KR20050053605A - Magnetron sputtering source - Google Patents

Abstract

Disclosed is a magnetron sputtering source, comprising at least two long targets (3a, 3b, 3c) which are electrically insulated from each other and arranged next to each other in a longitudinal direction. The lateral spacing is substantially smaller than the corresponding spreading of the targets (3a, 3b, 3c). Each target has its own electrical connection (5a, 5b, 5c). Anodes (7a, 7b) are provided preferably between the targets (3a, 3b, 3c).

Description

Magnetron sputtering source

The present invention relates to a magnetron sputtering source, a vacuum chamber with the source, a vacuum coating system with the chamber, and a method of operating and using the system. .

The present invention provides a coating of a film having a uniform film thickness distribution on a large-surface, particularly rectangular substrate, having an area of at least 900 cm ² by sputter coating, in particular reactive sputter coating. It is based on the need to do so. Such substrates are used, in particular, to produce flat panels for TFT panels or plasma display panels (PDPs) on thin glass substrates of usually 1 mm or less in thickness.

When coating large areas with magnetron sputters, it is common to have a much larger area of sputter surface and consequently a larger area target if the sputtering source and the substrate do not move relative to each other. However, this leads to problems related to:

(a) uniformity of process conditions on a large area target, in particular severity in reactive sputter coating,

(b) erosion profile

(c) cooling

(d) strain on large area targets by atmospheric pressure and refrigerant pressure;

In order to solve the mechanical load problem (d), a relatively thick target plate must be used, which reduces the magnetic penetration and consequently the effect of electron traps on a given input power. If the power is increased, a cooling problem (c) arises, which is not only because of the sophisticated methods required to ensure good contact between the target and the refrigerant, but also because of the obstruction of the equipment behind the magnets. do. In addition, in magnetron sputtering, whether it is reactive or non-reactive, the target device is generally composed of a target plate that defines a sputtering area and an associated mounting plate, which is made of the material to be sputtered, and the target is a " Sputter erosion along a "race track". One or more circular erosion furrows on the sputter face due to the tunnel-shaped magnetic field applied to the target along a specific course, creating a circular zone with increased plasma density. Is formed. This phenomenon is caused by the high electron density (electron trap) in the tunnel-shaped circular magnetic field range. Because of this "race track," a non-uniform film thickness distribution already occurs in a relatively small area coated substrate installed in front of the magnetron sputtering source. In addition, the sputter erosion that occurs along the "race track" target material because it hardly sputters the material from the target area outside of such a track, resulting in a wave-shaped or furrow-shaped erosion profile. Is used inefficiently. Because of this "race track", the substantially sputtered area of the large area target is small compared to the substrate area. In order to eliminate the "race track" effect on such coatings, it is possible to move the sputtering source and the substrate to be coated relative to each other as described above, but this slows down the coating speed per hour. In addition, cooling problems arise when locally sputtering power is used in a system using relative motion.

When attempting to achieve the desired purpose, one basically encounters four complex problems (a), (b) and (c), (d), each of which solves the problem associated with the other problems. Worsens. In other words, the problem solving is mutually conflicting.

An object of the present invention is a magnetron, which can be manufactured to substantially any size, which can solve the above problems, and economically achieve a uniform coating thickness distribution on at least one large area substrate stationary relative to a sputtering source. To provide a sputtering source. Not only can the source maintain very uniform process conditions, but it will also be suitable for sensitive reactive processes with high coating rates. In reactive processes, non-uniform "race track" effects result in known serious problems due to high plasma density gradients.

In the magnetron sputtering source according to the invention, at least two, preferably two or more electrically isolated long target arrangements are parallel to one another at a distance much smaller than the width of the target device. And each of the target devices has its own electrical connections, and a cathode device is also provided. The target of the target device preferably has a rounded corner along the "race track" path.

In the magnetron sputtering source of the present invention with power inputs to individual target devices that are independently adjustable, the film thickness distribution that is coated on the underlying substrate can be greatly improved. The source of the invention can be modularly adapted to any substrate size to be coated.

With respect to the overall arrangement, the cathode device may be located outside of the entire device, unless it is temporarily formed by the target device itself, but preferably between the target devices and / or longitudinally in front of the target device. And particularly preferably vertically installed cathodes between the target devices.

It is also desirable to install a stationary magnet arrangement in the source; The stationary magnet device is formed by one magnet frame surrounding all target devices, or by magnet frames surrounding each target device. Although it is possible and reasonable to install a controllable electric magnet in at least a portion of the frame (s), i.e., the stationary magnet device, a permanent magnet is used as the magnet of the stationary magnet device, i.e., the frame. It is desirable to install.

