Magnetron sputtering source, sputter coating system and method for coating a substrate

Technical field

The invention relates to a magnetron sputtering source for a coating installation, comprising at least one cathode and at least one cathode associated with or providing in the cathode integrated target that coating and / or treatment material for coating and / or for the treatment, means for generating a coating plasma, at least one magnet arrangement for generating a magnetic field for influencing the coating plasma such that at least over a partial area of ​​the target, at least one plasma channel is produced, wherein the magnet arrangement and the target, preferably by means of at least one actuator, relative to each other are arranged to be movable. In addition, the invention relates to a sputter coating system comprising at least one treatment or coating chamber and a magnetron sputter source. The invention also relates to a method for treating, in particular for coating a substrate comprising the steps of:<ol><li>a) providing a treatment or coating line with a target;</li><li>b) generating a coating plasma;</li><li>c) generating a magnetic field for influencing the coating plasma such that at least over a partial area of ​​the target, at least one plasma channel is produced; and</li><li>d) generating a relative motion between the magnetic field and the target.</li></ol>

State of the art

For the coating of substrates or substrate surfaces, in particular for coating or treating large-area substrates, different methods are known. The coating processes used must be capable of generating even thin layers with high homogeneity and uniformity. Moreover, it is in the sense of an economical operation of coating equipment necessary to reduce the size of the plant and to achieve a high throughput of substrates so that layer systems can be offered at reasonable prices. Under these conditions, great efforts are made in order to realize high quality coating systems for large area substrates, by using efficient coating methods.

Or sputtering (cathode) atomization is a common technology used for producing thin films on substrates. In sputtering method with a target ion, for example, with inert gas ions is from an inflamed plasma bombed. Thereby, the material which is used directly or indirectly for coating, sputtered from the target, that is released or atomized. The sputtered material is deposited under certain circumstances by a chemical reaction on the substrate opposite the target. The substrate may be arranged to the target during the coating process either stationary relative, or continuously transported past the target.

To increase the efficiency of the sputtering process, so-called. Magnetron sputter sources can be used. A magnetron sputter source has a magnet arrangement that is arranged on the side facing away from the substrate of the target. The magnet system generates a magnetic field and affects the coating plasma, which substrate side is formed in an area above the target surface. Depending on the course of the magnetic field lines is formed over the surface of the target an inhomogeneous structure of the plasma, which leads to non-uniform erosion of the target material. Typically, magnetic devices are used which generate plasma channels in a closed form, for example in the form of an elongated oval (race track). The inhomogeneity of the plasma results in the formation of erosion trenches in the target. This allows for a target material can not be fully used, on the other hand cause the inhomogeneous removal and the formation of erosion trenches to a non-homogeneous and uniform coating of the substrate.

To counteract this, mobile magnet arrangements have been proposed which change the plasma distribution over the target surface in time such that a substantially homogeneous erosion of the target material can be achieved. For example, oscillating movement of the magnetic field are generated in order to smooth the erosion trenches.

In addition to the requirement for high homogeneity of the coating and complete as possible utilization of the target material is the requirement for high efficiency of coating systems. The efficiency of known sputtering systems is substantially limited by an adjusting to high surface temperature of the target in the area below the plasma channels. In an attempt to increase the sputtering rate and thus the sputtering power, the energy input per unit area increases. This results in surface effects, which have unwanted interference sputtering result. The surface effects can exist in the target material eg. As in a melting of the target, in a local outgassing of the target and in chemical transformations of compounds. The consequence of these effects are melted targets and thermally conditioned arcing (arc discharge). The most obvious measure to prevent the temperature mentioned effects is in a cooling of the target. The target may be fixed in accordance with, for example on a cooled backplate.

However, a cooling device to reduce only limits the temperature of the uppermost atomic layers of the target. For example, the maximum power density for sputtering of ITO by the occurrence of arcing at higher power densities than about 3 W / cm² limited.

Technical Problem

Assuming it is the object of the present invention to provide a magnetron sputtering, a sputter coating plant and a method for treating a substrate to provide, by means of which the efficiency of the coating process can be increased by increasing the power density.

