JPH0841638A - Sputtering device - Google Patents

Abstract

PURPOSE:To three-dimensionally recognize the shape of a target and to accurately measure the consumption of the target at the time of injecting a spotlight into the target by inclining a mirror provided between a light source and the target to scan the target with the spotlight. CONSTITUTION:A spotlight from a light source 14 is reflected by a mirror 16 and made incident on a target 10. The incident light is reflected by the target 10 and made incident on one point on a two-dimensional position detector 18 (PSD) corresponding to the position of the incident light and the shape of the target 10. The coordinate data corresponding to the position of the light detected by the PSD 18 are outputted and transmitted to a processor 20. The mirror 16 is moved to move the light incident on the target 10 in the x- and y-axis directions, and plural two-dimensional data corresponding to the shape of the target 10 are obtained. The data at the different places of the target 10 are combined to obtain the three-dimensional data. The three-dimensional data are calibrated to obtain the consumption of the target 10 at the respective positions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputtering apparatus for forming a thin film, and more particularly to a sputtering apparatus having a detection function capable of accurately measuring a target consumption amount and accurately determining a target life.

[0002]

2. Description of the Related Art A sputtering apparatus used for forming a thin film in a manufacturing process of a semiconductor device or the like bombards a target made of a material of a film to be deposited with ions of an inert gas such as argon, and a molecule sputtered from the target. Is deposited on the sample. For this reason, the target gradually decreases as it is used, so it is necessary to keep track of the state of the target and replace it before it completely disappears.

However, when observing the surface condition of the target for each treatment, the efficiency of the film forming process is greatly deteriorated. Therefore, the target of the sputtering apparatus is usually replaced by the number of formed films or the accumulated power of the discharge power during sputtering and the target. It was done by investigating the relationship with the consumption amount in advance and predicting and managing the replacement time of the target. Further, as another management method, a light source and a one-dimensional CCD are provided in the sputtering apparatus, spot light emitted from the light source is irradiated onto the target, and the reflected light is detected by the one-dimensional CCD to detect a one-dimensional CC.
There is a method of observing the state of the target by the position of the spot light incident on D. That is, as shown in FIG. 5, when the target 10 is not reduced at all, the target 1
The spot light reflected by 0 is A of the one-dimensional CCD 28.
It is incident on a point, but when the target 10 decreases, B
Incident on a point. Therefore, since the consumption amount of the target 10 can be predicted from the distance between the points A and B, the target 10 can be replaced before the target 10 is exhausted.

[0004]

However, in the above-described conventional sputtering apparatus that controls the consumption of the target 10 by the number of sputters and the integrated power of the discharge power at the time of sputtering, the surface condition of the target 10 is not directly observed. Since it is a judgment, there is a problem that the state of the target 10 cannot be accurately known when the relationship between the number of deposited films or the integrated power and the consumption amount of the target 10 changes due to the difference in the sputtering conditions. .

Further, since the reduction of the target 10 changes depending on the sputtering conditions and the like, and it is not always easy to consume the same place, the state of a part of the target is observed by using the light source and the one-dimensional CCD 28 and the target 10 is observed. In the conventional sputtering apparatus that manages the consumption of the target, there is a problem that the information does not always reflect the consumption of the target 10.

Further, when the target 10 is completely replaced due to the change in the sputtering conditions in this way, and the target 10 is completely lost, the backing plate 26 supporting the target 10 and the bonding material of the target 10 are supported. However, there is a problem in that impurities are mixed into the formed thin film and the element characteristics of the semiconductor device deteriorate, for example, since the sputtering is performed.

The object of the present invention is to recognize the target consumption three-dimensionally, so that the target replacement time can be accurately determined even if the target is deviated due to the difference in sputtering conditions. It is to provide a sputtering device capable of performing the above.

[0008]

The above object is to provide a light source for emitting spot-like light and a light source on the optical axis of the light source in a sputtering apparatus for sputtering a target made of a material to be deposited to form a thin film on a substrate. A mirror for reflecting the spot-shaped light to enter the target and moving the spot-shaped light incident position freely; and detecting the spot-shaped light reflected by the target. And a measuring device that measures the amount of consumption of the target based on the position of the spot-shaped light detected by the detector.

