JPH11106914A - Counter magnetron composite sputtering device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the capturing efficiency of sputtered particles (increase of the utilizing efficiency of a target), to increase the speed of the formation of coating to be formed on a substrate, to uniformize the coating thickness, to uniformize the coating quality, moreover to stabilize the working of the device for a long period and to improve the working efficiency thereof by composing it in such a manner that the sputtered particles adhered to the parts of the device other than the substrate and obliquely incident components adhered to the substrate are extremely suppressed. SOLUTION: In a state in which, into the inside of one, T2 of two cylindrical targets T1 and T2 , the other T1 is inserted, a doughnut-shaped space is formed on the space between the sputtering faces of these targets, and an another target T3 is furthermore arranged at the bottom part, the space between the cylindrical targets T1 and T2 is applied with the magnetic field vertical to the sputtering face, furthermore, counter discharge is generated on the space between the cylindrical targets T1 and T2 , moreover, magnetron discharge is generated on the target arranged at the bottom part, and thin film is formed on a substrate arranged so as to face to the opening of the head of the cylindrical structure (doughnut-shaped space).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an outer peripheral surface of an outer cylindrical member, an outer peripheral surface of an inner cylindrical member, and a double-layered structure having an outer cylindrical member and an inner cylindrical member arranged concentrically at a predetermined interval. A facing magnetron composite sputtering apparatus for arranging a target at one end and arranging a substrate facing the other opening, and forming a thin film or the like on the substrate using a sputtering surface formed by these targets. Regarding, it is easy to adjust the film thickness distribution of the formed thin film, it is possible to form a uniform film thickness for a long time, it can be formed in a large area at high speed, and the trapping efficiency of sputtered particles jumping out of the target is improved and The present invention relates to a facing magnetron composite sputtering apparatus capable of suppressing a flying sputter particle as much as possible and forming a stable film for a long period of time.

[0002]

2. Description of the Related Art A conventional facing target type sputtering apparatus is described in "Applied Physics", Vol. 48 (1979) No. 6, p588-p.
As shown in FIG. 559, as shown in FIG. 7, a pair of targets t1 and t2 serving as cathodes are provided so that their sputtering surfaces face each other with a space therebetween, and a magnetic field H in a direction perpendicular to the sputtering surface is generated. Means h1 and h2 for forming a thin film on the substrate 5 attached to the holder 6 disposed on the side of the space between the targets. is there.

[0003] That is, in FIG.
If a magnetic field H of 300 to 500 Oe is generated in a direction perpendicular to the sputtering surfaces t1s and t2s at 1 and t2, high-energy electrons emitted from the sputtering surfaces t1s and t2s can be confined in the space between the opposed targets. it can.

[0004] Therefore, since many electrons do not reach the substrate 5, an electric field for converging the ions is not formed, and ionization of the formed sputtering gas is promoted to increase the sputtering speed. Further, since there is almost no electron collision with the substrate 5, the substrate temperature does not rise so much.

In a magnetron sputtering apparatus, "a magnetron sputtering apparatus having a flat target and a concave target" (Japanese Patent Laid-Open No. 61-39522).
And "a sputtering cathode for coating a substrate with a cathode sputtering apparatus" (Japanese Patent Publication No. 6-43030).

In particular, the shape of the "sputter cathode for coating a substrate with a cathode sputtering apparatus" is similar, but the main discharge mode of sputtering is magnetron discharge, and the projections confine the magnetron discharge. This is a cathode configuration in which the distance is extended to a position where the light is incident substantially perpendicularly. By arranging the magnet end surface at a position above the sputtering surface, a high gradient change of the magnetic field intensity due to the target erosion is significantly reduced, and an effect that a very thick target can have constant sputtering characteristics for a long period of time is obtained.

[0007]

However, in the apparatus for performing sputtering with the above-described opposed target apparatus having a rectangular target, the substrate can be brought close to the target by making use of the features of the opposed target. It is very difficult to employ a device structure that captures sputter particles by flying in various directions from the target side surface (the end in the surface direction of the target) and arranging the substrate in all directions. Generally, substrates are arranged in one or two directions. However, sputtered particles flying from an end space where the substrate is not disposed may reach the inner wall of the chamber, a substrate transfer mechanism, or the like, and cause film deposition there.

