JPH03292731A - Plasma processor - Google Patents

Abstract

PURPOSE:To manufacture the title plasma processor capable of easily adjusting the parallelism and interval between a pair of plasma producing electrodes by a method wherein the holding axle of one electrode is thrust borne by a bearing member held to be universally tilted by a spherical surface seat. CONSTITUTION:A pair of plasma producing one electrode 2 and the other electrode 3 opposing to each other are vertically arranged in chamber 1. A holding axle 5 is thrust borne by a bearing member 6 through the intermediary of thrust bearing 19; this bearing member 6 has spherical surface 6a on the rear surface so as to be mounted and held on a spherical surface seat 7 fixed on the surface of a ceiling wall member 1a in the chamber 1 by the spherical surface 6a; the bearing member 6 can be universally tilted by the spherical surface 6a held by the spherical surface seat 7. That is, the holding axle 5 can be turned clockwise and counterclockwise as shown by an arrow A so that the gradient of the upper electrode 2 with the lower electrode 3 may freely be changed to change the paralleism.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a plasma processing apparatus.

[Conventional technology]

Plasma processing equipment is in practical use, for example, in the manufacturing process of semiconductor devices, and is used to perform plasma etching (dry etching), plasma CVD,
Treatments such as plasma surface modification are being carried out.

In this plasma processing apparatus, as shown in FIG. 3, a pair of upper and lower plasma generating electrodes 51 and 52 are provided in a chamber 50 so as to face each other, and plasma is generated by a discharge phenomenon between the two electrodes. The object to be processed placed between the two electrodes is subjected to plasma processing using the plasma.

In this case, the mutual spacing and parallelism of the upper electrode 51 and the lower electrode 52 must be precisely adjusted. Therefore, in this plasma processing apparatus, the configuration that enables adjustment of the above-mentioned spacing and parallelism is as follows.

That is, while the lower electrode 52 is fixedly provided within the chamber 50, the upper electrode 51 is not directly fixed to the discharge chamber 50. In other words, the upper electrode 51 is supported by the support shaft 54 which is movable with respect to the chamber 50. To explain this in detail, as shown in FIG. 3, the support shaft 54 has an upper electrode 51 attached to its tip end, and a bolt 55 attached to its other end.
It is fixed to a base member 56 which is fixed to the upper surface of the chamber 50 with legs 55 as the legs.
A telescopic bellows 53 is provided between the back surface of the upper electrode 51 and the inner surface of the chamber 50 to maintain a vacuum in the chamber.

The inclination and height of the base member 56 change by rotating the bolts 55 and 55 in the forward and reverse directions, and the support shaft 54 changes accordingly.
The vertical position and tilt of will change.

As the vertical position and inclination of the support shaft 54 changes, the spacing and parallelism of the upper and lower electrodes 51 and 52 change. Therefore, by rotating the bolts 55.55, the spacing and parallelism between the upper and lower electrodes 51,52 can be adjusted to desired values.

[Problem to be solved by the invention]

However, in the case of the plasma processing apparatus described above, it is not easy to adjust the spacing and parallelism of the upper and lower electrodes 51 and 52 to appropriate conditions. This is because the rotation of the bolt 55 changes the height and inclination at the same time. Even if you try to slightly change only the spacing, the parallelism will change at the same time, so it is difficult to set both the spacing and the parallelism to desired values.

In view of the above circumstances, it is an object of the present invention to provide a plasma processing apparatus in which the parallelism and spacing of a pair of plasma generation electrodes can be easily adjusted.

[Means to solve the problem]

In order to solve the above problems, a plasma processing apparatus according to the present invention includes a chamber, a fixed spherical seat that maintains a fixed attitude with respect to the chamber, and a fixed spherical seat that is supported in a manner that allows universal tilting. The bearing includes a member, a support shaft that is thrust-beared by the member and whose tip faces into the chamber from outside the chamber, one electrode attached to the tip of the support shaft, and the one electrode inside the chamber. The other electrode is provided facing the other electrode, so that a discharge occurs between the two electrodes, and the one electrode can be moved into and out of contact with the other electrode by the action of a driving means that moves the support shaft. [Function] In the plasma processing apparatus of the present invention, the support shaft of one electrode is thrust-beared by a member, and this bearing is configured such that the member can be tilted universally by a spherical seat. Since the electrode is supported in such a manner that the electrode can freely change its inclination using the spherical seat as a fulcrum.

Therefore, when this one electrode (movable electrode) is pressed against the other electrode (fixed electrode), this one electrode comes into surface contact with the other electrode, and the parallelism is automatically adjusted.

In the plasma processing apparatus of the present invention, the support shaft is thrust-beared by a member, so when the support shaft is thrust, one electrode comes into contact with and separates from the other electrode while maintaining parallelism.

〔Example〕

Next, one embodiment of the plasma processing apparatus according to the present invention will be described in detail with reference to the drawings.

FIG. 1 shows the outline of the configuration of the plasma processing apparatus of this embodiment, and FIG. 2 shows the details of the structure of the plasma processing apparatus of this embodiment.

In this plasma processing apparatus, a pair of upper and lower plasma generation electrodes (one electrode) 2 and an electrode (the other electrode) 3 are disposed in a chamber 1 so as to face each other. The object to be processed (such as a wafer) 2 placed between the picture electrodes 2 and 3 is generated by the plasma generated by the discharge phenomenon between the picture electrodes 2 and 3.
5 is subjected to plasma treatment. lb is an exhaust port.

