JP2882765B2 - Gate valve for thin film forming 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 thin film forming apparatus suitable for manufacturing, for example, an ultra-high-density integrated circuit, and more particularly, to a single decompression chamber (chamber) for performing single wafer processing. The present invention relates to an improvement of a gate valve used when a wafer is taken in and out between the inside and outside of the gate valve.

[0002]

2. Description of the Related Art Conventionally, the degree of integration of LSI has been increasing year by year, and in order to realize ultra-high integration in the future, a technique for realizing a laminated structure of extremely thin thin films has been established. There has been a demand for a technology for increasing the speed of the system.

That is, when high-speed processing is required to perform one processing on one wafer, in other words, for example, the time taken in and out of the chamber for transfer to the wafer and the chamber for sputtering, It may be required to complete the entire process within one minute.

In such a case, a time allowable for opening and closing a gate valve for opening and closing an opening formed in a partition wall between a transfer chamber and a sputtering chamber, loading and unloading of a wafer, setting of a sputtering process, and the like, that is, Assuming that the minimum time required for film formation is about 30 seconds, a gate valve that can be opened and closed in about 0.5 seconds is required in order to cope with this.

[0005] Further, when a wafer transfer process between a load chamber for setting a wafer in the apparatus and unloading for removing the wafer from the apparatus is performed at a high speed,
In other words, for example, when transferring a wafer between a wafer stocker that stores several tens of wafers and an electrostatic suction and transfer mechanism, a high-speed gate valve that can be opened and closed in about 0.5 seconds is similarly provided. Required to be used.

Here, as a conventional gate valve, for example, as shown in FIG. 30, a gate plate 1410 'having a predetermined thickness with an O-ring 1411 mounted on its upper surface, and a gate plate 1410' are provided so as to face the gate plate 1410 '. Connection board 141
0 ″ is connected by a link piece 1420, and a return coil spring 1421 is interposed between the two plates 1410 ′ and 1410 ″ to open the partition 1422 that partitions the connection board 1410 ″ into upper and lower chambers 1430 and 1431. There is known one that can move in a direction perpendicular to the direction penetrating 1423 (the left-right direction in FIG. 30).
Reference numeral 1424 denotes a stopper for preventing the movement of the gate plate 1410 '.

In this case, in order to close the opening 1423 by the gate plate 1410 ', the gate plate 1410' is positioned below the opening 1423 with the coil spring 1421 compressed, and then the link piece 1
The connecting board 1410 ″ is moved to the side of the stopper 1424 to rotate the 420. At this time, the connecting board 1
The gate plate 1410 'is moved to the stopper 1 by the movement of 410 ".
424, but the gate plate 141
0 ′ is pushed up toward the opening 1423 against the urging force of the coil spring 1421, and the gate plate 141 is pressed.
0 'closes the opening 1423.

[0008]

However, in such a conventional gate valve, it is necessary to make the thickness of the gate plate 1410 'considerably large in order to connect the link pieces 1420 and abut against the stopper 1424. ,at least,
Moving the connecting substrate 1410 ″;
A step of pushing up 10 ′ is necessary, and the opening 1423
It is not suitable when it is required to open and close at a high speed.

Further, since at least two members, that is, a gate plate 1410 'and a connecting substrate 1410 "are required,
In addition to requiring a large mounting space, increasing the overall mass, and hindering high-speed transportation, it is difficult to obtain a sufficiently closed state. There is a problem that it becomes an obstacle to perform.

[0010]

SUMMARY OF THE INVENTION The invention of claim 1 has been made to solve the above-mentioned problems, such as the limitation of increasing the opening / closing speed of the opening, and the like. In a gate valve of a thin film forming apparatus configured to be capable of opening and closing an opening formed in a partition wall, a thin plate formed so as to cover the opening and a direction substantially parallel to the plate surface. And a voltage supply means for applying a DC voltage between the thin plate and the partition wall.

According to a second aspect of the present invention, in the first aspect of the present invention, the thin plate is polished at least on a plate surface facing an outer peripheral portion of the opening.

[0012]

According to the first aspect of the present invention, in order to close the opening, the thin plate is swung by the driving means so as to face the opening, and subsequently, the voltage supply means is actuated to cause the thin plate and the partition to be closed. During this time, a DC voltage is applied to electrostatically attract the thin plate toward the opening. In this case, since the swing of the thin plate is performed under a reduced pressure atmosphere, the opening and closing operation of the thin plate is performed at a high speed.

According to the second aspect of the present invention, since the plate surface of the thin plate is polished, the coefficient of friction between the outer peripheral portion of the opening and the thin plate surface on the side opposite to the opening becomes extremely small, and the vibration of the thin plate is reduced. Further speed up the movement.

[0014]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an overall configuration diagram of a thin film forming apparatus to which a gate valve according to the present invention is applied. The apparatus shown in FIG. 1 has four decompression chambers (process chambers), that is, a sputter chamber 101a for forming a metal thin film, a sputter chamber 101b for forming an insulating thin film, a cleaning chamber 101c, and an oxidation chamber 101d. Reference numeral 102 denotes a wafer loading chamber, which is used when setting a wafer in an apparatus. Also, 103
Denotes an unload chamber, which is a chamber used when a wafer is taken out of the apparatus. Reference numeral 104 denotes a transport chamber, which is used when transferring a wafer to any of the above four process chambers. In this case, the transfer of the wafer 106c is performed by using a later-described electrostatic chuck type wafer chuck 114 or the like. That is,
After the wafer is sucked by the wafer chuck 114, the wafer is set on the wafer holders 107a to 107d in a predetermined chamber by using, for example, a magnetic levitation type transfer mechanism.

Here, each of the wafer holders 107a-107
d holds and holds the wafer by the above-described electrostatic suction method,
Then the gate valve 105 of the corresponding process chamber
a to 105d (the gate valve 105a of the process chamber 101a is not shown), and then the wafer holder (1) is opened.
07a), the whole is raised, the wafer is inserted into the predetermined process chamber 101a, etc., and the hermetic seal between the process chamber 101a, etc. and the transport chamber 104 is performed. In addition, FIG.
A state where a silicon wafer 106a and a wafer holder 107a are set in a sputtering chamber 101a for a metal thin film is shown.

Reference numerals 108a to 108d denote target chambers, and the targets 109a to 109d can be replaced without changing the vacuum state. A tuning circuit 110 is provided for each of the targets 109a to 109d.
a to 110d, RF power supplies 111a to 111d are connected to each other.
Also, RF power supplies 113a to 113d are connected via tuning circuits 112a to 112d, respectively. FIG.
Although not shown in FIG.
8d, 101a to 101d, 102, 103, 104
, Etc.) are connected to vacuum evacuation devices, respectively.

In FIG. 1 described above, the positional relationship between the target and the wafer shows a case where the wafer is located below and the target is located above, but the positional relationship between the upper and lower sides may be reversed. As an advantage of reversing this positional relationship, when the target is held by an electrostatic chucking mechanism (electrostatic chuck), if the target is located below,
For example, it is possible to avoid a situation where a target having a relatively large weight falls even when the attraction force is weakened due to a temporary fluctuation in the power supply voltage of the electrostatic chuck.

On the other hand, for example, as shown in FIG. 3, a configuration may be adopted in which the target 109a and the wafer 106a face each other in the left-right direction. According to this configuration, it is possible to prevent fragments of the wafer and dust attached to the wafer from falling onto the target, and to avoid contamination of the target, deterioration of the quality of the formed thin film, and the like.

Further, as shown in FIG.
9a may be arranged so that its surface is slightly inclined upward. This makes it easy to hold a heavy target, as well as preventing dust from adhering to the wafer surface and dropping of dust from the wafer to the target, as in the case of FIG.

Next, a method of manufacturing a capacitor structure as shown in FIG. 4 by using the thin film forming apparatus will be described.

The capacitor shown in FIG.
An Al thin film 304 and an Al ₂ O ₃ film 30 are formed on an N ⁺ diffusion layer 302 formed therein through an opening provided in an insulating film 303.
5, a three-layer structure of the Al thin film 306 is formed.

In the manufacturing process, first, the N ⁺ diffusion layer 302 is formed on a silicon substrate 301, and an insulating film 30 is formed thereon.
3 and a wafer 106e having an opening formed on the N ⁺ diffusion layer 302 is prepared.
02 on the wafer holder 107e. Next, after evacuating the loading chamber 102, the gate valve 105e is opened, the wafer 106c held by the electrostatic chuck 114 is loaded into the transport chamber 104, and the gate valve 105e is closed. Next, the wafer 106c is transferred to the cleaning chamber 101c and set.

In the cleaning chamber 101c, an extremely thin natural oxide layer or an adsorbed molecular layer formed on the surface of the N ⁺ diffusion layer 302, particularly a water adsorbed molecular layer, is formed at a low temperature (150 ° C. or lower) and the silicon Substrate 301
Can be removed (cleaning) without damaging the substrate. That is, the wafer is irradiated with Ar ions generated by the RF discharge at an energy that does not damage the Si crystal (for example, a kinetic energy of about several eV to about 30 eV, preferably 5 eV or less, more preferably 2-3 eV). .

By performing such surface cleaning, good electrical contact between the Al thin film 304 and the N ⁺ diffusion layer 302 can be obtained. That is, an ideal metal-semiconductor contact can be obtained without any heat treatment step thereafter. After the processing in the cleaning chamber 101c is completed, the sputtering chamber 101a for forming a metal thin film is formed.
The wafer 106a is transferred to the

At this time, since the transfer of the wafer is performed in the evacuated transport chamber 104, the metal thin film can be formed on the surface of the wafer in a clean state without contacting the wafer with the atmosphere. In the sputtering chamber 101a, an Al target 109a
Is used to form an Al thin film 304 on the wafer by a sputtering method.

Next, the wafer is placed in the oxidation chamber 10.
It is carried to 1d. Here, the wafer is 300 to 500
An oxygen gas is supplied while being heated to a temperature of ° C., and an Al ₂ O ₃ film 305 having a thickness of, for example, about 5 nm is formed on the surface of the Al thin film 304 by thermal oxidation.

