JPH05129239A - Processing apparatus - Google Patents

Abstract

PURPOSE:To make the concentration of a processing gas acting on an object to be processed uniform by providing a plurality of outlet ports in a processing chamber, and by providing each outlet port with an exhaust regulating means for adjusting the amount of exhaust gases so that the flow of exhaust gases can be regulated every outlet port. CONSTITUTION:A plasma apparatus 1 is chiefly constituted of a processing chamber 2, an upper electrode 3 and a lower electrode 4 which are arranged opposite to each other within the processing chamber 2, and a gas supply port 5 for introducing gas into the processing chamber 2. A plurality of exhaust pipes 6 are provided on the lower part of the chamber 2 for expelling exhaust gases from the inside of the processing chamber. Each exhaust pipe 6 is removably equipped with an exhaust regulating means 7 which can be set to a predetermined aperture ratio so that gas can be evenly expelled from the processing chamber 2. A processing gas is distributed along a plurality of supply paths by a gas supply port 10a of a gas supply plate 10, and discharged toward an electrode plate 31. Exhaust gases. resulting from plasma processing and an excess gas are expelled in the form of an even exhaust stream through the exhaust pipes 6 positioned at the four corners of the processing chamber 2 via the exhaust regulating means 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing apparatus for processing an object using a processing gas.

[0002]

2. Description of the Related Art Plasma processing such as plasma etching and reactive ion etching (RIE) is carried out as a method for forming a pattern on the surface of a semiconductor wafer, LCD substrate or the like, and as a method for removing resist after etching such as ashing or the like. Plasma processing is being performed. As a device for such plasma processing, there is a plasma device as shown in FIG.

In this plasma apparatus 20, an upper electrode 22 and a lower electrode 23 are arranged so as to face each other in a processing chamber 21, and a high frequency power source 24 is connected to the upper electrode 22 or the lower electrode 23, and a high frequency wave is applied between the electrodes. The voltage RF is applied. Further, the lower electrode 23 can be moved toward and away from the upper electrode 22, and the object to be processed 26 conveyed through the opening 25 is placed on the lower electrode 23 to set a predetermined distance from the upper electrode 22. A gas supply pipe 27 connected to a gas supply system for introducing a reaction gas such as O ₂ gas or CF ₄ gas into the processing chamber 21 is provided above the upper electrode 22, and a reaction according to the processing purpose is performed. Gas is introduced into the process chamber. A large number of small holes are formed in the upper electrode 22 and the processing gas diffusion plate 29, and the gas introduced from the gas supply pipe 27 is supplied between the electrodes. Further, an exhaust pipe 28 connected to a vacuum pump or the like (not shown) is connected to the lower periphery of the processing chamber 21 so as to exhaust the waste gas and the surplus gas in the processing chamber 21 and to maintain a predetermined degree of vacuum in the processing chamber 21. To maintain.

In such a plasma apparatus, the reaction gas supplied from the gas supply pipe 27 is radicalized or ionized by the discharge between the electrodes to perform plasma processing such as etching on the surface of the object to be processed 26 on the lower electrode 23. Excess gas and waste gas generated during processing are exhausted from the exhaust pipe 28.

[0005]

By the way, in recent years, semiconductor wafers and LCD substrates, which are objects to be processed, have become large in size, and in-plane uniformity of the processing is required. Therefore, in the above plasma processing apparatus, a processing gas diffusion plate 29 having a large number of small holes is provided between the gas supply pipe 27 and the upper electrode 22 so that the reaction gas is uniformly dispersed between the electrodes. There is.
However, even if the reaction gas is uniformly dispersed and supplied between the electrodes as described above, when the exhaust pipe 28 is provided at one location in the processing chamber 21, the gas flow is directed to the exhaust pipe 28. There is a problem that the gas concentration is different between the part of the object to be processed near the exhaust pipe 28 and the part far from the exhaust pipe 28, and the process becomes uneven.