In the case of a magnetron sputtering apparatus, when the target is brought close to the substrate, there may be a case where the substrate temperature rises due to heat radiation from the target surface, electrons, ion impact, etc., or the film quality deteriorates due to ion damage. In order to avoid such an influence, in the case of magnetron sputtering, it is common to have a substrate distance of 50 mm or more. When the substrate distance is 50 mm or more, the sputtered particles that have passed through the gap between the target and the substrate may reach the inner wall of the chamber, the substrate transfer mechanism, or the like, as described above, and may cause film adhesion. A film that has adhered to the inner wall of the chamber or the substrate transfer mechanism for a long period of time may cause abnormal discharge, contamination of the film, trouble in the transfer system, etc. through peeling, etc. The adsorption of moisture and the like causes a reduction in the exhaust speed.

In the facing sputtering apparatus, it is possible to bring the target and the substrate close to each other, but there is a phenomenon that the erosion region of the target is concentrated at the center of the target with an increase in the power applied to discharge. In particular, such a phenomenon is remarkable when the target is a non-magnetic material. Such concentration of the erosion region not only adversely affects the film thickness distribution, but also causes a spark when a large power is applied in order to increase the speed of sputtering, which is not preferable.

On the other hand, in the case of magnetron sputtering, as described above, it is very difficult to bring a substrate close due to a rise in substrate temperature or ion damage, and therefore it is preferable to secure a substrate distance of 50 mm or more. When a suitable target-substrate distance is adopted, the sputter particles adhering to the substrate decrease (rate decrease) due to the scattering of sputter particles and the like, and the sputter particle oblique incidence component in the film differs between the central part and the peripheral part of the film, and the film thickness distribution And adversely affect film quality.

Furthermore, in order to cope with a large-area substrate, a measure is taken to improve the film thickness distribution in the longitudinal direction by increasing the length in the longitudinal direction of the target with respect to the effective width of the substrate. Although the method in which the substrate passes through the side surface of the space between the opposed targets has been adopted, this method has disadvantages such as a decrease in the effective utilization rate of the target and the film formation rate, and an increase in the size of the apparatus. It was not always an effective method.

It is an object of the present invention to improve the capture efficiency of sputter particles (increase the target use efficiency) by minimizing sputter particles adhering to an apparatus portion other than the substrate and oblique incident components adhering to the substrate. Another object of the present invention is to increase the film forming rate on a substrate at a high speed, to make the film thickness uniform, to keep the film quality constant, to further stabilize the operation of the apparatus for a long time, and to improve the operation efficiency.

[0013]

The opposed magnetron composite sputtering apparatus according to the present invention comprises a cylindrically arranged second target concentrically arranged outside and inside a cylindrically arranged first target. A sputter surface forming an inner peripheral surface of a cylindrical shape formed by the second target is opposed to a sputter surface forming an outer peripheral surface of a cylindrical shape formed by the first target at a predetermined distance. Target placement means for placing the first target and the second target so as to cover the bottom of the space between the first target and the second target, and place the third target so that the sputtering surface is located opposite to the space. A bottom holding means for arranging a substrate in a space between the first target and the second target, and arranging a substrate in opposition to the opening; And in a direction perpendicular to each of the second sputtering surface a facing magnetron composite sputtering apparatus and a magnetic field generating means for generating a magnetic field,
The main discharge formed on the sputter surfaces of the first and second targets is a facing discharge, and the main discharge formed on the sputter surfaces of the third target is a magnetron discharge.

According to the thin film forming method of the present invention, a second target disposed in a cylindrical shape is concentrically disposed outside a first target disposed in a cylindrical shape, and the first target is formed by the first target. The sputter surface forming the inner peripheral surface of the cylindrical shape formed by the second target is opposed to the sputter surface forming the outer peripheral surface of the cylindrical shape at a predetermined distance,
A sputter surface of a third target is arranged at the bottom of the space between the first target and the second target, and a head of the space between the first target and the second target is an opening, A substrate is arranged to face the opening, and in a state where a magnetic field is applied in a direction perpendicular to each of the first and second sputtering surfaces, a facing discharge is generated on the sputtering surfaces of the first and second targets. At the same time, a magnetron discharge is generated on the sputter surface of the third target to form a thin film on the substrate.

