Cathode arc source

Abstract

To provide a cathode arc vapor deposition apparatus.SOLUTION: There is provided a device that comprises: a target which has a surface as an active surface for evaporation; a confinement part which confines an outer border of the target surface; an anode which has an electron reception surface, and encircles the target and confinement part at an axial distance before a target plane and the active surface; and a magnetic guide system which provides a magnetic field with the target surface parallel with at least an outer region of the target surface with lines of magnetic force inclined in parallel with or at an acute angle α to the target surface and is defined within a surface region, wherein the lines of magnetic force enter the target surface at α≤45°. The confinement part and anode are formed in a closed geometric shape and electrically insulated from each other and the target, and an inner border of the electron reception surface is defined with at least one of a radial direction having a radial distance from the middle of the target, an axial distance from the target surface to an upper border of the confinement part, and an axial distance from the target surface to a lower border of the electron reception surface.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a cathodic arc deposition apparatus, a method for depositing a hard coating on a substrate, and a method for producing a coated substrate. [Background technology]

[0002] Cathodic arc evaporation equipment, also referred to herein as arc sources or arc evaporation sources, is well known in the field of physical vapor deposition (PVD) as a workhorse for numerous and varied surface treatment and coating deposition processes, particularly in the field of tool coating, and to some extent, in the field of component coating. However, despite their wide range of applications, arc sources suffer from some inherent drawbacks, namely the high heat load transferred from the surface of the arc source to the substrate and the high density of particles, commonly referred to as "droplets" or "macroparticles," that can result if the arc becomes clogged (i.e., if the arc spot lingers long enough on the target surface to be evaporated and target material from the target surface melts without the possibility of adequate evaporation and subsequent ionization), often leading to a molten pool that evaporates in an explosive manner, forming so-called droplets with dimensions of up to several micrometers that can be seen on the substrate surface and within the coating, especially on metal surfaces.

[0003] Until now, only filtered arc sources seemed to solve both problems, but such arc sources were extremely expensive due to their complex magnetic setup and lost many of the advantages of conventional arc sources, which were highly productive in terms of coating speed, rugged and easy to handle processes.

[0004] There are some promising developments in another source type, the so-called steered arc source, in which the arc is confined to a surface by a static or dynamic magnetic field and forced to move in a specific path at greater speeds than a random arc.

[0005] In Patent Document 1, Krassnitzer et al. propose an arc source, as shown in Figure 5, which allows the production of layers with low surface roughness at a consistently high deposition rate, and which comprises a cathode (target), an anode, and magnetic means that allow the magnetic field lines to connect the target surface to the anode in a short connection. In this way, the electron temperature of such a plasma is only about 0.3 eV to 1 eV, so that the behavior of the potential in front of the substrate is not distorted.

[0006] However, there is still a need for improvements particularly related to achieving a higher reduction in droplet formation in coatings produced by reactive cathodic arc evaporation processes, which do not require evaporating targets made of materials consisting of or containing a large proportion of chemical elements with low melting points, such as aluminum. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] International Publication No. 2011 / 160766 Summary of the Invention [Problem to be solved by the invention]

[0008] One of the objects of the present invention is to provide a new arc source that constitutes a solution for overcoming the above-mentioned problems of state-of-the-art arc sources. In particular, the present invention provides a new arc source that allows the coating of substrates by using reactive cathodic arc deposition techniques, so that the heat load on the surface of the substrate to be coated (and therefore the substrate temperature) can be kept as low as possible, while at the same time achieving a further reduction in the size and density of the droplets in the coating. [Means for solving the problem]

[0009] The objects of the present invention are achieved by providing an inventive arc source as described below.

[0010] The arc source (cathodic arc evaporation apparatus) according to the invention comprises a target as a cathode having a target front surface (hereinafter also simply referred to as target surface) of the material to be evaporated (the target surface to be evaporated is also referred to as active surface in the description of the present invention, the active surface being the target surface from which the material is subsequently evaporated during the cathodic arc evaporation process), a target back surface facing a target back plate arranged parallel to the target front surface but on the opposite side with respect to the target front surface, and a target side surface (hereinafter also referred to as boundary or target boundary) connecting the target front surface to the target back surface, and an electrically floating confinement member (hereinafter also referred to as confinement member or simply confinement section or electrically floating arc spot confinement section), which is preferably ring-shaped, although other configurations are also possible. For example, the confinement member may be square or rectangular, and the confinement member is positioned adjacent to, preferably surrounding or at least partially surrounding (but without direct contact with) the target side surface, and in particular the confinement portion is positioned surrounding the outer boundary of the target surface (this is particularly the case where the confinement portion is positioned surrounding the surface of the boundary of the target next to the target front surface), the electrically floating confinement member has an inner surface and an outer surface, the target side surface is closer to the inner surface of the confinement member than the outer surface of the confinement member, an electrode as an anode having an inner surface to function as an electron receiving surface, and magnetic field generating means (hereinafter also referred to as a magnetic guiding system or simply magnetic means) configured to provide a magnetic field with magnetic field lines positioned in front of the front target surface. The inner surface of the confinement member is positioned between the target front surface and the electron receiving surface of the anode when considering the distance in a vertical plane relative to the target front surface, and / or between the target side surface and the electron receiving surface of the anode when considering the distance in a parallel plane relative to the target front surface.The magnetic field generating means is designed and adjusted to generate at least two magnetic field regions: a first region with magnetic field lines located in front of the target front surface that emerge from the target front surface and terminate at the inner surface of the confinement member, and a second region with magnetic field lines located in front of the target front surface that emerge from the target front surface and terminate at the electron receiving surface of the anode, thereby making it possible to generate three plasma regions or plasma areas when the arc source is operated in the vacuum chamber, the first plasma region (plasma region A or bright plasma region A or high electron temperature plasma region A) being located in front of the target front surface in the first plasma region (plasma region B or dark plasma region B or low electron temperature plasma region B), electrons flow to the anode via magnetic field lines that exit the front target surface and terminate at the electron receiving surface of the anode, thereby closing the primary circuit; and in the third plasma region (plasma region C or dark plasma region C or low electron temperature plasma region C), there are no magnetic field lines that exit the front target surface and terminate at the inner surface of the confinement member, nor any magnetic field lines that exit the front target surface and terminate at the electron receiving surface.

[0011] Thus, with the arc source of the invention, a surprisingly large improvement is achieved, which simultaneously provides the following three advantages: a lower electron temperature in the plasma zones B and C, which leads to a lower thermal load on the substrate, favoring the coating or plasma treatment of substrates made of or equipped with a temperature-sensitive material, the formation of coating materials which require a lower temperature for their corresponding synthesis; a lower electron temperature in the plasma zones B and C, which therefore leads to a lower electron temperature in the plasma surrounding the substrate to be plasma treated or coated (usually plasma zone C); and a lower ionization of the reactive gas in zones B and C, which therefore leads to the possibility of the synthesis of a coating material, the synthesis of which is facilitated by a reduced or absent amount of reactive gas ions (for example, a lower amount of gas ions N, if nitrogen is used as the reactive gas). + and N 2+), the reactive gas ions react with the target front surface material, causing a change in the state of the target front surface material (e.g., if the target front surface material is a metal or metalloid and nitrogen is used as the reactive gas, the gas ions N + and N 2+ reacts with the metal or metalloid on the front surface of the target, causing nitridation of the target front surface material such that smaller and / or fewer droplets are produced (e.g., if the target material is Ti or Al or AlTi and nitrogen is the reactive gas, during nitriding of the target front surface a nitride layer of TiN or AlN or AlTiN is formed, leading to an increased steering speed of the arc spot traveling on the nitride layer, a reduced evaporation rate of the target front surface material, and fewer droplets being ejected, thereby depositing a coating on a substrate placed in region C exhibiting lower roughness (i.e., having a smoother surface)), accompanied by a significant reduction in the size and quantity of droplets in the coating resulting from the increased plasma density of reactive gas ions in plasma region A.