Technical solution

This object is achieved by magnetron sputtering sources according to claims 1 to 3, a sputter coating apparatus according to claim 17 and a method according to claim 18th

Accordingly, the inventive magnetron sputtering source for a coating installation, at least one cathode and at least one cathode associated or ausgebildtes as a cathode target which coating and / or treatment material for coating and / or treatment provides means for generating a coating plasma and at least one magnet arrangement for generating a magnetic field for influencing the coating plasma such that at least over a partial area of ​​the target, at least one plasma channel is produced. The magnet assembly and the surface of the target are relative to each other movably arranged so that the plasma channel over the surface of the target can be moved. The magnetron sputtering source is set such that for reducing the heat load on the target surface, the exposure duration of the plasma is reduced to the surface area by increasing the relative velocity between the magnet arrangement and the target.

The exposure time is calculated as the quotient of the width of the plasma channel (the width in this regard is the extent of the plasma channel along the direction of movement), which sweeps over the surface area, and the scan speed. The smaller the area of ​​the plasma channel and the greater the relative speed, the lower the duration of action of the plasma channel is to a certain area of ​​the target surface. For this reason, a combination of small plasma channel section and a high scanning speed (for example, greater than 0.1 m / s) ensures a short duration of action on the surface area. The sputtering rate can be adapted to the exposure time, in particular increased so far that despite high sputtering rate (still) no undesirable surface effects. In addition, the area ratio between total target surface and the plasma channel must be so high that before the next scanning this mentioned surface area takes place a sufficient cooling of the surface. The period of action of the plasma relates to a one-time movement of the plasma channel across the surface area of ​​the target. The larger is the area ratio between the entire target surface and the surface of the plasma channel and the plasma channels, the greater, for a given velocity profile along the path of the plasma channel (and at a complete scanning of the surface), the "recovery time" for the surface areas of the target between two consecutive scans / plasma effects.

The object is also achieved comprising at least one cathode and at least one cathode associated target that coating and / or treatment material for coating and / or treatment provides by a magnetron sputtering source for a coating installation, means for generating a coating plasma and at least one magnet arrangement for generating a magnetic field for influencing the coating plasma such that at least over a partial area of ​​the target, at least one plasma channel is produced. The magnet assembly and the surface of the target are arranged movable relative to each other by means of a drive. The drive is set such that during a coating cycle, a velocity of the relative motion of at least 0.1 m / s is exceeded.

The object is also achieved by a magnetron sputtering source for a coating installation comprising at least one cathode and at least one cathode associated target that coating and / or treatment material for coating and / or treatment provides means for generating a coating plasma and at least one magnet arrangement for generating a magnetic field for influencing the coating plasma such that at least over a partial area of ​​the target, at least one plasma channel is produced. The magnet assembly and the surface of the target are arranged movable relative to each other. The magnetron sputtering source is set such that the power density at least intermittently a value of at least 5 W / cm² achieved, the relative velocity between the magnet arrangement and the target function of the power density (and thus the sputtering rate) is so high that no unwanted temperature induced surface effects on the target surface occur.

The present invention is based on the recognition that the thermal inertia of the surface of the target can be utilized to operate at higher power densities and consequently higher sputtering rates. The power density corresponds to the cathode per unit of area introduced into the system performance. The power density depends functionally together with the sputtering rate.

By the use of higher relative velocities than 0.1 m / s acts on the plasma has a surface area of ​​the target during a movement of the plasma channel significantly shortened relative across the surface area of ​​time. The shorter period of time of exposure to the plasma at an "overscan" the surface area to power densities or sputtering rates can move up without substantial undesirable surface effects on the target surface, such. As arcing, melting of the target, local outgassing of the target, chemical reactions of compounds in the target, etc., occur. This means that a total of the energy input in a surface area (with a certain unit area) over a predetermined (short) period can be increased without surface effects take place at the target surface. Optionally, during a coating cycle, the target repeatedly be "scanned" by the plasma channel, the temperature of the uppermost atomic layers of the target increases significantly less than that of a longer, although less powerful action of the plasma.

From an action of the plasma on the target surface then are to be addressed in the present application, when ions produced in the plasma incident on a surface area of ​​the target surface, interact with the surface in this area, and sputtering coating material from this area. It goes without saying that the surface is heated at a longer-term action, so that it can lead to the undesirable surface effects already mentioned. For this reason, the speed is increased according to the invention as the scanning of the surface, even at an increased power density by means of the specific heat capacity, the thermal inertia of the target is utilized.

