC / Si-DLC) MeC _x Me-DLC

nx (SiC _x / Me-DLC) MeC _x DLC

nx (SiC _x / Me-DLC) MeC _x Si-DLC

nx (SiC _x / Me-DLC) MeC _x Me-DLC

nx (MeC _x / DLC) SiC _x DLC

nx (MeC _x / DLC) SiCx Si-DLC

nx (MeC _x / DLC) SiCx Me-DLC

nx (MeC _x / Si-DLC) SiC _x DLC

nx (MeC _x / Si-DLC) SiCx Si-DLC

n (MeC _x / Si-DLC) SiC _x Me-DLC

nx (MeC _x / Me-DLC) SiC _x DLC nx (MECX / Me-DLC) SiC _x Si-DLC

n x (MeCx / Me-DLC) SiCx Me-DLC

nx (MeC _x / DLC) MeC _x DLC

n (MeC _x / DLC) MeC _x Si-DLC

nx (MeC _x / DLC) MECX Me-DLC

nx (MeCx / Si-DLC) MeC _x DLC

n (MeCx / Si-DLC) MeCx Si-DLC

nx (MeCx / Si-DLC) MeC _x Me-DLC

nx (MeC _x / Me-DLC) MECX DLC

nx (MeC _x / Me-DLC) MeC _x Si-DLC

nx (MeC _x / Me-DLC) MeCx Me-DLC where n is an integer greater than or equal to 1 and Me-DLC is preferably designed as W-DLC and MeCx preferably as WCx; a first layer system consisting of (Si-DLC / SiCx), (Si-DLC / MeCx), preferably (Si-DLC / WC), arranged between the cover layer and the main body or the adhesion layer and adjacent to the main body or to the adhesion layer _X ) or (Me-DLC / SiCx), in particular (W-DLC / SiCx), (Me-DLC / MeC _x ), in particular (W-DLC / WCx) or (DLC / SiC _x ), (DLC / MeC _x ), preferably (DLC / WCx) and optionally a second layer system arranged between the cover layer and the first layer system and adjacent to the first layer system, the second layer system comprising two layers selected from (SiC _x / DLC), (MeC _x / DLC), (SiC _x / Si-DLC), (MeC _x / Si-DLC), (SiC _x / Me-DLC), in particular (SiC _x / W-DLC) or (MeC _x / Me-DLC), in particular (MeC _x / W-DLC) and in the layer systems the following material pairings are present: first layer system second layer system

nx (Si-DLC / SiC _x) SiC _x DLC

nx (Si-DLC / MeC _x) SiCx DLC

nx (Si-DLC / SiC _x) Me C _x DLC

n (Si-DLC / MeCx) MeCx DLC nx (Si-DLC / SiC _x) SiC _x Si-DLC nx (Si-DLC / MeC _x) SiC _x Si-DLC nx (Si-DLC / SiC _x) Me C _x Si-DLC nx (Si-DLC / MeC _x ) MeC _x Si-DLC nx (Si-DLC / SiC _x ) SiCx Me-DLC nx (Si-DLC / MeC _x ) SiC _x Me-DLC nx (Si-DLC / SiC _x ) MeC _x Me-DLC nx (Si -DLC / MeC _x) Me C _x Me-DLC nx (Me-DLC / SiC _x) SiCx DLC nx (Me-DLC / MeC _x) SiCx DLC nx (Me-DLC / SiC _x) Me C _x DLC nx (Me-DLC / MeC _x ) MeC _x DLC nx (Me-DLC / SiC _x ) SiC _x Si-DLC nx (Me-DLC / MeC _x ) SiCx Si-DLC nx (Me-DLC / SiC _x ) MeC _x Si-DLC nx ( Me-DLC / MeC _x ) MeC _x Si-DLC nx (Me-DLC / SiC _x ) SiCx Me-DLC nx (Me-DLC / MeC _x ) SiCx Me-DLC nx (Me-DLC / SiC _x ) MeC _x Me -DLC nx (Me-DLC / MeC _x) Me C _x Me-DLC nx (DLC / SiC _x) SiCx DLC nx (DLC / MeC _x) SiCx DLC nx (DLC / SiC _x) MECX DLC nx (DLC / MeC _x) MeC _x DLC nx (DLC / SiC _x ) SiC _x Si-DLC nx (DLC / MeC _x ) SiC _x Si-DLC nx (DLC / SiC _x ) MeC _x Si-DLC nx (DLC / MeC _x ) MeC _x Si DLC nx (DLC / SiC x) SiCx Me-DLC nx (DLC / MeC _x) Me-DLC SiCx nx (DLC / SiC _x) Me C _x Me-DLC

nx (DLC / MeC _x ) MeC _x Me-DLC where n is an integer greater than or equal to 1 and Me-DLC is preferably carried out as W-DLC and MeCx preferably as WCx; the workpiece is a layer system consisting of one or more double layers of (Si-DLC / DLC), (Si-DLC / Me-DLC), which is arranged between the cover layer and the main body or the adhesion layer and adjacent to the main body or to the adhesion layer, in particular (Si-DLC / W-DLC) or (DLC / Si-DLC), (DLC / Me-DLC), in particular (DLC / W-DLC) or (Me-DLC / Si-DLC), in particular (W-DLC / Si-DLC ), (Me-DLC / DLC), in particular (W-DLC / DLC) and optionally an intermediate layer of DLC, Si-DLC or Me-DLC, in particular of W-DLC, arranged between the cover layer and the layer system and adjacent to the layer system and in the layer system and the mediator layer the following material pairings are present:

Layer system mediator layer

n x (Si-DLC / DLC)

n x (Si-DLC / DLC) Si-DLC

n (Si-DLC / DLC) Me-DLC

n x (Si-DLC / Me-DLC)

n x (Si-DLC / Me-DLC) Si-DLC

n (Si-DLC / Me-DLC) DLC

n x (DLC / Si-DLC)

n x (DLC / Si-DLC) DLC

n x (DLC / Si-DLC) Me-DLC

nx (DLC / Me-DLC)

nx (DLC / Me-DLC) DLC

n x (DLC / Me-DLC) Si-DLC

n x (Me-DLC / Si-DLC)

nx (Me-DLC / Si-DLC) DLC nx (Me-DLC / Si-DLC) Me-DLC

nx (Me-DLC / DLC)

nx (Me-DLC / DLC) Si-DLC

n x (Me-DLC / DLC) Me-DLC where n is an integer greater than or equal to 1 and Me-DLC is preferably designed as W-DLC;

the workpiece comprises a layer of DLC disposed between the cover layer and the base body and adjacent to the cover layer; the base body is made of a material selected from steel, steel alloys, titanium, titanium alloys, aluminum, aluminum alloys, magnesium, magnesium alloys, copper, copper alloys, ceramic material, hard metal, tungsten, tungsten alloys, tantalum, tantalum alloys, nickel, nickel alloys, silicon, silicon compounds, bronze, Plastic or a mixture of these materials; and

The workpiece is an engine part of an internal combustion engine, a transmission part of an automotive transmission, a connecting rod, a gear part, a gear, a shaft, a bearing shell, a rolling bearing, a ball bearing, a needle bearing, a piston ring, a piston pin, a cylinder liner, a part a fuel injection device, for example for the direct injection of diesel or gasoline for automotive engines, a part of the valve train of a car engine, a bucket tappet, a rocker arm, a rocker arm, a valve lifter, a Linearfuhrung, a locking door for automobile doors, a sliding bushing or a solar cell.

Diamond-like carbon or DLC and methods for depositing coatings from DLC by CVD and / or PVD are well known in the art. In DLC layers, the carbon atoms are arranged in a three-dimensional irregular lattice with a large portion of the carbon atoms sphybridized and each covalently bonded to four adjacent carbon atoms.

