JP4289916B2 - Thin film manufacturing method and thin film manufacturing apparatus - Google Patents

Description

【００３８】
上記表１からも明らかなように、２回の揺動幅変更の前と後とでは、不良率は大幅に改善されており、本発明がノジュールに起因する薄膜の欠陥の防止に効果的であることが分かる。
【００３９】
【発明の効果】
本発明の薄膜の製造方法および薄膜製造装置によれば、ターゲット下部に配置した磁石を揺動させながらスパッタリングを行う薄膜の製造方法において、磁石の揺動範囲を段階的に狭める揺動範囲変更を行うことにより、ノジュールの発生に起因する薄膜の欠陥を減少させることができ、品質の良い薄膜を効率よく製造することができる。
【図面の簡単な説明】
【図１】本発明の薄膜製造装置の一例を示す概略平面図である。
【図２】図１のＡ−Ａ´断面における概略断面図である。
【図３】本発明に用いられるターゲットの概略平面図である。
【符号の説明】
１ … ターゲット
６ … 磁石
７ … 磁石揺動範囲[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a thin film manufacturing method and a thin film manufacturing apparatus in which defects of a thin film due to generation of nodules are reduced by narrowing a swing range of a magnet in stages.
[0002]
[Prior art]
Thin films such as indium oxide, zinc oxide, and tin oxide have transparent conductivity, and are therefore widely used in various fields including light receiving devices such as optical sensors and photographing devices, touch panels, and solar cells. As a method for forming such a thin film on a base material, a vacuum deposition method, a sputtering method, a CVD (chemical vapor deposition method) and the like are well known, but a dense and excellent film can be formed. It is common to use sputtering without material restrictions.
[0003]
Various types of electrode structures have been proposed in conventional sputtering apparatuses, and among them, magnetron type electrode structures are most frequently used industrially. The reason is that the deposition rate is high and the productivity is high. There are various types of conventional magnetron-type electrodes. At present, a flat-plate magnetron cathode having a target having a planar shape is most useful industrially among the magnetron-type electrodes.
[0004]
Such a magnetron system includes a method of using a magnet fixed and a method of swinging the magnet. When sputtering is performed in a state where the magnet is fixed, the area of the erosion region on the target is almost the same as the magnetic field made of the magnet used. Therefore, when a wide erosion region is desired, the magnet to be used must be enlarged. In recent years, particularly for the production of liquid crystal display devices, there has been a demand for film formation with a uniform and uniform film thickness distribution on a large-area substrate. There was a need.
[0005]
On the other hand, when the magnet is swung, the erosion region on the target is expanded to the range of the magnetic field where the magnet swings. Therefore, a wider erosion region can be obtained with a small magnet, and the life of the target can be extended by changing the eroded portion.
[0006]
However, when sputtering is continued for a long time, some of the eroded target fine particles (hereinafter, these fine particles may be referred to as nodules) are the outer periphery of the erosion region of the target to be eroded. It adheres to non-erosion areas that are not. If sputtering is continued in this state, the nodules deposited in the non-erosion region peel off and adhere to the formed thin film, or the nodule comes into contact with the thin film and a part of the thin film is lost, resulting in a pinhole. Or other problems occur. In order to prevent these defects, accumulated nodules had to be removed, and production had to be stopped for cleaning despite the remaining life of the target.
[0007]
[Problems to be solved by the invention]
The present invention has been made in view of the above problems, and has as its main object to provide a thin film manufacturing method and a thin film manufacturing apparatus capable of efficiently manufacturing a thin film when forming a thin film by a sputtering method. To do.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, according to a first aspect of the present invention, in the thin film manufacturing method in which sputtering is performed while oscillating a magnet disposed under a target, the oscillating range of the magnet is gradually reduced. Provided is a thin film manufacturing method characterized by reducing thin film defects caused by nodule generation by changing the swing range.
[0009]
According to the present invention, by changing the swing range that gradually narrows the swing range of the magnet, by preventing the erosion near the non-erosion region where the nodule of the target adheres, the nodule peels off and becomes a thin film. It is possible to prevent the problem of causing a defect.
[0010]
In addition, by using the present invention, the time from the start of sputtering to the time when nodule removal cleaning becomes necessary is greatly extended, so the number of times production is stopped for cleaning is reduced, and the efficiency of thin film production is reduced. Can be greatly improved.
[0011]
In the invention described in claim 1, as described in claim 2, the swing range change amount of the magnet is preferably in the range of 5 to 25 mm at a time. If the amount of change of the swinging range that is narrowed at one time is smaller than the above range, the distance from the region where the nodules are attached may not be sufficient, and the effects of the present invention may not be fully exhibited. On the other hand, if it is larger than the above range, the area that can be eroded becomes narrow, and the efficiency may decrease.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to a method of manufacturing a thin film in which sputtering is performed while oscillating a magnet disposed under a target, and the thin film resulting from the generation of nodules is obtained by changing the oscillating range to gradually narrow the oscillating range of the magnet. The present invention relates to a thin film manufacturing method and a thin film manufacturing apparatus, which are characterized by reducing defects. Hereinafter, the thin film manufacturing method and thin film manufacturing apparatus of the present invention will be described in detail.
[0014]
(Method for manufacturing thin film)
The thin film manufacturing method according to the present invention reduces the inconvenience that nodules deposited in the non-erosion region of the target peel off, adhere to the thin film, and pinholes open on the thin film. The swing range is changed so that the swing range of the magnet is gradually reduced. By narrowing the swing range of the magnet and performing erosion in a region kept at a certain distance from the non-erosion region where nodules are accumulated, the above-mentioned problems can be greatly reduced. Hereinafter, the manufacturing method will be described.
[0015]
A. Change of Swing Range As shown in FIG. 3A, the target 1 used for sputtering of the present invention is provided on a backing plate 2. The surface of the target 1 can be divided into two regions: an erosion region 3 that is eroded during sputtering and a non-erosion region 4 that is located outside the erosion region 3 and is not eroded. The region where the magnet of the sputtering apparatus swings and is eroded is the erosion region 3, and nodules are likely to be deposited on the outer periphery of the erosion region 3, that is, the non-erosion region 4.
[0016]
Therefore, in the present invention, when nodules are deposited by performing sputtering for a certain period of time, as shown in FIG. 3B, the swing range is changed to narrow the erosion region 3, and a certain distance is maintained from the region where the nodules are deposited. To erode. By repeating this swing range change a plurality of times and narrowing the swing range in stages, the required number of nodule removal and cleaning can be greatly reduced, and a high-quality thin film can be efficiently manufactured. .
[0017]
