JPH10172794A - Plasma processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a top space of a cap body and simplify an auxiliary mechanism for opening and closing the cap body so that connection and disconnection of high-frequency power is automatically performed during opening and closing of the cap body by transferring a high-frequency matching device to a main body side of a processing container. SOLUTION: A high-frequency matching device 8 for impedance matching to be mounted or a vacuum processing container 1 is mounted on a main body 1a side instead of a cap body 1b. By mounting the high-frequency matching device 8 on the main body 1a side, when the cap body 1b is opened and closed, there is generated a need for disconnecting or connecting a power supply line 9 for supplying high-frequency power from the high-frequency matching device 8 to a high-frequency electrode 4, however, the power supply line 9 is connected by a high-frequency power connector 11 to do this. A multiple-point contact is employed for the connector 11 such that the power supply line 9 is inserted into or removed from the opposite multiple-point contacts with opening and closing of the cap body 1b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma processing apparatus such as a semiconductor manufacturing apparatus for processing an object to be processed such as a semiconductor wafer or a glass substrate using plasma, and more particularly, to the installation of a high-frequency matching device for matching impedance. Regarding what improved the place.

[0002]

2. Description of the Related Art FIG. 4 is a diagram showing the basic configuration of a conventional plasma processing apparatus.
Is an exhaust system (vacuum pump), 4 is a high-frequency electrode for plasma generation provided in the vacuum processing vessel 1, and 5 is a high-frequency electrode 4
A workpiece mounting table 6 is disposed opposite to the processing board 6, and a workpiece substrate (semiconductor wafer, glass substrate, or the like) mounted on the mounting table 5. The high frequency power is supplied to the high frequency oscillator 7.
Is introduced into the high-frequency electrode 4 via the high-frequency matching device 8 to generate a plasma 10 between the high-frequency electrode 4 and the work table 5. At this time, the high-frequency matching device 8 performs impedance matching such that the input resistance of the high-frequency electrode 4 is apparently 50Ω when viewed from the output of the high-frequency oscillator 7.

Here, the high-frequency power matched by the high-frequency matching device 8 is introduced into the high-frequency electrode 4 through a feed line 9 formed of a copper plate or rod. It is desirable that the configuration be as simple as possible.

What is desired to shorten the path of the power supply line 9 is that the power supply line 9 itself is a resistor having a real resistance (R) component as a center, and the power consumption in the power supply line 9 is minimized. To do that.

Further, it is desired that the path of the power supply line 9 be simply formed because an induction resistance (L) component formed by the electromagnetic shield tube 15 and other conductive materials disposed around the power supply line 9 and other components, and the like. This is to prevent generation of a large number of uncertain resistance components such as a capacitance resistance (C) component and a contact resistance caused by a tight contact between a plurality of constituent metals when the feeder line 9 is not a single structure.

[0006]

In the case where the electrode supplying the high-frequency power is the upper electrode of the upper and lower electrodes, considering the above description, as shown in FIG.
Is installed in the upper space of the outer shell of the lid of the vacuum processing container 1.

At present, the shape of a single-wafer vacuum processing vessel 1 for processing a small substrate to be processed, such as a semiconductor wafer, has a bottom area (300 × 350 mm) × height of about 400 mm.
Considering that the high-frequency matching device 8 has a small installation area (350 × 300 mm) × about 150 mm in height even if the shape of the high-frequency matching device 8 is small, the high-frequency matching device 8 reduces the installation area of the upper part of the lid of the vacuum processing vessel 1 by about 86%. By occupying and mounting the high-frequency matching unit 8, the height of the entire processing module is increased by about 50%.

The lid of the vacuum processing vessel 1 and the high-frequency electrode 4 are connected to a high-frequency power supply line, a gas introduction system, a cooling water (or constant temperature water) system, a heater power line, a measurement port, and the like. These arrangements are greatly limited by the presence of the high-frequency matching device 8. Usually, the cooling water supply / drainage system, the high-frequency power supply line, the control signal line, and the like are also connected to the main body of the high-frequency matching device 8, so that the connection portion should be removed when opening and closing the cover, or the overload should not be caused in advance. It is necessary to make room for the routing route.

By the way, in order to open and close the lid of the vacuum processing container 1, a one-sided lid using a rotating tool (hinge) on one side or one corner of the lid is usually adopted. At this time, the space in which the high-frequency matching device 8 mounted on the lid moves when the lid is opened / closed is considerably larger than in a case where the high-frequency matching device 8 is not provided. That is, the vacuum processing container 1
If there is a pipe or other equipment on the upper side, it is necessary to secure a predetermined space above the vacuum processing vessel 1 so that the space required for opening and closing the lid including the high-frequency matching device 8 does not interfere with them.