In the context of the invention, the abbreviations "SiCx", "MeCx" and "WCx" designate layer materials which have a metallic or carbidic character and in particular predominantly of silicon or silicon carbide (SiC), selected from a metal consist of Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Ni or metal carbide (MeC), or of tungsten or tungsten carbide (WC). In pure SiC, MeC or WC, the stoichiometric ratio of Si, Me or W to C is exactly 1 atomic% to 1 atomic%. The layer materials referred to in the present application as "SiCx", "MeCx" and "WCx" generally have a stoichiometry different from pure SiC, MeC or WC, where X is the ratio of the carbon fraction relative to the silicon, metal or WC Indicates tungsten content and is typically in the range 0.1 <X <2.0, ie for each atomic% of silicon, metal or tungsten, the layers contain 0.1 to 2.0 atomic% carbon. Such layers generally consist of a mixture of several phases, for example of SiC, MeC or WC crystallites, which in a matrix of metallic silicon, metal or tungsten (X <1) or a matrix of graphitic, sp -hybridized or possibly diamond-like, sp ³ -hybridized carbon (1 <X <2) are embedded. According to the invention, "graded" SiCx, MeCx or WCx layers are additionally provided, in which X, ie the stoichiometric ratio of carbon to silicon, metal or tungsten, is varied by targeted modification of the deposition parameters in such a way that it steadily increases or decreases. In the context of the invention, SiCx, MeCx or WCx layers with increasing X or carbon content are primarily provided in order to provide a more or less continuous transition to a subsequently deposited covering layer of Si-DLC or DLC or Me-DLC mediator layers , Such graded SiCx, MeCx, or WCx layers reduce thermal mismatch and improve adhesion.

Hereinafter, the term "Me-DLC" refers to diamond-like carbon (DLC) layer materials containing up to 40 atomic%, preferably 5 to 25 atomic% and especially 5 to 20 atomic% of a metal selected from Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Ni and W, with tungsten being preferred. Likewise, the term "Si-DLC" refers to diamond-like carbon (DLC) laminates containing up to 30 atomic%, preferably 5 to 25 atomic% and most preferably 5 to 20 atomic% silicon.

Preferably, the Si-DLC and Me-DLC materials deposited according to the invention are X-ray amorphous, ie that X-ray diffraction spectra of the cover layer have no intensity maxima at the Bragg angles characteristic of silicon carbide and Me carbides. Nevertheless, the X-ray amorphous cladding layers may occasionally have embedded SiC and / or MeC crystallites of smaller equivalent diameter 10 nm, where the term "equivalent diameter" refers to a sphere of the same volume as the nanocrystallite. If present, such singulated nanocrystallites are visible in images taken by transmission electron microscopy (TEM) of fractured or cut edges of the cover layers. In addition to X-ray amorphous cover layers, covering layers are also provided within the scope of the invention which contain a fraction of embedded Me carbide crystallites with an equivalent diameter of less than 10 nm, which is clearly visible in X-ray diffraction spectra and TEM images.

The cover layers according to the invention preferably exhibit a glass-like morphology in electron-microscopic SEM or TEM images. In particular, the cover layers according to the invention are free of column structures of any kind.

The combination of the three material components Si-DLC, DLC and Me-DLC in the topcoat in the manner described above, i. in a nearly homogeneous distribution constitutes an essential aspect of the present invention. It enables the deposition of cover layers with a property profile adapted to the mechanical specification and the operating conditions of the respective component. The combination of the three material components Si-DLC, DLC and Me-DLC creates additional possibilities and degrees of freedom for modifying and adapting the properties of coated components.

The properties of typical single layer coatings of Si-DLC, DLC and Me-DLC known in the art are shown in the following table.

Si-DLC DLC Me-DLC

Hardness HU _p i _ast 23 to 30 GPa 20 to 40 GPa 15 to 20 GPa

Coefficient of friction μ 0.05 to 0.15 0.15 to 0.2 0.1 to 0.3

1.2 x 10 ^"15 to 0.5 x 10 ^{" 1S} to 2 x 10 ^"15 to

wear coefficient

4.0 x 10 ^"15 m ³ / (Nm) 1.0 x ^10'15 m ³ / (Nm) 10 x 10 ^{" 15} m ³ / (Nm)

Surface energy 30 to 35 mN / m 35 to 40 mN / m 40 to 50 mN / m

Temperature resistance up to -500 ° C to -350 ° C to -350 ° C

Toughness low low high

Liability medium medium good tends to increase

Morphology vitreous vitreous

pillaring

Surprisingly, overcoats according to the invention have properties which can not be explained by a weighted average of the properties of the individual components Si-DLC, DLC and Me-DLC. Rather, the respective advantageous properties of the Si-DLC, the DLC or the Me-DLC component appear to compensate for the weaknesses of the other components. With the HUpiast hardness, in some cases even values are measured which exceed the hardness achievable with DLC.

In addition to a hardness HUpiast of up to 50 GPa and a low coefficient of friction μ of 0.05 to 0.20, the coating according to the invention is characterized by a high temperature resistance. In contrast to layers of DLC and Me-DLC, which degrade already from 350 ° C, keep the outer layers of the present invention in normal operation temperatures of up to 500 ° C.

The invention has the further object to provide a method for producing workpieces with a coating system of the type described above.

This object is achieved by a method for PVD coating of workpieces, comprising one or more steps St to S _N , where N = 1, 2, 3, wherein in step S _N a Si-DLC, DLC, Me-DLC and hydrogen containing overcoat layer, wherein Me is selected from the group comprising Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Ni, W, by means of one or more simultaneously operated magnetron cathodes are deposited with the same or different targets, wherein one or more targets 20 to 100 atomic% silicon, one or more targets 20 to 100 atomic% carbon, one or more targets 20 to 100 atomic% Me and the deposition is carried out in an atmosphere having a nominal hydrogen content of less than 30 atomic%.

Further embodiments of the method according to the invention are characterized in that:

- One or more targets of silicon, carbon, preferably in the form of graphite and optionally additives, one or more targets of graphite and optionally additives, and one or more targets of Me, in particular tungsten, carbon, preferably in the form of graphite and optionally additives consist;

- One or more targets of graphite, embedded in the graphite moldings of silicon or silicon carbide and optionally additives, wherein the embedded moldings are preferably arranged uniformly in the region of the target erosion;

- One or more targets of graphite, embedded in the graphite moldings of Me or Me carbide and optionally additives, wherein the embedded moldings are preferably arranged uniformly in the region of the target erosion; one or more targets made of graphite, embedded in the graphite Foimkörpern of silicon or silicon carbide embedded in the graphite moldings of Me or Me carbide and optionally additives, wherein the embedded moldings are preferably arranged uniformly in the range of target erosion;

one or more targets of materials selected from SiC, a mixture of Si and SiC, a mixture of graphite and SiC, a mixture of graphite and Si, a mixture of graphite and Si and SiC, W, WC, Ti, TiC, V, VC, Cr, CrC, Zr, ZrC, Nb, bC, Mo, Mo ₂ C, Hf, HfC, Ta, TaC, Ni or nicx and optionally additives exist;

one or more targets of materials selected from Me carbide, a mixture of Me and Me carbide, a mixture of graphite and Me carbide, a mixture of graphite and Me, a mixture of graphite and Me and Me carbide and optionally additives consist; the method comprises one or more steps Si to SN-I, where N = 2, 3,..., wherein by magnetron sputtering one or more targets of materials selected from graphite, W, WC, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Si, Ni and SiC or a mixture of these materials in an inert or reactive, optionally hydrogen-containing plasma, an adhesive layer and / or one or more intermediary layers or layer systems are deposited;

in one or more of steps S] to S, targets or gases containing a dopant such as boron or sulfur are used;

- uses unbalanced magnetron cathodes and / or to the workpieces to be coated, a bias potential of up to -300 V, preferably from -50 to -200 V, and in particular from -100 to -200 V is applied; and or

- Before performing steps S 1 to SN, the surface of the workpieces is pretreated by means of ion etching, in particular using Ar ions.