The amount of change in the swing range of the magnet is within a range of 5 to 25 mm at a time, more preferably within a range of 10 to 20 mm, and particularly preferably within a range of 15 to 20 mm. If the swinging range narrowed at one time is smaller than the above range, the distance from the region where the nodules are attached may not be sufficient, and the effects of the present invention may not be fully exhibited. On the other hand, if it is larger than the above range, the area that can be eroded becomes narrow, and the efficiency may decrease.
[0018]
In addition, the time until the next swing range change varies greatly depending on the type of apparatus, sputtering conditions, target material, etc., but it depends on the amount of nodule generation and the rate of thin film defects. Generally, it is preferable to change the swing range every 50 to 150 hours, more preferably every 80 to 100 hours. If the time until the swing range is changed is shorter than the above range, the erosion region cannot be used effectively. If the time is longer than the above range, the vicinity of the region where nodules are accumulated erodes and the effect of the present invention is sufficiently obtained. This is because it may not be obtained.
[0019]
The change of the swing range may be changed only in the horizontal direction or only in the vertical direction of the erosion region, or in both directions.
[0020]
B. In addition, the target used in the production method of the present invention is not particularly limited, but generally, chromium (Cr) or ITO (Indium Tin Oxide) is preferably used.
[0021]
In order to prevent the backing plate from being eroded, a non-erosion region that is not eroded is provided near the outer periphery of the target. The non-erosion width is usually 5 to 15 mm, more preferably 5 to 8 mm. This is because if the width of the non-erosion region is smaller than the above range, the backing plate may be eroded, and if it is wider than the above range, the target may not be used effectively.
[0022]
(Thin film manufacturing equipment)
Next, a thin film manufacturing apparatus that enables the thin film manufacturing method of the present invention will be described.
[0023]
A. Configuration of Thin Film Manufacturing Apparatus FIGS. 1 and 2 show an example of a thin film manufacturing apparatus of the present invention. In the thin film manufacturing apparatus of this example, a flat magnet 6 is disposed on the back surface (backing plate 2 side) of the target 1 supported by the backing plate 2, and the glass substrate 5 is disposed so as to face the target 1. . A voltage is applied to the backing plate 2, and a magnetic field is generated on the surface of the target 1 by the magnet 6 disposed on the back surface of the backing plate 2. Due to the action of the magnetic field and the electric field, electrons cause a cyclonic motion, high-density plasma is generated in the target surface and in the magnetic field, and erosion progresses in a region surrounded by the magnetic field of the target. At that time, the magnet 6 is swung in the magnet swinging range 7 in order to advance the erosion in a wider region.
[0024]
In addition, the thin film manufacturing apparatus of this example is provided with a vacuum chamber 8 and an atmospheric area 9. The vacuum chamber 8 and the atmospheric area 9 include a vacuum chamber wall 10 and an insulator 11 on the vacuum chamber wall 10. Are separated by a backing plate 2 attached via In order to maintain the confidentiality of the vacuum chamber 8, the contact surface between the vacuum chamber wall 10 and the insulator 11 and the contact surface between the insulator 11 and the backing plate 2 are sealed.
[0025]
The glass substrate 5 is transported in the direction of the arrow 12 in the drawing in the vacuum chamber 8, and the fine particles sputtered and spattered from the target 1 during transport are deposited on the glass substrate 5 to form a thin film on the glass substrate 5. Is done. An arrow 13 indicates a region where the glass substrate is conveyed, that is, a film formation region. Since the magnet swing range 7 is set wider than the film formation region, even if the magnet swing range 7 is somewhat narrowed, the film formation region is not narrowed.
[0026]
The target 1 is attached to the backing plate 2, and the target 1 is attached to the apparatus via the backing plate 2. Since the backing plate functions as an electrode during sputtering, the backing plate is preferably made of a material such as copper having good conductivity or an alloy thereof. Further, the backing plate 2 and the vacuum chamber wall 10 are insulated by an insulator 11.
[0027]
The target 1 may be composed of a single flat plate or may be divided into a plurality of pieces. Further, as described above, Cr, ITO or the like is preferably used as the material of the target 1.
[0028]
B. Magnet Swing Method In the thin film manufacturing apparatus of the present invention, the magnet is swung so as to draw a square 14 as shown in FIG. The swinging method is not particularly limited as long as it can stably move the magnet at a desired speed, and examples thereof include a method of controlling a ball screw with an inverter and a method of using an air cylinder. Further, the method of swinging the magnet in the vertical direction and the method of swinging in the horizontal direction may be the same method or different methods.
[0029]
C. Means for Changing Magnet Swing Range The thin film manufacturing apparatus of the present invention has a changing means capable of changing the swing range of the magnet in the thin film manufacturing apparatus that performs sputtering while swinging the magnet disposed below the target. And The swing range can be changed by limiting a part of the motion of the magnet swung by the method described in the above-mentioned “B. Magnet Swing Method”. The specific change means varies depending on the method of swinging the magnet, but the method of shortening the drive range of the magnet swinging device and shortening the moving range, and detecting the position of the magnet or swinging device with a sensor and swinging Examples include a method of stopping the driving of the device, a method of physically limiting the movement of the magnet by attaching a stopper to the swing device.
[0030]
The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.
[0031]
【Example】
The following examples further illustrate the invention.
[0032]
Using a thin film manufacturing apparatus having changing means capable of changing the swing range of the magnet, the swing width was changed twice during the target use period (6 to 7 days) to form a film.
[0033]
Using an ITO target with a width of 300 mm, the oscillating width of the magnet of the thin film manufacturing apparatus is 290 mm at the start of the experiment, 270 mm after the first change after 90 hours, and the second time after 120 hours. After the change, the film was formed with a setting of 250 mm. The production was terminated after 150 hours, which is the life of the target.
[0034]
In this embodiment, the magnet was swung using a linear guide and an air cylinder in the vertical direction, and using a linear guide, a ball screw, and an inverter motor in the horizontal direction. Note that the swing range was changed only in the left-right direction.
[0035]
When the magnet that moves to the left (right) at 100% speed reaches the deceleration start sensor at the right (left) end, the deceleration start timer works and starts deceleration when the timer expires. Then, the cycle was repeated until the speed reached 0% and then accelerated to -100%. The swing range was changed by changing the operation time of the timer in three stages. The thin film manufacturing apparatus used was SDP-s1550VT manufactured by ULVAC.
[0036]
Table 1 shows the ratio (%) of thin films that were defective due to dents among the manufactured thin films. Here, the dent scar refers to a scratch having a shape that has been obtained as a result of a collision of a foreign object with a certain energy.
[0037]
[Table 1]