According to the present invention, by disposing the third target at the bottom of the space between the opposing first target sputtering surface and the second target sputtering surface, sputtered particles from the bottom can be removed. Diffusion is prevented, and the sputtered particles are efficiently supplied from the opening at the head of the sputter surface onto the substrate provided opposite to the opening. That is, it is possible to effectively prevent unnecessary thin film formation in a device portion other than the substrate.

[0016] Further, a facing discharge is generated between the first target and the second target, and a magnetron discharge is generated in the third target, so that the capture efficiency of the sputtered particles is further increased (the target use efficiency is increased). ) It is possible to increase the film forming rate formed on the substrate at a high speed, to make the film thickness uniform, to keep the film quality constant, to further stabilize the operation of the apparatus for a long time, and to improve the operation efficiency.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of a sputtering apparatus according to the present invention will be described with reference to the drawings. 1 to 3 are views showing the main parts of an example of the sputtering apparatus of the present invention. FIG. 1 shows a double cylindrical structure composed of a first target and a second target, that is, a double cylindrical structure in which a donut-shaped space is formed between the first target and the second target. FIG. 2 is a longitudinal sectional view in the direction of a concentric axis, FIG. 2 is a plan view from the head opening side in the case of using cylindrical first and second targets, and FIG. It is a top view from the head opening side at the time of using a 1st and 2nd target. Although the axis of the double cylindrical structure is arranged in the horizontal direction in FIG. 1, the arrangement direction of this axis is not limited to the illustrated example, and can be changed as desired.

In FIG. 1, reference numeral 10 denotes a vacuum chamber capable of evacuating the inside, reference numeral 20 denotes an exhaust system including a vacuum pump for exhausting the chamber 10, and reference numeral 30 denotes a gas introduction system. As shown in the drawing, a target holder 14 is fixed in the vacuum chamber 10 via the chamber 10 and insulating members 11, 12, and 13. The holder 14 has a pair of cylindrical targets T1 and T2. Are disposed so as to face each other in parallel, and the targets T1 and T2
A donut-shaped flat plate target T3 is provided on the side surface.

Behind the targets T1 and T2, cylindrical permanent magnets 15 and 16 which are magnetic field generating means are arranged to face each other. Cooling water circulates through the cooling pipes 171 and 172 in the portions of the targets T1, T2 and T3 and the corresponding target holders 14 so that the targets T1, T2 and T3 and the permanent magnets 15 and 16 are cooled. Has become. The magnets 15 and 16 are the target T
A core made of a ferromagnetic material, such as permalloy or soft iron, is provided so that the north pole and the south pole face each other with respect to T1 and T2, and in order to increase the magnetic flux density in the space between the pair of cylindrical targets T1 and T2. At 18, a closed loop of the permanent magnets 15, 16 is formed. The core 18 is connected to the magnetic field moving means 70 and can move and adjust in parallel with T1 and T2. Reference numeral 19 denotes a shield cover used as the insulating members 11 and 12, the target holder 14, and the shield plate, and also functions as an anode.

A substrate holding means 41 for holding a long substrate 40 on which a thin film is formed is held perpendicularly to the sputtering surfaces of the targets T1 and T2 by a substrate transfer system 50, and is perpendicular to the plane of the drawing. Can reciprocate in any direction. Accordingly, the substrate 40 can also move in a direction perpendicular to the sputtering surfaces of the targets T1 and T2. The heating means 42 capable of adjusting the temperature from the back surface of the substrate 40
have.

On the other hand, a power supply means 60 composed of a DC power supply for supplying sputtering power has the plus side connected to the ground and the minus side connected to the targets T1, T2 and T3, respectively. Note that a shutter (not shown) is provided between the substrate 40 and the targets T1 and T2 to protect the substrate 40 during pre-sputtering.

