JPH0325938B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is used for etching and cleaning semiconductor wafers used in the manufacture of chips on which large integrated circuits such as LSI or VLSI are formed, and for ashing (ashing and peeling) the photoresist layer on the surface of semiconductor wafers. The present invention relates to a plasma processing apparatus.

Microfabrication in semiconductor integrated circuits requires exposure and
a step of etching an insulating film, a semiconductor film, or a conductive film formed on a semiconductor wafer that is not covered with a resist film formed with a pattern by development; a step of cleaning the film;
The process includes an ashing process in which the resist film used as a mask is removed from the wafer surface after etching is completed.

Conventionally, etching, cleaning or ashing has been carried out by wet processing using various liquid chemicals such as inorganic acids and organic solvents. However, such wet processing cannot improve the precision of microfabrication and has problems such as waste liquid treatment.In particular, with the recent development of VLSI, patterns tend to become even finer, so it is difficult to improve the precision of microfabrication using plasma. So-called dry etching
Moving to dry ashing.

For this reason, various plasma processing apparatuses have been proposed that perform dry etching, etc., but most of these are devices in which semiconductor wafers are manually loaded into or removed from a plasma generation chamber. Therefore, the work efficiency is extremely low, the wafer itself is often damaged, and the product yield is not favorable. For this reason, devices for automatic processing have also been proposed. For example, it is shown in Japanese Patent Application Laid-Open No. 53-90870.
However, in such an apparatus, since the chamber opens at right angles to the direction of conveyance of the cassette containing wafers, the direction of conveyance of the cassette must be changed midway through the process, which complicates the mechanism of the apparatus itself. , there is a problem of increasing the size.

In view of the conventional problems as described above, the present inventors
The present invention was developed to effectively solve this problem, and its purpose is to provide an automatic plasma processing apparatus that can be made compact with a simple mechanism and that can continuously and automatically process semiconductor wafers. There is something to do.

In order to achieve such an object, the first invention is provided with a transport member for transporting a cassette containing a plurality of wafers in the main body of the apparatus, and a plasma generation chamber that is open in the transport direction of the transport member, A lid body that automatically opens and closes the opening of this chamber is attached, and an arm member that performs vertical and horizontal movements feeds the cassettes on the transport member into the chamber, and also transports the cassettes inside the chamber onto the transport member. The main point is that it has been taken out. The gist of the second invention is that the conveyance member of the first invention is integrally attached to the arm member.

A preferred embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is an overall perspective view of a plasma processing apparatus according to the first invention. In the figure, 1 is a plasma processing apparatus that has two chambers and can process a large number of wafers at the same time.This plasma processing apparatus 1 has a control box 3 equipped with various control buttons 2 in the center. However, in addition to various wiring, a vacuum pump, a high frequency power source, etc. are incorporated in this control box 3.

Long box-shaped cases 4 and 5 are connected to the loader side and unloader side of the control box 3, and doors 6 are formed on the sides of the cases 4 and 5.
In addition, openings 7 and 8 are formed in the center of the upper surfaces of the cases 4 and 5 in the longitudinal direction, and endless belts 11 and 12, which are conveying members for a cassette 10 containing a plurality of wafers 9, are formed in the openings 7 and 8 in the longitudinal direction. is coming. The upper surface of these endless belts 11, 12 is the case 4,
5, and its width is approximately flush with the upper surface of the opening 7,
8, the endless belt 11,
There is a gap 1 between the side end of 12 and the openings 7 and 8.
3 and 14 are formed, and the upper part of a bifurcated arm member 15 having an angular side surface can protrude from the gaps 13 and 14.

Further, at the front end of the case 4, there is provided a communication section 16 incorporating a lift mechanism etc. for placing the cassette 10 containing the wafers 9 that have been processed in the previous process onto the endless belt 11. A communication section 17 is used to transfer the cassette 10 containing the wafer 9 that has been subjected to plasma processing to the next process.
has been established.

Furthermore, a cover 18 with openings on the front and rear sides is provided above the control box 3, and this cover 18
A plasma generation chamber 19 is disposed inside. This plasma generating chamber 19 is constructed by fixing an electrode plate to the outer periphery of a quartz tube having a substantially cylindrical shape to apply a high frequency wave, and openings at both ends face toward the transport direction of the cassette 10. It's open. In other words, the transport direction of the cassette 10 and the axis of the chamber 18 coincide.

