JPH088213A - Method and apparatus for sputtering - Google Patents

Abstract

PURPOSE:To provide a sputtering method and the device for this method, which are effective for the uniform formation of a film especially on large substrate by eliminating uneven thickness of the formed film, which has been a problem heretofore. CONSTITUTION:A substrate 5, which is the object of film formation, is moved with respect to a target 12 of vapor-deposition parent material in a discharging region with a fluctuating device 30. The vapor deposition on the surface of the substrate 5 is repeated. The thickness of the film is gradually increased, and the film is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sputtering method for forming a base film for forming a thin film transistor (TFT) or the like on a surface of a substrate and an apparatus for the sputtering method.

[0002]

2. Description of the Related Art Sputtering is well known as one of the methods for forming a base film of a transparent electrode for TFT on a surface of a transparent substrate such as glass. In this method, when discharging in a heated atmosphere in a vacuum state, atoms are evaporated and scattered from a target as a deposition base material of a metal or compound, and a coating film is created by vapor deposition on the surface of the substrate, or etching is performed. It is widely applied to the
In the sputtering apparatus by such a method, for example, the substrate to be film-formed is sent to the process chamber by the transfer device, and here the discharge regions are formed so as to intersect in the transfer direction by energization between the anode plate and the cathode plate. . A target of a vapor deposition base material is arranged in the discharge region, and the substrate is passed in front of the target at a slow and constant speed. A thin film is formed on the target irradiated with the electric discharge by evaporating and spattering sputtered particles by atoms from the surface and depositing it on the surface of the substrate passing in front.

FIGS. 10 to 12 show movement modes of a substrate 5 supported by a tray 6 and passing in front of a target 12 before film formation, during film formation, and after film formation. The substrate 5 advances at a constant speed in the discharge region indicated by the broken line arrow e in the figure, and during passing, film formation is sequentially performed from the front part to the rear part in the moving direction of the substrate 5.

[0004]

By the way, according to such a conventional sputtering method and its apparatus, as shown in FIG. 13, a thin portion 21 having an insufficient film thickness occurs in the formed film 20 after the formation, and the film is formed. It often happens that the thickness is not uniform. In particular, such an inconvenience is particularly likely to occur during the formation of a vapor deposition film (used as a transparent electrode) such as ITO (Indium Tin Oxide) formed as a base film of a transparent electrode for TFT. The non-uniformity of film formation is said to be caused by abnormal discharge that frequently occurs due to frequent instantaneous stoppage of discharge. When the amount of sputtered particles flying from the target 12 decreases due to the abnormal discharge, a thin portion 21 as shown in FIG. 13 is generated, which becomes more remarkable as the area of the substrate 5 increases and the size increases. An object of the present invention is to provide a sputtering method and an apparatus therefor, which are effective in uniform film formation on a large-sized substrate, focusing on the problem of nonuniformity of film formation which has been a problem in the past.

[0005]

In order to achieve this object, in the sputtering method according to the first and second aspects of the invention, the substrate to be film-formed is swung with respect to the target of the vapor deposition base material within the discharge region. Then, vapor deposition is repeatedly performed on the surface of the substrate, and the film thickness is sequentially increased to form a film. The oscillating motion of the substrate may be a reciprocating motion that advances and retracts in the transport direction or a simple vibration with a variable frequency. Further, the sputtering apparatus according to the invention of claims 3 to 5 is characterized in that it is provided with an oscillating device for oscillating the substrate with respect to the target, and the oscillating device is carried on a tray and is being conveyed. Can be configured to be detached from the carrier together with the tray and rocked in front of the target. Further, the rocking device and an arm mechanism part for carrying the substrate together with the tray, detaching it from the carrier, and returning it again. Detecting when the substrate has arrived at a predetermined position before passing the target, and a quick return mechanism that quickly swings the arm mechanism that carries the substrate together with the tray after moving away from the transport device A first detecting means; a second detecting means for detecting that the substrate is detached from the transfer device; a counting means for measuring the end of swinging of the substrate and outputting a time-up signal; and a first detecting means. Control signal to control the detection signal from the arm mechanism section to send an operation signal for releasing the substrate, control the detection signal from the second detection section to send the operation signal to the fast return mechanism section, and send the time signal from the counting section. Control means for controlling the up signal to send an operation signal for returning the substrate to the arm mechanism part.