[0012] definition The term cathodic arc deposition apparatus is synonymous with the term arc source and is used in this application in the same manner as the term arc deposition source.

[0013] The terms radial (r1,...rn) and axial (h1,...hn) distances and higher and lower and their respective equivalents are used with reference to the arc source concept as shown in the figures unless otherwise noted. The terms inner and outer are used with reference to the axis or centerline Z of the arc source, Z defining the innermost position, unless otherwise noted. However, one skilled in the art will recognize that the arc source can be located anywhere in the vacuum chamber, meaning at the bottom, the side of the vacuum chamber, or overhead (not shown), and will interpret these terms accordingly with respect to the arc source as shown in the figures.

[0014] Surprisingly, it can be shown that the arc source of the present invention can also be used to deposit chemical compositions further away from thermodynamic equilibrium than can be provided by sources known from the state of the art, which is another object of the present invention.

[0015] More detailed and preferred embodiments of the cathodic arc evaporation apparatus according to the invention and the method in which at least one cathodic arc evaporation apparatus according to the invention is used are described in more detail below.

[0016] In a preferred embodiment of the cathodic arc evaporation device according to the invention, the device comprises a target having a target surface (above called the target front face) with an active surface (above called the surface to be evaporated) from which material can be evaporated in a cathodic arc process, a confinement part surrounding the outer boundary of the target surface, which may be a single-piece body or a confinement body made up of several confinement elements, an anode having an electron receiving surface, which surrounds at least one of the target and the confinement part in at least one axial distance in front of the target surface and the active surface, and which comprises at least 50%, or 70%, or even 90% or more of the target surface. a magnetic guiding system configured to provide a magnetic field at a target surface that is essentially parallel to at least an outer region of the target surface, where essentially parallel in this context means that the magnetic field lines are parallel to or inclined to the target surface at an acute angle α≦45°, or α≦30°, or even α≦25°, thereby defining an active surface area, and whose effectiveness as an electron trap, etc., as described in detail below, is greater with a higher degree of balance of the magnetic field at and near the target surface, e.g., in region A also seen below; and a central axis Z for a circular arc source, or a central plane Z' for a polygonal, e.g., rectangular, arc source.

[0017] Both the confinement and the anode are preferably formed in a closed geometric shape, for example as a ring or a polygon such as a rectangle, and both are electrically insulated from each other and from the target, and the minimum distance of the electron receiving surface from the active surface is determined by the following geometric parameters: the radial distance Δr of the outer boundary of the target surface to the inner boundary of the electron receiving surface 14 wherein the outer boundary of the target surface has a radial distance r1 from the middle of the target, and the inner boundary of the electron receiving surface is defined by a distance having a radial distance r4 from the middle of the target and at least one of an axial distance h1 or h2 from the target surface to the upper boundary of the confinement section or the lower boundary of the electron receiving surface, which distances can be viewed as effective axial distances with reference to the increase in discharge voltage of the arc source.

[0018] High plasma density can thereby be achieved during the cathodic arc process in front of the outer region of the target. Due to the essentially surface-parallel magnetic field and the floating potential created by the insulated confinement, most of the impinging electrons bounce back into the high-density plasma, where they are trapped and forced into a circular motion similar to the racetrack of a sputter target. Only if the electrons escape on the outermost magnetic field lines further into the confinement at axial distance h1 and radial direction r4 are they driven by the more significant magnetic field in the region between the electron receiving surface and the target surface toward the anode, which is typically at ground potential, where they are neutralized.

[0019] Thereby, the essentially parallel magnetic field can extend from the target active surface to at least one axial distance (h1 or h2) of the confinement or electron receiving surface, or can extend to a height of at least 5 to 20 mm above the target surface.

[0020] In any embodiment of the present invention, an active area A is provided that contains an essentially parallel magnetic field, and a magnetic flux density B AThe intensity of the magnetic field can be set at 20 to 500 Gauss or more, e.g., about 40 to 60 Gauss at the mid-diameter of the target surface, and about 500 Gauss or more within a few millimeters of a strong magnetic central limiter, if utilized. Region A is laterally limited by the outer boundary of the target active surface or by a confinement section that also limits the diameter. Relative to the target center, Region A is bounded either by the inactive surface region of the target where the magnetic field lines enter the target surface at angles >45°, as described below, or by a central limiter that can have the properties of a magnetic central yoke. Axial from the target, Region A is bounded by the last magnetic field line further into the confinement section, e.g., its lowest or innermost boundary, immediately before the next magnetic field line entering the electron receiving surface.

[0021] The containment section, as used for the central limiter, as shown below, can be made of magnetic or non-magnetic materials, such as magnetic steel, or non-magnetic steel, ceramic or other materials that can withstand high thermal loads near the target active surface.

[0022] The radial distance Δr between the outer diameter of the target active surface and the inner diameter of the electron receiving surface 14 is 5 to 30 mm, for example 20±5 mm. This distance can be seen as the effective radial distance with reference to the increase in the discharge voltage of the arc source.

[0023] The radial distance r1 from the centre of the device to the outer boundary of the target surface is between 80 and 220 mm, for example 15±5 mm.

[0024] The axial distance (h1 or h2) is from 0 to 20 mm, for example 15±5 mm.

[0025] The maximum axial distance h3 from the target surface to the electric receiving surface may be 10≦h3≦50.

[0026] The magnetic guidance system may comprise at least a central magnet having a pole located in front of the center of the rear surface of the target and axially aligned therewith, and a peripheral ring magnet having a reciprocal pole in or below the plane of the target, the ring magnet envisaging surrounding at least a portion of the central magnet and the target when overlapping, e.g., when the inner diameter of the ring magnet is smaller than the outer diameter of the target, and preferably otherwise surrounding the target as a whole.

[0027] At least one of the central magnet and the ring magnet may be an electromagnet or a permanent magnet. If a permanent magnet is used, each magnet may be made from a single piece or by arranging permanent magnets, for example, in a circular arrangement of the same poles as the ring magnet.

[0028] The magnetic axis of the ring magnet can be tilted upward and away from the central axis Z or plane Z'. The axis of the central magnet is usually central and parallel to the axis Z.

[0029] In another embodiment of the invention, the ring magnet may comprise two electromagnetic coils C2 and C3, with the diameter of C3 being larger than that of C2. Such coils may have separate coil yokes or a common coil yoke, as shown below, and may be mechanically or simply magnetically connected to the peripheral yoke.

[0030] The magnetic guiding system of any embodiment may further comprise a circumferential yoke surrounding the ring magnet, the target and the anode, the circumferential yoke being made of a magnetizable material, for example, iron, martensitic steel, or the like.

[0031] In another embodiment, the magnetic guiding system may further comprise a central limiter disposed in or around the center of the target surface, the central limiter being electrically insulated with respect to the target and having a Curie temperature T C >500℃, T C >600°C, or even T CThe central limiter is made of a magnetic material having a temperature of >650°C. The respective material may be, for example, a pure iron structural steel with a low carbon content or a ferritic corrosion-resistant steel with a Cr content of more than 10.5% by mass. Such a central limiter may have a width or diameter of 20 to 50 mm, for example 30 to 40 mm, and may be disk- or ring-shaped for a circular target.

