JP4378790B2 - Sputtering method and sputtering apparatus for glass substrate - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a sputtering method and apparatus for forming a thin film on a large glass substrate used for a plasma display panel or the like, and more particularly to sputtering performed with a glass substrate held vertically.
[0002]
Since a glass substrate used for a plasma display panel or the like has a large area, processing in a vertical state is more efficient than processing in a horizontal state requiring a large floor area. Therefore, it is required to perform the treatment in a vertical state stably and reliably also in the sputtering method.
[0003]
[Prior art]
A glass substrate in a plasma display panel (hereinafter referred to as PDP) is provided with a plurality of discharge electrodes constituting a display cell, and in forming these electrodes, a process of forming a metal thin film on substantially the entire surface of the glass substrate. There is.
[0004]
The formation of the metal thin film employs a sputtering technique that is common as a method for depositing a metal film on glass. Hereinafter, conventional thin film formation by sputtering will be described with reference to FIG. 8A and 8B are diagrams for explaining the conventional technique. FIG. 8A is a front view of a substrate holder used for holding a glass substrate at the time of sputtering, and FIG. 8B is A in FIG. 8A. -A 'sectional side view, FIG.8 (c) is BB' upper sectional drawing of Fig.8 (a).
[0005]
As described in the previous section, in order to increase the processing efficiency, the glass substrate is sputtered while being held vertically, and FIG. 8 shows this state.
[0006]
As shown in FIG. 8, the glass substrate 61 is held between the front holder 62 and the rear holder 63 on the base body 65, and the surface exposed from the opening 62 a of the front holder 62 is subjected to sputtering. In FIG. 8A, the central region is the surface of the glass substrate 61 that can be seen through the opening 62a, and this region is sputtered to form a chromium or copper metal thin film.
[0007]
In addition to the opening 62 a, the front holder 62 includes a substrate support portion 64 that receives the lower surface of the glass substrate 61, and a guide portion 68 that prevents displacement of the glass substrate 61. As can be seen from FIG. 8A, a plurality of these substrate support portions 64 and guide portions 68 are provided so as to be scattered in the peripheral portion of the glass substrate 61, and as shown in FIGS. Projecting inward of the holder 62.
[0008]
On the other hand, the rear holder 63 is arranged in parallel with a position spaced apart from the front holder 62 by a predetermined distance, and has a holding spring 67 that presses the glass substrate 61 toward the front holder 62.
[0009]
Since the glass substrate 61 is in a vertical state, it is unstable and falls down only by being supported by the substrate support portion 64, so it is necessary to press the glass substrate 61 with a pressing spring 67.
[0010]
The front holder 62 is configured to be rotated forward by the operation of the rotation shaft 66. The glass substrate 61 is placed in an open state, and then the front holder 62 is closed to hold the glass substrate 61 to the front by a holding spring 67. It is pressed to the holder 62 side to obtain the holding state shown in FIG.
[0011]
In such a state, the metal thin film is formed on the surface of the glass substrate 61, that is, the surface exposed from the opening 62 a of the front holder 62 by being transferred into a sputtering apparatus (not shown) and performing a sputtering process.
[0012]
Although not shown, the transfer is performed by a conveyance path that moves while supporting the lower surface of the base body 65.
[0013]
[Problems to be solved by the invention]
Sputtering is a process in which a raw material is scattered by an ion bombardment to a raw material target in a low-pressure processing chamber, and this is attached to an object to be processed, but it is originally heated to stabilize the film quality of the thin film to be attached. In addition, the heat generated at the time of ion bombardment causes the processing chamber to reach a high temperature of several hundred degrees Celsius.
[0014]
Therefore, the glass substrate in the processing chamber becomes high temperature, and the glass substrate having a large area is warped.
[0015]
FIG. 9 is a diagram for explaining a problem of the conventional technique, and shows a state in which the glass substrate is warped.
[0016]
9A is a side cross-sectional view showing a normal state of the glass substrate 41 before the sputtering process, FIG. 9B is a side cross-sectional view showing a state in which warpage occurs during the sputtering process, and FIG. 9C. These are sectional side views of Drawing 9 (a) (b). FIG. 9C shows a normal state with a solid line and a warped state with a broken line. The reference numerals are the same as those in FIG.