In this plasma device as well, the upper electrode 2 is attached to and supported at the tip of a support shaft 5 that faces from outside the chamber to inside the chamber.

However, this support shaft 5 is thrust-beared by a member 6 via a thrust bearing 19, and this bearing has a spherical surface 6a on the lower surface, and this spherical surface 6a is used to support the ceiling wall member 1a of the chamber 1. It is mounted and supported on a spherical seat 7 fixed to the upper surface, and is different from the conventional one in this point. Since the bearing member 6 is supported by the spherical seat 7 with its spherical surface 6a, universal tilting is possible. That is, as the support shaft 5 swings to the left or right as shown by arrow A in FIG. 1, the inclination of the upper electrode 2 with respect to the lower electrode 3 changes freely, and the degree of parallelism changes.

A base member 10 provided at the other end of the support shaft 5 is screwed to a threaded rod 12 that is driven to rotate forward and backward by a pulse motor 11, and as the screw rod 12 rotates forward and backward, the arrow B in FIG.
Move up and down as shown. And base member 10
As the support shaft 5 moves up and down, the upper electrode 2 moves up and down.
The distance between the lower electrode 3 and the lower electrode 3 is changed. In other words,
The base member 10, pulse motor 11 and threaded rod 1
Reference numeral 2 constitutes a driving means for moving the support shaft 5 in the direction in which the electrodes 2.3 move toward and away from each other.

In this case as well, an expandable bellows 4 is provided between the back surface of the upper electrode 2 and the inner surface of the chamber 1, but since this expandable bellows 4 flexibly expands and contracts in accordance with the movement of the support shaft 5, The movement of the electrode 2 is not hindered.

The support shaft 5 is extended into the chamber 1 by the action of the pulse motor 11, and the upper electrode 2 is brought into close contact with the lower electrode 3. Since the upper electrode 2 is naturally completely parallel to the lower electrode 3, the clamp 15 is The bearing fixes the inclination of the member 6 with respect to the spherical seat 7. In this state, if the pulse motor 11 is driven to move the support shaft 5 in the vertical direction, the upper electrode 2 will move toward and away from the lower electrode 3 while remaining completely parallel to it.

In this plasma processing apparatus, the axis of the support shaft 5 is a spherical surface 6a.
coincides with the normal of This has the advantage that both the amount of vertical movement when changing the parallelism and the misalignment of the axis of the upper electrode with respect to the lower electrode can be minimized.

Next, other configurations of the plasma processing apparatus of the example will be explained.

The upper electrode 2 and the lower electrode 3 are cooled by water flowing through the channels 2a and 3a. Further, necessary processing gas is introduced through the flow path 2b of the upper electrode 2 and the pipe 16. The lower surface of the upper electrode 2 has many pores 2 for blowing out the processing gas.
c... is provided. The lower electrode 3 is provided with high frequency power supply means RF. Furthermore, a lifting means (for example, a wafer lifting pin) 26 is provided near the center of the lower electrode 3 for placing the object to be processed 25 on the lower electrode 3.

The dial gauge 20 measures the vertical movement amount of the base member IO (that is, the amount corresponding to the distance between the upper and lower electrodes 2.3).
shows. That is, the measuring rod 21 that contacts the shoulder 10a of the base member 10 from above moves up and down as the Hess member 10 moves up and down, and this movement is displayed on the dial gauge 20.

The rotation of the pulse motor 11 is transmitted to the threaded rod 12 via a pulley 17 and a transmission belt 18. The insulating material G is for ensuring the necessary electrical insulation of the electrodes 2.3.

Note that the above plasma processing apparatus includes, in addition to the configuration shown in the figure,
Vacuum evacuation means for creating a necessary vacuum atmosphere in the chamber 1, means for supplying inert gas and material gas, power supply means for applying high frequency voltage to each electrode for plasma generation, etc. are all normally used. Needless to say, it is provided with the necessary configuration.

This invention is not limited to the above embodiments. For example, the axis of the support shaft 5 does not have to coincide with the normal line of the spherical surface 6a.

〔Effect of the invention〕

In the plasma processing apparatus of the present invention, since the distance between the pair of electrodes for plasma generation can be changed independently of the adjustment of parallelism, it is extremely easy to adjust the distance between the electrodes.

[Brief explanation of drawings]

FIG. 1 is a schematic sectional view showing the configuration of a plasma processing apparatus according to an embodiment of the present invention, FIG. 2 is a partial partial view showing the details of the configuration of this plasma processing apparatus, and FIG. 1 is a schematic cross-sectional view showing the configuration of a conventional plasma processing apparatus. 1... Chamber 2... Upper electrode (one electrode) 3
... Lower electrode 5 ... Support shaft 6 ... Bearing is a member
6a... Spherical surface 7... Spherical seat (fixed spherical seat)
10...Base member ll...Pulse motor
12... Threaded rod 25... Object to be processed

Claims (1)

[Claims] 1 A chamber, a fixed spherical seat that maintains a fixed posture with respect to the chamber, a bearing member supported by the fixed spherical seat in such a way as to allow universal tilting, and a tip of the bearing member that is thrust-beared by the bearing member. includes a support shaft facing into the chamber from outside the chamber, one electrode attached to the tip of the support shaft, and another electrode facing the one electrode inside the chamber,
A discharge is generated between the two electrodes, and
A plasma processing apparatus, wherein the one electrode can be moved into and out of contact with the other electrode by the action of a driving means that moves the support shaft.