[0032] The central limiter may, for example, protrude from 0 to 20 mm, or from 5 to 20 mm, above the target surface or further relative to the axial distance h1 or h2, if at least one of the confinement and the anode protrudes above the target surface.

[0033] Alternatively, the central limiter may be flush with the target surface. The central limiter may protrude 5 to 20 mm above the target surface or relative to the axial distance h1 or h2, for example, if at least one of the confinement and the anode protrudes into the target surface.

[0034] In any embodiment of the present invention, the containment portion may be made of a non-magnetic material.

[0035] In another preferred embodiment of the present invention, the minimum distance of the electron accepting surface from the active surface is the radial distance Δr 14 and defined by the axial distance h1 or h2.

[0036] The present invention is also directed to a vacuum chamber equipped with a cathodic arc evaporation apparatus, as described above.

[0037] The present invention further relates to a method for depositing a coating on a substrate in a vacuum chamber using a cathodic arc deposition apparatus as described above, wherein an electron trap is established at least immediately above the target surface in region A by applying an essentially parallel magnetic field with magnetic field lines entering the target surface at an acute angle α≦45° to at least an outer region of the target surface using a magnetic guidance system, thereby forming an active surface. The method further includes igniting and maintaining a cathodic arc discharge on the active surface, whereby the arc spot is steered by the parallel component of the radial magnetic field, and region A is laterally bounded by a confinement on a floating potential surrounding the target. Relative to the center of the target, region A can be bounded by either an inactive surface region of the target or a central limiter. Axial from the target, region A can be bounded by the last magnetic field line 9 entering the confinement at its upper boundary.

[0038] The method can further include forming a region B above region A by a distance h3, given by the maximum axial distance of the electron receiving surface from the target surface. More precisely, region B, from which electrons potentially escaping from region A can be propelled further in a circular path toward the anode by the current magnetic field, is bounded, for example, upward at its highest or outermost boundary, by a first magnetic field line 8' entering the electron receiving surface, e.g., starting at its lowest or innermost boundary immediately followed by magnetic field line 9, which constitutes the last magnetic field line further entering the trap at its upper or outermost boundary. Both magnetic field lines originate from a central magnet or central limiter. It is clear that the average magnetic field strength of region B is less than that of region A. However, the magnetic field strength and magnetic flux within region B are essentially higher than zero; for example, a magnetic flux of 5 to 20 gauss can be applied to efficiently drive electrons potentially escaping from the electron trap from region A toward the anode, laterally delimiting region B. At the anode, the electrons are discharged, leaving the plasma and therefore no longer available for further ionization or collision processes that heat the process gas or other parts of the vacuum chamber. Therefore, the heat load at the anode is fundamentally higher than in conventional arc sources, which can be managed by direct or indirect water cooling of the anode and the use of highly thermally conductive anode materials such as copper.

[0039] Here, a two-part or more anode can be used, for example, an anode with an inner anode ring extension that fits tightly onto the outer water-cooled anode body, allowing the inner ring to be easily removed or replaced for maintenance purposes. At the same time, the heat load at the substrate can be substantially reduced. On the one hand, an intense, bright arc plasma, in which a large proportion of the arriving reactive molecules, such as nitrogen or oxygen containing process gases, are immediately ionized, is confined to region A and does not extend into the vacuum chamber. This bright plasma can have a similar lateral distribution as seen in the so-called racetrack of the sputter target. This allows the target surface to be completely reacted—for example, nitrided, oxidized, or both nitrided and oxidized when nitrogen and oxygen containing process gases are used simultaneously. The high melting points of such compounds effectively suppress the undesirable formation of a liquid metal pool and its "explosive" evaporation in the arc track, which would otherwise lead to high densities of droplets distributing on the surface of the coated substrate. On the other hand, the electron heat is efficiently absorbed by the water-cooled anode. Tests measuring the temperature difference between the anode and target cooling water have shown that greater than 80%, greater than 90%, or even greater than 95% of the process energy supplied by the arc source can be discharged through the respective cooling circuits of the target and anode when the arc evaporation apparatus of the present invention is used. However, with conventional arc sources, only 50% to 55% of the heat is discharged through the respective cooling circuits, which means that the heat load on the substrate is reduced by about 90%, and substrate temperatures between 150°C and 350°C, and particularly between 150°C and 300°C, can be achieved without the need for separate cooling of the substrate.

[0040] The method may further comprise, referring to the deposition process in a vacuum chamber, forming a region C above regions A and B between the arc source and the substrate surface to be coated, wherein the magnetic field is very low or zero, and the atmosphere contains reactive gas molecules and at least one of positively ionized metal ions and positively ionized reacted metal ions. Optionally, the atmosphere may further contain at least one inert gas molecule. The proportion of ionized reactive gas molecules in region C is very low or negligible relative to the high ionization in region A. Thereby, the reactive gas molecules and positively ionized metal ions and / or positively ionized and reacted metal ions are significant and, in one example, may form at least 80%, e.g., 95%, or even 99% or more of the reactive atmosphere in which the substrate is submerged.

[0041] With the aid of the magnetic guiding system and the floating confinement, which both act like a plasma resistor, which can be adjusted by the magnetic field strength and the distances r4, h1 and / or h2, the discharge voltage of the arc source can be increased to between 20 V and 50 V, between 25 V and 40 V, or between 30 V and 35 V to generate strong ionization of the working gas near the target surface. This is essentially above the discharge voltage of known arc sources, which are usually driven with a maximum discharge voltage of 10 V to 20 V.

[0042] To summarize, with the use of the arc source of the present invention, the deposition process can be designed with a high plasma density confined to region A just above the surface of the substrate, thereby providing high reaction of the target surface with the reactive process gas. In region B, electrons can be efficiently removed before exiting towards free space in the vacuum chamber. At the same time, reactive gas ions coming from region A can recombine in region B and / or at the anode surface. Thus, region C is essentially devoid of free electrons, i.e., electrons not bound to molecules or metal ions, and the reactive gas ion concentration is low or close to zero. Referring to the loaded particles, the reactive gas ions are essentially relatively heavy metal ions (Men+ ) and metal compound ions, e.g., MeM n+ and / or MeO n+ Many of these can be detected in region C, where they, along with reactant gas molecules, can react with the incoming metal ions or metal containing ions on the substrate surface to provide the deposited material. Other charged species such as electrons and nitrogen ions are mostly confined to regions A and B, near the target surface, with high densities in region A.

[0043] Such plasma modifications make the source highly suitable for the low-temperature deposition of hard coatings and processes to deposit compound compositions from a state of thermodynamic equilibrium. As an example, AlMeN, AlMeO, or AlMeNO compounds of different stoichiometric compositions can be deposited, where Me represents one or more metals of transition metal groups IV, V, or VI (US: groups 4b, 5b, 6b), including Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, and W. As an example of such a coating, mention should be made of the deposition of cubic TiAlN, which can be deposited in the pure cubic phase with concentrations of 70% and 80% Al. The percentages refer to the metal content of the compound, i.e., (Al 0.7 Ti 0.3 )N or (Al 0.8 Ti 0.2 )N. Reactant elements may be in stoichiometric, sub- or over-stoichiometric concentrations with reference to the metal composition.

