JP2003313664A - Film-forming apparatus using plasma - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a film-forming apparatus using a plasma which is equipped with a measurement system which measures a plasma emission intensity distribution near the surface of a substrate, calculates a film thickness distribution from the measured plasma emission intensity distribution and enables controlling of the plasma emission intensity distribution based on the calculated value. <P>SOLUTION: The film-forming apparatus is equipped with the measurement system composed of an optical part which transmits only an inherent emission wavelength band emitted from the plasma, an imaging system and an image- processing system. From the measured plasma emission intensity distribution, the measurement system calculates the film thickness distribution based on a predetermined correlation between the plasma emission intensity distribution and the film thickness distribution and enables controlling of the plasma emission intensity distribution based on the calculated value. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a film forming apparatus capable of controlling plasma emission intensity distribution and film thickness distribution based on a film thickness distribution calculated from measured values of plasma emission intensity distribution.

[0002]

2. Description of the Related Art In the industrial field, plasma is used in various places, and since it is possible to form a good quality thin film, it has become an essential field mainly in the field of thin films and surface treatments. The film formation using plasma includes an ion plating method, which is an evaporation method performed in plasma. Ions in plasma play an important role in film formation. In addition, plasma CVD (Chemical Vapor)
The Deposition method is a method of depositing one or more gases as a raw material of a target thin film, applying an electric power between the electrodes to discharge, and decomposing and depositing a thin film on a substrate by a reaction action. Further, the sputtering method is a method in which accelerated ions are collided with a material that is a source of a film to be formed, which is called a target, and the material is knocked out to deposit a thin film on a substrate. One of the important things in film formation using these plasmas is that the plasma is maintained uniformly and the film thickness is good. In particular, when the area is increased, the film thickness distribution becomes a serious problem, which greatly affects the quality and yield.

Conventionally, as a method of measuring plasma during film formation, an optical emission method (optical emission method) is used.
n Spectroscopy) and is widely used as a relatively simple measurement method. Plasma is a state in which gas molecules, ions and electrons are mixed, and ionization and excitation are performed by collisions of electrons, atoms and molecules in plasma, and there are luminescent species generated by various reactions. .

The emission species has a unique wavelength spectrum. For example, when oxygen gas is introduced to generate oxygen plasma, a spectrum peculiar to oxygen appears at 777 nm. As described above, the emission analysis method is a method of measuring a spectrum emitted from a luminescent species in plasma by using an optical system such as a spectroscope. As a result, the film formation is stabilized by examining the excited species in the plasma and monitoring the variation.

However, although it is possible to identify the excited species and grasp the behavior by this method, for example, the emission intensity distribution of plasma near the surface of the substrate is monitored and measured, and the film thickness distribution is measured. It was difficult.
In addition, it is often unclear which part of the plasma is being measured due to its characteristics. For example, in-plane plasma uniformity measurement, which is important in film formation of large-sized large-sized substrates, It was very difficult to measure the in-plane film thickness distribution.

[0006]

The present invention has been made in view of the above problems, and for example, measures the emission intensity distribution of plasma near the surface of the substrate or the emission intensity distribution for each wavelength band. An object of the present invention is to provide a film forming apparatus using plasma capable of performing. Further, from the measured plasma emission intensity distribution, the film thickness distribution is calculated based on the correlation between the predetermined plasma emission intensity distribution and the film thickness distribution of the deposited film, and the plasma emission intensity distribution is controlled by the calculated value. An object of the present invention is to provide a film forming apparatus using plasma, which is equipped with a measuring device that enables the film formation.

[0007]

The present invention provides at least the following:
It is composed of an optical component, a photographing device, and an image processing device, which pass only a peculiar emission wavelength band emitted from plasma.
A film forming apparatus using plasma, characterized in that a measuring apparatus for measuring a plasma emission intensity distribution is provided.

Further, according to the present invention, in the film forming apparatus using the plasma according to the above-mentioned invention, the measuring apparatus divides the measured plasma light emission intensity distribution into a predetermined plasma light emission intensity distribution and a film thickness distribution of the deposited film. A film forming apparatus using plasma, wherein the film thickness distribution is calculated based on the correlation, and the plasma emission intensity distribution can be controlled by the calculated value.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below. FIG. 1 is an explanatory diagram showing the configuration of an embodiment of a film forming apparatus using plasma according to the present invention. As shown in FIG. 1, the film forming apparatus using plasma according to the present invention is
The film forming apparatus (10) is equipped with a measuring device (20). The film forming apparatus (10) includes a chamber (11), a plasma control device (12) and a gas control device (13), and the chamber (11) includes an electrode (14), a target (15), a substrate (16), A measuring glass (17) is provided. The measuring device (20) includes a bandpass filter (21), a CCD camera (22), a camera control device (23), an image display monitor (24), and a recording device (2).
5) and an image processing device (26).