Thereafter, the wafer is again put into the chamber 101.
a and an Al thin film 306 is formed. The wafer on which the thin film having the three-layer structure of Al—Al ₂ O ₃ —Al is formed is transported again in the transport chamber 104 and returned to the wafer stage 107f in the unload chamber 103. And the gate valve 10
After closing 5f, the inside of the unload chamber 103 is returned to the atmospheric pressure, and the wafer is taken out of the apparatus.

In the above example of the sequence of manufacturing the capacitor, a multilayer thin film structure can be realized without cleaning the wafer surface or exposing the interfaces between the films directly to the atmosphere.

The configuration of the thin film forming apparatus and the outline of the formation of the multilayer thin film structure have been described above. The details of each part of the apparatus and the process of forming the multilayer thin film structure will be described below.

FIGS. 5 and 6 are schematic views showing the details of the structure of the metal thin film sputtering chamber 101a, which is one of the process chambers. The transport chamber 104, the target chamber 108a, and the wafer holder 1 described above are shown in FIGS.
07a, gate valve 105a, target 109a,
The drawing includes the target holder electrode 401 and the like. The details of the target holder electrode 401 and the like will be described later.

FIG. 10 shows an example of a connection relationship between a vacuum exhaust device and a gas supply device centered on the sputtering chamber 101a for forming a metal thin film.
1, the same components as those in FIGS. 1, 2, and 5 are denoted by the same reference numerals.

As shown in FIG. 10, the process chamber 1
For example, a turbo molecular pump 501 having a magnetic levitation type rotor and a rotary pump 502 as a backup thereof are connected to the vacuum pump 01a. An oil trap 503 prevents backflow of oil from the rotary pump 502. In addition to the configuration shown in FIG. 10, for example, a system in which the ultimate vacuum degree of the chamber is further increased by connecting turbo molecular pumps in two stages in series may be adopted. In the case where sputtering is performed by flowing a gas, a structure in which a dry pump or the like that is resistant to a gas load may be used.

Here, the dry pump is a turbo molecular pump designed to be able to pull from atmospheric pressure to high vacuum. In this case, the rotor that rotates at high speed is supported,
And ball bearings that reduce friction are used,
Further, in order to suppress a rise in the temperature of the rotor, high-pressure oil is sprayed. Further, it is necessary to prevent the sprayed oil from entering the vacuum system and causing contamination.
Sealed using _two gases. In this case, for example, if the supply of the N ₂ gas is stopped during operation, a great deal of damage will be given to the vacuum system.

The transport chamber 104 is also connected to the same vacuum pumping system 501 'to 503' as the vacuum pumping device. Although not shown, the target chamber 108a also has a similar vacuum exhaust system. Therefore, each chamber is provided with a means for independently evacuating.

Reference numeral 504 denotes a gas supply device, which includes Ar, H
e, so that the gas such as H ₂ can be supplied to the process chamber 101a. For example, Ar gas is constantly flowed at a constant flow rate (1 to 5 l / min) and is purged out of the system by a purge line 505. Only when sputtering is performed, the valve 506 is opened, and a part of the gas is introduced into the process chamber 101a while being controlled by the mass flow controller 507 at a flow rate of, for example, 1 to 10 cc per minute.

In addition to this method, Ar gas is supplied from the gas supply system to the chamber 101 only when sputtering is performed.
a, and at other times, the gas supply is kept in a stopped state. In this method, a small amount of water molecules adsorbed on the inner wall of the gas pipe are retained.
Since it dissolves in the r gas, measures should be taken not to increase the moisture concentration of the gas. For example, when an Al thin film is formed by sputtering using an Ar gas having a water concentration of several tens of ppb or more, as shown in FIGS. 11A and 11B, the surface (several ppm, several hundred ppb) depends on the amount of water. This results in the formation of a thin film with severe irregularities. Since such a thin film cannot form a fine pattern with high accuracy, it cannot cope with miniaturization of a device, and furthermore, has a weak characteristic against electromigration when a large current flows, so that a reliable wiring cannot be obtained.

However, as shown in FIGS. 11 (c) and 11 (d), when the water content becomes 100 ppb or less, the surface becomes flat, and an Al thin film having large electromigration characteristics can be obtained.

In the present thin film forming apparatus, when an Ar gas supply method as shown in FIG. 10 is used, an Ar gas having a water content of 1 to 2 ppb or less can always be supplied to the chamber. High metal wiring can be formed.

However, when the apparatus is to be stopped for a long period of time, the valve 506 'may be closed to stop the Ar gas purge. On the other hand, when the device is later activated,
First, Ar gas is purged through a purge line 505,
After the water content is sufficiently reduced, the valve 506 is opened to introduce gas into the chamber. For this reason, for example, the purge line 5
Attach a moisture meter (dew point meter) to the tip of
It is possible to confirm that the temperature becomes 10 ° C. or less.

In order to improve the quality of a thin film formed by sputtering, it is necessary to sufficiently eliminate the entry of impurity molecules such as moisture during the film formation process. To this end, the above-described Ar gas introduction method may be adopted, but it is also necessary to minimize the outgassing from the surface of the chamber material or the gas piping material as much as possible. The wall material 402 of the chamber of the apparatus shown in FIG. 5 and the gas pipe of the gas supply device 504 shown in FIG. 10 are made of, for example, SUS304L or SUS316L, and the surface thereof reduces adsorption of H ₂ O molecules, In addition, a process for facilitating detachment is performed. Such a process employs, for example, a method described below.

First, the surface of the stainless steel is mirror-polished without a work-affected layer, and the inner surface of the pipe is subjected to, for example, electrolytic polishing, and the inner surface of the chamber is applied to the inner surface of the chamber using a technique such as electrolytic combined polishing. .

Next, purging is performed using Ar or He having a water content of about 1 ppb or less, and further purging is performed by raising the temperature to about 400 ° C., so that H ₂ O molecules adsorbed on the surface are almost completely removed. After desorption, pure oxygen having a water content of about 1 ppb or less is flowed in the same manner as described above,
The temperature is raised to ５550 ° C. to oxidize the inner surface. The oxide film obtained by thermally oxidizing the stainless steel surface in this manner is more resistant to corrosive gases such as HCl, Cl ₂ , BCl ₃ and BF ₃ than a passive film formed using conventional nitric acid or the like. In addition to having excellent corrosion resistance, there are advantages such as less surface adsorption of water molecules harmful to the process and good desorption characteristics.

Next, the results of experiments on the degassing characteristics of the passivation film will be described. This experiment was conducted, for example, on a pipe having a total length of 2 m and a diameter of 3/8 inch. FIG. 12 shows the configuration of the experimental apparatus. That is, the Ar gas passed through the gas purifier 601 is passed through a SUS pipe 602 serving as a sample at a flow rate of 1.2 l / min, and the amount of water contained in the gas is measured by an APIMS (atmospheric pressure ionization mass analyzer) 603.
Measured by

FIG. 13 is a graph showing the result of barge in the pipe at normal temperature. The types of pipes used in the experiments were those obtained by electropolishing the inner surface of the pipe (hereinafter referred to as sample A), those subjected to passivation treatment with nitric acid after electropolishing (hereinafter referred to as sample B), and those passivated by oxidation treatment. (Hereinafter referred to as sample C). In FIG. 13, samples A, B, and
This is indicated by the line C. Each pipe has a relative humidity of 50%,
This is left in a clean room at a temperature of 20 ° C. for about one week, and then the experiment is performed.

As is apparent from FIG. 13, it is understood that a large amount of water was detected in both the electropolishing tube in the case of sample A and the electropolishing tube in the case of sample B which was passivated with nitric acid. it can. Even after passing the gas for about 1 hour, 68 ppb of water was detected in the electropolishing tube of sample A and 36 ppb of water was detected in the electropolishing tube of the other sample B. Even after 2 hours, the water content of both samples A and B was low. It is 41 ppb and 27 ppb for the polishing tube, respectively, and it can be understood that the water content is hardly reduced. On the other hand, in the polishing tube of Sample C using the passivation film formed by the oxidation treatment, the water content was reduced to 7 ppb 5 minutes after passing the gas, and the background level was reduced to 3 ppb or less after 15 minutes. I will. Thus, it can be understood that the sample C tube has extremely excellent adsorption gas desorption characteristics.

Next, the test pipe 602 is connected to the power supply 60.
Heating is carried out by 4 and the temperature of the pipe is changed in accordance with the temperature rise time chart shown in FIG. Table 1 shows the average amount of water released when the temperature was changed from room temperature to 120 ° C, from 120 ° C to 200 ° C, and from 200 ° C to 300 ° C. As is clear from these results, it can be understood that the surface of the stainless steel subjected to the oxidation treatment releases less water by about one digit than that of the other stainless steel. This means that the amount of adsorbed water is small and that water can be easily desorbed, indicating that it is optimal for supplying ultra-high purity gas.

The above description is based on the case where S is subjected to passivation treatment by oxidation.
Although the US pipe has been described, similar excellent characteristics can be obtained for the inner surface treatment of the vacuum chamber. That is,
The vacuum chamber of this apparatus (for example, 101a, 104, 1)
08a), after baking, 10 ^-11 ~
It can be understood that a degree of vacuum of 10 ⁻¹² Torr has been realized, and that the device has extremely excellent characteristics as an ultrahigh vacuum device.

Next, an oxide film obtained by oxidizing the stainless steel surface will be described. Table 2 shows SUS316L,
In the case where SUS304L is oxidized with ultra-high purity oxygen, the thickness and refractive index of an oxide film formed on the surface are shown as a relationship between the oxidation temperature and time. Thus, it can be understood that the oxide film thickness does not depend on time, but is determined only by the temperature. This suggests that SUS oxidation proceeds in a process described by the Cabrera and Mott model. That is, if the temperature is controlled to be constant, the oxide film grows to a desired thickness, so that a dense oxide film having a uniform thickness and no pinholes can be formed.