[0044] The invention will now be further illustrated by means of the drawings. [Brief explanation of the drawings]

[0045] [Figure 1] FIG. 1 is a simplified schematic diagram of a first embodiment of the device according to the invention. [Figure 2] FIG. 2 shows a second embodiment of the device according to the invention. [Figure 3] FIG. 3 shows a third embodiment of the device according to the invention. [Figure 4]FIG. 4 shows a fourth embodiment of the device according to the invention. DETAILED DESCRIPTION OF THE INVENTION

[0046] FIG. 1 shows, in its most schematic and simplified form, one embodiment of an arc source I according to the present invention, including a planar target 3 having a radial width or diameter r1, a respective confinement 4 surrounding the target, and an anode 2 surrounding both the target and the confinement. The target may be polygonal, e.g., rectangular, or circular, with Z thus defining the central plane or axis of the target. Hereinafter, for ease of understanding, the target will be referred to as a circular, and with reference to FIGS. 3 and 4, a ring-shaped target; however, these dimensions can be easily translated to other planar targets, i.e., targets having flat surfaces of different shapes to be evaporated, within the scope of the present invention. Also referring to FIGS. 3 and 4, due to the nested configuration of the arc source from FIG. 1, the inner diameter r2 of the confinement is typically larger than the outer diameter r1 of the target 3, or at least larger than the outer diameter of the target active surface 3′, for example, if the confinement is configured to protrude the target surface by several millimeters (not shown) and create an arc extinction distance upward instead of laterally, as shown in the figures. These distances, r2-r1, should be in the range of 1.5 to 3 mm to ensure that the electric arc traveling on the target surface cannot slowly advance into the gap formed between the target and the confinement or extend to the confinement surface. At the same time, the generation of undesired parasitic plasma in the gap can be avoided. Similar distances can be selected for the distance r4-r3 between the outer diameter r3 of the confinement 4 and the inner diameter r4 of the anode, or for the respective axial distances h2-h1 of the confinement 4 to the anode 3, as shown in FIG. 2, or in modified anode geometry 2''' as shown in FIG. 1 by the dashed line. This effectively avoids electrical contact and undesired plasma formation between the electrically isolated confinement and the anode.

[0047] In the region where the magnetic field lines enter the target surface, the so-called active surface 3', at an acute angle α≦45°, an electric arc can be ignited and circularly steered by the radial magnetic field. This allows the formation of a highly luminous plasma 10 (hereinafter also referred to as reactive gas plasma), which effectively dissociates reactive gas molecules, such as nitrogen-, oxygen-, or carbon-containing gases, entering this region into their atomic and ionic components, thereby helping to react with the metal target active surface or metal ions or clusters departing from the arc traveling on the surface. Thus, most of the possible reactive plasma processes, such as nitriding, oxidation, carbonization, or processes with mixed reactive gases, can occur at or near the target surface within region A, which is located in the region between the last magnetic field lines 9 further into the containment and the target surface 3, particularly the target active surface 3' formed in the outer surface region in the embodiment shown in FIGS. 1 and 2. Region A can also be viewed as an electron trap, assuming that electrons are reflected from the confinement wall surfaces and can only escape from the plasma if they reach region B between magnetic field lines 9, 8' and 8, respectively, where magnetic field lines 8 enter the electron receiving surface at their highest or outermost boundary and magnetic field lines 8' enter the electron receiving surface at their lowest or innermost boundary, just above magnetic field lines 9, as shown in FIG. 2. In region B, the electrons are neutralized at anode 2. The electron receiving surfaces 2', 2'', 2''' of anode 2 can be geometrically different, e.g., simply cylindrical 2', and / or differently inclined, e.g., with respect to axis Z, as shown by dashed line 2'', or protruding above at least a portion of confinement 4, as shown by dashed line 2''' in FIG. 1. The anode further comprises an anode cooling channel 6', which can be connected to a dedicated or common, e.g., water-based, cooling line, not shown.

[0048] Similar to the electron receiving surface defined by the inner and / or upper surface of the anode, the inner and / or upper surface of the containment portion 4 may be geometrically different, e.g., simply cylindrical 4', and / or may be, e.g., at least partially, differently inclined relative to the axis Z as shown by dashed line 4'' or projecting beyond the target surface as shown by dashed line 4'''.

[0049] All arc sources of the present invention further comprise a magnetic guidance system configured to provide a magnetic field in front of the target surface that is essentially parallel to at least the outer region of the target surface, as in the embodiments shown in FIGS. 1 and 2, or over the entire target surface, as in the embodiments shown in FIGS. 3 and 4. Essentially parallel here means that the magnetic field lines enter the target active surface at an acute angle α≦45°, or at a more acute angle α≦30° or α≦25°. Such a magnetic guidance system, as exemplarily shown in FIGS. 3 and 5, can also be used in any other embodiment of the arc source of the present invention, for example, in embodiments 1 and 2, which typically comprise a central magnet 14 and a ring magnet 15, the latter surrounding the central magnet and, optionally, at least envisioned, the target 3. A ferromagnetic peripheral yoke 17 at ground potential may also help in any embodiment to further shape the magnetic field, e.g., limit the radial expansion of the magnetic field lines.

[0050] Figure 2 shows an embodiment of the invention of arc source II with a cylindrical anode 2 located on top of a cylindrical confinement, both of which have the same inner diameter. In this case, essentially only the distance h2 contributes to increasing the discharge voltage of the arc source, whereas in all other embodiments, as shown in the other figures, the axial distance h1 or h2 and the radial distances r5-r2 contribute. The latter distances are largely negligible in Figure 2, since they are reduced to the gap between the target and the confinement.

[0051] In another embodiment not shown, the confinement is formed as a ring surrounding the target at the target surface level, and the anode is formed as a ring surrounding both at the same level. In this case, essentially, only the radial distances r4 to r1 contribute to the increase in the discharge voltage of the arc source when the inner confinement surfaces 4', 4'', 4''' and the inner electron receiving surface are completely exchanged with the respective upper confinement and anode surfaces when placed at the same level as the target surface 3.

[0052] FIG. 3 shows an arc source III similar to FIG. 1 with a basic magnetic guide system with a central permanent magnet 14 having its magnetic axis Mc collinear with the central axis Z, and a ring magnet 15 with its magnetic axis M r is tilted upward away from the central axis Z or plane Z. The magnetic axis M relative to the central axis Z r The tilt angle can be between 0 and 45°, e.g., between 5 and 30°, depending on the specific situation. Here, the magnetic section lines are also affected and tilted, thereby achieving a flatter or more parallel path for the magnetic field lines on the target surface. In this context, the section lines are the planes between, on the one hand, the magnetic field lines running from one pole, here the south pole of the ring magnet, to the opposite pole, here the north pole of the central magnet, and, on the other hand, the magnetic field lines running from one pole of the ring magnet to the opposite pole of the same ring magnet. Those skilled in the art will recognize that the magnetic poles can be interchanged. For example, a ferromagnetic peripheral yoke 17 at anode potential, usually ground potential, can be used to make the magnetic field lines more parallel on the target surface and to shield the magnetic field radially outside the peripheral yoke that laterally surrounds the entire arc source. In FIG. 3, the central magnet 3 is located directly below the target back plate 12, which is equipped with target cooling channels that can be connected to dedicated or common, e.g., water-based, cooling lines (not shown). Alternatively, the central magnet can also be located within the rear plate 12, for example within the cooling channel 13.

[0053] Additionally, a Type III or IV arc source, as shown below in Figure 4, includes a ferromagnetic central limiter 16 at an electrically floating potential at or in the center of the target 3. The yoke 16 is therefore mounted on an isolator 19 of an electrically insulating and heat-resistant material such as ceramic, as well as a floating-mounted containment 4 mounted with the aid of at least one electrical isolator 20. The gap between the central limiter 16 and the target should be of the dimensions described above for the containment 4, ranging from 1.5 to 3 mm.