If a surface area during a coating cycle is repeatedly scanned, is preferably taken to ensure that the period between the two exposure phases is sufficiently large for a cooling of the surface. The heating during scanning depends on the total energy supplied to and from the sequence in which the energy is supplied from. It has been recognized that meaningful sequences of the power supply are possible as a practically constant supply of energy with low sputtering rate. The velocity profile is adapted to the length of stay of the plasma above the target.

The relative movement between the magnet arrangement and the surface of the target is to be construed broadly within the scope of the invention. Here, the target or the cathode may move relative to the magnet assembly. Alternatively, may be relative to the target and the cathode respectively movable magnet assembly. However, it is also conceivable that both components, magnet assembly and the cathode or target, relative to each other and are positioned relative to the coating apparatus is movable.

The magnet system is arranged on the substrate to be coated facing away from the side to be sputtered targets. In particular, the magnet assembly comprises one or more magnets, in particular permanent magnets, and at least one yoke.

The magnet system may generate one or more plasma channels which are arranged next to one another or reciprocally. As forms of such plasma channels Race tracks (a substantially elongated, oval, closed path), a bone-shaped, closed path or a closed path come like a diamond in question. By selection of a suitable trajectory for scanning, and taking into account dependent on the location coordinates relative speed of the plasma channel during a coating cycle, the distribution layer and the erosion profile of the target can be optimized. In addition, it can be ensured by an appropriate setting of the parameters, such as speed, sputtering, trajectory, etc. a homogeneous coating of the substrate.

Since the invention is suitable for all common sputtering processes, for example sputtering with noble gas (argon, etc.), sputtering with reactive gas (oxygen, nitrogen, NH₃, Etc.) can be used a wide variety of target materials. This can, for example, metals, metal alloys, and metal-nonmetal compounds, such as ITO, IZO, ZnO: Al, SiO₂, IGZO (InGaZnO) be.

The thickness of the target can be increased relative to the thickness of the material over the rest of the target surface at the two points of reversal or reversal sections of the movement of the magnet system, as in the reversal regions on the basis of the speed profile inherently stronger erosion occurs. This measure makes it possible, at the end of target life to obtain throughout the entire target a minimum and uniform target remaining thickness, with the advantage of correspondingly high target utilization. In addition, the vertical distance of the magnet system of the target backing side can be increased in the reversal regions and / or the power supply can be reduced in the reversal regions to prevent a more rapid erosion in these areas compared to the remaining surface areas. Moreover, better coating results are achieved when the reversing area in the edge area of ​​the target is because higher yields are desired in this area for a uniform coating.

A surface region of the target according to the claims is compared to the total area, which is subjected to the plasma channel during the Abscannens, smaller surface area of ​​the surface of the target, in particular covered by the plasma channel part surface of the target. In the limiting case, the surface area can be an infinitesimal small area, is determined via the in any case, the influence or effect of the moving over the range of time the plasma.

The advantages of magnetron sputter source according to the invention are primarily in the possibility of using higher sputtering rates. The higher sputter a coating system can be shortened at a constant cycle time, resulting in a reduction in the total cost of ownership. Moreover, it has been found that with the inventive concept extensive coatings to be deposited static (such. As TFT-coatings), can be realized with much more homogeneous layer thickness distributions than with conventional technologies that use a plurality of parallel cathode.

In a particular embodiment of the invention, the drive is adjusted such that during a coating cycle, a velocity of the relative motion of at least 0.1 m / s, especially of 0.2 m / s, especially of 0.3 m / s, in particular from 0 , 5 m / s, especially of 1.0 m / s, especially of 3.0 m / s, especially of 5.0 m / s, is exceeded. By means of suitable drives, such as belt drives or linear motors, also referred to high speeds can be realized readily.

It shows that even at speeds of 0.2 m / s, for example, performance increases with power densities of hitherto 3 W / cm² at power densities of more than 40 W / cm²At speeds of 0.4 m / s performance gains on power densities exceeding 50 W / cm², At speeds of 1.6 m / s, for example, performance increases to power densities of over 55 W / cm²And at speeds of 3.5 m / s at power densities of more than 70 W / cm² possible are. This surprising effect is particularly in increasing rates of usual areas such., 1.5 mm / s 0.1 m / s already strong.