[0050]

[Table 1]

[0051]

[Table 2] FIG. 15 shows that after oxidizing SUS316L at 500 ° C. for about 1 hour, the surface element distribution was measured by ESCA (Electron Spectrosc
4 is a graph showing the results of a study performed using an “opy for Chemical Analysis”. The concentration of Fe is high near the surface, and C
It can be seen that the concentration of r is high.

This means that the oxide of Fe near the surface is
This indicates that a Cr oxide is formed near the interface between the oxide film and the SUS substrate to form a two-layer structure. In addition, as a result of the energy analysis of the ESCA spectrum, a chemical shift due to oxide formation was observed in Fe near the surface, which disappeared in a deep portion, and a chemical shift due to oxide formation was observed only in Cr in a deep portion. It is confirmed. The formation of such a dense two-layer film is considered to contribute to the fact that the present device has corrosion resistance and adsorption gas desorption characteristics. Although a film having a thickness of about 10 nm is used here, the same effect can be obtained even when the film thickness is 5 nm or more. However, if the film thickness is less than 5 nm, pinholes are generated and the corrosion resistance deteriorates, so the film thickness is preferably 5 nm or more.

To form a dense oxide film, use SU
It is important to remove the deteriorated layer and flatten the surface when processing the S surface. In this embodiment, a surface roughness Rmax of 0.1 to 0.7 μm is used, but as a result of the experiment, the maximum value of the difference between the heights of the convex portions and the concave portions within the circumference of a radius of 5 μm is obtained. It has been found that up to about 1 μm, a sufficiently good passivation film is formed.

By performing the above-described passivation treatment, it is possible to cope with an ultra-high vacuum chamber and to sufficiently withstand corrosive gases. This allows
For example, for cleaning the inside of the chamber, it is also possible to remove the deposit of the reaction product attached to the wall surface by increasing the temperature of the chamber and flowing a chlorine-based gas.
Since the inner surface of the chamber is flat and a dense passivation film is provided, the adhesive force of the attached matter is extremely weak, which also facilitates the gas etching. When such cleaning is unnecessary, it is effective to use, for example, a chamber made of an aluminum alloy which is lightweight and suitable for ultra-high vacuum. It should be noted that the target material is also sufficiently purified to have ultra-high purity by removing impurities, and then gas components such as oxygen are removed by vacuum melting.

Next, the wafer holder 107a shown in FIG. 5 will be described. The entirety of the holder 107a is a bellows 40.
It is supported on the outer wall of the chamber via 3 and can move up and down. The silicon wafer 404 is moved up and down with the silicon wafer 404 adsorbed on the electrostatic chuck electrode 405, and the wafer is put in and out of the process chamber 101a. For example, when a wafer is loaded into the process chamber, the entire wafer holder 107a rises and a sealing member (O-ring)
The airtight seal between the process chamber 101a and the transport chamber 104 is formed at the same time by pressing the 406 against the flange surface 407 of the chamber. Although the case where the O-ring is used as the sealing material is shown here, it is more effective to use a metal seal with less degassing.

In this case, it is preferable to use a metal seal that retains elasticity for many attachment / detachment operations and has excellent sealing properties. For example, FIG.
As shown in (b), for example, Al, Ni, SUS3 which expands and contracts an elastic O-ring 1001 within a range of elasticity (that is, within a range where plastic deformation does not occur).
It is effective to use a 16L, Ni-coated stainless steel or other metal leaf spring-like ring 1002. In this case, the sealing surface is a metal surface (this surface is Rmax
(If the mirror surface is 0.2 μm or less, the leak can be further reduced.) The contact pressure is maintained by the O-ring 1001, and the excellent airtightness is maintained. Not only can it be obtained, but it can be used repeatedly.

The open portion 1003 of the leaf spring-shaped ring 1002 is preferably provided on the side where the degree of vacuum is low. Further, if the O-ring 1001 is provided with a notch for communicating the inside 1004 and the open portion 1003, the inside
This is more preferable because it is possible to prevent the gas from staying in the gas reservoir 04. Since the notch is crushed when the ring 1002 is pressed, the inside 1004 is sealed. In this case, a hole communicating with the inside 1004 may be provided in the ring 1002.

As a modification of FIGS. 16A and 16B, FIG.
6 (c) and 6 (d) may be used. In FIG. 16C, two plates are welded at their ends to form a leaf spring, and a contact portion with a flange surface is flattened. This contact surface is preferably in a mirror state of Rmax 0.2 μm or less. Further, FIG.
Is made by welding both ends of the plate together to form a leaf spring-shaped ring 100.
This is an example in which the inside of No. 2 is sealed. This configuration is more preferable because gas emission from the O-ring 1001 to the outside can be prevented.

When the wafer holder 107a is waiting in the transport chamber, the gate valve 105
The opening a is sealed by a, and the airtightness between the process chamber and the transport chamber is maintained.

In this case, the O-ring 408 shown in FIG. 5 may be used for the seal, but a seal using a metal ring 1002 shown in FIG. 16 is more effective. There is no problem even if other sealing methods are used, provided that sufficient airtightness is maintained.

When vacuum sealing is performed by a sealing member made of an elastic material, for example, in FIG. 5, the relative positional relationship between the flange surface 407 and the flange surface 406 ′ is as follows.
It is determined independently of the seal component 406.

That is, the two flange surfaces 407, 40
The relative position of 6 'is a seal part (O-ring) 4
Since it is not determined by the force of crushing 06, FIG.
As shown in an enlarged view, a stopper 4201 that does not deform is interposed, so that the relative positional relationship is always constant. In this case, the O-ring 406 is always compressed with a constant force, and stable sealing characteristics can be obtained. Of course, instead of O-ring 406, FIG.
The same applies when a metal ring such as 6 is used. The stopper 4201 described here may be formed directly at the time of processing the flange surface (407 or 406 '), or a ring-shaped member may be attached later. In order to prevent a dead zone from being formed on the high vacuum side, the stopper 4201 is mounted so as to face the side with a low degree of vacuum.

Further, a vertical guide is provided on the vertically moving flange surface 406 ′ to prevent a lateral displacement when the O-ring 406 is compressed.

Reference numeral 405 denotes an electrostatic chuck electrode for holding a wafer, which is made of, for example, a metal such as stainless steel, Mo or Ti, and has an insulating film 409 formed on its surface. The insulating film 409 is made of, for example, Al ₂ O ₃ , Al
An N film is formed on the electrode surface by plasma spraying, and the surface is flattened by polishing. The thickness of the coating is, for example, about 10 to 100 μm.

By applying a potential difference of, for example, several hundred volts between the electrode 405 and the wafer 404 configured as described above, the wafer can be attracted to the wafer holder with a force of 1 kg / cm ² or more. Normally, when a wafer is simply placed on a stage in a vacuum, the contact between the wafer and the stage becomes a so-called three-point contact, and sufficient surface contact is not made. If a suitable suction means is used, the wafer is suctioned to the stage in a sufficient surface contact state and with a strong force, so that the temperature control of the wafer can be performed extremely accurately. Although a potential is applied to the wafer via the metal electrode 410, the wafer is insulated from both the metal electrode 410 and the electrode 405 and connected to a power supply outside the system.

In FIG. 5, the potential of the wafer is applied from the center of the wafer via the electrode 410.
The configuration may be such that the voltage is applied from the peripheral portion of the wafer. In the case where the voltage is applied from the peripheral portion, there is an advantage that in-plane uniformity is more easily achieved in controlling the temperature of the wafer than in the case where a hole is opened in the center of the wafer holder as shown in FIG. The entire electrode 405 is electrically insulated from the chamber via the insulator 411. Frequency f _W from the outside via the introduction electrode 412 further electrode 405
Of high frequency power is supplied.

FIG. 6 shows an example of the connection relationship between the electrode 405, the wafer 404, and an external power supply. In FIG. 6, the same components as those in FIG. 5 are denoted by the same reference numerals. Reference numeral 4101 denotes a DC power supply for the electrostatic chuck, which is a high-frequency filter 4 that cuts off high frequency and supplies only DC potential.
The electrostatic chuck electrode 405 and the wafer 404 via the
, A DC potential difference V _C is applied. The 4103 is a RF power of the frequency f _W, for example 100 MHz, a high frequency wafer power is supplied by the input electrode 412 via a matching circuit 4101, a blocking capacitor 4105. The output of the high-frequency power supply 4103 is, for example, several W
The wafer 404 is changed in the range of
Can be set to a predetermined value.
Alternatively, the DC potential of the wafer can be changed by changing the matching condition of matching circuit 4104.

When the surface of the wafer is covered with an insulating film such as SiO ₂ , the DC potential on the surface is substantially the same as the potential of the wafer. This is because the capacitance of the capacitor formed by the SiO ₂ film is
This is because the self-bias due to the high frequency almost appears at both ends of the capacitor because it is much larger than that of the capacitor 105.

Therefore, the potential of the wafer is monitored by a voltmeter through a high-frequency filter, and this is fed back to the controller of the RF power supply or the controller of the matching circuit, so that the DC potential on the wafer surface can be accurately controlled to a constant value. can do. The energy of ions entering the wafer surface from the plasma can be accurately controlled to a desired value by the thus set wafer potential. On the other hand, since a high frequency of a different frequency f _T (for example, 13.56 MHz) is given to the target, the wafer is swung at the frequency f _T by capacitive coupling between the target holder electrode 401 and the wafer holder electrode 405.

The circuit 4106 is a circuit that maintains a sufficiently high impedance with respect to the frequency f _W and short-circuits the high frequency of the frequency f _T , whereby the DC potential of the wafer is controlled only by the high frequency of the frequency f _W applied to the wafer holder. Be controlled. This circuit uses, for example, a parallel resonance circuit of L and C, and if 2πf _W = 1 / (LC) ^1/2 , it is open only to the high frequency of f _W ,
If C is set sufficiently large for other frequencies, a short circuit occurs and a desired function can be obtained. Since a certain DC potential must be generated in the wafer holder 405, a capacitor having a sufficiently large capacity is connected in series to the LC parallel circuit.