By the way, a magnetic field generating means comprising a permanent magnet and a core forming a closed loop is provided behind the targets T1 and T2, and the magnetic flux 80 crosses the surface of the target T1 vertically from the magnet at the center and further forms a space. The target crosses the surface of the target T2 installed on the outer periphery vertically and reaches the outer peripheral magnet. The magnetic flux traversing the outer magnet passes through the inside of the core made of ferromagnetic material and reaches the inner magnet to form a closed loop. By forming a closed loop in this manner, a magnetic field that crosses the surfaces of the targets T1 and T2 perpendicularly can be formed efficiently. With the magnets 15 and 16 fixed to the core, the position can be adjusted by the magnetic field moving means connected to the core so that the opposing magnetic field and the magnetron magnetic field are optimized, and the opposing discharge and the magnetron discharge can coexist.

When the opposing discharge of a set of targets and the magnetron discharge of the target T3 are performed with the same power supply, the impedance of each discharge is different.
In order for the respective discharges to coexist, the following conditions are preferably satisfied.

1) Surface of target T3 (sputtered surface)
And the maximum magnetic flux density Bm parallel to this surface and the target T
The relationship between the maximum magnetic flux density Bt in the direction perpendicular to the sputtering surface of the targets T1 and T2 at the center of T1 and T2 is B
t> Bm.

2) As shown in FIG.
The height H from the sputtering surface of the target T3 at the upper end of T2
And the relationship between the distance W between the targets T1 and T2 is H ≧
W / 2 is satisfied.

That is, it is preferable to perform discharge under a discharge condition having a low discharge impedance (voltage and current characteristics). When the discharge area is the same and the maximum magnetic flux density is Bt = Bm, the voltage determined by the magnetron discharge is supplied to the target because the impedance of the magnetron discharge is lower. As for the flowing current, the magnetron discharge having a lower impedance has a larger current flow, and a larger power than the target of the opposed discharge is supplied. In order to avoid such a problem, it is necessary to lower the impedance of the facing discharge and increase the impedance of the magnetron discharge. Specifically, there are a method of 1) increasing the maximum magnetic flux density Bt contributing to the opposing discharge and decreasing the maximum magnetic flux density Bm contributing to the magnetron discharge, and a method of 2) making the opposing discharge area larger than the magnetron discharge area. Therefore, in 1), the magnetic field is generated by the inner target T
Means for radially generating from the first target T2 to the outer target T2 and a magnetic field generating means are disposed closer to the targets T1 and T2 than T3s, and the sputtering surfaces T1 of the pair of targets T1 and T2 are arranged.
By providing a means that can move in parallel to s and T2s, the intensity of the magnetic field can be adjusted, and the discharge impedance can be adjusted. In 2), when H = D / 2, since the area of the opposed discharge and the area of the magnetron discharge are equal, the condition of H> D / 2 is necessary for lowering the impedance of the opposed discharge and increasing the impedance of the magnetron discharge. Become.

By satisfying and adjusting the above conditions, a counter discharge can be formed in the targets T1 and T2 without a magnetron discharge being biased in the target T3, and the following advantages can be obtained.

A) Since the discharge in the portion close to the substrate is a counter discharge, low temperature film formation, which is an advantage of the counter discharge, can be utilized.
The substrate can be arranged as close as possible to the target.
According to such a configuration of the cathode and the substrate, the sputtered particle formation region is surrounded by the sputtered surfaces of the targets T1, T2 and T3, and the sputtered particles are captured by another sputtered surface or the substrate, and Improve particle capture efficiency (improve target use efficiency)
I can do it. In addition, it is possible to reduce the film formation on the inner wall of the chamber other than the substrate and the substrate transfer mechanism as much as possible, and to improve the deterioration of the film quality due to the residual gas, the reduction of the pumping speed, the contamination of the film with the dust, etc. It is possible to reduce trouble of the transport mechanism. From this point of view, the opening of the space between the targets T1 and T2 at the left end in FIG.
Preferably, 3 is arranged so as to occupy substantially the entire closed part.

B) Since the film can be arranged as close to the target as possible, the film formation rate is increased, the sputtered particle component obliquely incident on the substrate, which lowers the film quality and the film thickness distribution, is reduced, and the film thickness distribution is improved and the film quality is improved. Improvements have been made possible.

In the case of a large-area substrate, the target shape is an oval shape as shown in FIG. A thin film can be uniformly formed on a large-area substrate passing through a position facing a surface.