Each surface area of ​​the target surface during the over-scanning is for a certain period of time under the action of the coating plasma, wherein the time duration is inversely proportional to the relative moving speed between the plasma channel and the target surface. This means that a shortening of the exposure time of the plasma is achieved at the surface area by increasing the speed. This makes it possible in turn to use higher sputtering rates during scanning.

The magnet system can for producing the relative movement, for example, oscillate between the two parallel, in particular between the two shorter target edges. This oscillation can be obtained by movements in other spatial directions (not parallel to the central longitudinal axis of the target ie) are superimposed. The instantaneous speed can be relatively over most of the trajectory to the target surface constant. This constant speed to achieve the mentioned in the claims minimum speed values ​​at least. Alternatively, the instantaneous velocity also be variable to adjust z. B. layer thickness distributions or target erosion profiles. It is clear that the presence of inflection points and decelerations of the relative movement speed temporarily drops to lower values ​​or to zero. In the present invention, however, the scanning speed is over a major part of the web run over the target surface, preferably over 50% of the path length, more preferably over 75% of the length of web, during a coating cycle exceed those mentioned in the claims speed values. Depending on the target length of the Scanned data at high speed range is even greater.

At high Oszillationsgeschwindigkeiten or large masses of the magnet system vibrations can result in a coating plant. These vibrations can be counteracted by counterweights.

In particular, the magnetron sputtering source is set such that the power density at least intermittently a value of at least 5 W / cm², In particular a value of at least 15 W / cm², In particular a value of 30 W / cm², In particular a value of 50 W / cm², In particular a value of 75 W / cm², reached. The load on the surface of the target by increasing the sputtering rate is by increasing the scan (scanning) speed, and thus the duration of exposure of the plasma to the compensated area. The inventive magnetron sputtering source is formed or adjusted for operation with such power densities.

In a particular embodiment, the adjustment of the relative velocity between the magnet arrangement and the surface of the target from the ratio of the size of the overall surface of the target to the image projected onto the target surface area of ​​the plasma channel or to the area on the surface of the target, which is subjected to the plasma appreciably and depending on the desired sputtering rate. This means nothing else than that the speed is chosen such that at a predetermined high sputtering and a predetermined effective area of ​​the plasma channel unwanted surface effects are avoided. the speed is maximum adjusted so that an associated maximum sputtering rate, which is determined empirically, can be realized from a different perspective.

In particular, the ratio of the total surface of the target to the surface of the plasma channel at least 15, in particular 30, especially 45, in particular 90. The said area ratio is in connection with the other successive tunable variables, namely the velocity profile and the profile of the sputtering rate (via path) , is also important. This ratio determines the frequency at which a certain area of ​​the target surface is under the influence of the plasma. When using one or even several plasma channels the ratio of total sputtering surface of the target to the surface of the plasma channel or the plasma channels must be large enough that any surface area to cool sufficiently before the next scan. Since the largest possible area ratio ensures good cooling, the process particularly suitable for large area deposition is suitable with large targets. Moreover, in a large area ratio, a sufficiently high speed, combined with high sputtering rates can be realized. The result is that the area ratio determined indirectly via the adjustable rate, the maximum possible sputtering.

Such large area ratios are otherwise only in connection with an increase in power density (and according to the sputtering rate) and speed economic sense. This results in short cycle times are achieved at the coating of a substrate, despite the large area ratio.

The sputtering is preferably set such that the entire exposure time of the plasma is divided to a specific surface area of ​​the target per coating cycle into at least two temporally separated time periods.

As a coating cycle, a cycle of coating a substrate is considered that performed in the station intended coating. As the coating cycle, however, can also be a closed time coating process are considered, in which a plurality of substrates are sequentially coated directly.

The statement is that any surface area of ​​the target for this is due to the high scanning speed and short two or more times during a coating cycle under the action of the plasma. In this way, the thermal inertia of the target material is used, which is not overly warm during the short scan time and an appropriate area ratio (as described above) to cool sufficiently between two scan cycles.

The target is preferably rectangular with a length and a width, preferably the length is a multiple of the width, and the magnet arrangement and the target along at least the direction of the length of the target are arranged relative to each other movable. This movement can be superimposed by movements in other spatial directions. In particular, can be performed between the two transverse edges, an oscillating relative movement.

