JP2003034857A - Sputtering apparatus and method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sputtering apparatus capable of raising an operation rate of the apparatus, by arranging a means for removing a film forming material deposited on a deposition shield and a substrate mask, and by extending a repairing cycle for the sputtering apparatus, and to provide a method. SOLUTION: The sputtering apparatus consisting of a vacuum chamber capable of keeping vacuum, a substrate holding mount in the vacuum chamber, for mounting a substrate to be treated with plasma, a target arranged so as to face the substrate holding mount, a power source for applying negative voltage to the target, and a gas feeding/exhausting device for exhausting gas while feeding it into the vacuum chamber, is characterized by having the deposition shield for preventing deposition of vapor, on the internal surface of the vacuum chamber, arranging a magnetic field generation means on the back face of the deposition shield, and installing a movement mechanism in the magnetic field generation means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputtering apparatus and method used for manufacturing semiconductor devices and liquid crystal devices, and is characterized by means for preventing dust generated in a vacuum chamber.

[0002]

2. Description of the Related Art In recent years, electronic devices such as semiconductors have been rapidly miniaturized, and high precision processing is required. In such a fine processing technique, processing using a plasma processing method is generally used.
A dry etching method, a plasma CVD method, a sputtering method or the like is used.

Among the plasma processing methods described above,
In particular, the sputtering method will be described as an example. FIG. 5 is a schematic diagram of a conventional sputtering apparatus.

The sputtering apparatus usually has a bipolar discharge tube structure consisting of a pair of cathode and anode, the cathode corresponds to the target 1, and the anode corresponds to the substrate holding table 3 on which the substrate 2 is placed. Hereinafter, a specific operation procedure will be described.

First, argon gas is introduced from the gas supply device 5 into the vacuum chamber 4 and, at the same time, the gas exhaust device 6 exhausts the argon gas. Further, by supplying a negative DC or AC voltage to the target 1 from the power supply 7 while controlling the inside of the vacuum chamber 4 to a predetermined pressure, the argon gas becomes a plasma state and is positively ionized. At this time, the positive ions collide with the surface of the target 1 one after another, and sputter particles are ejected from the surface of the target 1. The sputtered particles that jumped out,
A thin film made of sputtered particles is formed by depositing on the substrate 2 placed on the substrate holder 3. At that time, target 1
If a magnetron magnet 8 for generating magnetic lines of force that closes on the surface of the target 1 is arranged on the back surface of the target 1, a higher density plasma can be generated and the film forming process of the substrate 2 can be effectively performed.

At this time, many sputtered particles are not limited to only the surface of the substrate 2 but also diffused to the inner wall surface of the vacuum chamber 4 and the like. In, if there is a region that does not require the film formation process,
Measures are taken such as providing a substrate mask 10 on the side of the substrate 2 facing the target 1.

[0007]

However, as the film forming process described above is performed, sputtered particles (target material) are deposited on the deposition-preventing plate 9 and the like arranged near the exhaust port in the vacuum chamber 4. As a result, the exhaust characteristics in the vacuum chamber 4 may be deteriorated and the deposited film may be peeled off to generate dust. Further, when the film forming process is performed by the method described above, the deposition-preventing plate 9 arranged in the vacuum chamber 4 does not mean that the deposited film is evenly attached, and a specific deposition-preventing plate 9 is often used.
Often concentrated in. Due to such a problem, repair such as replacement of the deposition-prevention plate 9 is required earlier than expected in advance. At this time, since the interior of the vacuum chamber 4 is temporarily returned to atmospheric pressure, sputtering This is one of the factors that lower the operating rate of the equipment.

The present invention solves the above-mentioned problems of the prior art by providing means for removing the film forming material adhering to the deposition preventive plate and the substrate mask, and increasing the repair cycle of the sputtering apparatus, thereby making An object of the present invention is to provide a sputtering apparatus and method capable of increasing the operating rate.