On the other hand, in the double cylindrical structure shown in FIG. 1, a plurality of the double cylindrical structures are arranged in the same apparatus, and one substrate is processed by a plurality of double cylindrical structures. It is possible to improve the film formation speed and the film formation efficiency, for example, by processing one substrate and performing parallel processing on a plurality of substrates.

That is, compared to the prior art, by adopting a configuration in which sputter particles adhering to portions other than the substrate and obliquely incident sputter particle components adhering to the substrate are suppressed as much as possible, the capture efficiency of sputter particles is increased (target use efficiency is increased). The film formation rate formed on the substrate can be increased at a high speed, the film thickness can be made uniform, the film quality can be made constant, and the operation of the apparatus can be stabilized for a long period of time to improve the operation efficiency. Further, the film thickness distribution on a large-area substrate can be made more uniform, and the change in the distribution over time can be reduced to keep the film thickness uniform. Also, by arranging a plurality of sets, the sputtering speed can be increased, and the use efficiency of the target can be improved.

Note that the cylindrical shape of the targets T1 and T2 can be selected as desired as long as the objects and effects of the present invention can be achieved, and the cylindrical shape shown in FIG.
A similar magnetic field can be formed at any position of the target by using the oval shape shown in FIG.

In the examples shown in FIGS. 1 to 3, each target has a continuous one-piece structure. However, these targets can be used as long as they can form a sputter surface of a predetermined shape. It may be a sheet, or may be composed of a plurality of divided parts.

In the apparatus having the above structure, Ar
When a gas such as is introduced and DC power is applied, the target T
A vertical electric field is formed on the surfaces of T1, T2 and T3. When the magnetic field and the electric field are formed in parallel in the targets T1 and T2, the electrons rotate so as to surround the magnetic field, and the gas molecules collide with the electrons and are ionized, so that a facing discharge can be formed. On the surface of the target T3, a magnetic field and an electric field are formed so as to intersect substantially perpendicularly, and electrons are bent and rotated in the circumferential direction of the concentric target while performing cycloidal motion, whereby gas molecules are ionized and a magnetron discharge can be formed in the same manner as described above. Since a negative voltage is applied to the targets T1, T2, and T3 from the DC power supply 60, the ionized gas molecules
Opposing sputter and magnetron sputter, which are drawn while accelerating at 1, T2 and T3 and collide with the target to repel the target material, occur. At this time, as described above, the targets T1 and T2 are cylindrical, and the electric field and the magnetic field are formed perpendicularly and radially to the surfaces of the targets T1 and T2. Counter sputtering occurs in the entire area of the cylindrical target without performing the above, and the effective use efficiency of the target can be improved. Further, the opposing sputtered surface formed by the targets T1 and T2, the magnetron sputtered surface formed by the target T3, and the substrate substantially surround the entire area, and the sputtered particles jumping out of the sputtered surface adhere to the substrate or the target surface. The particles adhering to the target surface are re-sputtered and adhere to the substrate, so that the efficiency of capturing the sputtered particles can be increased and the utilization efficiency of the target can be improved.

In the conventional facing sputtering and magnetron sputtering, the trapping efficiency is low because the space other than the sputtered particles sputtered radially adhering to the substrate is wide, and the electric field and magnetic field unique to facing sputtering are almost parallel. Is formed in the center of the target and the efficiency of use of the target, such as the concentration of the erosion region, was low. However, in the present invention, a large amount of power is supplied in accordance with the increase in the erosion region of the opposing sputtering and the increase in the plasma confinement efficiency. In addition, the distance between the target and the substrate can be reduced, and the deposition rate can be increased, and the capture efficiency of sputter particles can be increased.

Further, it was possible to bring the target closer to the substrate and to reduce the ratio of the oblique incidence component to the film thickness because the targets T1 and T2 became oblique incidence walls, thereby improving the film quality and the film thickness distribution. Since the targets T1 and T2 have different sputtered areas, the thickness of the inner target T1 having a small area is preferably larger than T2 in order to make the target life the same.