[0006]

An object of the present invention is to solve such a conventional problem, and in an apparatus for treating an object to be treated while introducing a treatment gas into a treatment chamber and exhausting the treatment gas, It is an object of the present invention to provide a processing apparatus capable of individually adjusting the exhaust amount and thereby capable of uniformly processing an object to be processed. Another object of the present invention is to provide a processing device in which the exhaust flow rate can be adjusted extremely easily.

[0007]

A processing apparatus of the present invention that achieves the above object is an apparatus for processing an object to be processed installed in the processing chamber while introducing and exhausting a processing gas into the processing chamber. In addition, a plurality of exhaust ports are provided at the exhaust port, and exhaust control means for adjusting the exhaust amount is provided at the exhaust port.

[0008]

By exhausting gas from a plurality of exhaust ports, the flow of exhaust gas can be adjusted for each exhaust port, thereby making it possible to make the concentration of the processing gas acting on the object to be processed uniform, and Can be uniform. In addition, when the purpose of processing or the shape or size of the object to be processed changes, the exhaust volume of each exhaust port can be adjusted according to these changes, and an appropriate exhaust gas flow can always be obtained. it can.

[0009]

EXAMPLES The present invention will now be described with reference to glass substrates for LCDs (hereinafter,
An embodiment applied to an etching process of a substrate) will be described with reference to the drawings. The plasma device 1 of FIG.
It mainly comprises a processing chamber 2, an upper electrode 3 and a lower electrode 4 which are arranged facing each other in the processing chamber 2, and a gas supply port 5 for introducing a gas into the processing chamber 2. The processing chamber 2 is made of, for example, aluminum and has an alumina coating formed on its inner surface as a measure against corrosion. The upper portion of the processing chamber 2 can be opened and closed for reasons such as easy maintenance, and a gas supply port 5 for introducing a reaction gas into the processing chamber 2 is connected to the upper portion. The gas supply port 5 is
It is connected to a reaction gas source 54 via a supply pipe 51, a valve 52, and a filter 53, and a predetermined gas is supplied to the processing chamber 2 at a predetermined flow rate by controlling the valve 52. Depending on the purpose of processing, the reaction gas may be, for example, O ₂ gas for ashing, or S for etching.
F ₆ , CF ₄ , CCl ₄ or the like is used.

A plurality of exhaust pipes 6 for exhausting the gas in the processing chamber are connected to the lower peripheral portion of the processing chamber 2.
A plurality of exhaust pipes 6 are installed according to the shape of the object to be processed. The exhaust pipe 6 is connected to an exhaust mechanism (not shown), such as a rotary pump or a turbo molecular pump. Further, the exhaust pipe 6 is detachably attached with an exhaust adjusting means 7 capable of setting a predetermined opening ratio so that the gas in the processing chamber 2 is uniformly exhausted. The exhaust adjusting means 7 is made of a material such as aluminum that has been subjected to anticorrosion treatment, and is, for example, a cylindrical fixing member 7 attached to the exhaust pipe 6 as shown in FIG.
1 and a cylindrical flange 72 that is detachably fitted to the fixture 71. Fixture 71 and flange 72
Has a plurality of, for example, four openings 71a, 72a on its side surface.
Is provided, and the gas in the processing chamber 2 is exhausted to the exhaust system through the openings 71a and 72a. The displacement amount is adjusted by rotating the flange 72 and changing the degree of overlap between the opening 72a and the fixture 71a. This allows the flow of exhaust gas to be adjusted.

Exhaust adjusting means 7'shown in FIG. 3 shows another embodiment, and a flange 73 directly fitted to the exhaust pipe 6 is provided.
Consists of. The flange 73 is composed of a cylindrical portion installed on the exhaust pipe 6 and its upper surface, and an opening 73a is provided on the upper surface. The flange 73 has an opening 73a with a different diameter.
For example, for an exhaust pipe diameter of 65 mm, the opening diameter is 54
Several types of mm, 49 mm, 44 mm, etc. are prepared, and the flange 73 of the opening 73a having the optimum diameter is used according to the processing conditions. Since the flange 73 has a simple shape, it can be easily processed and the concentration of plasma can be avoided.