[0054] With the help of the central limiter 16, the magnetic field lines f are symbolically shown. m can be formed essentially parallel to the entire target surface 3'. This also allows the target active surface 3'' to extend over the entire surface 3', in this case a surface ring. Due to the high heat load in the middle of the target, any central limiter 16 in any embodiment must have a high Curie temperature T, preferably above 600°C. C The magnetic material must have a magnetic permeability μ r The magnetization should be at least 100 or even 500, and the saturation magnetization should be higher than 0.3 Tesla, even higher than 0.5 Tesla. Such materials have low remanence B, especially when magnetic steering of the arc requires a dynamic magnetic field. r For example, when the magnetic coils are driven with a variable, e.g., pulsed, current, the respective coercive forces H C should be lower than or equal to 200 A / m or lower than 50 A / m.

[0055] An example of such a material is C Pure iron, such as ARMCO® iron, has a T of about 768°C. C Structural steels with low carbon content, such as S235 or S355 steels, or low Si concentrations of 0.30 to 0.70 wt. % and a T of 671°C. C or a high Si concentration of 1.00 to 1.50 mass% and a T of 660°C CThe magnetic properties of the peripheral yoke 17 are the same, but once the yoke is removed from the hot target surface, austenitic steels and other less expensive magnetic materials with the respective properties can be used with much lower Curie temperatures.

[0056] Similar to Figure 3, an arc source with a strong magnetic central limiter is shown in Figure 4, here in the most simplified schematic vacuum chamber 1 with a substrate 7 mounted above the arc source IV. Contrary to the Type III arc source of Figure 3, which uses permanent magnets, the magnetic guidance system of the Type IV arc source utilizes electromagnets C1, C2, C3, with magnet 14 realized by electromagnetic coil C1 with central coil yoke 18, and ring magnet 15 realized by coils C2 and C3 and outer coil yoke 21.

[0057] FIG. 4 shows a realized industrial arrangement of the arc source type IV of the invention with an electromagnetic guide system, in which the magnetic field lines are guided by the magnetic field H generated by the coils C1, C2 and C3. C1 , H C2 and H C3 The actual magnetic field lines that can be generated in such a system are the overlap of the magnetic field lines M and M. The central magnet 14 includes an electromagnetic coil C1 and a central coil yoke 18, and the ring magnet 15 includes electromagnetic coils C2 and C3 and an outer coil yoke 21. To generate such a magnetic field, the magnetic axis M r and each section line of the ring magnet 15 is tilted upwardly away from the central axis Z by applying a higher current to C2 than to C3, where I C2 >I C3 Alternatively, such an effect can also be seen with different windings N, e.g. N C2 >N C3The anode is a two-part anode having an anode body 25 with cooling channels 6 and an inner ring-shaped extension 26. A vacuum seal 22 clamps the vacuum chamber 1 against the atmosphere and water from the cooling circuits 6, 13. The substrate 7 can be attached to a substrate support (not shown) by known methods, e.g., by rotation. Regions A, B, and C are approximately separated from each other by magnetic field lines 8 and 9, as shown. With this configuration, a rarefied arc source with an outer diameter of 220 mm can be realized with a target diameter of 130 mm and a 36 mm strong magnetic center limiter. The total height from the backside of the target 3 to the upper boundary of the electron receiving surface 2 is approximately 53 mm.

[0058] In an industrial environment using Oerlikon batch coating equipment with a coating height of 1000 mm, up to 24 Type IV arc sources can be installed in four rows, each with six arc sources spaced meter apart, allowing for the deposition of AlMeN and AlMeNO type hard coatings at high speeds and high aluminum contents on various substrates. Pure cubic phase compounds can be deposited with aluminum contents ranging from zero to 85%, particularly high aluminum concentrations between 70 and 85%, in combination with at least one of Ti and Cr, for example. The chamber diameter of such equipment is 1000 mm, with a carousel of 700 mm diameter and 2000 mm chamber height. Of the substrates mounted with one, two, and three rotations, the closest substrate to the target distance is approximately 300 mm. Similar tests were conducted on the applicant's present invention and another industrially available coating system of the inventive type. Thereby, industrial applicability can be tested with a usable coating height of 500-1500 mm for the following chamber dimensions: chamber diameter of 500-1200 mm, carousel diameter of 300-900 mm, chamber height of 1000-2000 mm.

[0059] Below are listed the properties and geometric data of certain core components of the arc source of the present invention.

[0060] The target can be cooled directly or via a bonded back plate, depending on the strength of the respective materials. Both types can be mounted on a water-cooled cathode electrode. Circular diameter D T , 60mm≦D T =2r1≦200mm, 100mm≦D T = 2r1 ≦ 150 mm. The material can be any solid material suitable for arc evaporation.

[0061] The containment is mounted and insulated between the target and the anode, so that a potential between the cathode target potential and the positive or grounded anode potential is induced during the cathodic arc process. CI , 95≦D CI = 2xr2≦155mm, for example, 132mm. Thickness t in the radial direction (r3 to r2) CR is 10≦t CR ≦30mm, for example, 148mm, thickness t CR It should be noted that refers only to the surface area of ​​the confinement rings that can be exposed to the arc plasma; the total thickness extension of the confinement rings may be greater depending on the configuration of the particular arc source, for example, if the anode extensions overlap, thereby protecting the outer portions of the confinement rings from interaction with the plasma. The distance h1 from the active surface to the upper surface or top of the confinement rings (in planar embodiments) satisfies 0≦h1≦20, and in the preferred range for cylindrical and combined embodiments, e.g., FIGS. 1 to 4, satisfies 10≦h1≦30, e.g., 15≦h1≦25. The radial distance of the confinement rings, at least in the region where they surround the target in the target plane, is typically the distance d D = r3 - r2 = r4 - r5 = h2 - h1, where 1.5 mm ≤ d DA distance of ≦3 mm is effective, as this distance is compatible with dark space distances at normal process pressures, thereby preventing the arc spot from expanding into the containment and parasitic plasma between source components. Materials include ferromagnetic materials such as iron, carbon steel, etc., as well as non-magnetic metals, such as stainless steel, that have melting points high enough to withstand the high heat load of the adjacent arc discharge.

[0062] The internal water-cooled anode is set at a positive or ground potential. The inner diameter D defines the inner diameter of the electron receiving surface. AI , 80mm≦D AI =2xr4≦220mm, 120mm≦D AI = 2xr4≦170mm or approximately 150mm. Radial thickness t AR is 10≦t AR ≦40 mm. The distance h2 from the active surface to the top of the electron receiving surface or confinement ring (e.g., in planar embodiments) satisfies 0≦h1≦50, with a preferred range for cylindrical and combined embodiments being 10≦h1≦35, and h2 may be the same as h1 when the confinement is nested within the anode, e.g., when the anode has electron receiving surfaces 2′, 2″ according to FIGS. 1 and 3. The material may be copper, carbon steel, or stainless steel.

[0063] The total geometry of the cathode assembly satisfies the following: diameter in the range 150 mm (for example, for cylindrical variations)≦DSource≦290 mm (for example, for planar variations), or 180 mm≦DSource≦260 mm.

[0064] The magnetic guidance system for generating the magnetic field has a high parallel component at least near the top of the outer region of the target active surface. The means includes a guidance system located in front of the rear surface of the target, for example on the back plate of the cathode electrode, and electrically isolated from the electrode. The guidance system can optionally be assisted by an electrically isolated ferromagnetic central limiter mounted (at floating potential) at the center of the target surface and / or peripheral yoke.

[0065] For the ferromagnetic central limiter, the circular diameter D Y , 15mm≦D Y The thickness satisfies the condition of ≦50 mm, for example 36 mm. Materials include pure iron, low carbon content construction steel, and ferritic corrosion resistant steel, see above for details.