[0006]

In the sputtering method according to the first and second aspects of the present invention, a reciprocating motion for moving the substrate to be film-formed, which has been carried in front of the target in the discharge region, in the carrying direction, or By oscillating with a single frequency-variable vibration, thin film formation on the surface of the substrate is repeated several times to successively increase the film thickness, thereby forming a uniform film without forming a thin portion. In the sputtering apparatus according to the third to fifth aspects of the present invention, the substrate is carried by the carrier device while being carried on the tray, and the rocking device rocks the substrate received together with the tray from the carrier device in front of the target. . If the rocking device is composed of an arm mechanism part, a rapid return mechanism part, first and second detecting means, counting means, control means, etc., when the substrate sent by the transfer device reaches the target pre-passage position, Is detected by the first detecting means. The detection signal is sent to the control means, and the arm mechanism portion is operated by the operation signal for releasing the substrate, which is output from the control means, and carries the substrate together with the tray to detach it from the transport device. The second detecting means detects that the substrate is detached from the transporting device, and based on this detection signal, an operating signal is sent from the controlling means to the quick return mechanism section, and the substrate is rocked together with the tray by the operation of the quick return mechanism section. Let The counting means outputs the end of swinging of the substrate with a time-up signal, and based on the time-up signal, the control means outputs an operation signal for returning the substrate to the arm mechanism section. The substrate on the tray returned to the transfer device
It is delivered as it is. In this way, the control method is adopted to detect the position of the substrate before it reaches the target, and then to swing the target such as swift reciprocating motion, so regardless of the occurrence of abnormal discharge. , A film having a uniform film thickness is formed on all substrates.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the sputtering method and its apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a plan sectional view of the sputtering apparatus of the embodiment. The main part of the device 1 is that the substrate 5 can swing with respect to the target 12.
A tray 6 carrying the substrate 5 and the substrate 5 via the tray 6
And a swing device 30 that swings the substrate 5 received together with the tray 6 from the transport device 7 in front of the target 12.

The rocking device 30 can be constructed as shown in FIG. However, the illustrated mechanism is only an example for achieving the present invention, and the present invention is not limited to this, and various configurations are conceivable. The device 30 uses the substrate 5 for the tray 6
The arm mechanism portion 31 that carries the whole and detaches it from the transfer device 7 and returns it, and the quick return mechanism portion 35 that swivels the substrate 5 on the tray 6 separated from the transfer device 7 by the arm mechanism portion 31 rapidly in the transfer direction. , First detection means 37 for detecting that the substrate 5 has reached the position before the target 12 passes.
(See FIG. 1: This is hereinafter referred to as a first sensor.) Second detection means 3 for detecting that the substrate 5 is detached from the transport device 7.
8 (see FIG. 2: hereinafter referred to as second sensor), substrate 5
A counting means (not shown) is provided for measuring the end of the swing of and outputting a time-up signal. Furthermore, the device 30
Has a control means (not shown) including a CPU such as a microcomputer, controls the detection signal from the first sensor 37, and sends an operation signal for detaching the substrate to the arm mechanism portion 31, (2) Control the detection signal from the sensor 38 to send an actuation signal to the quick return mechanism section 35, and control the time-up signal from the counting means to send an actuation signal for substrate return to the arm mechanism section 31. Is configured.

Here, referring again to FIG. 1, in the sputtering apparatus 1, the carrying apparatus 7 is carried out from the carry-in gate 13 to the carry-out gate 16.
It is provided at a distance up to, and a normal roller conveyor or the like can be used. A transparent substrate 5 made of, for example, glass, which is a film formation target, is transported by this transport device 7 to form a base film for forming a transparent electrode for TFT or the like on the surface thereof. Is a dedicated tray 6
And is sent to the load chamber 2 from the gate port 16a one after another at appropriate intervals.

The load chamber 2 has a vacuum pump 9 for decompressing the inside of the chamber to maintain a vacuum state, and a heater 8 for heating the substrate 5 sent by the transfer device 7 from behind. A duct 19a for introducing N ₂ gas into the room is also provided here.

In the process chamber 3 of the next chamber adjacent to the partition gate 14, two sets of a pair of electrodes consisting of an anode plate 10 and a cathode plate 11 sandwich the carrier device 7 from both sides, and two substrates are placed back to back. It is arranged so as to correspond to 5 and 5. That is, a discharge region indicated by an arrow e is formed orthogonal to the transport direction by energizing between the two electrodes, and can correspond to the two substrates 5 and 5. In addition, the discharge area e
A target 12, which is a deposition base material, is mounted on the front part of the cathode plate 11 so that the substrate 5 on the tray 6 passes just before the target 12. Also,
In the process chamber 3, a duct 19b for introducing Ar gas into the room is provided, and a heater 8 for heating the substrate 5 from the rear side is also arranged here over the entire length of the room.