By designing a stationary magnet device, preferably a permanent magnet frame, taking into account the magnetic field that they generate on the immediately adjacent target device, the above-described film thickness distribution and long target on the substrate through the specific shaping of the "race track". Can improve the utilization efficiency.

The magnet devices are preferably provided under each of at least two target devices. They are locally stationary so that they can be fixed for a time to form a tunnel-like magnetic field on each target device. Preferably, the magnet devices are designed to cause a change in the magnetic field pattern over time on the target device. The design and generation of magnetic field patterns on each target device according to the present invention is disclosed in EP-A-0 603 587 or US Pat. No. 5,399,253 of the same application, the disclosure of which is incorporated herein. Two are.

According to FIG. 2 of EP-A-0 603 587, the location of the magnetic field pattern and the region with high plasma density may change as a whole, but preferably it may not change or may change only slightly, whereas FIG. And the position of an apex, which is the point where the plasma density is the highest, changes.

In order to change the location of the vertex or region with high plasma density on the magnet device, an optionally controlled electromagnet (static or mobile) can be provided under each target device, preferably such a magnet device is powered Driven permanent magnet is installed.

As a preferred moving magnet device, at least two vertically arranged magnetic drums, which are powered and provided with a rotating bearing, are installed under the target device, more preferably with FIG. 3 of EP-A-0 603 587. As shown in FIG. 4, permanent magnets are installed for each target.

The magnetic drum is driven in pendulum motion, preferably with amplitude ≤ tau / 4. This technique and its effects are described in detail in EP-0 603 587 and in US Pat. No. 5,399 253, the disclosures of which are hereby incorporated by reference.

In summary, it is desirable to provide at least two permanent magnet drums, which are powered and installed with a rotating bearing, extending along the longitudinal axis of the target device.

In a preferred embodiment, the power supply of the target device; The magnetic field of the stationary magnet device, in particular of the frame; And a magnetic device, preferably a magnetic drum, below the target device, as well as a magnetic drum, as well as a set of influential variables that enable optimization (particularly of uniformity) of the jointly coated film thickness distribution. Do. In addition, high utilization of the target material is achieved. The best advantage is that as the peak of the magnetic field on the target device is shifted, the plasma zone is not displaced in a scanning manner, but the plasma density within the zone is changed through wobbling. Will.

To allow for maximum sputtering power input, the target devices are optimally cooled by installing them on a base, where the majority of the target device surface facing the base is sealed to the base by a foil. Covered by refrigerant channels. Since the refrigerant presses the entire foil surface toward the target device to be cooled, large area heat dissipation is achieved.

The magnetron sputtering source according to the invention is preferably provided with a base made of plastic, which is at least partly an insulating material, on top of which the stationary magnet consists of a negative electrode, if any, and preferably a permanent magnet frame, in addition to the target device. A device, preferably a movable permanent magnet device, in particular a magnet device under the target device consisting of a magnetic drum, and a refrigerant channel are installed. The base is designed and installed to separate the vacuum atmosphere from the external atmosphere. In this way, the target device can be more suitably designed for mechanical loads caused by pressure.

Another optimization for this large area film thickness distribution is by means of a gas inlet tube connected to a gas distribution system, distributed along the longitudinal side of the target device. The gas inlet tube is a process chamber at the top of the source according to the invention in a vacuum processing chamber or system of the invention, with a reactive gas and / or working gas having a specially adjusted distribution. ) Into the

The rectangular target device is spaced at intervals of up to 15%, preferably up to 10%, or more preferably up to 7% of its width.

In a preferred embodiment,

The lateral distance d between individual target devices

1 mm ≤ d ≤ 230 mm,

Preferably, 7 mm ≤ d ≤ 20 mm.

The width B of each target device

Preferably 60 mm ≤ B ≤ 350 mm,

More preferably 80 mm ≤ B ≤ 200 mm,

Length (L) is

Preferably 400 mm ≦ L ≦ 2000 mm.

The length of each target device is at least equal to or much longer than their width. Although the sputtering face of each target device is flat or pre-shaped and preferably arranged on the same face, it compensates for any edge effect on the film thickness distribution if necessary. To this end, it is possible to place the sputtering side of the side closer to the substrate to be coated and possibly inclined than the middle sputtering side.