Further, in a sputtering apparatus for sputtering a target made of a material to be deposited to form a thin film on a substrate, a light source which emits slit light and a light which is emitted from the light source and reflected by the target are detected. The present invention is achieved by a sputtering apparatus including a detector and a measuring device that measures the amount of consumption of the target based on the position and shape of the light detected by the detector.

Further, in the above sputtering apparatus, the linear light is provided on the optical axis of the light source, reflects the linear light to enter the target, and the position where the linear light enters is freely moved. It is achieved by a sputtering device characterized in that it further has a mirror. Further, in the above-described sputtering apparatus, the slit light is achieved by a slit light formed through a slit having a linear opening.

In the above sputtering apparatus, the slit light is a slit light formed through a cylindrical lens that collects light on a straight line. Further, the above-mentioned sputtering apparatus is achieved by further comprising display means for three-dimensionally displaying the measured consumption amount of the target corresponding to the position of the target.

[0012]

According to the present invention, in a sputtering device having a measuring device for irradiating a target with light emitted from a light source and measuring the amount of consumption of the target by the reflected light from the target, the spot light emitted from the light source is applied to the target. When entering, a mirror is provided between the light source and the target, and the spot light can be scanned on the target by tilting the mirror, so that the shape of the target can be obtained as three-dimensional information.

Further, by calculating the consumption of the target using the three-dimensional information obtained in this way, the target can be exchanged even if the target is deviated due to the difference in the sputtering conditions. The time can be accurately determined. Further, since it is possible to accurately determine the replacement time of the target in this manner, the target can be used up to the limit.

Further, on the basis of the above measurement results, the sputtering apparatus can be interlocked when the thickness of the target becomes insufficient, so that sputtering will not occur in the state where the target is absent, thus forming It is possible to prevent impurities from being mixed into the thin film.
Furthermore, since the light emitted from the light source is converted into linear light and incident on the target, two-dimensional data corresponding to the shape of the target can be obtained from the light cutting line formed on the target.

Further, since the linear light is used, three-dimensional information of the target shape can be obtained by scanning the target surface in only one direction. Therefore, the consumption of the target is faster than the case of using the spot light. It can be calculated.

[0016]

EXAMPLE A sputtering apparatus according to a first example of the present invention will be described with reference to FIGS. FIG. 1 is a schematic view of a sputtering apparatus according to this embodiment, FIG. 2 is an explanatory view of the principle of the sputtering apparatus according to this embodiment, and FIG. 3 is an example of measuring a target shape according to this embodiment.

Target 10 made of the material of the deposited film
Are arranged so as to face the sample 12 forming a thin film. A light source 14 that emits a spot light is arranged near the target 10. On the optical axis of the light source 14, the light source 1
A mirror 16 for reflecting the spot light emitted from the laser beam 4 to enter the target is arranged. Mirror 16
It has a movable mechanism (not shown) that can adjust the angle along two orthogonal axes so that the reflected light can scan the target 10. On the optical axis of the spot light that enters the target 10 and is reflected by the target 10,
A two-dimensional position detecting element (PSD) 18 that converts a position on which light is applied into coordinates and outputs the coordinates is arranged. PSD18
A processing device 20 for processing the coordinate data output from the PSD 18 is connected to the. Furthermore, the processing device 20
A display device 30 for displaying the data processed by the processing device 20 is connected to the.

Next, the operation of the sputtering apparatus according to this embodiment will be described. The spot light emitted from the light source 14 is reflected by the mirror 16 and enters the target 10. The light incident on the target 10 is reflected by the target 10 and is incident on a certain point on the PSD 18 corresponding to the position of the incident light and the shape of the target 10. PSD18
Depending on the position of the light detected by, the PSD 18 outputs coordinate data corresponding to the position, and the processing device 20 processes the data.