[0066] The magnetic field that can be set by the source of the present invention should be essentially parallel to and close to the target active surface, at least in the outer region of the target active surface. The formation of three sections (A, B, C) during the cathodic arc process possible with magnetic flux density is shown in B. A >B B >B C See above for details.

[0067] The arc source supply may be, for example, a DC supply carrying a discharge current of 10 to 200 A, for example 40 to 120 A per source. Alternatively, a DC supply with a pulsed arc supply or a multi-layer pulse supply may be used.

[0068] It should be mentioned that contrary to state of the art sources which are operated with a discharge voltage between 12 and 20 V, the source of the present invention can be operated with a discharge voltage between 20 and 50 V, e.g. between 25 and 40 V or even between 30 and 35 V due to the higher resistance of the electron traps which can be formed in region A due to the geometry, materials and magnetic means of the arc source.

[0069] Finally, any combination of features described in one embodiment, example or type of invention may be combined with any other embodiment, example or type of invention, unless inconsistent.

[0070] Specifically, the present application: The target front surface of the material to be evaporated, i.e., the target active surface a target back surface that is parallel to the target front surface but faces a target back surface plate located on the opposite side of the target front surface; and Target side that connects the front of the target to the rear of the target a target as a cathode having an electrically floating confinement disposed adjacent to, preferably surrounding or at least partially surrounding, the target side, the confinement having an inner surface and an outer surface, the target side being closer to the inner surface of the confinement than to the outer surface of the confinement; an electrode as an anode having an inner surface that functions as an electron receiving surface; a magnetic guiding system configured to provide a magnetic field with magnetic field lines located in front of the target face, The inner surface of the containment section is such that, when considering the distance in a vertical plane relative to the target front surface, it is between the target front surface and the electron receiving surface of the anode, and / or When considering the distance of a parallel plane relative to the front surface of the target, it is located between the side surface of the target and the electron receiving surface of the anode, The magnetic guiding system is designed and adjusted to generate at least two magnetic field regions: a first region with magnetic field lines located in front of the target front surface that emerge from the target front surface and terminate at the inner surface of the confinement member, and a second region with magnetic field lines located in front of the target front surface that emerge from the target front surface and terminate at the electron receiving surface of the anode.

[0071] The apparatus preferably includes an electrically floating ferromagnetic central limiter (16) for modifying the trajectory of the magnetic field lines emanating from the front surface of the target to be essentially parallel to the plane of the front surface of the target.

[0072] The present invention also relates to a method for operating the device of the present invention, wherein during operation of the device in a vacuum chamber, three plasma regions or plasma areas are generated, the first plasma region comprises electrons exiting the target front surface and crossing the magnetic field without having access to the anode due to magnetic field lines terminating at the inner surface of the confinement member; In the second plasma region, electrons emerge from the front surface of the target and are swept to the anode by magnetic field lines that terminate at the electron-receiving surface of the anode. In the third plasma region, there are no magnetic field lines that exit the target front surface and terminate at the inner surface of the confinement member, nor do there exist magnetic field lines that exit the target front surface and terminate at the electron receiving surface.

[0073] Preferably, the electron temperature resulting from carrying out the above method is between 1 eV and 5 eV in the first plasma region and between 0.3 eV and 1 eV in the second and third plasma regions.

[0074] The method of the present invention preferably includes at least one step in which a reactive gas is introduced into the vacuum chamber and the apparatus is operated while the reactive gas is introduced into the vacuum chamber, wherein the first plasma region contains more reactive gas ions than the second plasma region and the third plasma region, and thus the reactive gas ion density in the first plasma region is higher than the reactive gas ion density in the second and third plasma regions.

[0075] In a preferred embodiment of the method, the target or at least the front surface of the target is made of a metallic material and the reactive gas reacts with the metallic material from the target to produce a layer comprising elements from the reactive gas and elements from the metallic material.

[0076] According to a further preferred embodiment, the target consists of or comprises Ti or Al or Al and Ti and the reactive gas is or comprises nitrogen, whereby the layer resulting from the reaction of the reactive gas with the metallic material from the target is a nitride layer consisting of or comprising TiN or AlN or AlTiN, respectively.

[0077] According to a more preferred embodiment, the elemental composition AlxTi, where x is the atomic concentration fraction of Al. 1-xA target material is selected that consists of or includes Al and Ti in concentrations that allow for the synthesis of a coating on a substrate disposed within the third plasma region, the target material consisting of or including cubic aluminum nitride with N, where X is 0.8.

[0078] In a more detailed embodiment of the cathodic arc evaporation apparatus of the present invention, The apparatus comprises a target (3) having a target surface (3') with an active surface (3'') capable of evaporating material in a cathodic arc process; a containment portion (4) surrounding the outer boundary of the target surface (3'); an anode (2) having an electron receiving surface (2', 2'', 2''') surrounding at least one of the target (3) and the confinement portion (4) in at least one of the target plane and an axial distance in front of the active surface; a magnetic guiding system configured to provide a magnetic field at a target surface that is essentially parallel to at least an outer region of the target surface, such that the magnetic field lines are parallel to the target surface or inclined thereto at an acute angle α, wherein the active surface (3'') is defined in a surface (3') region where the magnetic field lines enter the target surface at an acute angle α≦45°; It has a central axis Z or a central plane Z', Both the confinement (4) and the anode (2) are formed in a closed geometry, both are electrically insulated from each other and from the target, and the minimum distance of the electron receiving surface (2', 2'', 2''') from the active surface (3'') is the radial distance Δr of the outer boundary of the target surface (3') to the inner boundary of the electron receiving surface. 14 the outer boundary of the target surface (3') has a radial distance r1 from the center of the target, and the inner boundary of the electron receiving surface has a radial distance r4 from the center of the target at a radial distance Δr 14 and at least one of an axial distance h1 from the target surface (3') to an upper boundary of the containment section, or an axial distance h2 from the target surface (3') to a lower boundary of the electron receiving surface (2', 2'', 2''').

[0079] The device of the present invention according to any of the preferred embodiments described above is preferably adjusted so that the essentially parallel magnetic field extends from the target active surface (3') to at least an axial distance (h1, h2) of the confinement or electron receiving surface and / or extends at least to a height of 5 to 20 mm above the target surface.

[0080] In region A on the target active surface, magnetic flux density B A The intensity can be set from 20 to over 500 Gauss.

[0081] The containment portion can be made of magnetic or non-magnetic materials.

[0082] Radial distance Δr 14 is preferably 5 to 30 mm.

[0083] The radial distance r1 from the centre of the device to the outer boundary of the target surface is preferably between 40 and 110 mm.

[0084] The radial distance (h1, h2) is preferably 0 to 20 mm.

[0085] The maximum axial distance h3 of the electron receiving surface is preferably 10≦h3≦50.

[0086] The magnetic guidance system preferably includes at least a central magnet having a pole located in front of the center of the rear surface of the target and axially aligned therewith, and a peripheral ring magnet having a reciprocal pole in or below the plane of the target, the ring magnet envisioned to surround the central magnet and at least a portion of the target.

[0087] At least one of the central magnet and the ring magnet is preferably an electromagnet or a permanent magnet.

[0088] The magnetic axis of the ring magnet is preferably tilted upwardly and away from the central axis Z or plane Z'.

[0089] In a preferred embodiment, the ring magnet comprises two electromagnetic coils C2 and C3, the diameter of C3 being larger than the diameter of C2.

[0090] In another preferred embodiment, the magnetic guiding system further comprises a circumferential yoke surrounding the ring magnet, the target and the anode, the circumferential yoke being made of a magnetizable material.