Further, the processing chamber 2 is provided with an opening 8 for loading and unloading a substrate to be processed, and an opening / closing mechanism (not shown) for opening / closing the opening 8 is provided on the outer surface of the side wall of the processing chamber 2. It is provided. By closing this opening / closing mechanism, the inside of the processing chamber 2 can be kept airtight. Load locks can be used if desired. The upper electrode 3 is fixed to the side surface of the processing chamber 2 via an insulating base 9. The insulating base 9 is made of quartz glass, ceramics or the like, and is fixed to the main body via an O-ring, and the upper electrode 3 is further fixed via the O-ring. Further, the upper electrode 3 is formed with a hole 3a for sending gas, and the gas supply port 5 is connected to the hole 3a.

Further, a gas supply plate 10 having a plurality of gas supply ports 10a is attached to the upper electrode 3 as a gas supply route means for branching the gas supply route and ejecting the gas to a plurality of locations in the processing chamber. The gas supply plate 10 has a gas passage connected to the hole 3a of the upper electrode 3 on one side, and a plurality of gas supply ports 10a provided on the other side respectively communicate with this gas passage. The gas supply plate 10 is made of, for example, aluminum and has a gas passage and a gas supply port 10a.
Has been surface treated to increase its corrosion resistance. The number and position of the gas supply ports 10a differ depending on the size and shape of the object to be processed and the gas used, and for example, 400 mm
When etching a rectangular glass substrate for LCD, one place at the center and four places between the center and four sides, total 5
In one place. Small baffles 11 for dispersing the spouting of gas are fitted into these gas supply ports 10a, respectively. The upper electrode 3 further includes a gas supply plate 10
A plurality of baffles 12, 13 of approximately the same shape as
And the electrode plate 31 is fixed. These baffles 11, 1
A large number of small holes 12a and 13a are arranged in four directions in 2 and 13, and the small holes of adjacent baffles do not overlap each other. In addition, the electrode plate 31 is also formed with a plurality of holes each having a minute diameter for allowing gas to pass therethrough. With such a configuration, the gas ejected from each gas supply port 10a can be supplied to the baffles 11, 12, 13 and the electrode plate 3.
As it passes through 1, it is more uniformly dispersed and supplied between the electrodes.

An insulating shield ring 32 is fixed to the outer periphery of the electrode plate 31. The shield ring 32 is made of quartz glass, ceramics, or the like, and acts so that the discharge between the electrodes is concentrated on a predetermined portion of the lower electrode 4. On the other hand, the lower electrode 4 is supported by the lifting mechanism 14,
It can be moved toward and away from the upper electrode 3 and is supported so as to maintain a predetermined distance from the upper electrode 3 during processing. Further, the lifting mechanism 14 includes a lower electrode 4
The upper electrode 3 (the electrode plate 3
It is configured to keep parallel to 1). Corresponding to this elevation, airtightness is maintained by a bellows 15 made of, for example, stainless steel. The lower electrode 4 is made of, for example, a flat plate made of aluminum, and the surface thereof is anodized. On the upper surface of the lower electrode 4, a rectangular substrate 16 which is an object to be processed is installed. To facilitate the installation of the substrate 16, the lower electrode 4 has lifter pins (not shown) that can be retracted on the surface. ) Is provided. Further, a focus member 17 for covering the lower electrode 4 is detachably provided in a portion other than the substrate installation portion of the lower electrode 4 in order to concentrate the discharge generated when the substrate 16 is plasma-treated on the surface of the substrate 16. There is. This focus member 17
Is a ring-shaped member having an L-shaped cross section with a thickness of, for example, 3 to 10 mm, and is made of a material having a sufficiently higher impedance than RF to the substrate 16, such as Teflon (trade name), quartz glass, or ceramics. ing. Since the focus member 17 is detachable, it can be easily replaced.

The upper electrode 3 and the lower electrode 4 are
One of them is connected to the high frequency power supply 18, and the other is grounded. For example, in the case of etching by radicals, the upper electrode 3 is connected to the high frequency power source 18 as shown in FIG. Further, in the case of the RIE mode in which etching is performed with ions, the lower electrode 4 is connected to the high frequency power supply 18. Further, the processing chamber 2 is controlled by a temperature control mechanism (not shown).
Inside, the upper electrode 3 and the lower electrode 4 are maintained at a predetermined temperature.

