JP3255966B2 - Plasma processing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plasma process used for, for example, an operation of oxidizing and removing a resist film on an object to be processed such as a wafer in a plasma atmosphere in a semiconductor manufacturing process in the electronics industry, and etching a silicon substrate. It relates to a processing device.

[0002]

2. Description of the Related Art Generally, in a semiconductor manufacturing process, in order to remove a resist film on a wafer by an ashing process, the process is performed by performing a plasma discharge in a vacuum vessel. As a plasma processing apparatus for performing such processing, an apparatus in which a wafer is placed inside a vacuum vessel and a heater for heating is arranged outside the vacuum vessel is known. In such an apparatus, an ashing process is performed by heating a wafer placed on the stage from outside the vacuum vessel.

[0003]

However, in the above-mentioned conventional apparatus, the object to be processed is heated from the outside of the vacuum vessel, so that heat is given to the vacuum vessel and the gas in the vacuum vessel. There was a problem that was bad. Further, since the heater is arranged outside the vacuum vessel, there is a problem that the arrangement area is large and the space factor is bad.

The present invention has been made in view of the above circumstances, and an object of the present invention is to enable a large amount of objects to be simultaneously processed when performing an ashing process, an etching process, and the like, and to heat the objects to be processed. An object of the present invention is to provide a plasma processing apparatus that can be efficiently performed.

[0005]

Means for Solving the Problems Claim 1 of the present invention
The plasma processing apparatus described in the above, in a vacuum vessel, comprising a plurality of plates arranged in multiple stages in the vertical direction, and a heat source arranged adjacent to the plurality of plates, the vacuum
Inside the container, a heater column having a hollow portion extending in the vertical direction inside, and a plurality of grooves formed on the outside and having a plurality of grooves formed at intervals in the vertical direction is erected. Means for solving the above problem is that a plate is detachably provided and the heat source is disposed in the hollow portion of the heater column. In the plasma processing apparatus according to the second aspect , the plurality of heater columns are provided upright, and a gap is provided between a groove of each heater column and a plate.

[0006]

According to the first aspect of the present invention, since a plurality of plates are arranged in the vacuum vessel, a plurality of objects to be processed are placed on each plate during the heat treatment. Therefore, the plurality of objects are heated at the same time. Further, since the plates are arranged in multiple stages and the heat source is arranged in the vacuum vessel adjacent to the plates, the heat from the heat source is efficiently transmitted to the workpiece on each plate. In addition, since a heat source is arranged inside the heater pillar and a plate is attached to the heater pillar, heat is quickly transmitted to the workpiece by heat conduction in the heater pillar and the plate, and the heating efficiency for the workpiece is improved. And heat is evenly transmitted to the object. In the invention according to claim 2, since a gap is provided between the groove of each heater column and the plate, even when the plate thermally expands due to heating, the plate is relatively displaced within the gap between the heater column and the plate. No distortion occurs in the plate itself and the heater column.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the plasma processing apparatus of the present invention will be described in detail with reference to embodiments. FIGS. 1 to 4 show one embodiment of a plasma processing apparatus according to the present invention. In these figures, reference numeral 1 denotes a plasma processing apparatus. This plasma processing apparatus 1 is for removing a resist film on a wafer W as shown in FIG.
Heater columns 3,3 covering these heaters 2,2, plate 4 between these heater columns 3,3, and plate 4
(See FIG. 3), an exhaust pipe 6, a gas introduction pipe 7, and an internal electrode 8 are provided in a vacuum vessel A, and an external electrode 9 is provided outside the vacuum vessel A. Is attached.

The vacuum vessel A is composed of a cylindrical main body 11 made of quartz, and an upper lid 12 and a lower lid 13 made of ceramics for closing upper and lower openings of the main body 11. Holes 13a, 13a are formed in the bottom cover 13. Heater columns 3 and 3 having heaters 2 and 2 provided therein are fitted into these holes 13a and 13a, respectively.

The heater pillars 3, 3 are hollow pillars as shown in FIG.
a, 13a. These pillars 3,3
As shown in FIG. 3, is a member for transmitting heat from the heaters 2 and 2 in the hollow portions 3a and 3a, and is made of, for example, aluminum having a high thermal conductivity. Heaters 2 and 2
It is a rod-shaped member that is inserted tightly into the hollow portion of the heater pillars 3, 3, and has a lead wire 2 at its lower end as shown in FIG.
a and 2a are connected. The joint between the heater column 3 and the bottom lid 13 is adapted to maintain the airtightness in the vacuum vessel A, and for example, an O-ring 3b is used as shown in FIG. When the O-ring 3b is used, the heater column 3
An O-ring 3b is disposed on a flange 3c at the lower end of the rim, and the flange 3c and the bottom cover 13 are fixed by bolts 3d, 3d.

As shown in FIG. 3, a plurality of grooves 14 are provided at regular intervals in the height direction.
Are provided, and holes 15 for bolts are formed. The bolt holes 15 are formed at two locations above and below a surface of the heater columns 3 and 3 facing each other. The grooves 14 lock the ends of the plates 4 as shown in FIG.
Are formed at the same height on the surfaces facing each other.