The electrons in the magnetron plasma rotate along the "race track" in a direction defined by the magnetic and electric fields in the target surface area. The routing or effect of the electron orbit and its effect on the eroded bone on the target surface are specifically optimized by forming a magnetic field along the longitudinal axis of the target device and changing the shape of the magnetic field over time and position. Can be. In the magnet frame, preferably one permanent magnet frame each, this is provided by means of positioning and strength selection of the magnets installed in the frame, and / or underneath each target device a magnet device, preferably a permanent magnet drum. And varying the position relative to the strength of the magnet on the magnet device. Since the electrons move in a circular orbit according to the polarity of the magnetic field, it is especially important that due to the deflection force of the electrons in the narrow side region of the target device, the electrons in the diagonally opposite corners are pushed outwards, depending on their direction of movement. Has been observed. Therefore, in the installed magnet frame, the magnetic field strengths formed by the specular symmetrical frame magnets with respect to the diagonal of the rectangular target are preferably designed to have a locally different shape.

In a preferred embodiment of the source according to the invention, the target device is fixed by a linear bayonet unit and in particular by cooling through a pressurized foil of the type as described above. In this way, the target device can be replaced very easily after reducing the pressure in the refrigerant channel; A wider area of the backside of the target device can be cooled and no fixture to secure the target device is exposed towards the processing chamber.

Preferred sources according to the invention are equipped with two or more, preferably five or more target devices.

By using the magnetron sputtering source according to the invention in a sputter coating chamber having a substrate support for at least one preferably sputter coated substrate, the sputtering face (F _Q ) of the source with respect to the substrate surface F _S to be sputtered It is possible to optimally reduce the ratio (V _QS ) of

V _QS ≤ 3,

Preferably V _QS ≤ 2,

More preferably, 1.5 ≦ V _QS ≦ 2.

This significantly increases the utilization of the source. In the sputter coating chamber according to the present invention having the above source, this means that the spacing (D) between the new side of the magnetron sputtering source and the substrate is substantially equal to the width of the longitudinally long target device, preferably in the following range A much higher degree is achieved by choosing to be:

60mm ≤D ≤ 250mm,

Preferably 80 mm ≦ D ≦ 160 mm.

In the vacuum coating system according to the invention, with the sputter coating chamber of the invention and consequently the magnetron sputtering source according to the invention, each target device is connected to an electrical generator or a current source which can be controlled independently of one another. do.

The sputter coating system according to the invention with at least three long target devices is preferably such that the two outer target devices are operated with 5-35%, preferably 10-20% more sputtering power than the inner target device. Manipulated.

In another embodiment, or if necessary, when a plurality of installed target devices are connected with the generator device, at least two target devices are connected with an output of a common AC generator.

As a generator for independently supplying power to a target device, a direct current generator, an alternator, a combined direct current alternator, and a generator for outputting a pulsed DC signal may be used. In particular, a generator output may be provided between each target device and the direct current generator. A chopper device can be installed that adjusts, has low resistance and is placed at the generator's reference potential. For this technique, reference may be made to EP-A-0 564 789 and US patent application Ser. No. 08/887 091.

In addition, the gas inlet pipe installed on the longitudinal side of the target device is connected to the gas tank 53 containing the reactive gas and the working gas such as argon, the gas of the gas inlet pipes installed along the longitudinal side of the plurality of target devices as described above Flow rates are controlled independently of each other.

The "scanning" of the target device in relation to the location of the plasma zone, and in particular the "wobbling" of the tunnel-like magnetic field and the plasma density distribution, is realized by a magnetic drum of pendulum motion, preferably from 1 Hz to 4 Hz, preferably Preferably at a frequency of about 2 Hz. The amplitude of the drum is preferably φ ≦ π / 4. By properly designing the path / time profile of the position potential, the coating thickness distribution on the substrate is more optimized.

For this purpose it should be emphasized that the generator connected to the target device can also be controlled to output interdependent, time modulated signals.

In addition, the power supply of the target device, and / or the dispersed gas inlet tube, and / or the magnetic field distribution are controlled or modulated over time so that a desired film thickness distribution on the substrate, preferably a uniform film thickness distribution, is achieved.

Magnetron sputtering sources are preferably

Operating at a power density (p) of 1 W / cm ² ≤p ≤ 30 W / cm ² ,

Especially when sputter coating a reactive film, in particular an ITO film, from a metal target

Operating at a power density (p) of 1 W / cm ² ≤p ≤5 W / cm ² ,

When sputter coating a metal film

It operates at a power density p of 15 W / cm ² ≤ p ≤ 30 W / cm ² .