The target may be formed with a substantially flat and / or curved surface. The target may be mounted on a cooled backplate, for example by bonding, brackets, screws, spraying, etc. The target may either Planarkathode or domed cathode, for example, be of a size of 2.5 mx 0.3 m, formed. The target may also be a surface cathode or curved surface cathode, for example having a size of 2, 5 mx 2 m, formed. By using the arched cathode layer distribution can be controlled on the substrate or a homogeneous, uniform layer distribution can be achieved on a curved substrate in certain cases.

In the magnetron sputtering source can be around a rotatable magnetron tube sputtering source with a pipe-cathode and / or a rotatable tubular target, however, also. The relative velocity between the target and the magnet system here corresponds to the web speed of the target surface relative to the magnetic system. The area ratio between the total surface of the target and the surface of the plasma channel can be achieved inter alia by increasing the target diameter. The principle of the invention is to be where the description area targets specified, refer to all sorts of rotatable cathodes / targets.

Preferably, at least one anode or anode arrangement is provided for receiving derivable electrons. The anode can be formed by the surroundings of the magnetron cathode, for example the chamber wall, a dark room frame, a peripheral profile, etc.

However, the anode or anode arrangement may in particular also comprise at least one electrode which is arranged relative to the target on the target surface movable. The electrode will move in this case generally in sync with the magnet system relative to the target. For example, can be arranged, the electrode along a plasma channel.

The anode or anode arrangement may comprise a plurality of electrodes which are disposed relatively above the target surface to the target immovable or fixed. So can be used as anodes or a plurality of cooled or uncooled rods, which are located along the direction of movement of the magnet system before the target or the target edge and / or parallel to the magnet system in front of the target. The electrodes act selectively into the plasma channel and are synchronously switched electrically to the movement of the magnet system.

The target may preferably consist of one or more segments, which are galvanically coupled or separated. If the target is divided into segments of mutually decoupled, means may be provided, which a segment as a cathode at least switch, while at least one adjacent segment is switched as anode. The electric potential of the individual target segments can be synchronized with the movement of the magnet system, that is, the target segments may be synchronously further electrically connected with the movement of the magnet system. The negative Sputterpotential is for example only on that target segment that runs beneath it at the appropriate time by the magnet system. The remaining target segments are not on Sputterpotential, but for example to ground, on a positive or a floating potential. By using the anodes or anode assemblies may arcing and unwanted secondary plasmas, such as. For example, arc discharge can be avoided.

The means for generating a coating plasma may comprise a device for power supply, comprising an AC (alternating current), a DC (direct current), a unipolar pulsed, a bipolar pulsed or an RF (radio frequency) source. Of this source of the power is coupled into the system.

The inventive object is also achieved, including at least one treatment or coating chamber, and a magnetron sputter source described by a sputter coating system as described above.

The object is further achieved by a method for treating a substrate, particularly for coating a substrate comprising the steps of:<ol><li>a) providing a treatment or coating line with a target, especially a treatment or coating installation as indicated above;</li><li>b) generation of a coating plasma on the substrate side over at least a partial area of ​​the target surface;</li><li>c) generating a magnetic field for influencing the coating plasma such that at least over part of the surface of the target, at least one plasma channel is produced; and</li><li>d) generating a relative movement between the magnetic field and the target.</li></ol>

To reduce the heat load on the target surface, the exposure duration of the plasm is as reduced to the surface area by increasing the relative velocity between the magnet arrangement and the target.

Moreover, the object is achieved by a method for treating a substrate, particularly for coating a substrate comprising the steps of:<ol><li>a) providing a treatment or coating line with a target, especially a treatment or coating installation as indicated above;</li><li>b) generation of a coating plasma on the substrate side over at least a partial area of ​​the target surface;</li><li>c) generating a magnetic field for influencing the coating plasma such that at least over part of the surface of the target, at least one plasma channel is produced; and</li><li>d) generating a relative movement between the magnetic field and the target.</li></ol>

The relative speed between the magnetic field and the target exceeds a value of at least 0.1 m / s.