When a conductive thin film is formed on the wafer surface and the thin film is electrically connected to the wafer,
The potential of the wafer may be directly controlled by a DC power supply. In such a case, for example, the switch 4107 is turned on, and the potential of the wafer is
The potential on the wafer surface can be controlled.

In FIG. 5, reference numeral 413 denotes a heater, which is used to heat the electrode 405 of the wafer holder to a predetermined temperature by flowing a current. In this case, the wafer 4
Since the electrode 04 is attracted to the electrode 405 with a strong force by an electrostatic chuck, it can be uniformly heated to the same temperature as the electrode, and the wafer temperature can be accurately controlled. Reference numeral 414 denotes a fiber thermometer that measures the temperature by extracting light emitted from blackbody radiation through an optical fiber, and can accurately measure the temperature without being affected by noise such as RF. By feeding back the measurement result to the heater controller, accurate temperature control can be performed.

Although only a heating method using a heater has been described here, discharge heating may be performed by, for example, a large number of plasma torches, and more precise control of the temperature distribution may be performed by controlling each discharge current.

In the case of this apparatus, the process chamber 102a
It is possible to prevent intrusion of what is considered to be a contamination source, such as a wafer transfer mechanism, a wafer heating mechanism, and the like, into the inside. Accordingly, the inside of the process chamber 101a and the like is kept highly clean, and a high-quality thin film can be formed. Furthermore, since the heating mechanism is separated from the vacuum system and is kept in the atmosphere or at normal pressure, there is no need to worry about the occurrence of contamination, and it also facilitates uniform heating of the object to be heated. .

Next, the target holder electrode 401 will be described with reference to FIG. 415 is a holder electrode,
It is made of a metal such as stainless steel, Ti or Mo, and its surface is covered with an insulating thin film such as Al ₂ O ₃ , AlN or SiO ₂ . The metal target 109a is
A potential is applied from the back surface via the, and is held by electrostatic attraction due to a potential difference generated between the holder electrode 415 and the holder electrode 415. A bellows 420 made of an insulating material electrically insulates the holder electrode 415 from the chamber 101a.

The other mechanism of the target holder electrode 401 is the same as that of the above-described wafer holder 107a, and a duplicate description will be omitted. 417 is a magnet for magnetron discharge, and 418 is a pipe for flowing a coolant for cooling the target. Reference numeral 419 denotes a ground shield for preventing the target holder electrode 401 from being sputtered. The ground shield can be omitted when the diameter of the target 109a is larger than the diameter of the holder electrode 415. Although this ground shield 419 was not mentioned in the description of the wafer holder 107a, it can be similarly applied to the wafer holder 107a. Also, this target holder electrode 4
01 is the same as the wafer holder 107a.
0 can be moved up and down.

When the target is replaced, the entire target holder electrode 401 rises while contracting the bellows 420, and a gate valve (not shown) closes the opening as in the case of the wafer holder 107a. Then, the target 109a is exchanged by a mechanism as shown in FIG. 17, for example.

FIG. 17A shows a disk-shaped target stocker 1105 for holding, for example, three targets 1101, 1102, and 1103. The target stocker 1105 has a cutout 1104 in a part thereof.

FIG. 17B shows a cross section taken along line XX ′ of FIG.
For example, when the target 1102 on the target stocker 1105 is mounted, the target stocker 11
05 is rotated around a rotation axis 1106 to move the target 1102 directly below the holder electrode 415. Next, the holder electrode 415 is lowered, and the target 1102 is electrostatically attracted to the target holder electrode 401. In this case, since the holder electrode 415 can be moved only in the vertical direction, in order to accurately match the lower surface of the holder electrode 415 with the upper surface of the target 1102, for example, a leaf spring 1107
Is arranged in a concave groove formed on the target stocker 1105, and the target 110 of the target holder electrode 401 is
2, the upper surface 110 of the target 1102
2 ′ makes uniform surface contact with the lower surface of the target holder electrode 401.

In the case where the leaf spring 1107 comes into contact with the surface of the target 1102 and particles are generated due to the sliding contact and contamination of the surface of the target 1102 becomes a problem, FIG.
Take measures as shown in FIG. 7 (d). That is, a pedestal 1191 made of, for example, a non-metallic material is provided in the concave groove of the target stocker 1105 via a coil spring 1190 that expands and contracts in the vertical direction, and the target 1102 is placed on the pedestal 1191.

The holder electrode 415 that has absorbed the target 1102 is raised again, and then the target stocker 1105 is rotated so that the cutout 1104 is located immediately below the holder electrode 415. Thereby, the holder electrode 4
15 is movable downward through the notch 1104, and the target 10 is placed in the process chamber 101a.
9a is faced and the arrangement is as shown in FIG.

Needless to say, such a target load lock exchange mechanism can be used in a manner other than the metal thin film sputtering chamber shown in FIG.

When the target 1103 is, for example, an insulator, a conductive material 1108 such as a metal may be attached to the back surface as shown in FIG. The conductive material may be a metal plate or a metal thin film formed by sputtering.

The target stocker does not need to be in the shape of a disk, but may be in the shape of a long plate. In the case of this long plate, the target is arranged on the plate surface in the longitudinal direction of the plate, and
A configuration that can be slid left and right, back and forth, and the like may be used. The target stocker is provided in each of the process chambers (10
1a to 101d) may be separately provided,
Alternatively, the target chambers 108a to 108d may all be one common chamber, and a common stocker may be provided. In addition to holding the target in the target stocker by simply placing it by its own weight as shown in FIG. 17, an electrostatic chuck or mechanical holding means may be used. In particular, when the latter holding method is adopted, for example, the target 1 shown in FIG.
It is appropriate to set the vertical position of the wafer 09a and the wafer 106a.

Since the temperature during the sputtering rises sharply, the target 1012 has a cooling pipe 4 as shown in FIG.
18 forcibly cools from the back side of the target holder electrode 401.

In FIG. 6, an electrode 415 of the electrostatic chuck is shown.
The potential difference between the high frequency filter 41
The power supply is provided by a DC power supply 4109 connected through the power supply circuit 02. Although the potential of the target 109a is directly supplied by the electrode 4110 and a contact is made at the center in FIG. 6, it may be taken from the periphery of the target 109a, for example. The power supply 4109 preferably employs a method such as using a battery as a backup in order to prevent the target 109a from dropping in the event of a power failure or the like. The DC potential of the target 109a is
However, when the target 109a is made of a metal material, for example, the switch 4 may be used.
It is also effective to close the 111 and connect the DC power supply 4112, thereby controlling the potential. 4116 is a circuit 41
06 is a circuit having the same function as that of the RF power supply 4113.
The circuit is open only for the frequency f _{T of this example} , and is almost grounded for other frequencies, but is open for DC.

The power of the high-frequency power supply (output frequency f _W ) for controlling the potential of the wafer is usually small, and the circuit 411
6 need not always be provided. Usually, the power supply 4113 is, for example, a high-frequency power supply generating an output frequency of 13.56 MHz, but it is preferable to use a power supply having a lower frequency than the output frequency of the RF power supply 4103 connected to the wafer. This is to generate a large self-bias on the target 109a compared to the wafer and to obtain a large sputtering rate. However, when the target potential is controlled by the DC power supply 4112, the magnitude relationship between the frequencies may be reversed.

FIG. 18 shows 14 MHz, 40 MHz, and 10 MHz.
Shows the current-voltage characteristics of the target for three different frequencies of 0 MHz, the experimental data the switch 4111 by plotting the value of the current flowing through the DC power supply 4112 as a function of the closed voltage V _T in FIG. In FIG. 18, the point where the current value becomes 0 (intersection with the horizontal axis) corresponds to the self-bias value, that is, the potential of the target that appears when the switch 4111 is opened. Also, as is clear from FIG. 18, the self-bias value is reduced by increasing the frequency.

Therefore, in the apparatus of this embodiment, the sputtering speed is increased by using a low-frequency (f _T ) RF power source on the target side, and the wafer bias is increased by using the high-frequency (f _W ) RF on the wafer side. To reduce the damage to the wafer substrate and to control the quality of the thin film to be formed. The control of the film quality of the actual thin film will be described later. In this embodiment, f _T =
13.56 MHz, but the f _W = 100 MHz, which is because it is an example, may be a combination of other frequencies.

Further, an electrostatic chuck type target holder shown in FIG. 7 may be used. That is, FIG.
In the configuration of, the RF power is input to the target holder electrode 415 by capacitive coupling with the thin insulating film 409 interposed therebetween, while the DC power supply 4109 is input alone to the target holder electrode 415 via the high frequency filter 4102. If such a suction means is used, it is possible to prevent a large DC voltage from being applied to the capacitor used for the circuit 4116, and the reliability is improved. The same configuration can be applied to the above-described wafer holder.

In the above description, the case where the potential of the target or the wafer is controlled by the DC power supply has been described. However, the case where the control is performed without using the DC power supply will be described with reference to FIG.

In the case shown in FIG. 9A, the LC circuit is set so as to satisfy the condition of 2πf _W = 1 / (L ₁ C ₁ ) ^1/2 2πf _T = 1 / (L ₂ C ₂ ) ^1/2 The impedance for the frequency f _W viewed from the wafer side is 0, that is, short-circuited for the frequency f _W , while the impedance for the frequency f _T viewed from the target side is 0, ie, short-circuited for the frequency f _T. And Therefore, for example, if the frequency f _T is selected to be 13.56 MHz, the frequency 1
It is possible to prevent 3.56 MHz from being superimposed on the wafer, and to accurately control the energy of ions hitting the wafer. The LC circuit is shown in FIG.
It is preferable to provide them symmetrically as shown in FIG.

Next, as another means for holding the target, a method for performing suction by magnetic force will be described with reference to FIG.