[0010] Considering the safety aspects for workers,
The high-frequency matching device 8 usually weighs about 10 to 15 kg. When such a heavy object is placed on the upper portion of the lid of the vacuum processing container 1, the weight of the lid and the high-frequency matching device 3 is reduced when the lid is opened and closed. In addition, a mechanism for assisting the opening and closing force is required. Further, at the time of maintenance work in which the lid is opened and a part of the operator's hand or body enters the vacuum processing container 1, a lid opening / closing assisting mechanism for holding the weight of the lid and the high-frequency matching device 8 is required.

In consideration of the above description, if the installation location of the high-frequency matching device 8 can be moved from the upper portion of the lid of the vacuum processing vessel 1 to another location, the utility related to the high-frequency matching device 8 when opening and closing the lid. (Wiring, water system, etc.)
There is no need to consider the routing of the lid, and there is room for the layout of utilities around the lid (gas introduction system, wiring, water system, drive air system, etc.) Can be simplified.

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and an object of the present invention is to move the high-frequency matching device to the main body side of the processing container, thereby opening a space above the lid and simplifying the auxiliary mechanism for opening and closing the lid. It is another object of the present invention to provide a plasma processing apparatus that can connect and disconnect a high-frequency power supply line in order to eliminate an obstacle caused by opening and closing the lid.

[0013]

According to the present invention, an electrode is provided on a lid of a processing vessel composed of a main body and a lid, and high-frequency power is supplied to the electrode from a high-frequency matching device via a power supply line. In a plasma processing apparatus that generates plasma and processes an object to be processed in a processing container, the high-frequency matching device is attached to a main body side of the processing container, and the high-frequency matching device is connected to the electrode so that a lid can be opened and closed. The power supply line for supplying high-frequency power is connected and disconnected by a connector.

When closing the lid, a power supply line is connected by connecting a connector, and high-frequency power is supplied to the electrodes from the high-frequency matching device. When opening the lid, the connector is cut off to cut the power supply line, and the high-frequency matching device and the electrode are separated. Therefore, when opening and closing the lid, it is not necessary to consider the routing of the power supply line and the like related to the high-frequency matching device. In addition, since it is not necessary to attach a high-frequency matching device to the lid, a margin is also provided for the lid, and the opening and closing assist mechanism for the lid is simplified as the weight of the lid is reduced.

In particular, a structure for connecting and disconnecting the power supply line by a connector is provided by providing a multipoint contact opposed to the connector and opening and closing the lid between the opposed multipoint contacts. When the power supply line is configured to be inserted and removed, connection and disconnection of the power supply line are automatically performed with opening and closing of the lid. Further, by using the multipoint contact, a reliable and electrically sufficient contact can be obtained.

If the length of the power supply line from the high-frequency matching device to the electrode is suppressed to １ ／ or less of the oscillation wavelength of the high-frequency power, the voltage component at the electrode serving as the power supply point becomes zero. Therefore, a voltage component necessary for plasma generation can be secured.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a plasma processing apparatus according to the present invention will be described below. FIG. 1 shows a first embodiment. In FIG. 1, parts corresponding to those in FIG. 4 are denoted by the same reference numerals.

The vacuum processing vessel 1 is composed of a main body 1a and a lid 1b serving as an upper lid for covering the upper opening, and is configured to open and close the upper opening of the main body 1a. The high-frequency matching device 8 for matching the impedance during discharge is installed on the side of the main body 1a, not on the lid 1b. Accordingly, the power supply line 9 extending along the outer shell of the lid 1b is covered with the electromagnetic shield tube 15.

By installing a high-frequency matching device 8 on the side of the main body 1a, a space above the outer shell of the lid is opened, an auxiliary mechanism for opening and closing the lid is simplified, and supply of high-frequency power is synchronized with opening and closing of the lid. It also enables connection and disconnection of electric wires.

High-frequency power is introduced from a high-frequency oscillator 7 to a high-frequency electrode 4 provided on the lid 1b by a feeder line 9 via a high-frequency matching device 8 provided on the side of the main body 1a. Then, the plasma 10 is generated between the workpiece mounting table 5 and the gap. At this time, the feeding line 9 is configured to be longer than the desirable path length described above, and this length is さ が (= 5.53 m) of the oscillation wavelength λ of the high frequency oscillator (13.56 MHz). In the following case, a standing wave does not stand on the path, so that the voltage component does not become 0 at the connection point (feed point) between the feed line 9 and the high-frequency electrode 4, and the voltage required for plasma generation Ingredients can be secured.

However, since the heat loss increases as the actual resistance (R) increases with the extension of the power supply line 9, the input efficiency of the high-frequency power applied to the high-frequency electrode 4 cannot be reduced. However, experiments have shown that when a copper plate having a sufficient thickness and width is used for the power supply line 9, there is almost no heat generation due to the extension of the power supply line 9, and a necessary and sufficient high-frequency power can be supplied. That is, if the required amount can be ensured while taking into account the input efficiency of the high-frequency power, the feeder line 9 can be substantially extended.