[0091] The magnetic guiding system further includes a central limiter disposed in or around the center of the target surface, the central limiter being electrically insulated from the target and having a Curie temperature T C It is preferably made of a magnetic material with a temperature >500°C.

[0092] In a preferred embodiment, the central limiter protrudes from 0 to 20 mm above the target surface or relative to the axial distance h1 or h2.

[0093] In another preferred embodiment, the central limiter is flush with the target surface.

[0094] In a preferred embodiment, the containment portion is made of a non-magnetic material.

[0095] In another preferred embodiment, the minimum distance of the electron receiving surface (2′, 2″, 2′″) from the active surface (3′) is the radial distance Δr 14 and defined by the axial distance h1 or h2.

[0096] The present invention also relates to a vacuum chamber equipped with an inventive cathodic arc evaporation apparatus according to any one of the embodiments of the invention described above.

[0097] The present invention also relates to a method for depositing a coating on a substrate in a vacuum chamber by using a cathodic arc evaporation apparatus according to one of claims 1 to 18, wherein an electron trap is established at least immediately above the target surface in a region A by applying an essentially parallel magnetic field with magnetic field lines entering the target surface at an acute angle α≦45° to at least the outer region of the target surface (3) by using a magnetic guiding system, whereby an active surface (3″) is formed and a cathodic arc discharge is ignited and maintained on the active surface, the region A being laterally bounded by a confinement at floating potential.

[0098] Region B is preferably formed above region A to approximately an axial distance h3 given by the maximum axial distance of the electron receiving surface from the target surface.

[0099] Region C is formed above regions A and B, the magnetic field is very low or zero, and the atmosphere preferably contains reactive gas molecules and at least one of positively ionized metal ions and positively ionized reactive metal ions.

[0100] In a preferred embodiment of the method of the present invention described above, the cathodic arc discharge is maintained at a discharge voltage between 20V and 50V.

[0101] In one preferred embodiment of the method of the present invention, the coating is an AlMeN, AlMeO or AlMeNO compound, where Me represents one or more metals of transition metal groups IV, V or VI.

[0102] The present invention also relates to a method for producing a substrate coated by a deposition process according to any one of the embodiments of the invention described above.

[0103] In a preferred embodiment, the coated substrate is a tool or component. [Explanation of symbols]

[0104] 1. Vacuum chamber 2 Anode 2', 2'', 2''' electron receiving surface of anode 3. Target 3' target surface 3'' target active surface 4. Confinement section on electron floating potential 4', 4'', 4''' Inner surface of the containment 5 Arc Discharge Supply 6 Cooling channel anode 7 (biased / unbiased) substrate 8, 8' Magnetic field lines relative to the anode 9 Magnetic field lines relative to the confinement section 10 Gas Plasma 11 Gas inlet (N2, O2, CH4, C2H2, Ar) 12 Target back plate 13 Cooling Channel Back Plate 14 Center magnet 15 ring magnets 16 Electrically floating ferromagnetic center limiter 17. Ferromagnetic peripheral yoke at ground potential 18 Center coil yoke 19 Center limiter isolation device 20 Confinement isolation device 21 outer coil yoke 22 Seals 23 Electrical isolation device for target 24 Anode base 25 Anode extension 26 A part of the chamber or a component of or within the chamber, for example a flange or part of a flange, which is preferably electrically connected to the anode so as to have the same potential. C1, C2, C3 Electromagnetic coils 1, 2, 3 h1 axial distance from the active surface 3' to the upper boundary of the confinement section 4 h2 is the axial distance from the active surface 3' to the lower boundary of the electron receiving surface 2', 2'', 2'', which can be the same as h1, for example, as shown in the left electron receiving surface 2', 2'' in FIG. h3 Axial distance from the active surface 3' to the upper boundary of the electron receiving surface 2', 2'', 2''' M magnetic axis r1 is the radial distance from the central axis for a circular target 3, or the radial distance from the central plane for a polygonal, e.g., rectangular, target 3 r2 Radial distance from the central axis / plane to the inner diameter / boundary of the confinement section 4 r3 Radial distance from the central axis / plane to the outer diameter / boundary of the confinement section 4 r4 Radial distance from the central axis / plane to the inner diameter / boundary of the electron receiving surface 2', 2'', 2'' r5 Radial distance from the central axis / plane to the outer diameter / boundary of the electron receiving surface 2', 2'', 2'' r6 Radial distance from the central axis / plane to the outer boundary of the arc source The center plane or axis for each circular target of the Z polygon

Claims

1. a target as a cathode having a target active surface which is a target front surface of a material to be evaporated, a target rear surface which faces a target rear plate arranged parallel to the target front surface but opposite the target front surface, and a target side surface which connects the target front surface to the target rear surface; an electrically floating confinement disposed adjacent to, preferably surrounding or at least partially surrounding, the target side, the confinement having an inner surface and an outer surface, the target side being closer to the inner surface of the confinement than to the outer surface of the confinement; an electrode as an anode having an inner surface to act as an electron receiving surface; a magnetic guidance system configured to provide a magnetic field with magnetic field lines located in front of the target front surface; A cathodic arc evaporation apparatus comprising: an inner surface of the containment section is disposed between the front surface of the target and the electron receiving surface of the anode in a plane perpendicular to the front surface of the target, and / or between the side surface of the target and the electron receiving surface of the anode in a plane parallel to the front surface of the target, the magnetic guiding system is designed and adjusted to generate at least two magnetic field regions: a first region located in front of the target front surface with magnetic field lines emanating from the target front surface and terminating at the inner surface of the confinement member; and a second region located in front of the target front surface with magnetic field lines emanating from the target front surface and terminating at the electron receiving surface of the anode.

2. 2. The apparatus of claim 1, further comprising an electrically floating ferromagnetic center limiter (16) for modifying the trajectory of magnetic field lines emanating from said target front surface to be parallel to the plane of said target front surface.

3. 3. A method for operating a device according to claim 1 or 2, comprising: three plasma regions are generated during operation of the apparatus within a vacuum chamber; a first plasma region comprising electrons crossing the magnetic field without having access to the anode due to magnetic field lines emanating from the target front surface and terminating at the inner surface of the confinement member; In a second plasma region, electrons are caused to flow to the anode by magnetic field lines that originate from the front surface of the target and terminate at the electron-receiving surface of the anode; a third plasma region in which there are no magnetic field lines emanating from the target front surface and terminating at the inner surface of the confinement member, and no magnetic field lines emanating from the target front surface and terminating at the electron receiving surface.

4. 4. The method of claim 3, wherein the electron temperature in the first plasma region is between 1 eV and 5 eV, and the electron temperature in the second plasma region and the third plasma region is between 0.3 eV and 1 eV.

5. 5. The method of claim 3 or 4, comprising at least one step of introducing a reactive gas into the vacuum chamber and operating the apparatus while the reactive gas is introduced into the vacuum chamber, wherein the first plasma region contains more reactive gas ions than the second plasma region and the third plasma region, such that the reactive gas ion density in the first plasma region is higher than the reactive gas ion density in the second and third plasma regions.

6. 6. The method of claim 5, wherein the target, or at least the front surface of the target, is made of a metallic material, and the reactive gas reacts with metallic material from the target to produce a layer containing elements from the reactive gas and elements from the metallic material.

7. The method according to claim 6, characterized in that the target contains Ti, Al, or Al and Ti, and the reactive gas is nitrogen or contains nitrogen, so that the layer obtained from the reaction of the metal material from the target with the reactive gas is a nitride layer containing TiN, AlN, or AlTiN.