[0009]

In order to achieve the above object, the sputtering apparatus and method of the present invention are provided with a magnetic field generating means on the back surface of a deposition-prevention plate or substrate mask arranged in a vacuum chamber. By controlling the magnetic field strength and line shape of magnetic force generated on the surface of the deposition preventive plate or the substrate mask, ions are drawn from the plasma generated in the vacuum chamber and collide with the surface of the deposition preventive plate, so that they are generated during the process. By removing the kimono, it is possible to reduce the deposition rate of the adhered matter that adheres to the surface of the adhesion preventing plate. As a result, the maintainability of the sputtering device can be improved.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIG. 1 shows the overall structure of a sputtering apparatus. This apparatus comprises a target 1, a substrate holder 3, a vacuum chamber 4, a gas introduction device 5, a gas exhaust device 6, a power supply 7, a magnetron magnet 8, an adhesion prevention plate 9, a substrate mask 10 and a magnetic field generation means 11. .

A specific operation procedure for forming a film on the surface of the substrate 2 using the above-described sputtering apparatus will be described below.

First, a sputtering gas is introduced into the vacuum chamber 4 from the gas supply device 5. Although an inert gas such as argon gas or Xe is generally used as the sputtering gas, this embodiment will be described particularly in the case of introducing the argon gas. Then, while introducing the argon gas into the vacuum chamber 4, the gas is exhausted by the gas exhaust device 6. Further, by controlling the interior of the vacuum chamber 4 to a predetermined pressure, by supplying a DC or AC negative voltage from the power source 7 to the target 1, the argon gas becomes a plasma state and is positively ionized (Ar ⁺ /
Argon ion). Most of the argon ions are drawn into the target 1 and knock out the particles of the material of the target 1, and the knocked-out particles are transferred to the substrate 2.
The film forming process is performed on the surface of the substrate 2 by adhering to.

At this time, a part of the particles adheres not only to the surface of the substrate 2 but also to the deposition preventing plate 9 arranged on the surface of the inner wall of the vacuum chamber 4 or the like. When the film forming process is performed in such a situation, some of the argon ions are removed by the action and effect of the magnetic field generating means 12 arranged on the back surface of the deposition preventive plate 9 or the substrate mask 10. The deposited film of 10 will be re-sputtered and scraped.

The film component thus re-sputtered is diffused in the vacuum chamber 4 and redeposited on the other deposition preventive plate 9 and the substrate mask 10 to prevent the deposition from being concentrated on a part thereof. , The deposition preventive plate 9 and the substrate mask 10 installed in the vacuum chamber 4
Can be widely attached to.

As a specific example, a case of forming an optical disk substrate for performing a film forming process on a substrate 2 having a diameter of 120 mm by using a target 1 having a diameter of 203 mm will be mentioned. Normally, a protective film is surrounded around the deposition preventive plate 9, but ZnS.SiO ₂ is often used as the material of the protective film. When the deposition-preventing plate 9 in which ZnS / SiO ₂ is surrounded as a protective film is used to apply a power of about 3 kW to the target 1 to perform the film-forming process of the phase-change optical disk, 5000 to 6000 The film begins to peel off from the adhesion-preventing plate 9 at the time when the treatment is carried out to some extent, and the peeled film adheres to the disk surface. Therefore, when the magnet 11 is arranged on the back surface of the deposition-inhibitory plate 9 as in this embodiment, the deposition-inhibition plate 9
It is possible to reduce the deposition rate of the film adhering to, and as a result of performing the film forming process according to the above-described operation procedure, it is possible to process 10,000 or more sheets.

The place where the magnet 11 is arranged is at the attachment plate 9
It may be arranged on all surfaces of the back surface or the back surface of the substrate mask 10, but it is preferably not arranged near the target 1 so as not to affect the shape of the magnetic force lines generated near the target 1 by the magnetron magnet.

From the above, by arranging the magnet on the back surface of the deposition-inhibitory plate, the film adhered to a part of the deposition-inhibitory plate can be diffused. In the conventional technique, about 5000 to 6000 sheets are spread. At the time of performing the film forming process of 1), the phenomenon of the film peeling from the deposition preventive plate was observed.
It is possible to process 0000 or more sheets, it is possible to reduce the deposition rate of adhesion to the deposition preventive plate, and it is possible to prolong the replacement period of the deposition preventive plate.

(Second Embodiment) FIG. 2 is a schematic view of a sputtering apparatus according to this embodiment.