Further, a swing device 30 which is a main part is installed in the process chamber 3. In FIG. 2, the arm mechanism portion 31 has rods 33, 33 that reciprocate hydraulically or pneumatically from the front and rear of the housing so as to project in a relative direction, and the holding plate 3 is provided at the tip of the rod 33.
2 are provided. That is, the front and rear holding plates 32, 3
The two 2 move relative to each other in the opening direction and the closing direction, and the two holding plates 32, 32 can hold the U-shaped tray 6 between them.

The arm mechanism portion 31 has, for example, 4
It is in the form of being suspended and supported by a quick return mechanism portion 35 via a vertical movement rod 34 of the book. The quick return mechanism portion 36 is carried by a guide shaft 36 extending upward along the transport device 7,
It is possible to swing by reciprocating motion in the transport direction. The arm mechanism 31 can be moved up and down by the four rods 34 with respect to the quick return mechanism 36. The vertical movement of the arm mechanism portion 31 means the detachment and the return of the substrate 5 from the transfer device 7 according to the present invention, and this is performed for each tray 6, so that it is separated from the transfer device 7 to some extent above. The second sensor 38 detects the open position. FIG.
As shown in FIG. 3, the substrate 5 on the tray 6 transferred by the transfer device 7 is the target 1 in the discharge area.
At the stage where you have reached the position before passing 2
The sensor 37 detects it. Further, the fast-return mechanism section 36 has a built-in counting means (not shown), and the substrate 5 reciprocates in a stroke equivalent to the distance passing in front of the target 12 to end the swinging operation in a number of times. It measures time and outputs a time-up signal.

Further, the rocking device 30 is provided with a control means (not shown) having a CPU such as a microcomputer, and controls the operation of each of the above parts. That is, the detection signal from the first sensor 37 is controlled to send an operation signal for detaching the substrate to the arm mechanism section 31, and the detection signal from the second sensor 38 is controlled to send an operation signal to the quick return mechanism section 35. It is possible to perform a series of controls in which the time-out signal from the counting means is controlled and the operation signal for returning the substrate is sent to the arm mechanism section 31 while being sent.

Next, in the sputtering apparatus of the embodiment having the above structure, the sputtering method for forming a film on the surface of the substrate 5 and its operation will be described. A large number of substrates 5 can be activated by the device
Are carried by the respective trays 6 and carried in by the carrying device 7. Pretreatment such as evacuation and heating is performed in the load chamber 2 and the pretreatment is sent to the process chamber 3.
In the process chamber 3, the discharge regions e are formed so as to intersect with each other in the transport direction by energization between the anode plate 10 and the cathode plate 11. In the room, vacuuming is still performed and the substrate 5 is heated by the heater 8 from behind. A
By encapsulating the r gas, the vaporized atoms from the target 12 are caused to react with each other, and vapor deposition is performed on the surface of the substrate 5.

The substrate 5 has the target 1 in the discharge region e.
The first sensor 37 detects this when reaching a predetermined position before approaching 2. This detection signal is sent to the control means of the rocking device 30, and the controlled actuation signal is sent to the arm mechanism section 31 for the purpose of removing the substrate. The arm mechanism section 31 descends, and the front and rear holding plates 32, 32 hold the left and right 2
The substrates 5 and 5 are held together with the tray 6. When the substrate 5 is detached upward from the transfer device 7 due to the rise of the arm mechanism portion 31, the second sensor 38 detects it at a predetermined height. By the control based on this detection signal, the quick return mechanism unit 35
An activation signal is sent to.

3 to 7 show a film forming operation in the case where the substrate 5 is rapidly reciprocated in front of the target 12 as swinging by the quick return mechanism section 35. In these figures, the swinging device 30 moves the substrate 5 forward and backward with a stroke of passing the front of the target 12 in the discharge region e from the front end to the rear end, and the reciprocating movement thereof is shown. Rapid return mechanism section 3
It is also possible to change the substrate 5 by means of 5 to reciprocating motion and to make a simple vibration that can be modulated. That is, by the discharge, the sputtered particles due to the atoms are scattered from the target 12 and adhere to the entire surface of the substrate 5 which is passing therethrough to form a thin film. The surface of the substrate 5 is formed by increasing the film thickness by repeating the forward and backward paths.