8. the material of the target is selected to consist of or include Al and Ti in concentrations that allow synthesis of a coating on a substrate disposed within the third plasma region, the coating having an elemental composition Al, where x is the atomic concentration fraction of Al; ｘ Ti １－ｘ 8. The method of claim 7, wherein the aluminum nitride is made of or comprises cubic aluminum nitride having N, and x is 0.

8.

9. 3. The device according to claim 1 or 2, a target (3) having a target surface (3') with an active surface (3'') from which material can be evaporated in a cathodic arc process; a containment portion (4) surrounding the outer boundary of said target surface (3'); an anode (2) having an electron receiving surface (2', 2'', 2''') surrounding at least one of the target (3) and the confinement portion (4) in at least one of a target plane and an axial distance in front of an active surface; a magnetic guidance system configured to provide a magnetic field at a target surface parallel to at least an outer region of said target surface such that magnetic field lines are parallel to said target surface or inclined thereto at an acute angle α, said active surface (3'') being defined in a region of said target surface (3') such that said magnetic field lines enter said target surface at an acute angle α≦45°; a central axis Z or a central plane Z′; Both the confinement (4) and the anode (2) are formed in a closed geometry and both are electrically insulated from each other and from the target, and the minimum distance of the electron receiving surface (2', 2'', 2''') from the active surface (3'') is the radial distance Δr of the outer boundary of the target surface (3') to the inner boundary of the electron receiving surface. １４ an outer boundary of the target surface (3') has a radial distance r1 from the middle of the target, and an inner boundary of the electron receiving surface has a radial distance r4 from the middle of the target; １４ and at least one of an axial distance h1 from the target surface (3') to an upper boundary of the containment section and an axial distance h2 from the target surface (3') to a lower boundary of the electron receiving surface (2', 2'', 2''').

10. a target (3) having a target surface (3') with an active surface (3'') from which material can be evaporated in a cathodic arc process; a containment portion (4) surrounding the outer boundary of said target surface (3'); an anode (2) having an electron receiving surface (2', 2'', 2''') surrounding at least one of the target (3) and the confinement portion (4) in at least one of a target plane and an axial distance in front of an active surface; a magnetic guidance system configured to provide a magnetic field at a target surface parallel to at least an outer region of said target surface such that magnetic field lines are parallel to said target surface or inclined thereto at an acute angle α, said active surface (3'') being defined in a surface (3') region such that said magnetic field lines enter said target surface at an acute angle α≦45°; a central axis Z or a central plane Z′; A cathodic arc evaporation apparatus comprising: Both the confinement (4) and the anode (2) are formed in a closed geometry and both are electrically insulated from each other and from the target, and the minimum distance of the electron receiving surface (2', 2'', 2''') from the active surface (3'') is the radial distance Δr of the outer boundary of the target surface (3') to the inner boundary of the electron receiving surface. １４ an outer boundary of the target surface (3') has a radial distance r1 from the middle of the target, and an inner boundary of the electron receiving surface has a radial distance r4 from the middle of the target; １４ and at least one of an axial distance h1 from the target surface (3') to an upper boundary of the containment section and an axial distance h2 from the target surface (3') to a lower boundary of the electron receiving surface (2', 2'', 2''').

11. 11. The device according to claim 1, 2, 9 or 10, characterized in that the parallel magnetic field extends from the target surface (3') to at least an axial distance (h1, h2) of the confinement or the electron receiving surface and / or extends at least to a height of 5 to 20 mm above the target surface.

12. In region A on the target active surface, magnetic flux density B Ａ The device according to any one of claims 1, 2, and 9 to 11, characterized in that the intensity is set to 20 to 500 gauss or more.

13. 13. The device according to any one of claims 1, 2, 9 to 12, characterized in that the containment portion is made of a magnetic or non-magnetic material.

14. Radial distance Δr １４ The device according to any one of claims 1, 2, 9 to 13, characterized in that the distance is 5 to 30 mm.

15. 15. The device according to any one of claims 1, 2, 9 to 14, characterized in that the radial distance r1 from the centre of the device to the outer boundary of the target surface is between 40 and 110 mm.

16. 16. Device according to any one of claims 1, 2, 9 to 15, characterized in that the radial distance (h1, h2) is between 0 and 20 mm.

17. The device according to any one of claims 1, 2, and 9 to 16, characterized in that the maximum axial distance h3 of the electron receiving surface is 10≦h3≦50.

18. 18. The apparatus of any one of claims 1, 2, 9 to 17, wherein the magnetic guiding system comprises at least a central magnet having a pole located in front of the center of the rear face of the target and axially aligned with said pole, and a circumferential ring magnet having a reciprocal pole in or below the plane of the target, the circumferential ring magnet surrounding the central magnet and at least a portion of the target.

19. 20. The apparatus of claim 18, wherein at least one of the central magnet and the peripheral ring magnet is an electromagnet or a permanent magnet.

20. 20. The apparatus of claim 18 or 19, wherein the magnetic axis of the circumferential ring magnet is tilted upwardly away from the central axis Z or plane Z'.

21. 21. Apparatus according to any one of claims 18 to 20, characterized in that the circumferential ring magnet comprises two electromagnetic coils C2 and C3, the diameter of C3 being larger than the diameter of C2.

22. 22. The apparatus of claim 18, wherein the magnetic guiding system further comprises a circumferential yoke surrounding the circumferential ring magnet, the target and the anode, the circumferential yoke being made of a magnetizable material.

23. The magnetic guiding system further comprises a central limiter disposed in or around the center of the target surface, the central limiter being electrically insulated with respect to the target and having a Curie temperature T Ｃ 23. Device according to any one of claims 18 to 22, characterized in that it is made of a magnetic material having a temperature > 500°C.

24. 24. The device of claim 23, wherein the central limiter protrudes from 0 to 20 mm above the target surface or relative to the axial distance h1 or h2.

25. 24. The apparatus of claim 23, wherein the central limiter is coplanar with the target surface.

26. 26. The device according to any one of claims 23 to 25, wherein the containment portion is made of a non-magnetic material.

27. The minimum distance from the target active surface (3') to the electron receiving surface (2', 2'', 2''') is a radial distance Δr １４ and an axial distance h1 or h2.

28. A vacuum chamber equipped with the device according to any one of claims 1, 2, and 9 to 27.

29. 28. A method for depositing a coating on a substrate in a vacuum chamber using an apparatus according to any one of claims 1, 2, 9 to 27, wherein an electron trap is established at least directly above the target surface (3) in a region A by applying an essentially parallel magnetic field with magnetic field lines entering the target surface at an acute angle α≦45° to at least an outer region of said target surface (3) using a magnetic guiding system, thereby forming an active surface (3″), and a cathodic arc discharge is ignited and maintained on the active surface, said region A being laterally bounded by a confinement at a floating potential.

30. 30. The method of claim 29, wherein region B is formed on region A up to an axial distance h3 from the target surface given by the maximum axial distance of the electron receiving surface.

31. 31. The method of claim 29 or 30, wherein region C is formed above region A and region B, the magnetic field is very low or zero, and the atmosphere contains reactive gas molecules and further contains at least one of positively ionized metal ions and positively ionized reactive metal ions.

32. 32. The method according to any one of claims 29 to 31, wherein the cathodic arc discharge is maintained at a discharge voltage between 20V and 50V.

33. 33. The method according to any one of claims 29 to 32, characterized in that the coating is an AlMeN, AlMeO or AlMeNO compound, where Me represents one or more metals of the transition metals of group IV, V or VI.

34. A method for producing a substrate coated by the method of any one of claims 29 to 33.

35. 35. The method of claim 34, wherein the substrate is a tool or part.

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