2 and 3 show a mechanism that allows the arm member 15 to move up and down and horizontally, and a cylinder unit 20 is installed at the bottom of the case 4.
A support body 22 is fitted onto the rod 21 of this cylinder unit 20, and a cylinder unit 23 is installed vertically on the upper surface of this support body 22.
is erected, and the rod 2 of this cylinder unit 23 is
The lower end of the arm member 15 is fixed to the tip of the arm member 4. The arm member 15 moves horizontally as the rod 21 of the cylinder unit 20 moves in and out, and moves up and down as the rod 24 of the cylinder unit 23 moves in and out.

Further, the above mechanism is also provided inside the case 5.

4 to 6 show the opening and closing operation of the lid body 25 that opens and closes the opening of the chamber 19,
A cylinder unit 26 is vertically provided below the front end of the cover 18, that is, at the bottom near the boundary between the control box 3 and the case 4. The rod 27 of this cylinder unit 26 is attached to the cover 18.
It passes through a bracket 28 bent inward from the lower front end of the rod 27 so that it can extend and retract vertically, and a support 29 is fixed to the tip of the rod 27. The cover body 25 is attached to the arm 3 on the side surface of the support body 29.
0 and 30, and these arms 30 and 30 are biased counterclockwise in the figure by a spring provided within the support body 29. Therefore, when the rod 27 is in the retracted state as shown in FIG.
It protrudes upward from the upper end of the .

When the rod 27 protrudes from the state shown in FIG. 4, the lid 25 rises accordingly, and its upper end abuts against the ceiling surface 18a of the cover 18. Then, when the rod 27 protrudes further, only the support body 29 rises, and the arms 30, 30 rotate clockwise accordingly. As a result, the lid 25 moves rightward in the figure, ie, toward the opening 19a of the chamber 19, while sliding its upper end on the ceiling surface 18a.
When the upper end of the support body 29 comes into contact with the ceiling surface 18a, that is, at the upper limit of movement of the rod 27,
The seal ring 31 attached to the side surface of the lid body 25 comes into contact with the flange 19b at the front end of the chamber 19, thereby airtightly closing the opening 19a as shown in FIG. Then, by the reverse operation to the above, the original state as shown in FIG. 6 is returned.

The lid 25 that opens and closes the opening at the rear end of the chamber 19 is also operated by the same mechanism as described above.

The seventh invention describes the operation of the first invention having the above configuration.
This will be explained based on the diagram.

First, as shown in FIG. 7A, when the cassette 10 reaches the tip of the endless belt 11, the endless belt 11 is stopped by the limit switch, and at the same time, the lid 25, which had closed the front end opening of the chamber 19, is closed.
descends and opens the opening. Next, the arm member 15 rises as shown in (b) and lifts the cassette 10 from the endless belt 11, and the arm member 15 moves rightward as shown in (c) to feed the cassette 10 into the chamber 19. Next, as shown in D, the arm member 15 descends slightly to place the cassette 10 on the mounting table 32 disposed inside the chamber 19, and as shown in E, the arm member 15 retreats, and at the same time, the lid 25 on the loader side rises and hermetically closes the opening of the chamber 19.

After performing plasma treatment in the chamber for a predetermined period of time, the lid body 2 on the unloader side
5 to form a rear end opening of the chamber 19, and then lower the arm member 15 on the unloader side as shown in FIG.
enters the chamber and is located below the cassette 10. Thereafter, the arm member 15 moves backward with the cassette placed on its tip, and the cassette 10 is transferred onto the endless belt 12 on the unloader side, as shown in FIG. This cassette 10 is connected to an endless belt 1 as shown in FIG.
2 to the rear and sent to the next process.

In other words, as shown in FIGS. 1 and 7, the cassette 10 is transported substantially forward in a substantially straight line without moving backward.

FIGS. 8 and 9 show the operating mechanism of the arm member as a second invention different from the first invention.

That is, in the second invention, a support 35 is fixed to the tip of the rod 34 of the cylinder unit 33 installed horizontally, and the guide rod 3 is attached to the support 35.
By passing through the guide rods 6 and 36, the support body 35 can be horizontally moved along the guide rods 36 and 36 by the movement of the rod 34 in and out. A guide rod 3 is placed on this support 35 via a support plate 37.
8 and 38 are provided in the vertical direction, and a cylinder unit 39 is provided upright, and this cylinder unit 3
The lower surface of the base of the arm member 41 is fixed to the tip of the rod 40 of No. 9. This arm member 41 has a horizontal upper surface and has a groove 42 extending in the length direction on the upper surface, and this groove 42 divides the arm member 41 into left and right protrusions 41a and 41b. . A hole through which the guide rod 38 is inserted is formed in the left protrusion 41a, and the rod 40 is inserted into the hole.
The arm member 41 moves up and down along the guide rod 38 in accordance with the movement of the arm member 41 into and out. Further, shafts 43 and 44 are rotatably inserted into the tip and rear ends of the right protrusion 41b, pulleys 45 and 46 are fitted to both ends of these shafts 43 and 44, and a belt is inserted between the pulleys 45 and 46. 47, 47 are stretched, and the belt 47 is driven by a motor (not shown).