The plasma channel is performed at high speed (relative) over a surface area of ​​the target of time, so that a time period in which the plasma is applied continuously to the surface portion, is shortened so that, even at high power density (and thus higher sputtering rate) no significant adverse surface effects on the target surface occur.

In particular, the relative velocity of the plasma channel with respect to the surface of the target exceeds a value of 0.1 m / s, especially of 0.2 m / s, especially of 0.3 m / s, especially of 0.5 m / s, in particular of 1.0 m / s, especially of 3.0 m / s, especially of 5.0 m / s.

In particular, the plasma channel has an oval, an elongated oval, a bone-shaped or diamond-shaped shape.

During the relative movement between the magnetic field and the surface of the target, preferably, the power density reaches at least intermittently a value of at least 5 W / cm², In particular a value of at least 15 W / cm², In particular a value of 30 W / cm², In particular a value of 50 W / cm², In particular a value of 75 W / cm², The inventive magnetron sputtering source is formed or adjusted for operation with such power densities.

The magnetic field influences the plasma for forming at least one plasma channel in particular in an oval shape (race track), a bone-like shape and / or in the form of a rhombus.

In the method referred to a ratio of the entire sputtering surface of the target to the image projected onto the surface of the target area of ​​the plasma channel exceeds a value of 15, in particular 30, especially from 45, especially 90. Assigns in step c) generated plasma channel a relative to the surface of the target small area, so are the time intervals, between which a surface area of ​​the target surface is scanned, relatively large.

In particular, the target is rectangular with a length and a width, the length being a multiple of the width, and the magnetic field at least along the direction of the length of the target moves relative to the target. In particular, the magnetic field can oscillate relative to the edges of the target.

The total exposure time of the plasma to a specific surface area of ​​the target surface can be divided per coating cycle in at least two chronologically separate periods.

All of the features described are claimed both in connection with the apparatus and the method, as well as individually and in any combinations.

Brief description of the figures in the drawings

Further features and advantages of the invention will become apparent from the following description of preferred embodiments and with reference to FIGS. Show it:

<figref idrefs="f0001">figure 1</figref> A sectional view of a coating system according to the invention;

<figref idrefs="f0002">figure 2</figref> A side view of a coating system according to the invention;

<figref idrefs="f0003">figure 3</figref> A sectional view of a magnetron sputter source according to the invention;

<figref idrefs="f0004">figure 4</figref> A top view of a section of a sputtering source according to the invention during operation;

<figref idrefs="f0005">figure 5</figref> A side view of a section of a sputtering source according to the invention during operation

<figref idrefs="f0006">figure 6</figref> A side view of a portion of another sputtering according to the invention during operation;

<figref idrefs="f0007">figure 7</figref> A top view of a sputtering source according to the invention;

<figref idrefs="f0007">figure 8</figref> A rotatable cathode in the context of the invention; and

<figref idrefs="f0008">figure 9</figref> A diagram outlining the relationship between the set speed and the power density.

WAY (S) OF IMPLEMENTING THE INVENTION

The <figref idrefs="f0001">figure 1</figref> shows a coating system 1 of the invention in a sectional view. Within a coating chamber 2 is a elongated configuration cathode 3 with a length I and a width b is arranged on which a target 4 is mounted. The cathode 3 is in this view below the target 4 in the leaf level. However, the cathode 3 and target 4 may be formed in the framework of the invention as an integrated component, that is the target material 4 itself may form the cathode of the third

The cathode 3 is connected via a connecting cable to the power supply. 5 The electric power can be coupled into the coating system 1 as DC, AC, pulsed power non-polar, bipolar pulsed power or RF (radio frequency) voltage.

The <figref idrefs="f0002">figure 2</figref> shows how the coordinate system indicates the top left, a lateral section of the coating machine 1. Inside a coating chamber 2, which is bounded by walls, a cathode 3 and attached to the cathode 3 target material 4 are arranged. The target material 4 is a substrate layer 6, in which the substrates are or along which the substrates are transported, facing during coating.

The substrate plane 6 opposite extends substantially parallel the target 4 with the underlying cathode 3. In this context it should be noted that the target itself may form the cathode. The target 4 must be at cathode potential in any case always.