[0038]
As apparent from Table 1 above, the defect rate is greatly improved before and after the change of the oscillation width twice, and the present invention is effective in preventing defects in the thin film caused by nodules. I understand that there is.
[0039]
【The invention's effect】
According to the thin film manufacturing method and thin film manufacturing apparatus of the present invention, in the thin film manufacturing method in which sputtering is performed while swinging the magnet disposed below the target, the swing range change that gradually narrows the swing range of the magnet is performed. By doing so, defects in the thin film due to the generation of nodules can be reduced, and a high-quality thin film can be efficiently manufactured.
[Brief description of the drawings]
FIG. 1 is a schematic plan view showing an example of a thin film production apparatus of the present invention.
FIG. 2 is a schematic cross-sectional view taken along the line AA ′ of FIG.
FIG. 3 is a schematic plan view of a target used in the present invention.
[Explanation of symbols]
1 ... Target 6 ... Magnet 7 ... Magnet swing range

Claims (2)

  In the thin film manufacturing method that performs sputtering while swinging the magnet placed under the target, by changing the swing range that gradually narrows the swing range of the magnet, thin film defects caused by the generation of nodules are reduced. A method for producing a thin film, comprising:   The method of manufacturing a thin film according to claim 1, wherein the swing range change amount of the magnet is within a range of 5 to 20 mm at a time.

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