As shown in FIG. 19A, reference numeral 1301 denotes a target, on its back surface, for example, iron, nickel,
A thin plate 1302 made of chrome or the like is attached. 13
Reference numeral 03 denotes a magnet, which attracts the thin plate 1302 by this magnetic force, and thereby causes the target 1301 to be attracted to the target holder 1304. Target 1301 and thin plate 1
302 may be screwed from the back of the thin plate, for example. In this case, since the screw material does not protrude from the target surface, the problem of contamination in the chamber 101a can be avoided.
Further, the magnet 1303 may also serve as the magnet 417 (see FIG. 5) for magnetron discharge. The magnet may be a permanent magnet, but may be an electromagnet for facilitating attachment / detachment of the target 1301, and the target may be attached / detached remotely by turning on / off the excitation current.

On the other hand, as shown in FIG. 19B, instead of attaching the thin plate 1302 to the back surface of the target 1301, for example, a permanent magnet 1305 is directly attached, and the permanent magnet 1305 is attached to the permanent magnet 1305 on the back surface of the holder 1304. Adsorption may be performed by magnetic force between them. A mechanism such as a shutter for the target may be provided in the sputtering chamber, but such a mechanism is not essential in the present apparatus. That is, since the entire apparatus can cope with an ultra-high vacuum state, and since an ultra-high purity gas is used, it is not necessary to frequently clean the target surface.

When the above-described mechanism is required, the operation may be performed with the gate valve 105a closed. Further, since the surface contaminant layer is an extremely small amount of moisture adsorption layer, the output of the RF power supply 4113 may be sufficiently reduced and the surface may be sputtered with a bias value equal to or lower than the sputtering threshold of the target 109a. Material is not unnecessarily deposited on the inner surface of the chamber.

Next, the configuration of the cleaning chamber 101c will be described in detail. Since the basic structure is the same as that of the metal thin film forming chamber 101a, it will be described with reference to FIGS.

In this case, for example, as the material of the target 109a, a material such as Al ₂ O ₃ , SiO ₂ , Si ₃ N ₄ , AlN, which has a relatively large threshold value at which sputtering occurs, is used. Further, an RF power supply 411 applied to the target 109a
The frequency of 3 may be larger than 13.56 MHz used for the metal thin film, for example, 100 MHz. In this case, the self-bias value is set to about 10 to 20 V, and a higher frequency, for example, 200 MHz or higher is used to generate high-density plasma. In order to precisely control the potential of the wafer, a measure is taken so that the potential of the wafer susceptor is not affected by the high frequency entering the target side. That is, the frequency f _T
And f _W are set so as not to be an integral multiple.

Therefore, if f _T = 100 MHz, for example, f _W
= 210 MHz. In this case, the target 109a
High density Ar ions without sputtering. The Ar ions thus obtained are irradiated on the surface of the wafer 404 placed on the wafer holder 405. The irradiation energy of this Ar ion is RF
It is determined by the self-bias generated on the wafer by the power supply 4103. Cleaning is mainly performed on an extremely thin natural oxide film layer or an adsorbed molecular layer, particularly a water adsorbed molecular layer formed on the surface of silicon or other materials, and is several eV to 30 e at most.
An Ar particle having a kinetic energy of about V is irradiated.

Therefore, it is necessary to adjust the RF power supply 4103 and the matching circuit 4104 so that the self-bias value generated on the wafer is about several volts to about 30 volts. In order to generate such a relatively small self-bias value with good controllability, the frequency of the RF power supply 4103 is set to a large value, for example, 10
0 MHz may be used. Of course, a frequency of 200 MHz or higher may be used, but the target frequency f _T
A different value is used to prevent interference between the target and the wafer. That is, the DC potentials of the target and the wafer can be independently controlled to optimal values.

Although the description has been given only of the case where the material of the target 109a is an insulator, the self-bias value is set to a sufficiently low value that does not cause sputtering even if the material has conductivity such as Si. Anything that can do it is acceptable. When it is not necessary to frequently exchange the target with the target 109a, the target load lock exchange mechanism may not be necessarily provided.

The gas used may be Ar, but H ₂ , H
A gas such as e may be used. In particular, when cleaning is performed using a gas to which H ₂ is added based on Ar gas, the molecular layer of water adsorbed is removed by irradiating Ar ions, and the carbon atoms adsorbed on the Si surface are also effective with H ions. Can be removed. Even if a slight amount of impurity molecules such as H ₂ O and O ₂ are mixed in the gas, the surface will be contaminated.
04 (see FIG. 10). For example, when the gas system to be used is not sufficiently considered and contains a small amount of impurity molecules such as H ₂ O and O ₂ , for example, 1 to 30% of H ₂ is added to Ar gas. Is valid. This is because oxygen radicals generated in the plasma atmosphere combine with H before reacting with the sample surface.

The addition of the H ₂ gas as described above is not limited to the cleaning chamber 101c, but may be applied to the cleaning chambers 101a and 101a.
Needless to say, the same effect is obtained in a chamber for forming a thin film such as b.

The cleaning chamber 101c has a function of irradiating the sample surface with ions having a small kinetic energy of about several eV to about 30 eV, and is provided for obtaining a good interface when forming a multilayer thin film structure. Have been. Irradiation ions have low energy and do not damage the underlying substrate. In particular, this cleaning does not need to raise the temperature of the substrate, and can be performed at normal temperature. Therefore, the heater 413 may not be provided.

The RF power supply 4103 is connected to the wafer susceptor.
Has been described as an example, but in order to more accurately control the energy of Ar ions, the circuit shown in FIG. 9A is preferably used. That is, 2πf _T =
The values of L and C are selected so that 1 / (LC) ^1/2 (f _T is the frequency of the RF power supply applied to the target). In this way, the LC circuit is in a parallel resonance state, and when the earth 4203 is viewed from the wafer holder 4201, the impedance becomes infinite, and the potential of the wafer approaches the potential of the plasma without limit. That is, A for irradiating the wafer
The energy of the r ion approaches zero. Therefore, if the values of L and C are slightly shifted from the values satisfying the above conditions, the energy of Ar ions can be accurately controlled even in the range of 0 to 5 eV.

The effect of using the cleaning chamber 101c will be described later with reference to experimental data.

Next, the oxidation chamber 101d will be described. The basic configuration of the oxidation chamber 101d is the same as that of the metal thin film chamber 101a, and will be described with reference to FIGS. 5, 6, and 10 described above. This chamber 1
An ultrapure argon and oxygen gas can be introduced into 01d from the gas supply system 504. For example, when oxidizing Al, the wafer is heated using the heater 413 and the temperature of the wafer is set to, for example, 100 ° C. to 450 ° C.
It can be set to any value in the range of ° C.

A silicon wafer 4 having an Al film formed on its surface
04 is heated to, for example, 400 ° C. for about 1 hour in a high-purity oxygen gas atmosphere, so that about 3 nm of Al ₂ O ₃
The thin film can be formed by direct thermal oxidation of Al.
This film thickness does not increase even if the oxidation time is lengthened and shows a substantially constant value. In the direct oxidation of Al, an oxygen gas may be first introduced into the chamber 101d and the temperature of the wafer may be increased at atmospheric pressure, or the temperature may be first increased in a vacuum and then an oxygen gas may be introduced. The pressure of oxygen may be lower than the atmospheric pressure, or may be higher than the atmospheric pressure. Oxidation under a reduced pressure atmosphere may be performed by evacuating by using the vacuum exhaust device 501 in FIG. 10 while flowing O ₂ gas to adjust the pressure of oxygen, or may be diluted with Ar gas, for example. Further, before being oxidized with oxygen, it is applied in a vacuum atmosphere or an Ar atmosphere for about 30 minutes,
Annealing is preferably performed at a temperature of about. This is because Al gas of about several ppm is contained in the Al thin film formed by sputtering, and it is better to perform thermal deoxidization of Al after performing this degassing in order to release this from the film. This is because a high-quality oxide film can be obtained.

A target 109a (FIG. 5) provided in the oxidation chamber 101d, a high-frequency power supply 4113 connected to the target holder electrode 401, a high-frequency power supply connected to the wafer holder (4103, etc.)
4104) is not essential. For example, when the thickness of the Al ₂ O ₃ layer is required to be larger, for example, 5 nm or more, a target of Al ₂ O ₃ is used as the target 109a, 13.56 MHz is used as 4113, and a high frequency power supply of 100 to 200 MHz is used as 4103. Is used. A thick film can be obtained by forming Al ₂ O ₃ by sputtering on Al ₂ O ₃ thus formed by thermal oxidation. In addition, by applying a bias to the wafer holder (107a in FIG. 5) using, for example, a high-frequency power supply 4103 of 100 to 200 MHz, an Al ₂ O ₃ film having good dense characteristics can be formed. In this case, since the interface between Al ₂ O ₃ and the thin Al is an interface formed by thermal oxidation, the conventional Al ₂ O ₃
Is an interface having more stable characteristics than an interface formed only by sputtering.

Next, the sputtering chamber 101 for the insulating thin film is used.
b will be described. The basic configuration of this chamber is also 1
Since it is the same as the metal thin film sputtering chamber 01a, description will be made with reference to FIGS.
The chamber 101b and the sputtering chamber 1 for a metal thin film
The difference from 01a is that the material of the target 109b is an insulator. Therefore, when an electrostatic chuck type holder is used, Al, Al as shown in FIG.
A conductive material such as Mo or W is attached. In this case, since the bias cannot be controlled by the DC power supplies 4108 and 4112,
4112 becomes unnecessary. However, if a target exchange mechanism as shown in FIG. 17 is provided so that the insulator target and the metal target can be exchanged, metal sputter deposition can be performed. In this case, the DC power supply 410
8, 4112 can be used for bias control. That is, the switches 4107 and 4111 are opened and closed according to the application.