As can be seen in the magnetron sputtering source according to the invention, in particular in target plate devices which are much longer than the width, the magnetic field strength at the side of the target device is particularly different when the target device is viewed in the longitudinal direction. It is basically advantageous to design it.

However, this fact generally applies only to long magnetron sources.

For this reason, in the long magnetron source according to the invention, which includes a magnet system which changes over time and preferably moves, it is proposed to install a magnet frame, preferably a permanent magnet frame, on the target device. The magnetic field strengths of the frame magnets measured in a given chamber direction are differently designed along the longitudinal side of the target device. In order to compensate for the deflection forces acting on the turning electrons, these magnetic field intensities are preferably designed to be locally different while being basically mirror symmetrical relative to the target diagonal.

The present invention is particularly suitable in all aspects, particularly for sputter coating of large area and preferably flat substrates by reactive processes, preferably with ITO films. The invention is also particularly suitable for coating substrates, in particular glass substrates, used in the manufacture of flat panel display panels, such as TFT or PDP panels, wherein large substrates, for example semiconductor substrates, are subjected to reactive or non-reactive processes, Preferably the possibility of sputter coating with high efficiency at minimal reject rates by the reactive process is basically open.

In sputter coating processes, in particular ITO coating processes, low discharge potential is essential to achieve high film quality, especially low film resistance, without a tempering step. This is achieved by the source according to the invention.

It is also achieved by efficient suppression of arc discharges.

The content of the present invention will be described in more detail with reference to the drawings.

1 shows a basic configuration of a magnetron sputtering source 1 according to the present invention. It comprises at least two, or as shown, for example three long target devices 3a, 3b, 3c. Ancillary devices provided on the magnetron sputtering source, such as magnetic field sources, cooling devices, etc., are not shown in FIG. The source 1 is provided with a separate electrical connection 5 in each target device 3. For example, strip-shaped cathodes 7a, 7b are preferably provided between the target devices 3 which are spaced from one another in the longitudinal direction.

Since the target device 3 is electrically insulated from each other and has individual electrical connections 5, independent electrical wiring is possible as shown in FIGS. 2 and 3.

As shown in FIG. 1, each target device 3 is connected to a generator 9, which can be controlled independently of one another and need not necessarily be of the same kind. As schematically shown, the generators are all of the same kind, or choppers for direct current generators, alternators, alternators and direct current generators, generators for pulsed DC signal output, or intermediate generator outputs and corresponding target devices. ) Can be any combination of generators with units. The structure and operating principle of the generator are described in detail in EP-A-0 564 789 or US patent application Ser. No. 08/887 091.

Also for the electrical operation of the negative electrode 7, the negative electrode is operated by direct current voltage, alternating current voltage, alternating superimposed direct current voltage, or pulsed direct current voltage, or through one of the interrupter units, or shown at 12a. It is completely free in that it can be connected to a reference potential as shown. By varying the positive electrode or target device mode and possibly the negative electrode mode, distributed over the source surface formed by the target devices, the distribution of sputtered material on a substrate (not shown) arranged on the source can be controlled.

In order to specifically modulate the electrical operating conditions on top of the target device in the form of a traveling wave, the generator 9 is interdependent as shown by the modulation inputs MOD. Can be modulated over time.

2 and 3 show additional electrical wiring of the source 1 that does not require a cathode device according to the invention, while maintaining the same position symbol.

As shown in Figs. 2 and 3, the target devices 3 are paired and connected to the inputs of alternators 15a, 15b or 17a and 17b respectively, where the generators 15 or 17 are alternating superimposed direct current signals or pulsed direct currents. Can output a signal. If necessary, the generator 15 or 17 is modulated by amplitude modulation.

The target device 3b according to FIG. 2 is connected to the input of one of the generators 15a and 15b, while the target device 3 according to FIG. 3 is connected in pairs via the generator 17. As shown by the dashed line indicated by 19, in terms of the "common mode" signal, as well as in the design according to FIGS. 2 and 3, the respective target device groups are jointly connected to different potentials. It is possible. When adopting the wiring technique according to FIG. 2 or 3, the generator of the preferred embodiment is operated at 12-45 kHz. With respect to the "common mode" potential, for example the mass potential shown in FIG. 2, target devices connected to the generator in pairs are alternately connected to the positive and negative potentials.

As can be seen from FIGS. 1 to 3, the magnetron source according to the invention allows very high flexibility to electrically manipulate each target device 3, resulting in sputtering in the processing chamber 10. The distribution of materials and the deposition on the substrate can be specifically designed.