According to the invention, the deposition of the outer layer and the optional mediator layers takes place in an atmosphere comprising an inert gas consisting of argon, neon, helium, xenon, krypton or a mixture thereof and optionally one or more reactive gases, such as acetylene (C ₂ H ₂ ). , Methane (CH ₄ ), nitrogen (N ₂ ), silanes (Si _m H _n ), in particular monosilane (S1H ₄ ), organosilanes, in particular tetramethylsilane (C ₄ Hi ₂ Si) and hexamethyldisiloxane (C ₆ H ₁₈ OSi ₂ ) and Organosilazane.

The atmosphere or the plasma in which the deposition of the top layer of Si-DLC takes place, has a hydrogen content of nominally less than 30 atomic%. In the context of the invention, the nominal content of the hydrogen content refers to completely dissociated gas molecules. For example, when a mixture of 80% by volume of argon (Ar) and 20% by volume of acetylene (C ₂ H ₂ ) is used as the atmosphere for the deposition, the nominal hydrogen content is calculated according to the following equation (I):

(I) 20 × 2H / (80 × 1 Ar + 20 × 2 C + 20 × 2 H) = 40 H / 160 (Ar + C + H) = 25 atomic%

According to equation (I), all gas molecules or atoms are considered to be completely dissociated. During deposition or during sputtering the atmosphere is continuously supplied with fresh gas. The amount of the various gases or the gas flow fed in per unit time is set by means of regulators referred to as Massflow Controllers (MFC), which can be programmed in memory by a programmable controller (PLC) or a computer programmatically. The gas flow is usually specified in the unit "standard cubic centimeter per minute" (sccm). During the deposition of the Si-DLC cap layer, the amount of gas introduced per minute is controlled so that, in the resulting gas mixture, the nominal hydrogen content calculated in accordance with equation (I) is less than or equal to 30 atomic%. The actual stoichiometric composition of the atmosphere or plasma in which the deposition occurs differs due to various effects, such as the gas species dependent pumping power of turbomolecular pumps, the gas-type dependent conductivities of the vacuum piping and valves between pump (s) and recipient and the storage the gas atoms in the deposited layer from the nominal value calculated according to equation (I). The nominal value can be precisely controlled by means of MFC and is therefore used to describe the method according to the invention.

Due to the proportion of at least 2.5 atomic% of a metal Me, the cover layers according to the invention are electrically conductive to a limited extent, whereby the dissipation of surface charges during magnetron sputtering is favored and spontaneous arc discharges are effectively avoided.

The invention is explained in more detail below with reference to figures, wherein

Fig. 1-5 coated workpieces;

Fig. 6a, 6b devices for PVD coating; and

Fig. 7 shows a target of a magnetron cathode.

FIG. 1 shows a cross-section of a workpiece 10 according to the invention with a base body 1 and a cover layer 6 containing Si-DLC, DLC and Me-DLC, which has a hydrogen content of 2.5 to 20 atomic%, preferably 5 to 18 atomic%, in particular 5 to 15 atomic%, and more preferably 5 to 10 atomic%. The directional arrow provided with the reference numeral 16 symbolizes the surface normal of the main body 1 and the cover layer 6. The cover layer 6 contains 2.5 to 30 atomic% silicon and 2.5 to 30 atomic% of a metallic element Me selected from the group comprising Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Ni, W, each in a substantially homogeneous Distribution. In the context of the present invention, the term "essentially homogeneous distribution" designates the fact that the deposition of the cover layer 6 takes place under controlled conditions in such a way that any partial volume 6A of the cover layer 6 having a size of 40 × 40, shown in FIG x 40 nm to 200 x 200 x 200 nm ^{3 has} a silicon content and a Me content of 2.5 to 30 atom%.

In the context of the invention, cover layers 6 are also provided, in which each partial volume 6A having a size of 40 × 40 × 40 nm ³ to 60 × 60 × 60 nm ³ , 80 × 80 × 80 nm ³ to 100 × 100 × 100 nm ³ , 100 x 100 x 100 nm ³ to 120 x 120 x 120 nm ³ , 120 x 120 x 120 nm ³ to 140 x 140 x 140 nm ³ , 140 x 140 x 140 nm ³ to 160 x 160 x 160 nm ³ , 160 x 160 x 160 nm ³ to 180 x 180 x 180 nm ³ , and / or 180 x 180 x 180 nm ³ to 200 x 200 x 200 nm ³ a silicon content and a Me content of 2.5 to 30 atom -% having. The dimensions (x nm) x (y nm) x (z nm) for the volume 6A preferably refer to a Cartesian coordinate system whose third axis z is arranged parallel to the surface normal 16. As explained below, the cover layer 6 is designed in the manner of a multilayer or multiple layer or as a more or less homogeneous, optionally in the direction of the surface normal 16 graded layer. All embodiments of the cover layer 6 according to the invention are characterized in that an arbitrary partial volume of the cover layer 6, which in the direction of the surface normal 16 has a thickness of greater than or equal to 40 nm, a silicon content and a Me content of 2.5 to 30 atomic%. For example, a partial volume 6A with a size of 1000 × 1000 × 40 nm has a silicon content and a Me content of 2.5 to 30 atom% in each case. Accordingly, the core of the invention is an essentially Si-DLC, DLC and Me-DLC covering layer 6 having a quasi-homogeneous or quasi-isotropic chemical composition. The term "quasi-homogeneous" or "quasi-isotropic" refers to the fact that anisotropies of the chemical composition can only be detected if a stoichiometric measuring method, such as, for example, selective ion mass spectrometry (SIMS) with a spatial resolution of less than 40 nm in direction the surface normal 16 is used.

The cover layer 6 is deposited primarily by two methods (A) or (B) or a combination of the methods (A) and (B). A covering layer 6 produced according to the method (A) is shown in FIG. 3 and comprises one or more triple layers 66, each one of them first layer 6A, a second layer 6B and a third layer 6C. The thicknesses of the layers 6A, 6B and 6C are in each case 0.1 to 20 nm, preferably 1 to 10 nm and in particular 1 to 5 nm. The layers 6A, 6B and 6C are in the direction of the surface normal 16 in an arbitrarily defined order 6A / 6B / 6C, 6A / 6C / 6B, 6B / 6C / 6A, 6B / 6A / 6C, 6C / 6A / 6B or 6C / 6B / 6A. According to the method (A), each of the layers 6A, 6B, 6C is deposited by means of a separate magnetron cathode with a target having a defined stoichiometry. For the purpose of depositing the cover layer 6, a plasma zone is formed in front of each of the magnetron cathodes, the composition of which corresponds essentially to the stoichiometry of the respective target. The chemical composition of the plasma zone is primarily determined by the stoichiometry of the target, whereby known and publicly tabulated influencing factors, such as the element-specific sputtering rates, have to be taken into account (see, for example, ht ^ // www.npl.co.iik / science-teclmology / SOT

values). During the deposition of the cover layer 6, the workpieces to be coated, also referred to below as substrates, are rotated about one or more axes by means of a known substrate holder with planetary gear and guided at predetermined angular frequency through the plasma zone of each of the magnetron cathodes. The method (A) corresponds to the known in the prior art sputtering method for the deposition of multilayer and superlattice coatings. By appropriately setting the electric power supplied to each magnetron cathode and, associated therewith, the sputtering rate and the rotational speed of the substrate holder or the residence time of the substrates in the plasma zones of the magnetron cathodes, the thickness and stoichiometry of the layers 6A, 6B, 6C can be adjusted in a targeted manner. In order to adjust the process parameters, the thickness and chemical composition of the layers 6A, 6B, 6C and the cover layer 6 produced by the method (A) are determined by means of known measuring methods such as electron micrographs of sections in a scanning electron microscope and / or a transmission electron microscope, by means of electron Sample Micro Analysis (or EDX or ESCA) and / or Secondary Ion Mass Spectrometry (SIMS) in conjunction with Elastic Recoil Detection (ERD). This procedure is common in the art and allows the process parameters to be determined in one to two runs on one to two test batches of a few coated substrates.