[0017]
The glass substrate 61 has a large area of, for example, 50 inches, but has a thin thickness of about 3 mm. Therefore, as shown in FIG. 9A, the temperature of the glass substrate 61 held by being pressed against the front holder 62 by the substrate support portion 64 of the front holder 62 and the holding spring 67 of the rear holder 63 increases. As a result, warping occurs and the state shown in FIG.
[0018]
In the vicinity of the center of the glass substrate 61, the glass substrate 61 moves from the front holder 62 side to the rear holder 63 side as indicated by an arrow. FIG. 9C is a side sectional view of the vicinity of the center, and the glass substrate 61 has moved from the position indicated by the solid line to the position indicated by the broken line.
[0019]
The glass substrate 61 is supported by adding substantially the entire weight to the substrate support portion 64. When the glass substrate 61 moves on the substrate support portion 64 due to the above-described warpage, an extremely large load is applied to the portion due to frictional force. . In a large area and thin glass substrate 61, if a large load is applied partially, substrate cracking may occur starting from that portion.
[0020]
An object of the present invention is to provide a glass substrate sputtering method and apparatus capable of solving the above-described problems and stably and reliably performing the formation of a metal thin film in a vertical state without causing substrate cracking. Yes.
[0021]
[Means for Solving the Problems]
The present invention for solving the above problems is a sputtering method in which a thin film is formed on the surface of a glass substrate while the glass substrate is held substantially vertically, and a roller that rotates in a direction orthogonal to the surface of the glass substrate. The substrate supporting part is provided, and a process of forming a thin film on the surface of the glass substrate is performed in a state where the glass substrate is supported on the roller of the substrate supporting part.
[0022]
According to the present invention, when the glass substrate is warped due to a high temperature during sputtering, the glass substrate is supported by a roller that rotates in the moving direction due to the warpage, so the frictional force during movement is reduced, The load applied to the glass substrate can be extremely reduced. Therefore, it is possible to suppress the substrate cracking when warping occurs.
[0023]
Further, the present invention is a sputtering method in which a thin film is formed on the surface of the glass substrate while the glass substrate is held substantially vertically, and is suspended by supporting the upper portion of the glass substrate. A process of forming a thin film on the surface of the glass substrate is performed.
[0024]
According to the present invention, when the glass substrate is warped due to a high temperature during sputtering, the frictional force due to the warp can be eliminated from the suspended state, and it is possible to suppress substrate cracking. Become.
[0025]
Further, the present invention provides a sputtering method in which a thin film is formed on the surface of the glass substrate while the glass substrate is held substantially vertically, and the glass substrate is supported while being inclined toward the surface to be processed. Using a raw material target that is inclined and arranged parallel to the glass substrate at a position facing the glass substrate, a process of forming a thin film on the surface of the glass substrate is performed.
[0026]
According to the present invention, since the weight of the glass substrate can be dispersed, the frictional force when the glass substrate is warped due to a high temperature during sputtering is also dispersed, and the substrate cracking can be suppressed.
[0027]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0028]
1-4 is a figure for demonstrating the 1st Embodiment of this invention, FIG. 1 is sectional drawing and front view of a substrate holder, FIG. 2 is the elements on larger scale of a front holder, FIG. FIG. 4 is a plan view of the processing apparatus (sputtering apparatus).
[0029]
As shown in FIG. 1A, the glass substrate 1 is subjected to sputtering while being held between a front holder 2 and a rear holder 3 on a base body 9.
[0030]
The front holder 2 has an opening 2 a for exposing the surface of the glass substrate 1, a substrate support portion 4 that protrudes toward the back holder 3 and supports the glass substrate 1, and a guide portion 8 that prevents displacement. ing. The substrate support part 4 is provided with a plurality of rollers 5 whose rotation direction is matched with the thickness direction of the substrate at a portion that contacts the lower surface of the glass substrate 1.
[0031]
The back holder 3 has a holding spring 7 that presses the glass substrate 1 against the front holder 2 side. The holding spring 7 is set to a low pressure in order to suppress damage to the glass substrate 1.