However, the problem that the high-frequency matching device 8 is installed on the side of the vacuum processing container 1 is that a part of the power supply line 9 must be cut off when the cover is opened. This problem has been solved by using a high-frequency power connector 11 as shown in FIG. That is, the high-frequency power connector 11 is composed of a conductor base plate 12 in which multipoint contacts 13 formed of comb-shaped spring contacts are vertically arranged inside.
Are arranged so as to face each other, and both are fixed by two shaft pins 14 so that the power supply line 9 is sandwiched between the facing multipoint contacts 13.

The high-frequency power connector 11 is a multipoint contact 1
3 itself has a springy elasticity, and the shaft pin 14 for fixing the conductive base plates 12 also has a bending force, so that the feeder line 9 can be inserted and removed, and the feeder line 9 can be inserted. , The comb-shaped spring contacts of the multipoint contactor 13 independently press-contact the surface of the feeder line 9, so that the contact area (multipoint contact) far exceeds the tight contact by ordinary screwing. Although it depends on the structure and the number of the child, it is said that it is 10 times or more of the tight contact).

The high-frequency power connector 11 is used at a division point of the power supply line 9 to be cut when the lid is opened, and one end of the divided power supply line 9 is connected to the high-frequency power connector 11.
If the other end is free and fixed to the lid 1b side, the power supply line 9 can be automatically cut or connected in synchronization with opening and closing of the lid 1b.

As described above, when high-frequency power is applied to the upper electrode, the conventional restriction that the high-frequency matching device is installed above the lid is released, and the degree of freedom in the installation location of the high-frequency matching device increases. Thus, the degree of freedom in the structural design of the processing module including the vacuum processing container can be increased. In addition, since the high-frequency matching device is independent of the lid, the disconnection / connection of the power supply line caused by opening and closing of the lid can be electrically performed by applying the high-frequency power connector incorporating the multipoint contact. Sufficient contact can be secured.

FIG. 2 shows a second embodiment in which the present embodiment is further advanced. The high-frequency matching device 8 is provided below the vacuum processing container 1, and the high-frequency power generated from the high-frequency oscillator 7 is used as the high-frequency power of the high-frequency power passed through the high-frequency matching device 3 to the inside of the side wall of the vacuum processing container 1. Transmission line 16
The power is applied to the upper high-frequency electrode 4 through the power supply line 9 to generate a plasma 10 between the high-frequency electrode 4 and the work table 5. Naturally, the high-frequency power connector 11 is used in the middle of the power supply line 9 so that the cover 1b can be opened and closed. In this case, the greatest advantage is that the transmission path 16 for high-frequency power has a function as an electromagnetic shield tube by forming the transmission path 16 through a hole inside the side wall of the vacuum processing vessel 1. Since it is a plasma processing tank, the entire outer wall of the vacuum processing container 1 is a sufficiently grounded electromagnetic shield container, and the transmission line 16 formed inside the wall is more electromagnetically shielded than the conventional external electromagnetic shield tube 15. Can be sealed. In addition, by installing the high-frequency matching device 3 below the vacuum processing container 1, the footprint of the entire processing module can be reduced, and the appearance of the processing module can be simplified.

In the above embodiment, the case where the lid is the upper lid has been described, but the present invention can also be applied to the case where the lid is the lower lid.

[0028]

According to the present invention, by moving the high-frequency matching device to the main body side of the processing container, the conventional restriction is released, the degree of freedom in design can be improved, and the auxiliary mechanism for opening and closing the lid is also provided. Can be simplified. In addition, since the high-frequency power supply line is automatically connected and disconnected when the lid is opened and closed, workability and safety are significantly improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a plasma processing apparatus according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a plasma processing apparatus according to a second embodiment of the present invention.

3A and 3B are principle structural diagrams of the high-frequency power connector according to the present embodiment, in which FIG. 3A is a side view and FIG. 3B is a perspective view of a conductor base plate constituting the high-frequency power connector.

FIG. 4 is a sectional view of a conventional plasma processing apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vacuum processing container 4 High frequency electrode 6 Workpiece 7 High frequency oscillator 8 High frequency matching device 9 Power supply line 10 Plasma 11 High frequency power connector

Claims (3)

[Claims] An electrode is provided on a lid of a processing container composed of a main body and a lid, and high-frequency power is supplied to the electrode from a high-frequency matching device via a power supply line to generate plasma, thereby generating a plasma. In the plasma processing apparatus for processing an object to be processed, the high-frequency matching device is attached to a main body of the processing container, and a power supply line for supplying high-frequency power from the high-frequency matching device to the electrode so that a lid can be opened and closed. A plasma processing apparatus having a structure of connecting and disconnecting with a connector. 2. A structure for connecting and disconnecting the power supply line by a connector, wherein a connector is provided with opposing multipoint contacts, and a lid is opened and closed between the opposing multipoint contacts. The plasma processing apparatus according to claim 1, wherein the power supply line is configured to be inserted and removed. 3. The plasma processing apparatus according to claim 1, wherein a length of a power supply line from the high-frequency matching device to the electrode is suppressed to １ ／ or less of an oscillation wavelength of the high-frequency power.