In the method (B), the cover layer 6 is deposited by means of one or more magnetron cathode with the same target, wherein the target or targets a composition have, which corresponds to the predetermined for the cover layer 6 stoichiometry. With regard to the chemical composition of the targets, known and publicly tabulated influencing factors, such as the element-specific sputtering rates, must be taken into account (see, for example, http://www.npl.co.uk/science-technology/surface-and-nano-malysis/services / spu

values). As in the method (A), the method parameters for method (B) are adjusted by means of measurements of the chemical composition of the cover layer 6 by means of SIMS in conjunction with ERD and EDX / ESCA. The cover layers 6 produced in accordance with method (B) preferably have a homogeneous composition in the direction of the surface normal 16 such that each partial volume having a size of 10 × 10 × 10 nm or less has an Si content of 2.5 to 30 atomic weight. % and has a Me content of 2.5 to 30 atomic%.

The hydrogen content of the cover layer 6 is determined above all by the hydrogen content of the plasma zones in front of the magnetron cathodes. If the deposition takes place in an industrial coating plant with a typical power density at the target surface of about 5 to 15 W-cm ^" in a gas atmosphere with a low hydrogen content, eg argon to acetylene (C ₂ H ₂ ) in a ratio of 350 sccm to 25 sccm, so the hydrogen content in the cover layer 6 is in the range of 5 to 6 atom% By increasing the proportion of acetylene or methane (CH ₄ ), the hydrogen content in the cover layer 6 can be raised to values of up to 20 atom%. In order to adjust the silicon and Me content of the cover layer, for example, one or more magnetron cathodes with targets of silicon (Si), silicon carbide (SiC), graphite (C), a metal (Me) selected from the group comprising Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Ni, W and / or Me carbide used.

Depending on the choice of the target materials and the sputtering gas, the silicon, Me and hydrogen content of the cover layer 6 within the above-mentioned limits of 5 to 20 atomic% hydrogen, 2.5 to 30 atom% of silicon and 2.5 to 30 atom% Me set. Optionally, the targets of the magnetron cathodes include additives such as boron, aluminum, tungsten, vanadium and / or sulfur, which reduce the coefficient of friction μ of the cover layer 6 and / or increase the electrical conductivity of target materials without a metallic component. The additives contained in the targets are deposited in the cover layer 6 during sputtering. Preferably, the cover layer 6 has a content of boron and / or sulfur of 0.01 to 6.0 atom%.

The cover layer 6 is 0.4 to 5.0 μιη, preferably 0.6 to 3.0 μπι, and in particular 0.8 to 2.0 μηι thick. The thickness of the cover layer 6 is determined by the product of deposition rate and Separation duration or determined at a variable deposition rate by the time integral of the deposition rate. The deposition rate in turn is a function of several variables, such as number, target size and target material of the magnetron cathodes, sputtering current and the gas mixture used and the geometric arrangement of the parts to be coated and their movement or multiple rotation, etc. By appropriate adjustment of the deposition rate and the deposition time, the thickness the cover layer 6 is set.

If three or more different magnetron cathodes or target materials are used for the deposition of the cover layer 6, for example lxSiC + lxGraphit + l tungsten, zones are formed in the PVD coating device in front of the respective magnetron cathodes whose content of carbon, silicon and Tungsten atoms differ from each other. Thus, in front of a magnetron cathode with a graphite or tungsten target, a plasma zone is formed which is substantially free of silicon. In contrast, a zone in front of a magnetron cathode with SiC target contains both silicon and carbon. Alternatively, one or more SiC or Si targets and tungsten carbide or tungsten targets are combined with a carbonaceous sputtering gas such as a mixture of argon and acetylene (C ₂ H ₂ ) in a volume ratio of 350:40, ie nominal Hydrogen content of 40x2 / (350x1 + 40x2 + 40x2) = 80/510 = 15.7 atom% used. The coating zone in front of an Si target or a tungsten target then contains both silicon and carbon or both tungsten and carbon, so that a workpiece 1 located in the respective coating zone has a Si-DLC layer or a Me-DLC layer is deposited. As already explained above, a volume ratio of argon to acetylene in the sputtering atmosphere of, for example, 350:40 is set by controlling the gas flows introduced via the MFC to 350 sccm of argon and 40 sccm of acetylene.

In a preferred embodiment of the invention, the workpieces to be coated are moved through the coating zones during the coating process by means of a planetary drive inside the PVD inspection device and preferably by means of magnetron cathodes, which generate a tunnel-like magnetic field and a large-volume plasma in conjunction with electromagnetic field coils, using a negative Substrate potential caused ion bombardment coated. The workpieces to be coated are mounted on substrate holders. The substrate holders are mounted on a turntable and rotatable about its longitudinal axis. During the deposition of the cover layer 6 the turntable and the substrate holder are rotated with the workpieces by means of the planetary drive, wherein the time-dependent path s (t) of a workpiece in a horizontal plane defined by coordinates (u, v) is described by the following formula: s (t) = (u ( t); v (t)) = (R _D -cos ((oD-t) + Rs-cos (β) st + Δφ); R _D -sin (ro _D -t) + Rs-sin ((ö _S -t + Δφ)) with t Ξ time; RD = turntable radius; Rs ^Ξ substrate ^holder radius;

ωο ^Ξ turntable angular velocity; cos = substrate holder angular velocity; and Δφ angle offset between substrate holder and turntable

Preferably, the ratio of the angular velocities COS AOD is a fractionally rational, in particular irrational number, so that the path s (t) is not stationary.

Upon complete rotation of the turntable, each workpiece is once passed through the coating zone in front of each of the magnetron cathodes. Depending on the silicon carbon and Me content of the various coating zones, a thin layer of Si-DLC, DLC or Me-DLC is deposited on the workpiece. Consequently, the cover layer 6, as shown in Fig. 3, 4, 5, a fine structure of triple layers 66 with individual layers 6A, 6B, 6C. The thickness of the alternating layers 6A, 6B, 6C is in each case independently in the range from 0.1 to 20 nm, preferably 1 to 10 nm and in particular 1 to 5 nm.

In a particularly preferred development of the invention, the silicon content of the cover layer 6 is varied by increasing or decreasing the ratio of the electrical powers and thus the deposition rates of the magnetron cathodes with silicon-containing target relative to the magnetron cathodes with graphite and Me target. Alternatively or additionally, the composition of the sputtering gas, for example the volume ratio (sccm) of acetylene to argon is varied. In particular, the coating process is performed so that the silicon content of the cover layer 6 in the direction of a surface normal 16 of the main body 1 or the cover layer 6, i. increases with increasing distance from the base body 1.

Advantageous developments of the invention are shown in Figures 3, 4 and 5. Accordingly, an adhesive layer 2 and / or a first and second mediator layer 3, 4 or a first and second layer system 30, 40 and / or a third mediator layer 5 are arranged between the base body 1 and the cover layer 6. The adhesive layer 2 directly adjoins the main body 1 and optionally the cover layer 6. The first 3 000956

23

Mediator layer 3 or the first layer system 30 directly adjoins the base body 1 or the adhesion layer 2 and possibly the cover layer 6. The second mediator layer 4 or the second layer system 40 directly adjoins the base body 1, the adhesion layer 2, the first mediator layer The third mediator layer 5 directly adjoins the cover layer 6 as well as the base body 1, the adhesion layer 2, the first mediator layer 3, the first layer system 30, the second mediator layer 4 or the like second layer system 40.