4 is a cross-sectional view of a preferred embodiment of the magnetron sputtering source according to the present invention. As shown in FIG. 4, the target device comprises one target plate 3 _a1 or 3 _b1 , each of which consists of a material to be sputtered and is coupled to one back plate 3 _a2 or 3 _b2 , respectively. By means of a linear bayonet unit 20, the target device 3 is fixed to the metal cooling plate 23 at their side edges and / or central parts.

The form of a linear bayonet unit is shown in FIG. 5. According to FIG. 5 a hollow rail 25 is provided on the target device 3 or the cooling plate 23, which is in the form of a U-shaped cross section, on the inwardly curved U-leg 27. Recesses 29 are formed at regular intervals. In the other of the two parts (ie the target device 3 and the cooling plate 23), preferably the target device 3 is provided with a linear rail 31 having a T-shaped cross section, wherein The edge of the cross-member 33 is characterized by the protrusion 34. By inserting the protrusion 34 into the recess 29 and linear shifting in the S direction, the two parts are engaged with each other. Of course, on the contrary, it is also possible to form a projection in the hollow rail 29 which engages a corresponding recess on the linear rail 31.

The target device 3 is fixed to the cooling plate 23 only when pressure is applied by the refrigerant in the cooling channel 35 of the cooling plate 23. This channel 35 extends along a noticeably flat area of the target device surface facing the cooling plate 23. The cooling channel 35 which is pressurized by the liquid refrigerant under pressure as described above is, for example, as described in detail in CH-A-687 427 of the application by the membrane 37 in the form of a target device ( 3) is sealed against. The foil 37 is pressed against the bottom of the back plates 3 _a2 , 3 _b2 under refrigerant pressure. The target device is firmly fixed to the bayonet unit only when the refrigerant is pressurized. In order to remove the target device 3, by reducing the pressure of the entire cooling system or the cooling system, the target device can be easily pushed out and removed or replaced.

An anode strip 39 is installed on the longitudinal side of the target device 3. The negative strip and cooling plate 23 are at least partly mounted on a support base 41 made of an insulating material, preferably plastic. The base 41 serves to separate the vacuum atmosphere in the processing chamber 10 and the atmosphere in the outer space 11.

On the atmospheric side of the base 41, for example, two permanent magnet drums 43 extending along the longitudinal axis of the target device are provided in a rotational manner, which are driven in a pendulum motion by a motor (not shown). . In pendulum motion, they are preferably 180 degrees of pendulum motion ( 43). Permanent magnet drums 43 are provided along the longitudinal axis of the drum, preferably opposite permanent magnets 45.

In addition, one permanent magnet frame 47 is installed at each of the target devices 3 at the atmospheric side of the base 41, and the permanent magnet frame 47 is under the target device 3 as shown in FIG. 6. At that stretches along the edge of the target device.

In particular, a gas inlet tube 49 extends along the longitudinal side of the target device as shown in FIG. 6, and as shown by the dotted lines in FIG. 4, the respective gas flow rates are preferably independent of each other in sequence. Can be controlled. This is schematically illustrated using a servo valve 51 in FIG. 4, wherein the servo valve 51 is a gas tank device 53 and an inlet pipe containing a working gas such as argon and / or a reactive gas. Are provided at the connections between the 49.

The operation and design of the permanent magnet drum 43 is described in detail in European Patent EP-0 603 587 or US Patent US-A-5 399 253.

6 is a schematic top view of the magnetron source according to the invention shown in FIG. 4. As already shown in FIG. 4, a permanent magnet frame 47 is provided below each target device 3. Preferably, the magnet frame 47 has a longitudinal direction of the target device 3 in which the magnetic field generated by the permanent magnet frame is shown by x in FIG. 6 when viewed in the chamber direction, for example along H _Z in FIG. 4. It is designed to change locally along the side. In a preferred embodiment, the magnets installed on the longitudinal legs 47 _I1 , 47 _I2 of the frame 47 are divided into a number of areas, for example four areas as shown in FIG. 6. In FIG. 6, the magnetic field strengths of the permanent magnets installed in each of the regions Z ₁ to Z ₄ are qualitatively illustrated by the coordinate x, and thus the magnetic field intensity distribution is illustrated in the x direction. In addition, the direction of the permanent magnet dipole is shown in the Z region.

The sides 47 _I1 and 47 _I2 are preferably provided with the same permanent magnet area, but are mirror symmetrical with respect to the diagonal D ₁ of the long target device 3.

