JPS61120421A - Plasma treating apparatus - Google Patents

Abstract

PURPOSE:To enable a material to be treated to be introduced into or removed from a reaction chamber securely and smoothly, by providing a material table with a holding member which can be moved relatively in the opposite direction by the difference in stroke with the material table. CONSTITUTION:A chamber 2 is sealed at the lower end by a stage 6 and evacuated for performing a predetermined treatment. After completing the treatment, the pressure within the chamber 2 is returned to a normal pressure. A cam follower 16 is lowered and the stage 6 descends by its own weight. Since the stroke of the support shaft 11 of a chuck 10 is shorter than the stroke of the stage 6, the chuck 10 becomes elevated relatively to the stage 6 midway of the stroke. A photomask 14, which has been secured closely to the stage 6, is thereby lifted up by the chuck 10 and a space is produced between the lower face of the mask 14 and the upper face of the stage 6. This space permits the mask 14 to be supported stably from the lower side as well as to be exchanged securely and smoothly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a plasma processing technique, and particularly to a technique effective for use in ashing a photomask in the manufacture of semiconductor devices.

[Background Art] In the manufacturing of semiconductor devices, for example, in the process of forming photomask patterns, high accuracy is required in pattern dimensions in order to respond to the miniaturization and high integration of target semiconductor elements, and wavelength An electron beam photoresist exposed to a short electron beam is exposed to an electron beam.

In this case, after the development process, a small amount of electron beam resist, so-called electron beam resist scum, remains in the position where the photomask surface should originally be exposed, which causes a decrease in the dimensional accuracy of the pattern, and this electron beam resist scum must be removed. Therefore, it is conceivable to perform ashing processing using a plasma processing device.

That is, a photomask that has been developed is placed between electrodes in a reaction chamber of a plasma processing device, and harmful electron beam resist scum is removed by applying high-frequency power and supplying oxygen gas under a predetermined degree of vacuum. It removes it by oxidation.

In this case, in order to insert or take out the photomask to be processed into the reaction vessel, it is conceivable to use a holding arm that holds several points around the photomask. The inventor has discovered that because the holding arms are placed in close contact with each other, the holding arm cannot support the underside of the photomask, resulting in inconveniences such as an inability to reliably hold the photomask. .

The literature that describes plasma processing technology is "Electronic Materials J, November 1981 issue, special edition, published by Kogyo Research Association Co., Ltd., October 10, 1981, p.
There is P136.

[Object of the Invention] An object of the present invention is to provide a plasma processing technique that enables reliable and smooth insertion and removal of objects to be processed into and out of a reaction vessel.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

, [Summary of the Invention] A brief overview of typical inventions disclosed in this application is as follows.

That is, by providing the sample stand with a holding piece that can move in the opposite direction relative to the sample stand on which the object to be processed is positioned due to the stroke difference during the insertion and removal operations of the object to be processed into and out of the reaction vessel. We provide plasma processing technology that enables reliable and smooth exchange of objects by making it possible to stably hold the object from below with a structure that creates a gap between the object to be processed and the sample table surface. By doing so, the above objective is achieved.

[Embodiment] FIG. 1 is a sectional view of a plasma processing apparatus according to an embodiment of the present invention, and FIG. 2 is a sectional view showing the stage in a lowered state.

A chamber 2 (reaction container) is located on the base 1, and an electrode 3 is provided within the chamber 2.

The electrode 3 is provided with a gas supply port 4, and the chamber 2 is
The structure is such that oxygen gas 5 (processing fluid) flows into the chamber.

At a position facing the electrode 3, there is a stage 6 (which also serves as an electrode).
A sample stand) is removably provided and is supported by a pair of guide shafts 7.

The guide shafts are inserted into a pair of stage stoppers 8, respectively, and are guided by bearings 9 so as to be slidable in the vertical direction.

A chuck 10 (holding piece) is removably fitted in the center of the stage 6, and a shaft 11 that passes through the stage 6 is attached.
Supported by

A bearing 12 is provided in the penetrating portion of the shaft 11,
The shaft 11 is configured to be slidably guided in the vertical direction.

A chuck stopper 13 is provided below the shaft 11, and has a structure in which the lower end of the shaft 11 comes into contact.

In this case, the lower end of the shaft 11 and the chuck stopper 1
3, that is, the stroke of the chuck lO is configured to be smaller than the distance between the lower end surface of the stage 6 and the upper end of the stage stopper 8, that is, the stroke of the stage 6.

Therefore, when the stage 6 is lowered, the shaft 11 of the chuck lO, which is moved downward together with the stage 6, comes into contact with the chuck stopper 13, and the downward movement is stopped before the stage 6. As shown in FIG. 2, it is raised relative to the stage 6 and protrudes from the upper surface of the stage 6 by the above-mentioned stroke difference.