Starting with the base body 1, the respective layers or layer systems in the direction of a surface normal 16 of the base body are identified in ascending order by the reference symbols 2, 3 or 30, 4 or 40, 5 and 6. The embodiments shown in FIGS. 3, 4 and 5 merely represent a subset of the 36 possible combinations of the layers or layer systems 2, 3, 30, 4, 40, and 5 between the base body 1 and the cover layer 6. The number 36 of the possible combinations results from the following consideration:

Layer or layer system possibilities number

Adhesive layer no | Yes 2

first intermediary layer / first layer system no \ 3 \ 30 3

second mediator layer / second layer system no | 4 | 40 3

third intermediary layer no | Yes 2

Total possibilities: 2 x 3 x 3 x 2 = 36

As shown in FIG. 4, the first layer system 30 consists of one or more bilayers n x (31, 32), where n is an integer greater than or equal to 1. The second layer system 40 comprises one or two layers 41 or 41, 42.

The thickness of the layers 3, 31, 32, 4, 41, 42, 5 is in each case 0.1 to 3.0 μπι, preferably 0.1 to 0.8 μιη, and in particular 0.1 to 0.6 μι ^η .

The adhesive layer 2, the intermediary layers 3, 30, 4, 40 and 5, respectively, improve the adhesive strength of the cover layer 6 and / or reduce the thermal mismatch, i. the difference between the coefficients of thermal expansion of the cover layer 6 and the base body. 1

If the base body I consists of a soft material, then the adhesive layer 2, the intermediary layers or layer systems 3, 30, 4, 40 and / or 5 have the additional function of providing a supporting support with increased strength for the cover layer 6. In the context of the invention, in particular the deposition of an adhesive layer 2 of Ti, V, Cr, CrN, Zr, Nb, Mo, Hf, Ta, Si or Ni on the base body 1 is provided. For this purpose, a magnetron cathode with a target of Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Si or Ni is used. An adhesion layer 2 made of CrN is deposited in a nitrogen-containing gas atmosphere, for example a mixture of argon and nitrogen (N ₂ ), ie by means of reactive magnetron sputtering.

To compensate for the thermal mismatch, a first mediator layer 3 or one or more double layers (31, 32), a second mediator layer 4, 41 or (41, 42) and / or a third mediator layer 5 of SiC _x , WC _X are expediently used. Si-DLC, Me-DLC, in particular W-DLC or DLC directly on the base body 1 or a previously produced adhesive layer 2 of Ti, V, Cr, CrN, Zr, Nb, Mo, Hf, Ta, Si or Ni deposited, wherein 0, 1 <X <2.0.

The thickness of the alternating layers 31 and 32 is in each case 0.1 to 3.0 μχη, preferably 0.1 to 1, 5 μιη and in particular 0.1 to 0.6 μηι. The bilayers (31, 32) are sequentially deposited by sputtering alternately with selected magnetron cathodes while the remaining magnetron cathodes are turned off or operated at a low electrical power below the value required for sputter deposition. As an alternative to a reduction in the electrical power of the magnetron cathodes, the use of shielding screens is provided, which are moved automatically or by means of electronic control and release or cover the target of the respective magnetron cathode. Such shielding screens commonly used in the art allow the magnetron cathodes to be operated at substantially constant power and to stabilize the sputtering parameters.

For example, an Si-DLC layer is first produced by means of one or more magnetron cathodes with an SiC target. Following this, the magnetron cathode with SiC target is switched off or switched off and one or more magnetron cathodes with WC target are switched on in order to deposit a W-DLC layer. If necessary, the above sputtering steps are repeated several times in order to produce a layer system 30 with a plurality of double layers (31, 32). In an analogous manner, by alternately using magnetron cathodes with Si, SiC, W, WC, graphite, MeC or Me target, one or more double layers (31, 32) of the types (SiC _x / MeC _x ), (MeC _x, SiC _x), (SiC _x / DLC), silicon carbide (SiC _x / Me-DLC), (MeC _x / Si-DLC), (Si-DLC / MeC _x), (W-DLC / SiC _x) , (Si-DLC / DLC), (Si-DLC / Me-DLC), (DLC / Si-DLC) or (Me-DLC / Si-DLC) deposited, with Me-DLC preferably as W-DLC and MeC _x preferably designed as a WC _x . In contrast, layers of Si-DLC, DLC and Me-DLC, in particular W-DLC with a thickness of 0.1 to 20 nm, are deposited simultaneously in different coating zones in front of the respective magnetron cathodes during the deposition of the cover layer 6.

FIGS. 6a and 6b show schematic plan views of PVD coating devices 100, 100 'for producing the coating systems according to the invention. The PVD coating devices 100, 100 'comprise a vacuum chamber 110, in which one or more magnetron cathodes (50, 50, 60, 60, 70, 70), respectively (50, 60, 70, 120, 130, 140) with targets ( 51, 51; 61, 61; 71, 71), respectively (51, 61, 71, 121, 131, 141) are arranged. The magnetron cathodes (50, 50; 60, 60, 70, 70) and (50, 60, 70, 120, 130, 140) are designed as unbalanced magnetron cathodes which are used in conjunction with electromagnetic field coils, the tunnel-like magnetic fields on the magnetron cathodes and generate a far field, which encloses a large part of the parts to be coated and initiates electrons present in front of the magnetrontargets in the coating chamber. As a result, a large-volume dense plasma is generated in a large area around the parts to be coated. A negative bias potential of 200 V is applied to the parts to be coated, causing intense ion bombardment of the parts during coating. This ion bombardment is necessary for the deposition of high-quality hard material and DLC layers of all executions. The workpieces 1 to be coated are fastened to substrate holders 90, which are mounted rotatably about their longitudinal axis on a turntable (not shown in FIGS. 6a and 6b). By means of a planetary drive (not shown), the turntable and simultaneously the substrate holder 90 with the workpieces 1 are rotated. The rotation of the turntable and the substrate holder 90 is indicated by circular arrows 91 and 92, respectively.

The deposition of the coating systems of the invention takes place in a controlled atmosphere 80 at a pressure of 0.5x10 ^"to 0.05 mbar. In order to maintain the low pressure PVD coating apparatus 100 is connected to a pump stand, in particular turbo-molecular pump (not shown). About one or more feeds 150 are continuously inert gases in the PVD coating device 100, such as argon, krypton or xenon and optionally reactive gases such as acetylene (C ₂ H ₂ ), methane (CH ₄ ), nitrogen (N ₂ ), silanes ( Si _m H _n ), in particular monosilane (S1H ₄ ), organosilanes, in particular tetramethylsilane (C ₄ Hi ₂ Si) and hexamethyldisiloxane

and organosilazanes and possibly mixtures of inert gases and reactive gases passed in order to influence the composition of the atmosphere or the plasma 80 and the deposited on the workpieces 1 layers in a targeted manner. To control the volume flow of the various gases, the feeders 150 are equipped with electrically adjustable valves or mass flow controllers (abbreviated to MFC).

Each of the magnetron cathodes (50, 50, 60, 60, 70, 70) and (50, 60, 70, 120, 130, 140) is connected to a separately controllable electrical power supply (not shown). The magnetron cathodes are preferably operated with DC voltage or pulsed DC voltage (so-called DC magnetron sputtering).

In addition, a DC voltage source (not shown) for applying a bias voltage of up to -300 V, preferably -50 to -200 V or an etching voltage of up to -2000 V, preferably -1000 V, to the workpieces 1 to be coated is provided. In this case, in a further preferred embodiment, a pulsed direct voltage or DC voltage source is connected to the substrates. Accordingly, the turntable and the substrate holder 90 are made of an electrically conductive material, such as steel and electrically connected to the DC voltage source for the bias voltage.