By specially designing the local magnetic field distribution on the target device 3 resulting from the permanent magnet frame 47, it is possible to optimize the trajectory of the turning electrons and consequently the position and shape of the erosion bones on each target device. Will be. In particular, the above should take into account the orbital deformation caused by the drift force. On the broad side of the target frame 47, a permanent magnet zone Z _B corresponding to the zone Z ₂ is preferably provided. As mentioned above, the single-target source according to FIGS. 4, 6 and 7 is also included in the present invention.

The magnetic field H, which changes locally in the x direction at the top of the target device 3 and changes as a function of the magnetic drum-pendulum motion and also with time, determines the magnetic field strength of the permanent magnets installed in the zones Z ₁ , Z ₂ , Z ₄ . In addition, it is specially designed through the selection of spatial dipole orientation and position (distance from the target device) in the region Z ₃ .

As described above, at least two permanent magnet drums 43 are provided in each of the target devices 3 provided in the sputtering source according to the present invention. Such a drum is shown in FIG. 7.

Preferably, the drum 43 is also provided with various permanent magnet regions (eg, Z ′ ₁ to Z ′ ₄ ). 7 qualitatively shows the progression along a drum in which a permanently changing permanent magnetic field H _R (x) is installed.

In the source according to the invention, the location and time distribution of the sputtering rate is optimized by the specific location and / or time distribution of the power source of each target device and / or the specific of the magnetron magnetic field on each target device. Optimized by position and / or change over time, and / or optimized through specific position and / or change over time or design of gas inlet conditions into inlet tube 49. In the preferred embodiment described in FIGS. 4 to 7, the combination of these variables makes it possible to design a uniform coating thickness distribution on a substrate to be sputter coated, in particular on a flat substrate.

8 schematically shows a sputter coating system 50 of the present invention with a sputter coating chamber 60 according to the present invention, and also a magnetron sputtering source 10 according to the present invention. In a preferred embodiment, the source 10 is equipped with six target devices, and is preferably designed as described based on FIGS. 4 to 7. The source according to the invention with the target device is powered by an independent power source (possibly modifiable) as shown in block 62. The gas inlet condition, which can also be adjusted along the longitudinal axis of the target device, as shown by the servovalve 64, is optionally set to supply working gas and / or reactive gas from the gas tank 53 to the processing chamber.

A drive for a permanent magnet drum installed in a source according to the invention, in which the path / time can be modulated, is shown in drive block 65, in which the desired drum pendulum motion can be selectively set.

The sputter coating chamber 60 according to the invention is provided with a substrate support 66, in particular for fixing the flat substrate to be coated. The source according to the invention can optimally adjust the distribution over time and position of the material to be sputtered by the source 10, in particular the uniform distribution averaged over time in the edge region of the source, resulting in a substrate to be coated. It is possible to make the ratio V _QS of the sputtering surface F _Q of the source to the surface F _S surprisingly small,

V _QS ≤ 3,

Preferably V _QS ≤ 2,

More preferably, 1.5 ≦ V _QS ≦ 2.

This ratio shows that the sputtered material from the sputtering source is used at a very high efficiency because almost all of the sputtered material is deposited on the substrate surface. The spacing D between the substrate surface to be sputtered and the new surface of the magnetron source 10 is very small, ie substantially the width B of the stuffing surface of the target device 3 (see FIG. 4). Equally, and preferably, they may be selected within the following ranges:

60mm ≤D ≤250mm,

Preferably 80 mm ≤ D ≤ 160 mm.

By realizing such a narrow gap D, a high coating speed with high sputtering efficiency is achieved, which enables a very economical coating process.

In the system shown in FIG. 8, the outer target device is operated by the generator 62 at a higher sputtering power, preferably 5-35% higher, more preferably 10-20% higher than the internal target device. . The permanent magnet drum installed in the source 10 according to FIG. 4 is operated in a pendulum mode with a frequency of 1-4 Hz, preferably about 2 Hz.

In a particularly preferred operation, the magnetron sputtering source, sputtering chamber or system is particularly suitable for economically magnetron sputter coating a large area flat substrate with a high quality film having a desired film thickness distribution, in particular a uniform thickness distribution. This is achieved by process conditions uniformly distributed over a large area in the source according to the invention. As a result, the present invention can be used for coating large area semiconductor substrates, in particular for substrates for flat display panels such as TFT or PDP panels. The present invention is particularly used for reactive coating of the substrate with an ITO film or for metal coating of the substrate via non-reactive sputter coating. The following examples summarize the preferred dimensions of a source, chamber or system according to the present invention.