Next, uniformization of the film thickness distribution in the longitudinal direction can be maintained by the following method. In general, when the substrate 40 is transported to form a film during sputtering, the film thickness in the transport direction can be made uniform, but the peripheral portion may be thin in a direction perpendicular to the transport direction. In such a case, inconvenience may occur. Instead of the cylindrical targets T1 and T2, targets O1 and T2 having an oval shape as shown in FIG. And arranging a plurality of cylindrical targets more in the periphery than in the center of the substrate, a uniform thin film can be obtained over a large area.

Therefore, according to the present invention, the coexistence of the opposing discharge and the magnetron discharge enables high-speed film formation with a short distance between the target and the substrate as described above. Even in a very small area, the composition ratio of the film adhesion can be increased to increase the former of the composition ratio of the sputtered particles flying from the erosion near the substrate and the sputtered particles flying from the distant erosion. The difference in the emission angle distribution among various targets can reduce the uniformity of the film thickness distribution over a wide area, and optimization can be achieved.

[0040]

【Example】

Example 1 A film forming experiment was performed using the facing magnetron composite sputtering apparatus of the present invention shown in FIGS. 1 to 2 and FIG. First, substrate 4
For 0, a blue plate glass substrate having a thickness of 1.1 mm and a size of 300 mm × 300 mm was used, and targets T1, T2, and T3 were used.
Has a target material of 99.99% pure copper (C
u) was used so that the longitudinal direction of the oval shape was oriented in the direction perpendicular to the substrate transport direction, the inner diameter of the outer target T2 in the longitudinal direction was 320 mm, and the thickness of the outer target T2 was 6 mm. T1 target has a thickness of 12mm and T3
A target having a thickness of 6 mm was used, and the height (H in FIG. 8) of each of the cylindrical targets T1 and T2 was 1
00 mm, the inner target T1 and the outer target T
The distance (W in FIG. 8) between the sputtering surface and the surface 2 is 60 m.
m. The position of the magnet was adjusted by the magnet moving means 70, and the intensity of the magnetic field from the T1 sputtering surface in the direction substantially perpendicular to the T2 sputtering surface at that time was 400 Oe, and the magnetic field intensity in the horizontal direction on the T3 target surface was 150 Oe.

The main conditions for sputtering are Ar
The gas pressure was set to 3 × 10 ⁻³ Torr and the distance from the target end to the substrate was set to 30 mm. (If the distance from the target end to the substrate surface is shorter than 10 mm, plasma damage due to heat, electrons, ions, etc. cannot be ignored. On the other hand, if the distance exceeds 60 mm, the film adheres to the wall surface other than the substrate, the transport drive system, etc., which causes a trouble in the transport system apparatus, and causes the generation of contamination and particles. From 60m
The range of m is preferred. ) In addition, the substrate transfer speed is 1
At a rate of 00 mm / min, a DC electric field of 8 kW was applied to T1, T2, and T3 as a power for sputtering.

A thin film made of copper was formed by sputtering on a glass substrate as described above. The thickness of the copper film formed under these conditions was about 1 μm, and the film thickness distribution in a 300 mm square substrate was measured. As a result, as shown in FIG.
Good results were obtained with an error within 0%. Further continuous sputtering was performed for 24 hours, and the inner wall of the chamber was visually observed. No film adhesion was observed.

Comparative Example 1 As a comparison with Example 1, a similar film-forming experiment was performed using a conventional opposed target sputtering apparatus. The opposite target t1t2 is made of copper (Cu) having a purity of 99.99% as a target material and is 6 mm thick and 320 mm × 1 as a target material.
Using a rectangular target of 00 mm, the long direction of the target was oriented in the direction perpendicular to the direction of transport of the substrate, and the substrate passed through the long surface side. The distance between the targets was 100 mm, and the intensity of the magnetic field from the t1 sputter surface to the direction substantially perpendicular to the t2 sputter surface was 400 Oe as in Example 1. The main conditions of the sputtering were as follows: the Ar gas pressure was 3 × 10 ⁻³ Torr, the distance from the target end to the substrate was 30 mm, and the substrate transfer speed was 150 mm / min.
An 8 kW DC electric field was applied to T1 and T2 as the power for sputtering.