Next, the operation in such a configuration will be described. First, set the processing chamber 2 to a predetermined depressurized state,
The opening 8 formed in the side wall of the processing chamber 2 is opened, and the substrate 16 is loaded by a transfer mechanism (not shown) such as a handling arm. By setting the space outside the opening 8 as a load lock chamber, it is possible to maintain a reduced pressure in the processing chamber when the opening 8 is opened and closed. At this time, the lower electrode 4 is moved up and down by the lifting mechanism 14
At the lower position, the substrate 16 is supported by the lifter pins protruding from the surface. Then, the handling arm exits and the opening 8 is closed to make the processing chamber airtight. On the other hand, the lower electrode 4 is raised by the elevating mechanism 14 so that the substrate 16 is placed at a predetermined position on the lower electrode 4 and set at a predetermined distance from the upper electrode 3.

After that, RF power is applied between the upper electrode 3 and the lower electrode 4 to generate a discharge between the upper electrode 3 and the lower electrode 4. At the same time, a predetermined gas from the gas supply source 54, for example, O ₂ gas in the case of ashing, and SF ₆ , CF ₄ , CCl _{4 in the} case of etching, flows through the filter 53, the valve 52, and the supply pipe 51 at a predetermined flow rate. Through,
The gas is supplied to the gas supply plate 10 through the hole 3a of the upper electrode. The exhaust adjusting means 7 (7 ') selected according to the flow rate of the supplied gas is attached to the exhaust pipe 6, and exhaust is performed at a predetermined exhaust amount. On the other hand, the processing gas is divided into a plurality of supply paths by the gas supply port 10a of the gas supply plate 10 and is ejected toward the electrode plate 31. At this time, the gas is first diffused by each baffle 11 provided in the gas supply port 10a, further diffused by the baffles 12 and 13, and is extremely uniformly diffused in the surface direction of the electrode plate 3.
It is sent to the lower electrode 4 through one hole. This gas is turned into plasma by the discharge between the electrodes and generates radicals, for example, α-S deposited on the surface of the substrate 16.
The i film, SiNx film, Al film, etc. are selectively removed. Waste gas and surplus gas generated by this plasma treatment are
From the exhaust pipes 6 provided at the four corners of the processing chamber 2, a uniform exhaust flow is exhausted through the exhaust adjusting means 7 (7 ′).

In the above embodiments, an example of plasma processing using a rectangular glass substrate for LCD as an object to be processed has been described, but the processing apparatus of the present invention performs processing using semiconductor wafers and other gases. It goes without saying that it can be applied to the object to be processed.

[0019]

As is apparent from the above description, according to the processing apparatus of the present invention, by providing gas exhaust pipes at a plurality of places in the processing chamber, even a large object to be processed can have a uniform gas concentration over its entire surface. It can be formed and processed uniformly. Further, according to the plasma device of the present invention, by exchanging the exhaust gas adjusting means, it is possible to select and process the exhaust gas amount that enables the most uniform processing according to the purpose of the processing. Moreover, since it is detachable, maintenance is easy.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a plasma device to which the present invention is applied.

FIG. 2 is a diagram showing an embodiment of an exhaust adjusting means of the plasma device of FIG.

FIG. 3 is a diagram showing another embodiment of the exhaust control means of the plasma device of FIG.

FIG. 4 is a diagram showing a conventional plasma device.

[Explanation of symbols]

 1-Plasma device 2--Processing chamber 3--Upper electrode 4--Lower electrode 5-Gas supply port 6- ... Exhaust pipes 7, 7'71, 72, 73 ... Exhaust adjusting means 16 ...

Claims (1)

[Claims] 1. An apparatus for processing an object to be processed installed in the processing chamber while introducing and exhausting the processing gas into the processing chamber, wherein a plurality of exhaust ports are provided in the processing chamber and an exhaust amount is provided at the exhaust port. A processing device, characterized in that exhaust processing means for adjusting the temperature is provided.