The present embodiment is characterized in that the magnet 11 is provided with a moving mechanism 12 and the magnet 11 is moved as necessary to enable effective control.

A specific operation procedure using the moving mechanism 12 will be described below.

Guided by the lines of magnetic force generated by the magnet 11,
The argon ions are accelerated by the self-bias and collide with the deposition preventive plate 9 and the substrate mask 10 one after another. At this time,
It is difficult to control the rate at which the deposited film peels off due to the sputtering phenomenon independently of the process conditions such as the target 1 input power. Therefore, depending on the configuration of the sputtering apparatus, the target material, and the exhaust system capacity, when the deposition rate cannot be sufficiently reduced, or on the contrary, excessive sputtering is performed, and the deposition prevention plate 9 and the substrate mask 10 themselves are scraped. There is a risk that

The moving mechanism 12 can be realized by driving an air cylinder or a ball screw. When the magnet 11 is brought closer to the deposition preventive plate 9 or the substrate mask 10, the magnetic field strength on the surface of the deposition preventive plate 9 or the substrate mask 10 is increased, and the effect of increasing the amount of drawing in argon ions is obtained. When the amount of drawn argon ions increases, the film deposition rate on the surfaces of the deposition preventive plate 9 and the substrate mask 10 can be reduced.

On the contrary, the magnet 11 is attached to the deposition preventive plate 9 and the substrate mask 1.
If the distance is far from 0, the magnetic field strength on the surfaces of the deposition preventive plate 9 and the substrate mask 10 can be weakened, and the effect of reducing the amount of argon ion attraction can be obtained. When the amount of drawn argon ions decreases, the film deposition rate on the surfaces of the deposition preventive plate 9 and the substrate mask 10 can be increased.

As described above, a moving mechanism is provided on the magnets arranged on the back surface of the deposition-inhibiting plate or the substrate mask, and the magnets are moved as necessary, so that the film attached to the deposition-inhibiting plate or the substrate mask. It is possible to effectively control the amount of deposition.

(Third Embodiment) In the second embodiment,
In addition to disposing the magnet 11 on the back surface of the deposition-inhibitory plate 9, a method for moving the magnet 11 (moving mechanism 12) is provided to diffuse the film attached to the deposition-inhibition plate 9. The present embodiment is characterized in that elemental analysis means 13 for measuring the amount of film deposited on the deposition preventive plate 9 is provided, and means for driving the magnet 11 by the moving mechanism 12 is provided based on the result.

FIG. 3 is a schematic diagram of a sputtering apparatus according to this embodiment, which has an element analysis means 13 and a control means 14 in addition to the apparatus configurations of the first and second embodiments. The elemental analysis means 13 performs elemental analysis of the plasma generated in the vacuum chamber 4. A plasma emission monitor may be used for elemental analysis.

Specifically, the emission intensity of plasma is monitored and the emission intensity is analyzed to identify the elemental component, and an elemental component signal is sent to the control means 14 as necessary. The control means 14 analyzes and processes the signal,
The position of the magnet 11 is controlled by driving the moving mechanism 12 as needed.

For example, stainless steel is used for the deposition prevention plate 9,
The case where aluminum is used for the target 1 will be described. During film formation, elements generated in plasma generated in the vacuum chamber 4 are analyzed. When aluminum element is detected, the moving mechanism 12 is driven to drive the magnet 11 The attachment plate 9
Approach to. On the other hand, when the stainless element is detected in the plasma, the magnet 11 is moved away from the deposition preventive plate 9, and the driving of the magnet 11 is stopped when the stainless element disappears.

As described above, in general, when the components of the target 1 are detected in the plasma, the magnet 11 is attached to the anti-adhesion plate 9.
When the component of the deposition preventive plate 9 is detected, it is effective to move the magnet 11 away from the deposition preventive plate 9 and stop the driving when the component of the deposition preventive plate 9 disappears.

The magnets 11 are arranged by the method described above to prevent the attachment plate 9.
From the time of new product to the time of replacement. After the deposition-prevention plate 9 has been replaced, if it is necessary to perform the film forming process in the same situation before the replacement, the elements generated in the plasma are analyzed in real time. Instead, the magnet 11 may be arranged at a fixed position.