The bias voltage or the bias potential accelerate ionized gas atoms, for example Ar ions from the plasma 80, to the workpieces to be coated. Due to the ions impinging on the surface of the workpieces, kinetic energy is transferred to the surface atoms (so-called ion bombardment). In particular, in the deposition of Me-DLC, DLC and Si-DLC layers by ion bombardment with a bias potential between -50 and -300 V, the layer properties, such as hardness, wear resistance and layer structure and the proportion of sp ³ bonded carbon are optimized ,

In a further development of the invention, the surface of the workpieces 1 is cleaned prior to deposition of the adhesive layer 2, the mediator layers 3, 4 and optionally 5 or layer systems 30 and 40 or before deposition of the cover layer 6 by means of ion etching, preferably with argon ions. For this purpose, a voltage of up to -1000 V is applied to the substrate holder 90 or to the workpieces 1.

Fig. 7 shows a plan view of a target (51, 71) comprising a first carrier 200 preferably formed as a cuboidal or oval plate and embedded in the carrier Shaped body 220 includes. The carrier 200 is preferably made of graphite or graphite and up to 15 wt .-% additives, such as binders. The shaped bodies 220 are preferably of cylindrical or cuboid shape and consist of materials which contain silicon and / or a metal selected from the group comprising Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Ni, W, where tungsten is preferred. In expedient embodiments of the method according to the invention, the shaped bodies 220 consist of materials such as silicon, silicon carbide, mixtures of silicon and graphite, tungsten, tungsten carbide, mixtures of tungsten and graphite and / or mixtures of the above materials. The shaped bodies 220 are preferably arranged in a region 210 of maximum sputter erosion of the target (51, 71) designated in professional circles as a racetrack.

The properties of the workpieces (10, 11, 11 ', 12, 13) according to the invention and of the cover layers 6 are determined using the following measuring methods:

- hardness HUpiast according to ISO EN 14577 with Fischerscope® H100C from Helmut Fischer GmbH, Sindelfingen (DE) with Vickers diamond tip and a test load of 20 to 50 mN;

Coefficient of friction μ by pin-on-disk test according to DIN EN 50324 (ASTM G99) with a tribometer of CSM Instruments SA, Peseux (CH) in air with a relative humidity of about 50% (~ 9 g / m) ³ water vapor content);

- Wear resistance by Kalottenverschleißtest (commonly referred to as Ball Crater or Calo test) according to ISO EN 1071-6 with the instrument kaloMAX NT BAQ GmbH, Braunschweig (DE) with a suspension of A1 ₂ 0 ₃ powder with a Grain size of 1 μηι in glycerol as an abrasive paste, a steel ball with 30 mm diameter, a contact pressure of 0.54 N, and a number of revolutions of 50 to 55 U / min with a grinding time of 3 to 9 minutes, a grinding path of 17 to 51 m and a grinding depth of 0.4 to 1.2 μιη;

- Bonding strength by means of Rockwell A test on carbide substrates and otherwise by means of Rockwell C test in accordance with VDI 3198 guideline at a pressure of 588.4 N or 1471 N;

Adhesive strength or critical load value Lc ₂ by means of scratch test in accordance with ISO EN 1071-3 with a CSM Scratch Tester Micro from CSM Instruments SA, Peseux (CH);

Silicon and carbon content by electron probe micro-analysis (or EDX or ESCA) using an energy-dispersive Si (Li) detector; Elemental composition and hydrogen content by secondary ion mass spectrometry (SIMS) with cesium ions according to the method of Willich et al. (Willich, M. Wang, K. Wittmack, Quantitative Analysis of WC.H Coatings by EPMA, RBS (ERD) and SIMS, Microchim., Acta 114/115, 525-532 (1994), P. Willich, C.). Steinberg, SIMS depth profile of wear resistant coatings on cutting tools and technical components, Applied Surface Science 179 (2001) 263-268). The mass spectrometer of the SIMS instrument was calibrated on the basis of the results of Elastic Recoil Detection (ERD) of three reference samples. As comparative samples steel plates were used with a first 0.5 μπι thick coating of tungsten and a second 3 μηι thick coating of Si-DLC with a hydrogen content of about 5, 10 and 15 atom%. The ERD measurements were carried out at Forschungszentrum Dresden-Rossendorf using a ⁴ He ²⁺ primary beam with an energy of 2.4 MeV; and

Contact angle and surface energy by wetting the cover layer with water according to DIN 55660-2 (2011-12 edition) and DIN 55660-5 (2012-04 edition) or ASTM D7334-08 with a DSA 10 type instrument from Krüss GmbH.

Claims

claims

A workpiece (10, 11, 12, 13) comprising a base body (1) and a cover layer (6) containing Si-DLC, DLC, one or more types of Me-DLC and 2.5 to 20 atomic% hydrogen in which Me is selected from the group comprising Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Ni, W, and the covering layer has a hardness of 15 to 50 GPa, characterized in that the covering layer (6) consists of partial volumes (6A) of size 40 x 40 x 40 nm ³ to 200 x 200 x 200 nm ³ and each sub-volume (6A) has an average Si content of 2.5 to 30 atomic% and an average Me content of 2.5 to 30 atomic%.

Second workpiece (10, 11, 12, 13) according to claim 1, characterized in that each partial volume (6A) has an Si content of 5 to 25 atomic%, preferably 8 to 20 atomic% and a Me content of 5 to 25 atomic%, preferably 10 to 20 atomic% ».

3. workpiece (10, 11, 12, 13) according to claim 1 or 2, characterized in that the cover layer (6) has a hydrogen content of 5 to 18 atomic%, preferably 5 to 15 atomic%, and in particular 5 to 10 atom%.

4. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 3, characterized in that the cover layer (6) has a thickness of 0.4 to 5.0 μηι, preferably 0.6 to 3, 0 μπι, and in particular 0.8 to 2.0 μιη has.

5. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 4, characterized in that the cover layer (6) has a hardness HU _p iast of 20 to 40 GPa and preferably 25 to 40 GPa.

6. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 5, characterized in that the cover layer (6) has a coefficient of friction μ of 0.05 to 0.20, preferably 0.05 to 0, 15, and in particular 0.05 to 0.1.

7. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 6, characterized in that the cover layer (6) according to Kalotest with a suspension of Al2O3 powder in glycerol a coefficient of wear of 0.5 x 10th ^{~ 15} to 4.0x 10 ^"15 m ³ / (Nm), preferably 0.5 x 10 ^"15 to 2.5 x 10 ^{" 15} m ³ / (Nm), and in particular 0.5 x 10 ^"15 to

I, 5 x 10 ^"15 m ³ / (-m).

8. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 7, characterized in that the cover layer (6) by means of a Rockwell A test for basic body (1) of hard metal and otherwise measured by Rockwell C test Adhesive strength HF1 to HF4, preferably HF1 to HF3, and in particular HF1 to HF2.

9. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 8, characterized in that the cover layer (6) has a content of 0.01 to 6.0 atom% of an additive selected from boron, Sulfur and mixtures thereof.

10. workpiece (10,

11, 12, 13) according to one or more of claims 1 to 9, characterized in that Me is tungsten.

II. Workpiece (11, 12, 13) according to one or more of claims 1 to 10, characterized in that the cover layer (6) comprises one or more triple layers (66) and each of the triple layers (66) of a layer Si-DLC (6A), a layer DLC (6B), and a layer Me-DLC (6C), and the layers (6A), (6B), and (6C) are arranged in an arbitrary fixed periodic order.

12. workpiece (11, 12, 13) according to claim 11, characterized in that the layers (6A), (6B) and (6C) independently of one another in each case a thickness of 0.1 to 20 nm, preferably 1 to 10 nm, and in particular 1 to 5 nm.

13. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 12, characterized in that the silicon content in the cover layer (6) with increasing distance from the base body (1) increases.

14. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 13, characterized in that the workpiece (10, 11, 12, 13) one between the cover layer (6) and the base body (1) arranged and to the base body (1) adjacent adhesive layer (2) of Ti, V, Cr, CrN, Zr, Nb, Mo, Hf, Ta, Si or Ni or a mixture of these materials.

15. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 14, characterized in that the workpiece (10, 11, 12, 13) one between the cover layer (6) and the base body (1) or the adhesive layer (2) arranged and to the base body (1) or the adhesive layer (2) adjacent first mediator layer (3) of SiCx, MeCx or WCx and optionally one between the first mediator layer (3) and the cover layer (6) arranged and first mediator layer (3) comprises adjacent second mediator layer (4) of DLC, Si-DLC or Me-DLC, in particular of W-DLC, and in the mediator layers (3, 4) the following material pairings are present:

wherein Me-DLC is preferably designed as W-DLC.

16. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 14, characterized in that the workpiece (10, 11, 12, 13) between the cover layer (6) and the base body (1) or the adhesive layer (2) arranged and to the base body (1) or the adhesive layer (2) adjacent first layer system (30) of one or more double layers (31, 32) of (SiC _x / WC _x ), (SiC _x / MeC _x ), (WC _x / SiC _x ) or (MeCx / SiCx) and optionally a second between the cover layer (6) and the first layer system (30) arranged and adjacent to the first layer system (30) Layer system (40), wherein the second layer system (40) one layer (40) or two layers (41, 42) selected from SiC _x , (SiC _x / DLC), (SiC _x / Si-DLC), (SiC _x / Me-DLC), in particular (SiC _x / W-DLC) or MeC _x , (MeC _x / DLC), (MeC _x / Si-DLC) or (MeC _x / Me-DLC), in particular (WC _X / W -DLC), wherein MeCx is preferably in the form of WC _X , and in the layer systems (30, 40) the following material pairings are present:

where n is an integer greater than or equal to 1 and Me-DLC is preferably carried out as W-DLC and MeCx preferably as WC _x .

17. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 14, characterized in that the workpiece (10, 11, 12, 13) between the cover layer (6) and the base body (1) or the adhesive layer (2) arranged and to Base body (1) or to the adhesive layer (2) adjacent first layer system (30) of one or more double layers (31,32) of (SiC _x / DLC), (SiC _x / Si-DLC), (SiC _x / Me-DLC ), in particular (SiC _x / W-DLC) or (MeC _x / DLC), (MeC _x / Si-DLC), (MeC _x / Me-DLC), in particular (MeC _x / W-DLC) and optionally an intermediate The second layer system (40), arranged between the cover layer (6) and the first layer system (30) and adjacent to the first layer system (30), wherein the second layer system (40) comprises two layers (41, 42) selected from (SiC _x / DLC) , (SiC _x / Si-DLC), (SiCx / Me-DLC), in particular (SiC / W-DLC) or (MeC _x / DLC), (MeC _x / Si-DLC), or (MeC _x / Me). DLC), in particular (MeC _x / W-DLC) and in the layer systems (30, 40) the following material pairings are present:

Layer system (30) Layer system (40)

nx (31/32) (41) (42)

nx (SiC _x / DLC) SiCx DLC

nx (SiC _x / DLC) SiC _x Si-DLC

nx (SiC _x / DLC) SiC _x Me-DLC

nx (SiC _x / Si-DLC) SiC _x DLC

nx _(x SiC / Si-DLC) SiC _x Si-DLC

nx _(x SiC / Si-DLC) SiC _x Me-DLC

nx (SiCx / Me-DLC) SiC _x DLC

nx (SiC _x / Me-DLC) SiCx Si-DLC

nx (SiC _x / Me-DLC) SiC _x Me-DLC

nx (SiC _x / DLC) MeC _x DLC

nx (SiC _x / DLC) MeC _x Si-DLC

nx (SiCx / DLC) MeC _x Me-DLC

nx _(x SiC / Si-DLC) MeC _x DLC

nx _(x SiC / Si-DLC) MeC _x Si-DLC

nx (SiCx / Si-DLC) MeC _x Me-DLC

nx (SiC _x / Me-DLC) MeC _x DLC

nx (SiC _x / Me-DLC) MeC _x Si-DLC

nx (SiC _x / Me-DLC) MeC _x Me-DLC nx (MeC _x / DLC) SiC _x DLC

n (MECX / DLC) SiC _x Si-DLC

n (MeCx / DLC) SiCx Me-DLC

n x (MeCx / Si-DLC) SiCx DLC

nx (MeC _x / Si-DLC) SiCx Si-DLC

nx (MeC _x / Si-DLC) SiC _x Me-DLC

nx (MeC _x / Me-DLC) SiCx DLC

nx (MeC _x / Me-DLC) SiC _x Si-DLC

nx (MeC _x / Me-DLC) SiCx Me-DLC

nx (MeCx / DLC) MeC _x DLC

nx (MeCx / DLC) MeCx Si-DLC

nx _(x MeC / DLC) MeC _x Me-DLC

nx (MeC _x / Si-DLC) MECX DLC

nx (MeC _x / Si-DLC) MeC _x Si-DLC

nx (MeC _x / Si-DLC) MeC _x Me-DLC

nx (MeC _x / Me-DLC) MECX DLC

nx (MeCx / Me-DLC) MeCx Si-DLC

nx (MeC _x / Me-DLC) MeC _x Me-DLC where n is an integer greater than or equal to 1 and Me-DLC is preferably designed as W-DLC and MeCx preferably as WCx.

18. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 14, characterized in that the workpiece (10,11,12,13) one between the cover layer (6) and the base body (1) or the adhesive layer (2) arranged and to the base body (1) or the adhesive layer (2) adjacent first layer system (30) of one or more double layers (31,32) selected from (Si-DLC / SiC _x ), (Si-DLC / MeC _x ), in particular (Si-DLC / WC _X ) or (Me-DLC / SiC _x ), in particular (W-DLC / SiC _x ), (Me-DLC / MeC _x ), in particular (W-DLC / WC _X ) or (DLC / SiC _x ), (DLC / MeC _x ), in particular (DLC / WCx) and optionally a second layer system arranged between the cover layer (6) and the first layer system (30) and adjacent to the first layer system (30) (40), wherein the second layer system (40) comprises two layers (41.42) selected from (SiC _x / DLC), (MeC _x / DLC), (SiC _x / Si-DLC), (MeC _x / Si-DLC), (SiC _x / Me-DLC), in particular ( SiC _x / W-DLC) or (MeC _x / Me-DLC), in particular (MeC _x / W-DLC) and in the layer systems (30, 40) the following material pairings are present:

Layer system (30) Layer system (40)

nx (31/32) (41) (42)