As described above, a thin film made of copper was formed by sputtering on a glass substrate by a conventional method. The thickness of the copper film formed under these conditions was about 1 μm at the center of the 300 mm square substrate.
m, and the film thickness distribution in the 300 mm square substrate was measured. As shown in FIG. 4, the film thickness distribution region of ± 10% was about half of the substrate width of 300 mm, ie, about 150 mm. Further, continuous sputtering was performed for 24 hours, and the inner wall of the chamber was visually observed. As a result, a large amount of film adhered to the inner wall of the chamber, the transfer mechanism, and the like in a direction in which the targets T1 and T2 were not surrounded.

Embodiment 2 Next, the DC power supply 60 was replaced with a 13.56 MHz high frequency power supply, a matching device was mounted between the high frequency power supply and the cathode, and the target material was changed from copper to a 99.99% pure SiO ₂ material. The substrate is 1.1 mm thick and 300 mm square BK-7
A glass substrate was used, and an argon gas and an oxygen gas were introduced as a sputtering gas at a ratio of 9 to 1 to form a film at a high frequency power of 5 Kw and a substrate transfer speed of 30 mm / min. The other conditions were the same as those in Example 1 and Comparative Example 1, and Si and Si were respectively measured using the conventional facing target sputtering apparatus and the facing magnetron composite sputtering apparatus of the present invention.
After forming the O ₂ film, a multi-photometer (MC
Immediately after releasing from vacuum to atmosphere using PD1000),
An experiment was performed to evaluate the film quality based on the change in reflection characteristics after standing for a long time. At that time, the measurement was performed by leaving the substrate in a clean room atmosphere at a temperature of 20 ° C. and a humidity of 45%.

As a result, as shown in FIG. 5, the SiO ₂ film formed by the facing magnetron composite sputtering apparatus of the present invention was used.
The change in the reflection characteristics of the film around the substrate (peripheral direction perpendicular to the substrate transport direction) and the central part did not change from vacuum to immediately after being exposed to the atmosphere and after standing for 5 hours.
In the film formed by the conventional opposed target sputtering apparatus, the change in the reflection characteristic at the central portion of the substrate was not changed as in FIG. 5, but the reflection characteristic at the peripheral portion of the substrate was as shown in FIG. The reflectance decreased, and the change in reflectance after being left for 5 hours immediately after opening to the atmosphere tended to increase.

Example 3 The targets T1, T2, and T3 described in Example 1 and the targets t1 and t2 used in the comparative example were used up to the use limit (immediately before one hole became clear). The weight was measured, and the weight of the film adhered to the substrate (the weight of one film in consideration of the film thickness distribution × the number of processed substrates) was calculated to obtain the sputter particle capture efficiency. The value of (sputter particle capture efficiency) = (weight of film adhered to substrate / (weight before use of target−weight after use of target)) was obtained. As a result, the efficiency of capture of sputter particles by conventional opposed sputtering was about 30%. In contrast, the efficiency of capturing sputtered particles according to the present invention was about 90%.

[0048]

As described above, the present invention has the following effects. (1) Incorporating the advantages of conventional counter sputtering, high-speed low-temperature sputtering can be performed, and the peripheral portion, which was impossible with conventional sputtering, can be efficiently sputtered. Sputtering can be performed. (2) It is possible to reduce dust in the film formed over the entire area of the substrate and to reduce the oblique incident component ratio of sputtered particles to obtain a good film quality. (3) Adhesion of the film on the inner wall of the chamber can be prevented, and the stability of the drive mechanism inside the chamber can be increased, and the stability required for mass production equipment such as fluctuation of the exhaust speed can be improved. (4) A single expensive power supply can provide a discharge in which a counter discharge and a magnetron discharge coexist.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view in the axial direction of a cylindrical target showing a main part of an example of a facing magnetron composite sputtering apparatus of the present invention.

FIG. 2 is a plan view of a double cylindrical structure used in the present invention.

FIG. 3 is a plan view of an oval double cylindrical structure used in the present invention.

FIG. 4 is a diagram showing a comparison of film thickness distribution between Example 1 and Comparative Example 1.

FIG. 5 is a diagram showing a change in reflection characteristics of a SiO ₂ film around a substrate formed by the opposed magnetron composite sputtering apparatus of the present invention.

FIG. 6 is a diagram showing a change in reflection characteristics of an SiO ₂ film around a substrate formed by a conventional opposed sputtering apparatus.