Verso of the cathode arrangement 3 moves, as indicated by the arrow v, a magnet system 7 (for example, consisting of yoke and magnet, not shown in detail) along the longitudinal direction of the cathode 3 and the target 4 at a high speed, for example, 1 m / s , The target 4 is abgescant high relative velocity v along the length I of the target 4th The magnetic system may be mounted on a carrier of a drive (not shown) are driven.

The magnet system 7 is designed such that it generates a rotating oval plasma channel 8 (Race track) at a distance above the target surface. The plasma channel moves over the surface of the target 4 at the same speed v as the magnet system 7. The direction of movement is indicated by the arrow v. Due to the high scanning speed is prevented from locally such a strong heating of the surface 4 'of the target 4 occurs, which can lead to surface effects such as melting of the target 4, local outgassing or chemical conversions of the compounds in the target 4th In addition, a arcing (temperature-induced arc discharge) is prevented.

An inventive magnetron sputtering source is in the <figref idrefs="f0003">figure 3</figref> shown.

The surface 4 'of the target 4 to the substrate has to level 6, the magnet system 7 is remote from the substrate plane. The target 4 may be cooled under certain circumstances.

The magnet system 7 moves primarily at high speed in a direction perpendicular to the plane (x-direction) relative to the target 4. However, superimposed movements in the y- and z-direction are possible.

A relative movement of the magnet system 7 to the target 4 means that either the magnetic field oscillates, for example in the x direction between the parallel shorter edges target. Alternatively, the target 4 against the magnet system 7 can be driven while the magnet system is firmly positioned in the coating chamber. 2 Also an opposite movement of the magnet system 7 to the target 4 is conceivable. It could, for example, the target 4 to perform a quick movement in the x direction, while the magnet system 7 passes through a superimposed movement in the y and / or z direction.

The <figref idrefs="f0004">figure 4</figref> shows a plan view of a target 4 a sputter source according to the invention.

are below the target 4, indicated by the arrows, arranged in x-direction movable magnets or magnet arrangements. This move at a speed, as illustrated by the arrows v, or a predetermined speed profile along a scan path. It is indicated by the arrow u a superimposed countermovement of the target 4, making a total in the x-direction, a relative velocity u + v results.

The magnets and magnet systems form under appropriate conditions vertically above the target surface 4 'plasma channels 8, 8', 8 "from. These plasma channels 8, 8 ', 8" move together with the magnet systems in the x direction with velocities u + v relative to the target. 4

The plasma channels 8, 8 'and 8 "have examples of different closed configurations, including an elongated oval (racetrack 8) a diamond-like shape 8', which does not extend over the entire width b of the target 4, and a bone-shaped surface 8" (each projected onto the target surface 4 ') on. The areas of the plasma channels 8, 8 'and 8 "are small compared to the entire the scanned target surface 4' (both individually and the sum of the surfaces 8, 8 ', 8").

For example, an area ratio between the area of ​​the target 4 and the and the surfaces of or the plasma ducts 8 and 8 'and 8 "is set much larger than the 5th In this way, high relative speeds can u + v in the x direction between the magnet system 7 and the target 4, for example relative velocities greater than 1 m / s can be realized. It has been shown that due to the high relative velocity u + v, combined with the large area ratio, the temperature in the uppermost atomic layers of the target 4 over conventional arrangements can be significantly reduced. the better cooling enables the other hand, the use of significantly higher power densities or sputtering without interfering surface effects, such as melting of the target or arcing.

In the <figref idrefs="f0004">figure 4</figref> is also exemplified an anode 9 to the plasma channel 8, which extends in the region of the racetracks. The anode 9 moves synchronously with the underlying the cathode magnet system and thus with the plasma channel 8 with an absolute speed v, so with a relative velocities u + v, over the target surface 4 '. Superimposed to the target 4 and / or the magnet system can perform a relative movement in the y and / or z direction, so that a certain erosion profile is selectively adjusted.

Another embodiment of the invention showing the <figref idrefs="f0005">figure 5</figref> in a lateral sectional view.

A cathode 3 is provided with target material 4, wherein the target surface is 4 'aligned to the substrate plane 6 toward.

Below the cathode 3 facing away from the plane of the substrate 6 side is the magnet system 7, which (as indicated on the top left in the figure) is moved at a velocity v along the x-axis. With the magnet system, a variety of other plasma channels also moved at a distance above the surface of the target 4, a plasma channel or race-track 8. Naturally, in addition to the plasma channel 8 by a corresponding configuration of the magnet system 7 is movable in the area above the target surface 4 ' are formed.