In this embodiment, the method of driving the magnet 11 arranged on the back surface of the deposition preventive plate 9 by the moving mechanism 12 has been described. However, the magnet 11 is arranged on the back surface of the substrate mask 10 and the moving mechanism 12 is arranged. May be driven.

Further, as shown in FIG. 4, the ion beam source 15 is arranged in the vacuum chamber 4 and the deposition preventive plate 9 and the substrate mask 10 are periodically irradiated with the ion beam, so that the deposition amount is extremely large. Means for peeling off the film in the part may be used.

As described above, the magnet arranged on the back surface of the deposition preventive plate or the substrate mask is provided with the element analysis means and the control means in addition to the moving mechanism to analyze the elements generated in the plasma. It is possible to effectively control the amount of film deposited on the deposition preventing plate by moving the film. as a result,
It is possible to increase the replacement cycle of the deposition preventive plate and the substrate mask. Further, in the method of irradiating with an ion beam, it is not necessary to return the inside of the vacuum chamber to the atmosphere, so that it is possible to significantly shorten the apparatus stop time.

In the first to third embodiments, the sputtering apparatus has been explained as an example, but the plasma CV is used.
The embodiment can be applied to a plasma processing apparatus such as a D apparatus or a dry etching apparatus.

[0035]

According to the sputtering apparatus and method of the present invention, a magnetic field generating means is provided on the back surface of the deposition preventive plate or the substrate mask, and the means for driving the magnetic field generating means is used to provide the deposition preventive plate or the substrate mask. It is possible to reduce the deposition rate on the substrate and prolong the replacement cycle of the deposition preventive plate. At that time, if an element of plasma generated in the vacuum chamber is analyzed and the element is appropriately driven according to the analyzed element, a better effect can be produced.

[Brief description of drawings]

FIG. 1 is a schematic diagram illustrating a sputtering apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram illustrating a sputtering device according to a second embodiment of the present invention.

FIG. 3 is a schematic diagram illustrating a sputtering apparatus according to a third embodiment of the present invention.

FIG. 4 is a schematic diagram illustrating a sputtering device according to a third embodiment of the present invention.

FIG. 5 is a schematic view of a sputtering device in a conventional example.

[Explanation of symbols]

1 target 2 substrates 3 substrate holder 4 vacuum tank 5 gas supply device 6 gas exhaust system 7 power supply 8 magnetron magnets 9 Defense plate 10 Substrate mask 11 magnets 12 Moving mechanism 13 Elemental analysis means 14 Control means 15 Ion beam source

Claims (7)

[Claims] 1. A vacuum chamber capable of maintaining a vacuum,
A substrate holder in the vacuum chamber, on which a substrate to be processed by plasma is placed, a target arranged so as to face the substrate holder, and a power supply for applying a negative voltage to the target, A sputtering device comprising a gas supply / exhaust device for supplying gas into a vacuum chamber while exhausting the gas, wherein an adhesion preventive plate is arranged on an inner wall surface of the vacuum chamber, and a magnetic field generating means is arranged on a back surface of the adhesion preventive plate. And sputtering equipment. 2. The sputtering apparatus according to claim 1, wherein the magnetic field generating means has a moving mechanism. 3. A substrate mask which covers at least a part of the substrate is provided around the substrate holder, and a magnetic field generating means is provided on the back surface of the substrate mask.
The sputtering apparatus described. 4. An element analysis means for analyzing an element in plasma is provided, and based on an analysis result by the element analysis means,
The sputtering apparatus according to any one of claims 1 to 3, wherein the magnetic field generating means is controlled. 5. The sputtering apparatus according to claim 1, wherein an ion beam source is provided at a position facing the substrate mask. 6. A gas is evacuated while being supplied to the vacuum chamber, plasma is generated in the vacuum chamber while controlling the pressure to a predetermined level, and a negative voltage is applied to the target to face the target. A sputtering method for treating a substrate placed on a substrate holder, wherein the magnetic field on the back surface of the deposition preventive plate is controlled while analyzing the elements in the plasma. 7. The sputtering method according to claim 6, wherein the magnetic field on the back surface of the substrate mask covering at least a part of the substrate is controlled while analyzing the elements in the plasma.