nx (Si-DLC / SiC _x) SiCx DLC

nx (Si-DLC / MeC _x) SiCx DLC

nx (Si-DLC / SiC _x) Me C _x DLC

nx (Si-DLC / MeC _x) Me C _x DLC

nx (Si-DLC / SiC _x) SiC _x Si-DLC

nx (Si-DLC / MeC _x) SiC _x Si-DLC

nx (Si-DLC / SiC _x) Me C _x Si-DLC

nx (Si-DLC / MeC _x) Me C _x Si-DLC

n (Si-DLC / SiCx) SiCx Me-DLC

nx (Si-DLC / MeC _x) Me-DLC SiCx

nx (Si-DLC / SiC _x) Me C _x Me-DLC

nx (Si-DLC / MeC _x) Me-DLC MECX

nx (Me-DLC / SiC _x) SiC _x DLC

nx (Me-DLC / MeC _x ) SiCx DLC

nx (Me-DLC / SiC _x) Me C _x DLC

nx (Me-DLC / MeC _x ) MeC _x DLC

nx (Me-DLC / SiC) _x Si-SiC DLC

nx (Me-DLC / MeC _x) SiC _x Si-DLC

nx (Me-DLC / SiC _x) Me C _x Si-DLC

nx (Me-DLC / MeC _x ) MeC _x Si-DLC

nx (Me-DLC / SiC _x) Me-DLC SiCx

nx (Me-DLC / MeC _x ) SiC _x Me-DLC

nx (Me-DLC / SiC _x) Me-DLC MECX

x (Me-DLC / MeC _x ) MeC _x Me-DLC nx (DLC / SiCx) SiCx DLC

nx (DLC / MeC _x ) SiC _x DLC

nx (DLC / SiC _x) Me C _x DLC

nx (DLC / MeC _x ) MeCx DLC

nx (DLC / SiC _x) Si-DLC SiCx

nx (DLC / MeC _x) Si-DLC SiCx

nx (DLC / SiC _x) Me C _x Si-DLC

nx (DLC / MeC _x) Si-DLC MECX

nx (DLC / SiC _x) SiC _x Me-DLC

nx (DLC / MeC _x) Me-DLC SiCx

n x (DLC / SiCx) MeCx Me-DLC

nx (DLC / MeC _x) Me-DLC MECX

where n is an integer greater than or equal to 1 and Me-DLC is preferably carried out as W-DLC and MeCx preferably as WCx.

19. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 14, characterized in that the workpiece (10, 11, 12, 13) between the cover layer (6) and the base body (1) or the adhesive layer (2) and to the base body (1) or to the adhesive layer (2) adjacent layer system (30) of one or more double layers (31, 32) of (Si-DLC / DLC), (Si-DLC / Me- DLC), in particular (Si-DLC / W-DLC) or (DLC / Si-DLC), (DLC / Me-DLC), in particular (DLC / W-DLC) or (Me-DLC / Si-DLC), in particular (W-DLC / Si-DLC), (Me-DLC / DLC), in particular (W-DLC / DLC) and, if appropriate, an intermediate layer arranged between the cover layer (6) and the layer system (30) and adjacent to the layer system (30) (4) from DLC, Si-DLC or Me-DLC, in particular from W-DLC and in the layer system (30, 4) the following material pairings are present:

Layer system (30) Mediator layer (4)

n x (Si-DLC / DLC)

nx (Si-DLC / DLC) Si-DLC nx (Si-DLC / DLC) Me-DLC

n x (Si-DLC / Me-DLC)

n x (Si-DLC / Me-DLC) Si-DLC

n x (Si-DLC / Me-DLC) DLC

n x (DLC / Si-DLC)

n x (DLC / Si-DLC) DLC

n x (DLC / Si-DLC) Me-DLC

nx (DLC / Me-DLC)

nx (DLC / Me-DLC) DLC

n x (DLC / Me-DLC) Si-DLC

n x (Me-DLC / Si-DLC)

n x (Me-DLC / Si-DLC) DLC

nx (Me-DLC / Si-DLC) Me-DLC

nx (Me-DLC / DLC)

nx (Me-DLC / DLC) Si-DLC

nx (Me-DLC / DLC) Me-DLC where n is an integer greater than or equal to 1 and Me-DLC is preferably designed as W-DLC.

20. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 19, characterized in that the workpiece (10, 11, 12, 13) one between the

Cover layer (6) and the base body (1) arranged and the cover layer (6) adjacent third mediator layer (5) of Me-DLC or DLC comprises.

21. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 20, characterized in that the base body (1) made of a material selected from steel,

Steel alloys, titanium, titanium alloys, aluminum, aluminum alloys, magnesium, magnesium alloys, copper, copper alloys, ceramics, tungsten carbide, tungsten, tungsten alloys, tantalum, tantalum alloys, nickel, nickel alloys, silicon, silicon compounds, bronze, plastic or a mixture of these materials.

22. workpiece (10, 11, 12, 13) according to one or more of claims 1 to 21, characterized in that the workpiece (10, 11, 12, 13) a motor part of an internal combustion engine, a transmission part of an automotive transmission, a Connecting rod, a gear part, a gear, a shaft, a bearing shell, a rolling bearing, a ball bearing, a needle bearing, a piston ring, a piston pin, a cylinder liner, a part of a fuel injection device, for example for the direct injection of diesel or gasoline for automobile engines, a part of the valve train of a car engine, a bucket tappet, a rocker arm, a rocker arm, a valve lifter, a linear guide, a locking handle for automobile doors, a sliding bushing or a solar cell.

23. A process for PVD coating of workpieces (1), comprising one or more steps S _t to S _N , where N = l, 2, 3, wherein in step S _N a Si-DLC, DLC, Me-DLC and hydrogen containing cover layer (6), wherein Me is selected from the group comprising Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Ni, W, by means of one or more simultaneously operated magnetron cathodes (50, 60, 70) with target (51, 61, 71), characterized in that one or more silicon-containing targets (51) with 20 to 100 atom% silicon are used, one or more targets (61) 20 to 100 atom% carbon, one or more targets (71) contain 20 to 100 atomic% Me and the deposition is carried out in an atmosphere (80) having a nominal hydrogen content of less than 30 atomic%.

24. The method according to claim 23, characterized in that one or more targets (51) of silicon, carbon, preferably in the form of graphite and optionally additives, one or more targets (61) of graphite and optionally additives, and one or more targets (71) consist of Me, in particular tungsten, carbon, preferably in the form of graphite and optionally additives.

25. The method according to claim 23 or 24, characterized in that one or more targets (51) made of graphite, embedded in the graphite moldings of silicon or silicon carbide and optionally additives, wherein the embedded moldings are preferably arranged uniformly in the region of the target erosion.

26. The method according to one or more of claims 23 to 25, characterized in that one or more targets (71) consist of graphite, embedded in the graphite moldings of Me or Me carbide and optionally additives, wherein the embedded moldings preferably uniformly in Range of target erosion are arranged.

27. The method according to claim 23, characterized in that one or more targets (51) made of graphite, embedded in the graphite moldings of silicon or silicon carbide embedded in the graphite moldings of Me or Me carbide and optionally additives, wherein the embedded Moldings are preferably arranged uniformly in the region of target erosion.

A method according to claim 23, characterized in that one or more targets (51) are selected from materials selected from SiC, a mixture of Si and SiC, a mixture of graphite and SiC, a mixture of graphite and Si, a mixture of graphite and Si and SiC, W, WC, Ti, TiC, V, VC, Cr, CrC, Zr, ZrC, Nb, NbC, Mo, Mo ₂ C, Hf, HfC, Ta, TaC, Ni or NiCx and optionally additives.

The method of claim 23 or 28, characterized in that one or more targets (71) are selected from materials selected from Me carbide, a mixture of Me and Me carbide, a mixture of graphite and Me carbide, a mixture of graphite and Me, a mixture of graphite and Me and Me carbide and optionally additives.

30. Method according to one or more of claims 23 to 29, characterized in that it comprises one or more steps Si to S _N - _I , where N = 2, 3, ..., wherein magnetron sputtering of one or more targets (51 , 61, 71, 111, 121, 131) of materials selected from graphite, W, WC, Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Si, Ni and SiC or a mixture of these materials in an inert or reactive, optionally hydrogen-containing plasma (80), an adhesive layer (2) and / or one or more intermediate layers (3), (4), (5) or layer systems (30), (40) are deposited.

31. The method according to one or more of claims 23 to 30, characterized in that in one or more of the steps Sj to S targets (51, 61, 71, 111, 121, 131) or gases containing a dopant, such as boron or sulfur.

32. Method according to claim 23, characterized in that unbalanced magnetron cathodes (50, 60, 70, 110, 120, 130) are used and / or a bias potential of up to -300 V, preferably from -50 to -200 V, and in particular from -100 to -200 V is applied.

33. The method according to one or more of claims 23 to 32, characterized in that prior to execution of the steps Sj to SN, the surface of the workpieces (1) is pretreated by means of ion etching, in particular with Ar ions.