Here, the light incident on the target 10 is
For example, when scanning in the Y-axis direction as shown in FIG.
The light detected by the PSD 18 draws a locus corresponding to the position of the light incident on the target 10 and the shape of the target 10. If the target 10 has a recess, the position of the light incident on the target is X as shown in FIG.
Since it shifts in the negative direction along the axis, PSD18
The locus of the light detected at is as shown in FIG. At this time, the X-axis direction indicates the depth direction of the target 10 and the Y-axis indicates the direction along the surface of the target 10.

In this way, the coordinates of the light at each position are stored using the PSD while the target 1
By scanning the light incident on 0 in the Y-axis direction, two-dimensional data corresponding to the target shape can be obtained. Next, the same measurement is repeated while moving the mirror 16 in the X-axis direction at predetermined intervals, and a plurality of two-dimensional data as shown in FIG. 3 are obtained. Since these plural two-dimensional data reflect the target shape in different places, the target 10 can be combined by combining them.
It is possible to obtain three-dimensional data corresponding to the shape.

By calibrating the three-dimensional data obtained by the PSD 18 in this way, the consumption amount at each position of the target 10 can be obtained.
In addition, if the consumption amount of the target 10 is measured each time by the above measurement, and if the thickness of the target 10 is not sufficient even in a part, an alarm is generated and the sputter device is interlocked. It is possible to prevent spattering.

As described above, according to this embodiment, when the spot light emitted from the light source is incident on the target, a mirror is provided between the light source and the target, and the tilt of the mirror causes the spot light to be emitted on the target. Since the scanning is enabled, the shape of the target can be changed from outside the sputter device to 3
It can be obtained as dimensional information. Further, by calculating the consumption amount at each position of the target 10 using the three-dimensional information obtained in this way, the target can be deviated even when the target is reduced due to the difference in the sputtering conditions. It is possible to accurately determine the replacement time.

Further, since the target replacement time can be accurately determined, the target can be used up to the limit. Also, based on the above measurement results, it is possible to interlock the sputtering device when the target thickness becomes insufficient, so that sputtering will not occur without the target and the thin film to be formed It is possible to prevent impurities from being mixed.

The three-dimensional information obtained by this embodiment may be displayed three-dimensionally. For example, based on the coordinate data output from the PSD, the shape of the target surface may be expressed by a wire frame drawn by a line and output to the display device 30. Next, the second aspect of the present invention
The sputtering apparatus according to this embodiment will be described with reference to FIG.

FIG. 4 is a schematic view of the sputtering apparatus according to this embodiment. The sputtering apparatus according to the present embodiment is based on the same principle as that of the first embodiment, but is characterized in that linear light is incident on the target instead of spot light. That is, the target 10 made of the material of the film to be deposited is arranged so as to face the sample 12 forming the thin film. In the vicinity of the target 10, the light source 1
4 and a slit 22 for converting the light emitted from the light source 14 into a linear light. On the optical axis of the light source 14, a mirror 16 for reflecting linear light to enter the target 10 is arranged. The mirror 16 has a movable mechanism (not shown) whose angle can be adjusted along an axis orthogonal to the direction of the slit 22 so that the reflected slit light can scan the entire surface of the target 10. A two-dimensional camera (CCD camera or the like) 24 is arranged on the optical axis of the slit light incident on the target 10 and reflected by the target 10 to convert the position where the light hits into coordinates and output the coordinates. The two-dimensional camera 24 includes a processing device 20 that processes coordinate data output from the two-dimensional camera 24.
Is connected. Further, a display device 30 that displays the data processed by the processing device 20 is connected to the processing device 20.

Next, the operation of the sputtering apparatus according to this embodiment will be described. The light emitted from the light source 14 is slit 22.
After being linearized by, it is reflected by the mirror 16,
It is incident on the target 10. This makes target 1
On 0, a light cutting line is formed by the incident light. The light cutting line formed by the incidence of the linear light is equal to the locus when the spot light is scanned in the first embodiment. Then, the light section line formed on the target 10 is detected by the two-dimensional camera 24. Two-dimensional camera 24
Since the shape of the light section line detected at 1 corresponds to the shape of the target 10, the two-dimensional data corresponding to the shape of the target 10 is obtained from the coordinate data of the light section line detected by the two-dimensional camera 24. be able to.