FIGS. 10 and 11 show another embodiment of a mechanism for making the arm member 41 move up and down and horizontally, and the same members are given the same numbers.

That is, a shaft 49 which is rotated by a motor 48 and has a male threaded portion is installed in the horizontal direction, and the support body 35 is screwed onto this shaft 49, so that the support body 35 is rotated by the rotation of the shaft 49. is moved horizontally along the guide rod 36. A motor 50 is fixed on the support body 35, and a shaft 51 which is rotated by the motor 50 and has a male thread is provided upright, and the arm member 41 is screwed onto this shaft 51. . Therefore, the motor 50
By driving the arm member 41, the arm member 41 moves up and down along the guide rod 38.

The second invention having the above-mentioned structure also has a semiconductor wafer 9 by the same effect as shown in FIG.
A cassette 10 containing ... is sent into a chamber 19, and after being subjected to plasma treatment for a predetermined period of time, the cassette 10 is taken out from the chamber 19.

In the second invention as well, the cassette 10 is conveyed substantially forward on a substantially straight line without moving backward.

As is clear from the above description, according to the present invention, a transport member for transporting a cassette containing a plurality of semiconductor wafers is provided in a case or the like of a plasma processing apparatus, and a plasma generation chamber that opens in the transport direction of the cassette is provided. The cassettes can be loaded and unloaded into the chamber automatically by installing an arm member that moves up and down and horizontally, or by integrally attaching the conveying member to the arm member. Since it is possible to automatically feed and take out wafers into and out of the chamber, it is possible to efficiently process a large number of wafers with a small number of parts, and to manufacture a plasma processing system that is less likely to break down and can be made more compact at a low cost. It has many advantages.

[Brief explanation of the drawing]

The drawings show an example of the implementation of the present invention,
FIG. 1 is an overall perspective view of the plasma processing apparatus according to the first invention, FIG. 2 is a front view showing a mechanism for making the arm member perform vertical movement and horizontal movement, FIG. 3 is a side view of the same mechanism, and FIG. 6 through 6 are partially cutaway front views showing the mechanism for opening and closing the lid, FIGS. A front view showing a mechanism for vertically moving and horizontally moving the arm member of the plasma processing apparatus according to the invention, FIG. 9 is a side view of the same mechanism, and FIG. 10 is a front view similar to FIG. 8 showing another embodiment. 11 are side views similar to FIG. 9 of the same embodiment. In addition, in the drawing, 9 is a wafer, 10 is a cassette, 1
1, 12, 47 are conveyance members, 15, 41 are arm members, 19 is a plasma generation chamber, 19a
25 is an opening of the chamber, and 25 is a lid.

Claims (1)

[Scope of Claims] 1. In an automatic plasma processing apparatus that processes wafers by storing a cassette containing a plurality of wafers in a chamber, this automatic plasma processing apparatus operates from the upstream side to the downstream side in the transport direction of the cassettes. A loader-side transport member, a loader-side lid, a chamber, an unloader-side lid, and an unloader-side transport member are sequentially arranged in series, and each of the loader-side and unloader-side transport members is arranged between the transport member and the chamber. It is characterized by consisting of an arm member that can move up and down and horizontally to transfer cassettes, and a pair of endless belts that run in the longitudinal direction of this arm member and are provided on the arm member so as to protrude from the top surface. automatic plasma processing equipment. 2 In an automatic plasma processing apparatus that processes wafers by storing a cassette containing a plurality of wafers in a chamber, this automatic plasma processing apparatus sequentially transports the cassettes from the upstream side to the downstream side in the transport direction on the loader side. A member, a loader-side lid, a chamber, an unloader-side lid, and an unloader-side conveying member are arranged in series, and the loader-side and unloader-side conveying members are constituted by endless belts, and a An automatic plasma processing apparatus characterized in that cassettes are transferred by a pair of arm members that can be moved up and down and horizontally.