1. Geometric form

1.1 source

Lateral distance d according to FIG. 4: up to 15%, preferably up to 10%, more preferably up to 7% of the target device width B, or

1 mm ≤ d ≤ 230 mm,

Preferably 7 mm ≦ d ≦ 20 mm.

A new surface of the target device on the same plane;

Width of target device (B):

  60 mm ≤ B ≤ 350 mm,

  Preferably 80 mm ≦ B ≦ 200 mm.

Length (L) of the target device: at least B, preferably much longer than B,

  Preferably 400 mm ≤ L ≤ 2000 mm.

Corner of target: for example semicircular.

1.2 Source / Substrate:

Ratio of dimensions (V _QS ) of the sputtering face (F _Q ) to the dimensions of the substrate surface (F _S ) to be coated:

V _QS ≤ 3,

Preferably V _QS ≤ 2,

More preferably 1.5 ≦ V _QS ≦ 2.

Minimum distance between new source side and coated side (D):

  60 mm ≤ D ≤ 250 mm,

  Preferably 80 mm ≦ D ≦ 160 mm.

Substrate size: 750 x 630 mm ² for coating with a source with a sputtering face of 920 x 900 mm ² , or 1100 x 900 mm ² for coating with a source with a sputtering face of 1300 x 1200 mm ² .

1.3 Cooling:

Ratio of sputtering face to cooling face (V _SK ):

1.2 ≤ V _SK ≤ 1.5.

2. Operating Variables

Target temperature (T):

  40 ° C. ≦ T ≦ 150 ° C.,

  Preferably 60 ° C. ≦ T ≦ 130 ° C.

Sputtering power per unit sputtering area:

10-30 W / cm ² ,

Preferably 15-20 W / cm ² .

The outermost target device on each side is operated at 5-35%, preferably 10-20% higher sputtering power per unit area.

Pendulum frequency of the magnetic drum: 1-4 Hz, preferably about 2 Hz.

                                  result

The following coating rates are achieved:

ITO: 20 ms / s

Al: 130-160 Hz / s

Cr: 140 μs / sec

Ti: 100 μs / sec

Ta: 106 μs / sec.

9 shows the erosion profile on a 15 cm wide sputtering surface in the target device of the source according to the invention. Because of the very uniform erosion, little "race track" or erosion profile is observed.

10 shows the distribution of ITO sputtering coating rates in a source according to the invention with five target devices each having a sputtering face 150 mm wide (B). In this distribution, the film thickness deviation on the substrate provided at 120 mm intervals D from the source surface was only ± 3.8%.

FIG. 11 shows the film thickness distribution on a large area glass substrate coated as follows:

Total sputtering power (P _tot ): 2 kW

Sputtering Time: 100 seconds

Coating speed (R): 26 s / sec, relative coating rate: 13 s / sec, kW

In the source consisting of six target devices, the outermost target device was operated with 10 or 15% higher sputtering power (P ₁ , P ₆ ), respectively.

Substrate size: 650 x 550 mm ² .

FIG. 11 shows the edge region of the substrate on top of the target device operated with increased sputtering power. In the ITO coating process, the film thickness deviation over the average film thickness of 267 nm was ± 6.3%.

The present invention provides the following features that can avoid the disadvantages associated with the coating of large area workpieces, especially in known sputtering sources:

According to the present invention, in addition to utilizing a high coating speed and a high sputtering speed, a uniform distribution of process conditions is possible over a large area magnetron sputtering surface, which is very economical when coating a large area substrate or coating multiple substrates at the same time. to be.

Since the source according to the present invention sputters a large area at the same time, the film thickness distribution on the substrate is excellent and the arc phenomenon can be prevented.

Since the problems associated with the uniformity of the reactive gas distribution and / or the target erosion distribution are solved, the substrate to be coated can be placed closer to the source and can be coated with a much larger area than the source side. The economics of the sputter coating system equipped with the source according to the invention can be improved.

In large area targets, the problem of plasma density difference between the target center and the target periphery caused by the cathode member of the target center can be solved.

The source can be flexibly adapted to the dimensions required by the modular target device.

Since the gas inlet pipe 49 can be dispersed on the source surface, it is possible to solve a problem in which a lean phenomenon of the reaction gas occurs in the center of the target in the large-area target.

Since the base 41 is located between the process vacuum and atmospheric pressure (see FIG. 4), it is no longer necessary to install a thick cooling plate 23 that can alleviate this load. This makes the source less complicated, and the magnetic field passing through the magnetic devices 47 and 43 installed under the target device 3 is good.