FIG. 7 is a sectional view of a conventional facing sputtering apparatus.

FIG. 8 is a view for explaining an arrangement of a sputtering surface in the apparatus of the present invention.

[Explanation of symbols]

 Reference Signs List 10 vacuum chamber 11, 12, 13 insulating member 14 target holder 15, 16 permanent magnet 18 core 19 shield plate 20 exhaust system 30 gas introduction system 40 substrate 41 substrate holding means 42 heating means 50 substrate transport system 60 power supply means 70 magnetic field movement Means 80 Magnetic flux 171,172 Cooling pipe T1, T2, T3 Target

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Ryuji Bilo 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Hidehiro Kanazawa 3-30-2 Shimomaruko, Ota-ku, Tokyo Non Corporation

Claims (10)

[Claims] 1. A cylindrically arranged second target is concentrically arranged outside a cylindrically arranged first target, and an outer periphery of a cylindrical shape formed by the first target is provided. Opposing target arranging means for arranging a sputter surface, which is a cylindrical inner peripheral surface formed by the second target, at a predetermined distance with respect to a sputter surface, which is a surface of the first target; Bottom target placement means for covering a bottom of a space between the target and the second target, and placing a third target so that a sputtering surface is located facing the space; An opening at the head of the space with the second target, a substrate holding member for arranging the substrate facing the opening, and for generating a magnetic field in a direction perpendicular to the first and second sputtering surfaces. of A facing magnetron composite sputtering apparatus having a magnetic field generating means, wherein a main discharge formed on a sputtering surface of the first and second targets is a facing discharge and formed on a sputtering surface of the third target. An opposed magnetron composite sputtering apparatus, wherein the main discharge is a magnetron discharge. 2. The magnetic field generating means radially generates a magnetic field from the second target to the first target, and further includes a magnetic flux density perpendicular to the sputtering surfaces of the first and second targets and the third magnetic field. 2. The opposing magnetron composite sputtering apparatus according to claim 1, wherein said magnetic field generating means is capable of varying the intensity ratio of the magnetic flux density parallel to the sputtering surface of the target. 3. The distance from the upper ends of the first and second targets to the sputtering surface of the third target is at least 0.5 times the distance between the first and second targets. A facing magnetron composite sputtering apparatus as described in the above. 4. The magnetic field generating means is movable in a direction parallel to the sputter surfaces of the first and second targets, and a center position of the magnetic field generating portion is set to be higher than a facing magnetron composite sputter surface of the third target. The sputtering apparatus according to claim 1, which is located at an upper part. 5. The facing magnetron composite sputtering apparatus according to claim 1, wherein a plurality of sets of said first and second targets are arranged. 6. A cylindrically arranged second target is arranged concentrically outside a cylindrically arranged first target, and an outer periphery of a cylindrical shape formed by the first target is provided. A sputter surface, which forms a cylindrical inner peripheral surface formed by the second target, is opposed to a sputter surface, which forms a surface, by a predetermined distance, and a space between the first target and the second target is formed. Disposing a sputter surface of a third target at the bottom of the first target, opening the head of the space between the first target and the second target, and disposing a substrate facing the opening; And applying a magnetic field in a direction perpendicular to each of the second sputtering surfaces,
A thin film is formed on the substrate by generating an opposing discharge on the sputtering surfaces of the first and second targets and generating a magnetron discharge on the sputtering surface of the third target. Forming method. 7. The magnetic field generating means radially generates a magnetic field from the second target to the first target, and further includes a magnetic flux density perpendicular to the sputtering surfaces of the first and second targets and the third magnetic field. 7. The method according to claim 6, wherein the film is formed by changing the intensity ratio of the magnetic flux density parallel to the sputtering surface of the target. 8. The distance from the upper ends of the first and second targets to the sputtering surface of the third target is at least 0.5 times the distance between the first and second targets. The method for forming a thin film according to the above. 9. The magnetic field generating means is movable in a direction parallel to a sputtering surface of the first and second targets,
The thin film forming apparatus according to claim 6, wherein the thin film is formed by positioning a center position of the magnetic field generating portion above an opposed magnetron composite sputtering surface of the third target. 10. The thin film forming method according to claim 6, wherein a plurality of sets of said first and second targets are arranged.