The chamber (11) shown in FIG. 1 is a plan view for explaining the internal structure thereof. Figure 2
It is sectional drawing in the AA line of FIG. 1 and 2
As shown in FIG. 2, the film forming apparatus using plasma according to the present invention measures the intensity distribution of plasma emission (P) generated between the substrate (16) and the target (15) by the measuring glass (17),
The CCD camera (2
The image is taken by 2), monitored by the image display monitor (24), and measured by the image processing device (26).

Further, in the film forming apparatus using plasma according to the present invention, the film thickness distribution is calculated based on the correlation between a predetermined plasma light emission intensity distribution and the film thickness distribution of the deposited film from the measured plasma light emission intensity distribution. And the calculated value is fed back to the plasma control device (12) and the gas control device (13) to control the plasma emission intensity distribution, that is, the film thickness distribution.

For measurement, plasma is used to scan a CCD camera (2
It is desirable to cover with a material coated with a light absorbing agent or the like so that unnecessary disturbance light does not enter during the period up to 2). It is desirable that the CCD camera has an adjustable exposure time. This is to optimize the image according to the amount of light passing through the optical component. The measured image data passes through the camera control device (23), is displayed on the image display monitor (24), is recorded in the recording device (25), and is recorded in the image processing device (2).
6), the film thickness distribution is calculated based on the predetermined correlation between the plasma emission intensity distribution and the film thickness distribution of the deposited film, and the calculated value is calculated as the plasma control device (12) and the gas control device. The plasma emission intensity distribution is controlled by feeding back to (13). That is, the film thickness distribution is controlled.

The film-forming apparatus is a single-wafer type in which the substrate is changed every time, a continuous film-forming type, a roll-up film-forming type in which a plastic film or the like is used as a substrate, and a plasma-using film forming apparatus. Any type will do as long as it is available. Further, a film forming method using plasma includes an ion plating method, a plasma CVD method, a sputtering method and the like, and is not particularly limited.

Further, there is a so-called bandpass filter as an optical component capable of passing only a specific wavelength band,
Any wavelength can be selected for this, and the half width is not limited. For example, an optical component is used in which plasma is measured by an emission analysis method, and the wavelength obtained from the result is used as a specific wavelength band. The attachment measurement may be performed one by one or two or more types may be overlapped.

The photographing device can be selected according to the amount of light passing through the bandpass filter and the wavelength, and the form thereof may be any device capable of photographing, such as a CCD camera or an image storage CCD camera. Furthermore, the image processing apparatus is not limited to, for example, capturing image data in a personal computer and measuring plasma emission intensity distribution and calculating film thickness distribution, and various image processing and analysis are possible. The image processing can be performed during the measurement or after the measurement.

[0016]

[Examples] <Example 1> Plasma emission intensity distribution and film thickness distribution of titanium were measured by a DC sputtering method using a titanium target. Argon was used as the sputtering gas. To measure the emission intensity distribution of titanium, a plasma emission of only titanium was selected and measured using a bandpass filter of 500 nm which is an emission spectrum of titanium atoms.
A bandpass filter having a half width of 5 nm was used. The substrate is glass, the film thickness distribution is measured after film formation,
It was compared with the emission intensity distribution of plasma. The results of plasma emission intensity distribution and film thickness distribution are shown in FIG.

[0017]

According to the present invention, for example, a film forming apparatus using plasma is provided with a measuring device for photographing and monitoring the emission intensity distribution of plasma in the vicinity of the surface of the substrate, and for measuring with an image processing device. Therefore, it is not unclear which part of the plasma is being measured, and a plasma that can measure the plasma emission intensity distribution near the surface of the substrate and the emission intensity distribution for each wavelength band can be used. This is the film forming apparatus used.

Further, according to the present invention, in the film forming apparatus using the above plasma, from the measured plasma emission intensity distribution,
The film thickness distribution is calculated based on the correlation between the predetermined plasma light emission intensity distribution and the film thickness distribution of the deposited film, and the plasma light emission intensity distribution can be controlled by the calculated value. It is possible to control the thickness distribution.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing a configuration of an example of a film forming apparatus using plasma according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3A is an explanatory diagram of plasma emission intensity distribution in Example 1. (B) is an explanatory view of a film thickness distribution in Example 1.

[Explanation of symbols]

10 ... Film forming apparatus 11 ... Chamber 12 ... Plasma control device 13 ... Gas control device 14 ... Electrode 15 ... Target 16 ... Substrate 17 ... Glass for measurement 20 ... Measuring device 21: Bandpass filter 22 ... CCD camera 23 ... Camera control device 24 ... Image display monitor 25 ... Recording device 26 ... Image processing device P ... Plasma

Claims (2)

[Claims] 1. A measuring device for measuring a plasma emission intensity distribution, which comprises at least an optical component for passing only a peculiar emission wavelength band emitted from plasma, a photographing device and an image processing device. A film forming apparatus using plasma. 2. The film thickness distribution is calculated by the measuring device from the measured plasma light emission intensity distribution based on a correlation between a predetermined plasma light emission intensity distribution and a film thickness distribution of a deposited film,
The film forming apparatus using plasma according to claim 1, wherein the film forming apparatus is a measuring apparatus capable of controlling the plasma emission intensity distribution based on the calculated value.