Through selective control of the following distributions, the film thickness distribution of the large area substrate can be optimally and particularly uniformly adjusted:

  Electrical operation over time and / or location of the target device;

  Magnetic actuation according to the time and / or location of the target device; And

  Gas inlet over time and / or location.

By providing the bayonet unit in addition to the fixing of the target device through the refrigerant pressure, it is possible to simply and quickly replace the target device and effectively cool the large area.

Due to the bayonet unit installed below the sputtering face, fixing elements, in particular fixing elements made of a material other than the sputtering material, are not exposed towards the processing chamber.

1 is a schematic diagram of a first embodiment of a magnetron sputtering source according to the present invention operated electrically;

2 is another electrical circuit diagram of the sputtering source according to FIG. 1, FIG.

3 is another electrical circuit diagram of a sputtering source according to the present invention shown similarly to FIG.

4 is a cross-sectional detail view of a magnetron sputtering source according to the present invention;

FIG. 5 is a plan view of a linear bayonet unit used for the source according to FIG. 4, FIG.

6 is a top schematic view of a magnetron source according to the present invention;

7 is a plan view of a preferred embodiment of a permanent magnet drum provided in the magnetron sputtering source of the invention according to FIG. 6, FIG.

8 is a schematic view of a sputter coating system according to the present invention;

9 shows an erosion profile on a target device of a source according to the invention,

10 shows the distribution of sputtered material formed on a source according to the invention with five target devices installed; and

FIG. 11 shows a relief pattern of a film thickness formed on a glass substrate of 530 × 630 mm ² size coated using a source according to the present invention.

Claims (24)

A sputter source having two or more electrically isolated stationary stationary target arrangements, each target device comprising a respective electrical pad, such that each target device is independent of the other target device. And a controlled magnet arrangement that can be electrically manipulated such that each target device generates a time-varying magnetron field for each target device. The source of claim 1, wherein the source further comprises a cathode device comprising cathodes arranged side by side between the target devices and / or along a narrower side of the target devices. The source of claim 1, wherein the magnet devices comprise a frame having electromagnets and / or permanent magnets along the target devices. 2. The source of claim 1, wherein the magnetic devices each generate a tunnel-shaped magnetic field on each target device such that the peaks of the tunnel-shaped magnetic field change over time. 5. The source of claim 4, wherein the magnet device generates a tunnel-like magnetic field on each target device such that the positions of the vertices of the tunnel-shaped magnetic field respectively change over time. The source of claim 1, wherein the magnet device comprises drums rotatable or rotatable by power with two or more permanent magnets and / or electromagnets, respectively. The source of claim 1, wherein the target devices are mounted on a base, the base comprising a cooling medium channel arrangement adjacent to each of the target devices and sealed by a foil. The source of claim 1, wherein the source further comprises a gas inlet arrangement having a gas inlet opening disposed side by side with the target devices. 2. The gas inlet arrangement of claim 1, wherein said source has a gas inlet arrangement having a gas inlet opening disposed side by side with said target devices, and an adjusting unit for adjusting a gas inlet distribution at said gas inlet opening. Source additionally containing an adjustment unit. The source of claim 1 wherein the target devices are spaced apart from each other by an interval that is less than 15% of the width of one of the rod-shaped target devices. The source of claim 10 wherein said spacing is no more than 10% of said width. The source of claim 11, wherein said spacing is no more than 7% of said width. The source of claim 1 wherein the length of the rod-shaped target devices is much greater than their width. The source of claim 13, wherein the length, L, is 400 mm ≦ L. The source of claim 1, wherein the target devices are spaced apart from each other by a distance d, wherein d is 1 mm ≦ d ≦ 230 mm. The source of claim 15 wherein d is 7 mm ≦ d ≦ 20 mm. 15. The source of claim 14, wherein each width of said target device is B and B is 60 mm < B < 350 mm. 18. The source of claim 17, wherein B is 80 mm < B < 200 mm. The source of claim 1, wherein the sputtering surfaces of the target devices in an unsputtered condition are substantially arranged on the same plane. The source of claim 1, wherein the magnetic devices, when instantaneously considered, generate a magnetic field that varies locally along the length of the rod-shaped target devices. The source of claim 1, wherein the stationary frame surrounds at least some of the target devices, and wherein the magnets arranged side by side with at least some of the target devices in the frame have different magnetic field strengths. The source of claim 1 comprising more than two said target devices. 23. The source of claim 22 comprising at least five said target devices. A magnetron sputtering chamber comprising the sputter source of claim 1.