If an abnormal discharge is generated in the discharge area e during film formation and the amount of sputtered particles flying from the target 12 is temporarily reduced, the film formation in the middle is as shown in FIG. That is, the thin film portion 41 locally occurs in the film formation 40 on the substrate 5. However, even if such an inconvenience occurs, since the substrate 5 reciprocates, the thin film portion 42 can be finally relaxed to form the film 40 as shown in FIG.

The substrate 5 on which the film has been formed is sent to the unload chamber 4, where the room pressure is returned to atmospheric pressure, and the substrate 5 is removed.
Is cooled by a cooling device (not shown). After that, the transfer conveyor 7 carries out the completed substrate 5 from the carry-out gate 16 to the outside of the apparatus.

[0020]

As described above, according to the sputtering method and the apparatus therefor according to the present invention, the substrate is oscillated with respect to the target by reciprocating motion or simple vibration, and the film is formed in the film thickness direction by reciprocating motion. Since it is a method in which the thickness gradually increases, even if a thin portion locally occurs in the film due to abnormal discharge, it is effective to alleviate this and obtain uniformity over the entire surface of the film.

[Brief description of drawings]

FIG. 1 is a plan sectional view of an embodiment of a sputtering apparatus according to the present invention.

FIG. 2 is a perspective view of an oscillating device in the sputtering apparatus of the embodiment.

FIG. 3 is a plan view of a film forming operation using a reciprocating sputtering method as an example of rocking.

FIG. 4 is a plan view of the film forming operation.

FIG. 5 is a plan view of the film forming operation.

FIG. 6 is a plan view of the film forming operation.

FIG. 7 is a plan view of the film forming operation.

FIG. 8 is a side sectional view of the substrate showing the form of a thin portion due to the occurrence of abnormal discharge.

FIG. 9 is a side cross-sectional view of a mode in which the adverse effect of abnormal discharge is eliminated by the sputtering method according to the present invention to obtain a uniform film.

FIG. 10 is a plan view of a film forming operation by a conventional apparatus.

FIG. 11 is a plan view of the film forming operation by the conventional apparatus.

FIG. 12 is a plan view of the film forming operation by the conventional device.

FIG. 13 is a side cross-sectional view of a substrate in a non-uniform manner in which a thin portion is generated in the film formation due to abnormal discharge in the conventional apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sputtering device 5 Substrate 6 Tray 7 Transfer device 12 Target 30 Swinging device 31 Arm mechanism part 32 Holding plate 35 Fast return mechanism part 37 1st sensor (1st detection means) 38 2nd sensor (2nd detection means)

Claims (5)

[Claims] 1. A substrate to be film-formed is oscillated with respect to a target of a vapor deposition base material in a discharge region, vapor deposition is repeatedly performed on the surface of the substrate, and film formation is performed while the film thickness is sequentially increased. Characteristic sputtering method. 2. The sputtering method according to claim 1, wherein the oscillating motion of the substrate is a reciprocating motion that advances and retreats in the transport direction or a simple vibration with a variable frequency. 3. A sputtering apparatus comprising a swinging device for swinging the substrate with respect to a target deposited on the surface of the substrate by irradiation by discharge. 4. The sputtering apparatus according to claim 3, wherein the swinging device causes the substrate, which is carried on the tray and is being transported, to be separated from the transporting device together with the tray and swings in front of the target. 5. A target of an oscillating device is an arm mechanism part for supporting a substrate together with a tray and detaching it from a transport device and returning it again, and an arm mechanism part for detaching the substrate and carrying a substrate together with the tray. Fast-return mechanism that swivels quickly in front of the substrate, first detection means for detecting that the substrate has reached a predetermined position before passing the target, and second detection for detecting that the substrate has separated from the transfer device. Means, counting means for measuring the end of rocking of the substrate and outputting a time-up signal, and controlling the detection signal from the first detecting means to send an operation signal for releasing the substrate to the arm mechanism part. Control means for controlling the detection signal from the detecting means to send an actuation signal to the fast return mechanism section, and for controlling a time-up signal from the counting means to send an actuation signal for substrate return to the arm mechanism section; Equipped The sputtering apparatus according to claim 4.