The plates 4 are for mounting the wafers W as shown in FIGS. 3 and 4, and are mounted horizontally on the heater columns 3, 3. Plate 4
Are disk-shaped, and the engaging portions 4a, 4a
Are formed in a protruding state, and are made of, for example, aluminum having a high thermal conductivity. The plate 4 has substantially the same thickness as the width of the groove 14 in the vertical direction, and has a central circular portion slightly larger than the wafer W to be processed. Further, the distance between the side end faces of the locking portions 4a, 4a is formed to be slightly shorter than the distance between the inner surfaces of the opposed grooves 14, 14. Thus, the plate 4 is set so as to allow horizontal relative movement when thermally expanded. Such a plate 4 ...
Are locked in the grooves 14 of the pillars 3, 3, and the locking portions 4 a are fixed to the grooves 14 by restraining plates 5.

As shown in FIG. 3, the holding plates 5 are for closing the ends of the grooves 14, and are attached vertically along the columns 3, 3. As shown in FIG. Bolt holes 5a are formed in the holding plates 5 at positions corresponding to the bolt holes 15 of the columns 3, 3, and the pressing plates 5 are formed by the bolts 16 into the columns 3. , 3 are fixed.

As shown in FIG. 1, an exhaust pipe 6 and a gas introduction pipe 7 are attached to the inside of the vacuum vessel A through the upper lid 2 from outside the vacuum vessel A. The exhaust pipe 6 and the gas introduction pipe 7 have a negative pressure inside the vacuum vessel A, and are fixed to the upper lid 2 so as to maintain an airtight state. further,
Inside the vacuum vessel A, an internal electrode 8 is disposed concentrically with the vacuum vessel main body 11, and an external electrode 9 corresponding to the internal electrode 8 is disposed along the outer surface of the vacuum vessel A. The internal electrode 8 and the external electrode 9 perform a discharge between these electrodes, and generate plasma by the discharge.

Next, a method of using the plasma processing apparatus 1 having such a configuration will be described. First, the wafer W is placed on each plate 4 sequentially from the bottom. Then, the vacuum vessel A is made airtight, the exhaust pipe 6 and the gas introduction pipe 7 are operated, and the inside of the vacuum vessel A is set to a negative pressure. Then, the heaters 2 and 2 are energized and heated through the lead wires 2a and 2a. After a sufficient pressure state is reached, the internal electrode 8
And a voltage is applied to the external electrode 9 to cause a discharge, and the vacuum vessel A
Generate plasma inside.

Thus, according to the plasma processing apparatus 1 as described above, it is possible to simultaneously process a large number of wafers W. Since the columns 3, 3 and the plates 4 have high thermal conductivity, the heat of the heaters 2, 2 is efficiently transmitted to the wafers W. Before the ashing process is started, the inner surface of the groove 14 of the pillar 3 and the end surface of the locking portion 4a of the plate 4 are arranged with a gap therebetween. Becomes narrower and plate 4
Does not press the inner surface of the groove 14 of the column 3, and no distortion occurs in the column 3 and the plate 4. Further, since the heater 2 is installed in the column 3, the device 1 is smaller in size than a conventional heater installed outside the vacuum vessel. Further, since all the plates 4 are fixed collectively via the holding plate 5 to fix the plates 4, the bolts 16 are not loosened due to the heat cycle and the plates 4 are not distorted. , Plates 4... Can be fixed in a short time without requiring much labor.

The plasma processing apparatus of the present invention is not limited to the case where the number of heater columns is two, but may be a configuration where one or three or more heater columns are provided.

[0017]

As described above, in the plasma processing apparatus according to the first aspect, since a plurality of plates are arranged in the vacuum vessel, a plurality of workpieces can be processed simultaneously. In addition, since the plates are arranged in multiple stages and the heat source is arranged adjacent to the plates, heat from the heat source is efficiently transmitted to the workpiece on each plate. Further, since the heater is provided in the vacuum vessel, the size of the apparatus can be reduced.

Further , since the heat source is arranged inside the heater column and the plate is attached to the heater column, the efficiency of heating the object to be processed is good and the heat is uniformly transmitted to the object to be processed. Therefore, it is possible to efficiently perform a good process.

Further, the plasma processing apparatus according to claim 2, since a gap is provided between the groove and the plate of each heater post, plate, even when the thermal expansion upon heating,
The plate is displaced relative to the heater column, and the plate itself and the heater column are not distorted.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a plasma processing apparatus of the present invention.

FIG. 2 is a horizontal sectional view of the plasma processing apparatus shown in FIG.

FIG. 3 is a plan view of a plate of the plasma processing apparatus shown in FIG.

FIG. 4 is a front view in which a part of a main part of the plasma processing apparatus shown in FIG. 1 is viewed in cross section.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plasma processing apparatus 2 Heater (heat source) 3 Heater column 3a Hollow part 4 Plate 14 Groove A Vacuum container

Claims (2)

(57) [Claims] To 1. A vacuum chamber comprising a plurality of plates arranged in multiple stages in the vertical direction, and a heat source disposed adjacent to the plurality of plates, in the vacuum container, the vertical direction in the interior The hollow part extending to
And a plurality of externally formed
Erect a heater column with a number of grooves,
The plate is detachably provided in the groove, and the heater column is provided.
The plasma processing apparatus , wherein the heat source is disposed in the hollow portion . 2. The plasma processing apparatus according to claim 1,
And a plurality of the heater pillars
A gap between the groove and the plate
Plasma processing equipment.