The plasma channel 8 extends in projection over a region d along a total area D of the target 4 (D here corresponds to the length l of the target). The area ratio between the entire target surface and the surface of the plasma channel 8 (projected onto the surface of the target 4) in the invention is at least 15. This can especially apply to the D / d ratio. The surface of the plasma channel can be roughly equated with the surface of the yoke, because these quantities are substantially similar dimensions.

By means of the magnet system 7, 6, one or more plasma channels (race-track) are generated 8, which may be arranged in a pattern next to each other or reciprocally in an area above the target 4 between the target 4 and the substrate plane. In particular, the magnet assembly can be 7 formed specifically so that a specific layer distribution and the erosion profile of the target 4 are optimized.

In the <figref idrefs="f0005">figure 5</figref> an immovably arranged relative to the target 4 anode assembly 9 is also shown. The anode assembly 9 may be principally constituted either by the environment of the magnetron cathode 3 (for example, the chamber wall, a dark room frame, a peripheral profile, etc.). In the<figref idrefs="f0005">figure 5</figref> Illustrated case, the anode assembly 9 of a plurality of adjacent bars, which can be cooled or uncooled. These act selectively in the plasma duct 8 and are further electrically connected with the movement of the magnet system. 7 Alternatively could one or two electrodes 9 can be provided, which move together with the magnet system 7 and are arranged along a plasma channel.

A drive 10 for the magnet system 7 may be provided by a control device 11 for controlling the scanning speed and / or the scanning path and / or the power density (and hence the sputtering rate). The controller 11 can control the sputtering rate, for example in dependence on the speed and / or the spatial coordinates of the magnet system. Due to the high over the major part of the scan path set speeds can power densities well above 3 W / cm², For example, power densities of 10 W / cm², 50 W / cm² or even 75 W / cm² be exceeded.

The <figref idrefs="f0006">figure 6</figref> shows a further embodiment of the invention, like elements being designated by the reference numerals used previously are designated.

In this embodiment, the cathode 3 and the target 4 are segmented. The or the corresponding target segments in the area of ​​the plasma channel 8 are at cathode potential while the adjacent corresponding target segments act as an anode. The segments are further connected in this embodiment along with the movement of the magnet system 7 and the plasma channel 8, corresponding with a speed v.

The distance between segments preferably corresponds to the dark-space distance to avoid electrical arcing between adjacent segments which lie on a different potential. The hint of proportions at the<figref idrefs="f0006">figure 6</figref> is purely schematic.

By pointing in the z-direction arrows on the magnet system 7 is to be clear that the magnet system 7 the direction of movement in the x direction superimposed can movements, for example in the z, but also in the y direction, perform.

Overall, the invention for a number of common sputtering processes can be used, for example, sputtering with noble gas (argon, etc.), but also for sputtering processes with reactive gases (oxygen, nitrogen, NH₃, Etc.).

In the <figref idrefs="f0007">figure 7</figref> is another sputtering invention discloses that differs from the previous exemplary embodiments of an anode assembly that are arranged parallel to the direction of movement v of the magnet system 7 and the plasma channel. 8

The <figref idrefs="f0007">figure 8</figref> shows a rotatable cathode in the invention. The increased relative speed is marked as web speed v on the surface of the target. The Scanned data target length corresponds to the circumference here. Cathode / target 3, 4 to rotate around a central axis A. The Race track 8 via the magnet system 7 is indicated in dashed lines.

The <figref idrefs="f0008">figure 9</figref> shows a diagram (in two versions, without and with measurement points) the dependence between the set speed and the maximum possible power density, ie, the power density that can be supplied before the target surface anschmelzt before arcing occurs or before chemical changes within the target surface occur, illustrates. A sharp rise of the possible supplied power density can be seen / s already at speeds of 0.1 m. The curve rises at higher relative speeds continues to rise, but with a lower pitch (starting between about 0.3 m / s and 0.4 m / s). Nevertheless, an increase in the speed still results in the higher speed ranges in significant increases in power density.

The unexpectedly high power densities were not achieved at usual speeds in mm / s range and could not be expected.