Then, as in the first embodiment, the mirror 1
The same measurement is repeated while moving 6 in the X-axis direction at predetermined intervals to obtain a plurality of two-dimensional data (FIG. 3). Since the plurality of two-dimensional data reflects the target shape at different places, it is possible to obtain three-dimensional data corresponding to the shape of the target 10 by combining them.

As described above, according to the present embodiment, since the linear light is used to enter the target, the light cutting line formed on the target corresponds to the shape of the target.
Dimensional data can be obtained. Further, by scanning the target surface in only one direction, the three-dimensional information of the target shape can be obtained, so that the consumption amount of the target can be calculated faster than when using spot light.

In this embodiment, the linear light is formed by using the slit, but it is only necessary that the light cutting line can be formed on the target. Therefore, the linear light may be formed by another method. For example, light may be condensed using a cylindrical lens and then incident on the target.

[0030]

As described above, according to the present invention, in a sputtering apparatus having a measuring device that irradiates a target with light emitted from a light source and measures the consumption of the target by the reflected light from the target, the sputtering device emits light. When the spot light is incident on the target, a mirror is provided between the light source and the target, and the tilt of the mirror allows the spot light to scan the target. It can be obtained as three-dimensional information.

Further, by calculating the consumption amount of the target 10 by using the three-dimensional information obtained in this way, even if the reduction of the target is biased due to the difference in the sputtering conditions, the target It is possible to accurately determine the replacement time. Further, since the target replacement time can be accurately determined, the target can be used up to the limit.

Further, on the basis of the above measurement results, when the thickness of the target becomes insufficient, the sputter device can be interlocked, so that sputtering will not occur in the state where the target is absent, thus forming It is possible to prevent impurities from being mixed into the thin film.
Furthermore, since the light emitted from the light source is converted into linear light and incident on the target, two-dimensional data corresponding to the shape of the target can be obtained from the light cutting line formed on the target.

Further, since the linear light is used, three-dimensional information of the target shape can be obtained by scanning the target surface in only one direction. Therefore, the consumption of the target is faster than the case of using the spot light. It can be calculated.

[Brief description of drawings]

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

FIG. 2 is an explanatory view of the principle of the sputtering apparatus according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a measurement example of a target shape according to the first embodiment of the present invention.

FIG. 4 is a schematic diagram of a sputtering apparatus according to a second embodiment of the present invention.

FIG. 5 is a diagram showing a target shape inspection device in a conventional sputtering device.

[Explanation of symbols]

 10 ... Target 12 ... Sample 14 ... Light source 16 ... Mirror 18 ... Two-dimensional position detecting element (PSD) 20 ... Processing device 22 ... Slit 24 ... Two-dimensional camera 26 ... Backing plate 28 ... One-dimensional CCD 30 ... Display device

Claims (6)

[Claims] 1. A sputtering apparatus for forming a thin film on a substrate by sputtering a target made of a material to be deposited, a light source for emitting spot-shaped light, and a spot-shaped light source provided on the optical axis of the light source. A mirror that reflects light and is incident on the target, and freely moves the incident position of the spot-shaped light, a detector that detects the spot-shaped light reflected by the target, and the detector And a measuring device for measuring the consumption amount of the target based on the position of the spot-shaped light detected by the sputtering apparatus. 2. A sputtering apparatus for sputtering a target made of a material to be deposited to form a thin film on a substrate, and detecting a light source that emits slit light and light emitted from the light source and reflected by the target. A detector, and the position and shape of the light detected by the detector,
A sputtering apparatus, comprising: a measuring instrument for measuring the consumption of the target. 3. The sputtering apparatus according to claim 2, wherein the linear light is provided on the optical axis of the light source, reflects the linear light to enter the target, and sets a position where the linear light enters. A sputtering apparatus further comprising a mirror that moves freely. 4. The sputtering apparatus according to claim 2, wherein the slit light is slit light formed through a slit having a linear opening. 5. The sputtering apparatus according to claim 2, wherein the slit light is slit light formed through a cylindrical lens that collects light on a straight line. 6. The sputtering apparatus according to claim 1, further comprising display means for three-dimensionally displaying the measured consumption amount of the target corresponding to the position of the target. Sputtering equipment.