Next, a method for loading and unloading a wafer between the four chambers without changing the reduced pressure state will be described. In this case, for example, FIG.
A transport mechanism as shown in FIG. Reference numeral 508 denotes a wafer holder which transports the wafer surface by suctioning the wafer surface at a peripheral portion by an electrostatic chuck 509. The arm 510 moves up and down the electrostatic chuck at a required position, and is fixed to the transport vehicle 511, and freely reciprocates in the transport chamber 104 together with the transport vehicle. Further, the transfer vehicle 511 has a loading chamber 102 and an unloading chamber when a wafer is taken in and out of the apparatus.
It moves also in 103. This carrier has a track 51, for example.
It is desirable to use a linear motor car that moves at a high speed while magnetically levitating on the upper surface 2. That is, it is preferable to adopt a structure having no mechanically sliding portion when moving. Of course, as long as sufficient measures against dust generation are taken, a transport vehicle of a type that operates on wheels on wheels may be used.

It is to be noted that, while the transport chamber 104 is pulled by the vacuum pump, Ar is changed from several tens sccm to several tens sccm.
Flow 0 sccm into the transport chamber 104 and
0 ^-2 to 10 ^-8 Torr (preferably 10 ^-3 to 10 ^-4 Torr)
The pressure in the transport chamber 104 is reduced to about rr).
May be carried out. With this configuration, the frictional force generated in the transport vehicle is reduced by Ar.

In the above-described apparatus for performing single-wafer processing of wafers, high-speed processing is required in which the time allowed to perform one processing on one wafer is, for example, one minute or less. For this reason, it is necessary to shorten the opening and closing time of the wafer into and out of the process chamber 101a, as well as to speed up the opening and closing of the gate valve 105a. Also, in FIG.
02, the detailed structure of the unloading chamber 103 is not shown, but this chamber has a wafer cassette for storing several tens of wafers, and is equipped with a transfer mechanism to the electrostatic chuck transfer mechanism 114 and the like. I have. In such a delivery as well, high speed opening and closing of the gate valves 105e, 105f and the like is similarly required.

Next, a gate valve according to the present invention will be described.
This will be described with reference to FIGS. 20 and 21A.

FIG. 20A corresponds to, for example, a state in which the gate between the process chamber 101a and the transport chamber 104 is closed. 1401 is made of, for example, Ti, has a thickness of about 0.2 to 0.5 mm and a very small mass. For example, a mechanism as shown in FIG. 20B is used as a driving unit for giving the thin plate 1401 an opening / closing operation. FIG. 20B is a view of the gate valve of FIG.
02, 1402 'and are supported at two points 1403, 1403'. 1404 and 1404 'are pins for pivotally connecting the arm to the chamber.
The arm 1402 rotates about 1404 'as a fulcrum. That is, by moving the arm 1402, the thin plate 14
01 moves.

In this case, since the thin plate 1401 is selected to have an extremely small mass, the thin plate 1401 can be moved at a high speed by the above simple mechanism. Sheet 14
In order to further reduce the mass of 01, a method of reducing the thickness of Ti to 0.1 mm or less and affixing it to a plastic plate to reinforce may be adopted. Alternatively, by using a reinforced plastic whose surface is coated with a metal material such as Ti, Mo, W, etc., a lightweight and excellent in durability can be obtained. Such a thin plate 1401 does not cause a problem in strength because the inside of both chambers partitioned by the thin plate 1401 has a vacuum degree of at most several Torr.

The material of the thin plate 1401 is not limited to Ti, but may be duralumin or another material. It is preferable that the surface of the thin plate 1401 or the portion 1405 of the sealing flange has a roughness of, for example, Rmax of 0.1 μm or less.

In FIG. 21A, 1406 and 1409
Are insulating plates, one insulating plate 1406 is fixed to the chamber wall 1407, and a metal electrode 1408 is sandwiched between the two insulating plates 1406 and 1409.
08 is connected to one electrode of a DC power supply (not shown),
The other electrode of this DC power supply is connected to thin plate 1401. In this case, by applying a voltage of about several hundred volts between the electrode 1408 and the thin plate 1401, the thin plate 1401 is sucked by electrostatic force, and the vacuum sealing is performed together with the O-ring 1411 by this force. It is preferable to use an elastic material for the electrode 1409.

It should be noted that the gate valve of this embodiment is a thin plate 1
It is assumed that the chambers on both sides sandwiching 401 are always depressurized to several Torr or less. For example, when one chamber is at atmospheric pressure, it is impossible to increase the strength. Instead of, for example, FIG.
1 (b), a mechanically strong gate valve,
That is, a gate plate 1410 having a predetermined thickness is used. Normally, the gate valves 106a to 106d shown in FIG. 1 are used only in a high vacuum state in both chambers. The gate valve as shown in FIG. 21B is necessary only when the inside of the chamber is returned to the atmospheric pressure for maintenance or the like.

The loading chamber and the unloading chamber (102,
103) and the transfer of the wafer between the transport chamber 104 and the transport chamber 104, a gate valve as shown in FIG. 20 may be used. However, when the wafer is taken in and out of the apparatus, both the chambers 102 and 103 need to be returned to the atmospheric pressure. In such a case, a gate valve as shown in FIG. May be used.

Next, an example of use of the above-described apparatus will be described with reference to experimental results.

First, the metal thin film sputtering chamber 101
In a, a case where a thin film is formed on a Si wafer by using a pure Al target 109a will be described.

FIG. 22A is a photograph obtained by observing the surface of the Al thin film thus formed with a Nomarski differential interference microscope. When forming a thin film, N-type (111) Si
A wafer is used. This wafer is first processed in the cleaning chamber 101c. That is, if the frequency f _W is 1
00 to 200 MHz, pressure within chamber 101c 10 ^-2
The surface of the wafer is cleaned by setting the irradiation Ar ion energy to 2 to 5 eV at -10 ^-3 Torr.

Then, a wafer bias of -20 to -40 V is applied to the wafer by the target 101a, and about 5 to 6 or more Ar atoms per Al atom contributing to film formation are irradiated on the wafer surface. It was grown to a thickness of 1 μm. FIG. 22A shows the thin film thus formed.

On the other hand, FIG. 22C shows the surface of an Al thin film formed by a DC magnetron sputtering apparatus.
It can be understood that many fine irregularities appear on the surface as compared with those formed by this apparatus. FIGS. 22B and 22D show
23A and 23B are surface photographs after heat-treating the samples of FIGS. 22A and 22C respectively in a forming gas atmosphere at 400 ° C. for 30 minutes. The surface of a thin film formed by a conventional apparatus (FIG. 22)
Although many hillocks are generated in (d)) and the surface is very rough, no hillocks are generated on the surface of the Al thin film formed by this apparatus (FIG. 22B). The occurrence of hillocks causes various problems in the multilayer Al wiring structure, such as remarkable deterioration of the withstand voltage of the interlayer insulating film and difficulty in fine processing of the wiring. This device enabled the formation of a hillock-free Al thin film for the first time.

FIG. 23 shows a reflected electron beam diffraction pattern of the sample shown in FIG. As is clear from FIG. 23, a black spot with a streak is observed, and it can be understood that a single-crystal Al thin film is formed. Also, according to X-ray diffraction and the like, it has been found that a (111) oriented thin film is formed. In the conventional device,
It is known from reflection electron beam diffraction and X-ray diffraction that a polycrystalline thin film having many plane orientations other than (111) is formed.

By using the present apparatus as described above, (1
11) The growth of a single-crystal thin film of Al having a (111) plane on Si is made possible firstly because the cleaning chamber 101c completely removes the contamination layer on the Si wafer surface without damage, and This is because the Al thin film is grown while irradiating Ar ions having a relatively low kinetic energy of about 40 eV, which is about the same as the bonding energy of atoms in the crystal, in the metal thin film sputtering chamber 101a. That is, when impurities on the surface are removed, Al
Atoms are (111) on the surface based on the periodicity of the Si crystal.
And a single crystal Al thin film grows by the effect of Ar ion irradiation. The interface between the single crystal Al and Si thus formed is very stable thermally. That is, even if heated to 400 to 500 ° C., Al and Si are not mixed with each other and alloyed.

In this case, the alloying at the contact hole portion causes Al to dissolve into the Si substrate and short-circuit the shallow PN junction, which is a so-called spike problem. Alloy wiring is used. The alloy wiring not only has a high resistance, but also causes Si in the alloy to bend out to the contact portion and cause a defective contact having a small dimension. With this apparatus, pure Al can be used for the wiring. And the wiring resistance is 2.8 μΩ · cm, which is lower than the resistance value of the alloy wiring, 3.5 μΩ · cm.

At 77 ° K, the specific resistance value is 0.35 μΩ · cm for pure Al and 0.67 μΩ for alloy wiring.
The difference is much larger than Ω · cm. Further, it is possible to realize the wiring formation of the ultra-highly integrated LSI including the multilayer wiring without the problem of the contact failure due to the Si protrusion in the fine contact.

Next, the properties of the Cu thin film formed using the present thin film forming apparatus will be described. First, (100) Si
After processing the wafer in the cleaning chamber 101c,
In the chamber 101a, a Cu thin film having a thickness of about 1 μm is formed using a Cu target having a purity of 6N as 109a. In this case, the DC bias applied to the wafer 106a is changed from + 10V to -160V.

From the X-ray diffraction pattern of the thin film formed as described above, only peaks (111) and (200) are observed. FIG. 24 shows (111) and (20)
0) represents the height of the diffraction peak as a function of the wafer bias. When the wafer bias is 0 V, (2
Only the peak of (00) appears, indicating that the Cu thin film is a (100) oriented film. That is, the crystal structure reflects the crystallinity of the underlying Si. When the reflection electron beam diffraction pattern of this film is examined, a black spot with a streak is observed, and single crystal Cu grows epitaxially on Si.

As is clear from FIG. 24, when the bias value of the wafer is increased, the peak of (200) decreases and the peak of (111) increases. At a bias value of 50 V or more, a (111) -oriented Cu thin film is obtained. The reflected electron beam diffraction pattern of the thin film at a bias value of −50 V is observed as a Bragg spot with streaks, and it can be understood that (111) Cu is epitaxially grown on Si. The crystallinity of the formed thin film is not determined by the crystal structure of the underlying Si, but is governed by the energy of the irradiated Ar ions.