As a result, the photomask 14 positioned on the stage 6
(The object to be processed) is lifted from the top surface of the stage 6 by the chuck 10, and a transport mechanism (not shown), for example, is used to insert and take out the photomask 14.
The photomask 14 can be stably supported from below, and the photomask 14 can be handled smoothly and reliably.

Further, a spring 15 is provided between the shaft 11 and the chuck stopper 13, and the chuck 10 is mounted together with the stage 6.
When the chuck 10 is raised, the chuck 10 is pressed against the stage 6 by the tension of the spring 15, so that the airtightness between the chuck IO and the stage 6 is maintained.

A cam follower 16 is brought into contact with the lower part of the stage 6, and the stage 6 is raised and lowered at appropriate times by a cam mechanism (not shown).

An exhaust port 17 is formed in the base 1 and is connected to a vacuum pump (not shown) to evacuate the inside of the chamber 2 in a timely manner.

The electrode 3 and the stage 6 are connected to a high frequency power source 18,
The configuration is such that high frequency power is applied in a timely manner.

Next, the operation of this embodiment will be explained.

First, as shown in FIG. 1, the inside of the chamber 2, whose lower end is closed by the stage 6 and made airtight, is evacuated through the exhaust port 17 and brought to a predetermined degree of vacuum.

Next, oxygen gas 5 is supplied through the gas supply port 4 formed in the electrode 3, and high frequency power is applied between the electrode 3 and the stage 6, and the oxygen gas 5 is plasma dissociated and brought into an excited state. The electron beam resist scum remaining between the electron beam resist patterns on the photomask 14 is oxidized (
ashing), gasified, and exhausted outside the chamber 2.

After maintaining the above state for a predetermined period of time, the application of high frequency power is stopped, nitrogen gas is supplied from the gas supply port 4, and the inside of the chamber 2 is returned to normal pressure.

Next, the cam follower 16 is lowered, and the stage 6 is lowered by its own weight.

At this time, since the stroke of the shaft 11 supporting the chuck 10 is shorter than the stroke of the stage 6, the chuck 10 is raised relative to the stage 6 during its descent, and as shown in FIG. The photomask 14 that was in close contact with the top is held up by the chuck 10.

As a result, a gap is created between the lower part of the photomask 14 and the upper surface of the stage 6, making it possible to stably support the photomask 14 from below, allowing the replacement of the photomask 14 to be performed reliably and smoothly.

By repeating the above operations, a large number of photomasks 14 can be ashed reliably and smoothly.

[Effects] (1) A sample stand on which the object to be processed is placed and attached to or detached from the reaction vessel by being raised or lowered; A holding piece is provided that protrudes from the sample stand and attaches/detaches the workpiece to/from the sample stand by moving in the opposite direction relative to the sample stand. A gap is formed between the bottom of the object and the sample stage, allowing the exchange of objects to be processed using a transport mechanism that stably supports the object from below, ensuring reliable and smooth exchange of objects. be able to.

(2) As a result of T1), it becomes possible to automate the processing of the object to be processed.

(3) As a result of the above +11.121, the productivity of plasma processing equipment will be improved.

Although the invention made by the present inventor has been specifically explained above based on Examples, it goes without saying that the present invention is not limited to the Examples and can be modified in various ways without departing from the gist thereof. Nor.

For example, it is also possible to adopt a structure in which the stage on which the photomask is placed can be rotated.

[Field of Application] In the above description, the invention made by the present inventor was mainly applied to the field of application of photomasks, which is the background of the invention, but the invention is not limited to this, for example. , it is also possible to apply it to wafer plasma processing technology.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a plasma processing apparatus according to an embodiment of the present invention, and FIG. 2 is a sectional view showing the stage in a lowered state. 1...Base, 2...Chamber (reaction container), 3.
... Electrode, 4... Gas supply port, 5... Oxygen gas (processing fluid), 6... Stage (sample stand), 7... Guide shaft, 8... Stage stopper, 9...・Bearing, 10... Chuck (holding piece), 11... Shaft, 12... Bearing, 13... Chuck stopper 7, 14... Photomask (workpiece), 15...
...Spring, 16...Cam follower, 17...Exhaust port, 18...High frequency power supply. Figure 1

Claims (1)

[Scope of Claims] 1. A plasma processing apparatus that performs processing by supplying a processing fluid while applying high frequency power to a workpiece located between electrodes in a reaction vessel, the workpiece being A sample stand that is attached to or detached from the reaction vessel by being raised or lowered, and a sample stand that is removably fitted to this sample stand and moves in the opposite direction relative to the sample stand due to the stroke difference between the sample stand and the sample stand. 1. A plasma processing apparatus comprising: a holding piece for attaching and detaching an object to be processed to and from a sample stage. 2. The plasma processing apparatus according to claim 1, wherein the object to be processed is a photomask.