Conventionally, a technique of forming a single-crystal Cu thin film on Si has not been known, but according to the present apparatus, such a thin film can be formed. The reason is Al
As in the case of single crystal growth, it is considered that the cleaning process of the present apparatus and the ion irradiation with low kinetic energy are used.

The Cu thin film formed on SiO ₂ was processed by the same process as that on the Si wafer.
Examination of the adhesion to iO ₂ yields the following. C
Although it is known that u and SiO ₂ have poor adhesion, this may hinder the use of Cu as wiring for LSI. However, the Cu thin film formed using this apparatus does not peel off any sample under all wafer bias conditions even in the adhesion test using various types of adhesive tapes such as Scotch Tape (registered trademark). . This is because the adsorbed molecular layer of water was completely removed by the surface cleaning process in the cleaning chamber. The specific resistance of the Cu thin film thus formed is about 1.8 μΩ · cm, which is much lower than that of pure Al wiring, which is very advantageous in forming a high-speed LSI wiring.

Next, the characteristics of the Schottky junction between Cu and N-type (100) Si will be described based on the structure shown in FIG. That is, first, the N-type (100) Si layer 1
An SiO ₂ layer 1802 is formed on 801, and a contact hole 1803 is formed. Thereafter, a Cu layer 1804 is formed on the entire surface in accordance with the above-described process, and thereafter, a pattern is formed by using a photolithography technique.
All of these processes are performed at 130 ° C. or lower. FIG. 26 shows the current-voltage characteristics of the Schottky junction thus obtained.
Shown in FIG. 26A shows the result at room temperature, and FIG.
(B) is data at −50 ° C. The coefficient η value obtained from the linear portion of the forward characteristic shows a value close to 1 at 1.03 to 1.05 regardless of the bias condition of the wafer, indicating that ideal diode characteristics are obtained. You.

FIG. 27 is a plot of Schottky barrier height values obtained from these characteristics as a function of substrate bias. Regardless of the bias value, a value substantially equal to the conventionally reported value of 0.58 V is obtained. In forming this sample, Cu was formed at room temperature.
The highest temperature in the thermal process after the formation of the Cu thin film is 130 ° C. in post-baking of the resist during patterning. As described above, in the present cleaning process, ideal Schottky characteristics can be obtained even in a low-temperature process close to room temperature, and ideal metal-semiconductor contact can be realized without any heat treatment step.

FIG. 28 is a reflection electron beam diffraction image of a Si thin film formed on a (100) Si wafer. In this case, the material is prepared by first pre-cleaning (100) Si with an acid, transporting it into the apparatus, performing cleaning in the chamber 101c, and then cleaning the target 109a in the chamber 101a.
A silicon thin film of about 0.5 μm is formed using N-type silicon having a P impurity concentration of 3 × 10 ¹⁸ cm ⁻³ . The temperature of the wafer at this time is 330 to 350 ° C.

FIGS. 28A and 28B are diffraction images of a sample using two different cleaning conditions. FIG.
8A shows the case where the energy of Ar ions for irradiating the wafer surface in the cleaning process is set to about 20 V, and FIG. 28B shows the case where the energy is set to 40 V. In FIG. 28A, a diffraction pattern including a Kikuchi line can be observed, and it can be seen that an epitaxial Si layer having excellent crystallinity is formed. However, FIG.
(B) shows a ring indicating the formation of polycrystalline silicon. As is evident from the result, if the irradiation energy of Ar at the time of cleaning is too large, it damages the substrate and deteriorates the crystallinity. Cause.

Examination of the cleaning conditions by changing the wafer bias shows that the cleaning can be effectively performed without damaging the substrate if the energy of the Ar ions applied to the wafer is set to 30 eV or less. When the concentration of activated P contained in the formed epitaxial Si layer is measured, a value of about 10% of the impurity concentration of the target is obtained. 350 ° C
It can be understood that not only can silicon be epitaxially grown at the following low temperature, but also the activation of impurity atoms having a concentration of approximately 10 ¹⁸ cm ⁻³ is possible.

Next, A was formed using the thin film forming apparatus of the present invention.
l-Al ₂ O ₃ an example of a capacitor of a three-layer structure of -Al per reference to FIG. 4 will be described. Al (304) of the first layer is P
A is formed by connecting to an N ⁺ layer 302 formed on a mold Si substrate 301, and A is formed thereon by thermal oxidation.
An l ₂ O ₃ film 305 and an Al thin film 306 are formed, and this is etched to realize a capacitor structure.

What is important in this structure is that Al ₂ O ₃ is about 3
S such that the film thickness is as thin as nm and the relative dielectric constant is 9.
Since the value is about twice the dielectric constant of iO ₂ , a large capacitance can be realized with a small area. The mechanism of oxidation follows the model of Cabrera and Mott, and it is considered that oxidation proceeds with an oxidizing agent that tunnels through the oxide film by an electric field. For example, when a constant film thickness of 3 nm is formed, the time is increased. No further oxidation proceeds.
Therefore, exposure to an oxidizing atmosphere for a sufficiently long time
A uniform oxide film can be formed over the entire surface of the thin film. Furthermore, since the Al thin film formed while performing ion irradiation in the sputtering chamber 101a does not have any surface irregularities such as hillocks when the temperature is raised as shown in FIG. 22, an extremely flat oxide film is formed on the Al surface. As a result, the concentration of the electric field locally at the convex portion is also widened, and the breakdown voltage of the insulating film is improved.

Further, as is clear from the description of the manufacturing process, since these laminated structures are formed without exposing the interface to the atmosphere, there is no contamination due to adsorption of atmospheric components, and the initial withstand voltage is good. Rather, degradation of the withstand voltage for long-term use, so-called Time dependentbr
Characteristics for eak down also to have better characteristics than the capacitors of the conventional Si-SiO ₂ -Si structure.

In the structure shown in FIG. 4, the Al thin film of the first layer is in contact with the surface of the N ⁺ layer 302 at the contact hole 307. And Al (304), A
A three-layer film of l ₂ O ₃ (305) and Al (306) is formed. Therefore, Al (304) and N ⁺ layer (302)
Will be exposed to the atmosphere, in this case N ⁺
Due to the influence of a natural oxide film or the like formed on the surface of the layer, the contact characteristics often fail, which is one of the factors that reduce the yield and reliability of LSI. However, in this apparatus, since the first layer of Al (304) is formed after the surface is cleaned in the cleaning chamber 101c, such a problem is solved.

In the above example, the case where Al which is the core component of the LSI wiring is used has been described. However, this device can be applied to any metal, and
W, Mo, Ti, Ta, C starting to be used for I wiring
Also applicable to u, Nb. One of the features of the present apparatus is that the metal surface on which the film is formed is extremely flat and the metal film can be formed without generating any hillock even when heat treatment is performed. After the Ta film is formed, if it is oxidized at 400 ° C. to 600 ° C., ₃ to ₅ nm of Ta ₂ O ₅ can be obtained as a dense film.
The dielectric constant of Ta ₂ O ₅ is 22, and a capacitor having a smaller area and a larger capacity can be realized.

FIG. 29 shows a wiring structure formed by a similar process. Reference numeral 2201 denotes a first layer of an Al thin film, which forms a wiring for transmitting a signal. 2203 is Al ₂ O ₃
An Al electrode partially provided through the film 2202, to which a power supply potential or a ground potential is applied. This is a structure in which a capacitor is connected to part of the wiring,
For example, it can be used as a bootstrap capacitor of a dynamic circuit such as a shift register.

The bootstrap capacitor is required to have the same value as the gate capacitance. However, if a dummy MOS transistor is formed and its gate is used as a capacitor, it will occupy a large area on the chip. This is one of the major factors that hinder the improvement of the integration degree of the dynamic circuit. However, using this device, as shown in FIG.
Since a part of the wiring can be used as a capacitance as it is, no extra area is required, and high integration is extremely advantageous. The structure of FIG. 29 is similar to that of FIG.
_{The 2} O ₃ film 2202 and the Al electrode 2203 may be formed. Conversely, after forming the electrode 2203 at a predetermined position, the A
An l ₂ O ₃ film and an Al wiring may be formed. In this case, Al
At the beginning of the formation of the thin film, the surface is exposed to the atmosphere due to the patterning step. However, if the surface is cleaned in the cleaning chamber 101c before the formation of the Al ₂ O ₃ film, good Al—Al ₂ O ₃ An interface can be formed.

In addition, the capacitor having such a configuration has a linear L
It can be used as a capacitor frequently used in SI. As a result, the degree of integration of the linear LSI can be improved.
Further, by using the capacitance of the switch capacitor, it is possible to create a resistance in a small area, and various applications are possible.

Using the present apparatus, the following device can also be manufactured. That is, the cleaning chamber 10
After cleaning the Si surface in 1c, SiO ₂ is formed on the Si surface in a thickness of, for example, about 3 nm in the wiring chamber 101d.
At 1b, a ferroelectric thin film is formed. After forming an SiO ₂ film on the ferroelectric thin film, the chamber 10
1a, the poly-Si—S
iO ₂ - ferroelectric thin film -SiO ₂ -Si a five-layer structure can be realized. If this is formed in a gate pattern and the source and drain are formed by ion implantation or the like, a high-speed nonvolatile memory can be realized. That is, the direction of the spontaneous polarization of the ferroelectric is controlled by the voltage applied to the gate electrode, thereby controlling the ON-OFF state of the MOS device. Thereby, the hot electron injection type EPRO
Data can be rewritten at a higher speed than the M element. Also, using this apparatus, an oxide superconductor thin film (for example, Y
-Ba-Cu-O) can also be formed. That is, after a thin film having a predetermined composition is formed in the chamber 101b, the oxygen concentration is controlled in the oxidation chamber 101d.

As described above, the super LS is realized by this apparatus.
Various multilayer thin film structures required for I can be formed with excellent film quality and interface characteristics at a low temperature. In particular, wiring formation after formation of the collector can be performed at room temperature, including the multilayer wiring structure.

This is because ASIC (Application Specif.
It is very important for applications such as ic IC) because it gives a great degree of freedom. The fact that such a low-temperature process is possible also has the advantage that the degree of freedom is large in the selection of chamber parts, vacuum components and other materials, and that the design and manufacture of the apparatus become easy. In the above description, SiLSI was mainly used, but other compound semiconductors,
It goes without saying that the present invention can be similarly applied to any material such as a quartz substrate.

Although the case where four chambers are combined has been described as a typical example, the combination may be changed or the number may be increased or decreased as needed.

In the above embodiment, the case where the wafer is taken in and out of the various decompression chambers by moving the wafer susceptor (in the case of FIG. 1 up and down) is shown. An embodiment will be described.

In this example, the decompression chambers 101a to 101c are located at positions facing the gate valves 105a to 105c across the transport chamber 104.
A movable arm is provided at the front end, which can move back and forth in the direction of 101c to 101c and has gripping means for gripping the wafer. The movable arm can be transferred from the wafer by the gripping means at the tip thereof.

Next, an example of a wafer transfer procedure in this embodiment will be described with reference to FIG.

First, the wafer 106e to be processed is placed on the wafer holder 107e in the load chamber 102. The loaded wafer 106e is held by the gripping means at the tip of the movable arm 130e, and the movable arm is advanced into the transport chamber 104. Gate valve 105e
Is opened, the movable arm 130e is advanced, and the wafer 10 is
6e. After the delivery, the movable arm 130e retreats, and after retreating, the gate valve 105e is closed.

On the other hand, the transfer vehicle 511 that has received the wafer 106e moves along the track 512 to the cleaning chamber 10.
Move to before 1c. Cleaning chamber 101b
After the stop, the gate valve 105c is opened, the movable arm 130c is advanced, and the wafer on the carrier is gripped.
While holding the wafer, the movable arm 130e is further advanced to transfer the wafer to the wafer holder 107c of the cleaning chamber 101c. After the delivery, the movable arm is retracted, and the gate valve 105c is closed. The transfer of the wafer between the decompression chambers may be performed in the same manner. As described above, the wafer can be transferred without changing the vacuum state.

Although not shown, an exhaust device is connected to the transport chamber 104, each of the decompression chambers 101a to 101c, the load chamber 102, and the unload chamber 103, as in the above embodiment. .

[0158]

According to the first aspect of the present invention, there is provided a gate valve of a thin film forming apparatus configured to be capable of opening and closing an opening formed in a partition partitioning two adjacent decompression chambers. , A driving means for swinging the thin plate in a direction substantially parallel to the plate surface, and a voltage supply means for applying a DC voltage between the thin plate and the partition The opening that connects the two decompression chambers can be quickly opened and closed, and a strong vacuum sealing state of the opening is realized by electrostatic attraction. It can process wafers quickly and smoothly in various thin film types used for manufacturing, without the risk of contamination of the decompression chamber due to dust generation, etc. Can contribute to

According to the invention of claim 2, in the thin plate, at least a plate surface on a side facing the outer peripheral portion of the opening is formed with a surface having a roughness that reduces a coefficient of friction with the outer peripheral portion. Therefore, in addition to the effect of the first aspect of the present invention, the friction between the thin plate and the outer peripheral portion of the opening is reduced, and the work is further facilitated.

[Brief description of the drawings]

FIG. 1 is a system diagram showing an example of a thin film forming apparatus to which a gate valve of the present invention is applied.

FIG. 2 is a sectional view showing a main part of another example of the thin film forming apparatus.

FIG. 3 is a side view showing a positional relationship between a wafer and a target.

FIG. 4 is a schematic view showing a thin film structure.

FIG. 5 is a schematic diagram of a sputtering chamber.

FIG. 6 is a schematic diagram of a sputtering chamber.

FIG. 7 is a schematic diagram of a sputtering chamber.

FIG. 8 is a schematic diagram of a sputtering chamber.

FIG. 9 is a schematic view of a sputtering chamber.

FIG. 10 is a schematic diagram illustrating an example of a connection relationship between a sputtering chamber, a vacuum exhaust device, and a gas supply device.

FIG. 11 is a photomicrograph showing the effect of moisture concentration in gas on surface roughness.

FIG. 12 is a configuration diagram showing an experimental apparatus for degassing characteristics.

FIG. 13 is a graph showing the results of the experiment of FIG.

FIG. 14 is a heating time chart of a pipe.

FIG. 15 is a graph showing an element distribution with respect to a film formation depth.

16A and 16B are a front view and a cross-sectional view illustrating an example of a sealing material.

FIG. 17 is a view for explaining a mechanism indicating replacement of a target.

FIG. 18 is a graph showing current-voltage characteristics of a target with respect to frequency.

FIG. 19 is a conceptual diagram illustrating an example of target holding.

FIG. 20 is a diagram illustrating an example of a high-speed gate valve according to the present invention.

21A is a diagram illustrating an example of a high-speed gate valve according to the present invention, and FIG. 21B is a side view illustrating another example of the gate valve.

FIG. 22 is a micrograph of an Al thin film formed on a Si wafer.

FIG. 23 is an electron beam diffraction photograph.

FIG. 24 is a graph showing the relationship between wafer bias and X-ray intensity in a Cu thin film.

FIG. 25 is a conceptual sectional view of a thin film structure.

26 is a graph showing current and voltage characteristics of a Schottky junction in the structure shown in FIG.

FIG. 27 is a graph showing a relationship between a wafer bias and a height of a Schottky barrier in the structure shown in FIG. 25;

FIG. 28 is a photograph showing a reflected electron beam diffraction image of a (100) Si, Si thin film formed on a wafer.

FIG. 29 is a conceptual sectional view showing a wiring structure.

FIG. 30 is a side view for explaining a conventional gate valve.

[Explanation of symbols]

101a Sputter chamber (process chamber) for forming a metal thin film, 101b Sputter chamber (process chamber) for forming an insulating thin film, 101c Cleaning chamber (process chamber), 101d Oxidation chamber (process chamber), 102 loading chamber, 103 unload chamber , 104 transport chamber, 105a, 105b, 105c, 105d, 105e,
105f Gate valve, 106a, 106c, 106e Wafer, 107a, 107b, 107c, 107d, 107e
Wafer holder, 107f wafer stage, 108a, 108b, 108c, 108d target chamber, 109a, 109b, 109c, 109d target, 110a, 110b, 110c, 110d, 112a,
112b, 112c, 112d tuning circuit, 111a, 111b, 111c, 111d, 113a,
113b, 113c, 113d RF power supply, 114 wafer chuck, 130e movable arm, 301 silicon substrate, 302 N ⁺ layer, 303 insulating film, 304, 306 Al thin film, 305 Al ₂ O ₃ film, 401 target holder electrode, 402 wall material , 403, 420 bellows, 404 wafer, 405 electrostatic chuck electrode, 406 sealing parts (O-ring), 406 ', 407 flange surface, 408 O-ring, 409 coating, 410 metal electrode, 411, 421 insulator, 412 introduction electrode , 413 heater, 414 fiber thermometer, 415 holder electrode, 416 electrode, 417 magnet, 418 pipe, 419 ground shield, 4101, 4108, 4109, 4112 DC power supply, 4102 high frequency filter, 4103 RF power supply, 4104 Matching circuit, 4105 Blocking capacitor, 4106, 4116 circuit, 4107, 4111 switch, 4110 electrode, 4113 RF power supply, 4201 stopper, 4203 ground, 501 Turbo molecular pump (vacuum exhaust device) having magnetically suspended rotor, 502 Rotary pump, 503 oil trap, 501 ′, 502 ′, 503 ′ vacuum pumping system, 504 gas supply device, 505 purge line, 506 valve, 507 mass flow controller, 508 wafer holder, 509 electrostatic chuck, 510 arm, 511 carrier, 512 track, 601 gas purifier, 602 SUS pipe, 603 APIMS (atmospheric pressure ionization mass analyzer), 604 power supply, 1001 O-ring, 1002 leaf spring ring 1003 opening, 1004 inside, 1012, 1101, 1102, 1103 target, 1102 'top of target 1102, 1104 cutout, 1105 target stocker, 1105' concave groove, 1106 rotation axis, 1107 leaf spring, 1108 conductive Material, 1190 coil spring, 1191 cradle, 1301 target, 1302 thin plate, 1303 magnet, 1304 target holder, 1305 permanent magnet, 1401 thin plate, 1402, 1402 '1 pair of arms (driving means), 1404, 1404' pin, 1405 Sealing flange, 1406, 1409 Insulating plate, 1407 Chamber wall, 1408 Metal electrode, 1410, 1410 'Gate plate, 1410 "Connecting board, 1411 O-ring, 1420 Li Click pieces, 1421 coil spring, 1422 bulkhead, 1423 opening, 1424 stoppers, 1441 pivot axis, 1430 and 1431 chamber, Si layers 1801 N-type (100), 1802 SiO ₂ layer, 1803 a contact hole, 1804 Cu layer, 2201 wiring (Al thin film), 2202 Al ₂ O ₃ film, 2203 Al electrode.

──────────────────────────────────────────────────の Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H01L 21/31 B01J 19/08 C23C 14/56 H01L 21/203 H01L 21/205 H01L 21/285

Claims (2)

(57) [Claims] A thin plate formed so as to cover said opening in a gate valve of a thin film forming apparatus configured to be capable of opening and closing an opening formed in a partition partitioning two adjacent decompression chambers. A drive unit for swinging the thin plate in a direction substantially parallel to the plate surface, and a voltage supply unit for applying a DC voltage between the thin plate and the partition. Gate valve for thin film forming equipment. 2. The gate valve according to claim 1, wherein the thin plate has a surface of at least Rmax 0.1 μm or less on a side facing an outer peripheral portion of the opening.