[0032]
FIG. 1B is a front view of FIG. 1A, but the back holder 3 and the holding spring 7 are omitted when viewed from the back holder 3 side.
[0033]
As shown in FIG. 1B, the substrate support portions 4 are provided at three locations on the front holder 2, and each supports the glass substrate 1 with a roller 5. A plurality of guide portions 8 are provided at positions corresponding to the upper surface and the side surface of the glass substrate 1.
[0034]
The rotating shaft 6 provided in the base body 9 is connected to the front holder 2 and is configured to rotate the front holder 2 by rotating. As will be described later, the substrate holder 10 of the present embodiment has a front holder 2 on both sides of the back holder 3 as a center, and can hold two glass substrates 1 back to back. .
[0035]
FIG. 2 is a partially enlarged view clearly showing the structure of the substrate support portion. As shown in FIG. 2, the substrate support portion 4 of the front holder 2 includes a plurality of rollers 5, and is configured to support the glass substrate 1 on the rollers 5.
[0036]
The roller 5 is provided so as to be rotatable in a direction orthogonal to the surface of the glass substrate 1, that is, in the thickness direction of the substrate, and the glass substrate 1 moves on the substrate support portion 4 due to a warp accompanying a temperature rise. The roller 5 rotates in accordance with this movement. That is, when the glass substrate 1 tries to move as shown by the arrow in FIG. 2, the roller 5 rotates to move the glass substrate 1, so that the frictional force at that time becomes extremely small.
[0037]
FIG. 3 is a perspective view showing the entire substrate holder including the peripheral portion such as the conveyance path, and the operation thereof will be specifically described below.
[0038]
As described with reference to FIG. 1, the substrate holder 10 holds the glass substrate 1 in a vertical state between the front holder 2 and the rear holder 3, and as shown in FIG. Front holders 2 are arranged on both sides. With such a configuration, two glass substrates 1 can be held back to back and sputtering can be performed simultaneously from both sides.
[0039]
The substrate holder 10 holding the two glass substrates 1 is moved into the processing apparatus 11 through the loading / unloading exit 12 by moving on the conveyance path 13 connecting the inside and outside of the processing apparatus 11, and predetermined sputtering is performed. Applied.
[0040]
FIG. 3 shows the substrate holder 10 in a state where the front holder 2 is opened (front side) and a state where the front holder 2 is closed (back side). Like the substrate holder 10 in the foreground, the front holder 2 can be opened by rotating the rotary shaft 6, and the glass substrate 1 before processing which is transported by another transport path 15 in this state has a suction pad. It is mounted on the inner surface of the front holder 2 by an arm (not shown). (The movement of the glass substrate 1 is indicated by a dashed line)
At this time, the glass substrate 1 is mounted so that it may be located in the area | region enclosed by the board | substrate support part 4 which has the roller 5, and the guide part 8 (refer FIG. 1) which is abbreviate | omitted in FIG.
[0041]
Thereafter, by rotating the rotating shaft 6 in the reverse direction, the front holder 2 is returned to the original state, and the glass substrate 1 is held. That is, when the front holder 2 is closed with the glass substrate 1 mounted, the glass substrate 1 is supported on the substrate support portion 4 by gravity and is pressed to the front holder 2 side by the pressing spring 7 of the rear holder 3. By being attached, it is in a state of being held vertically.
[0042]
The front holder 2 provided opposite to the opposite side of the rear holder 2 is already closed and holds the glass substrate 1.
[0043]
The back substrate holder 10 is such that both front holders 2 are closed and a pair of glass substrates 1 are held back to back, and then moves on the conveyance path 13 and enters the processing apparatus 11 via the carry-in / out port 12. Will be sent to.
[0044]
In FIG. 3, in order to clarify the structure of the holding spring 7 and the roller 5, these portions are shown larger than the actual size.
[0045]
Next, the operation of the substrate holder in the processing apparatus 11 will be described with reference to the processing apparatus plan view of FIG.
[0046]
As shown in FIG. 4, a loop-shaped conveyance path is disposed in the processing apparatus 11, and a sputtering process is performed on a part thereof.
[0047]
The substrate holder 10 holding the glass substrate 1 enters the processing apparatus 11 from the carry-in / out port 12 and is first sent to the preheating chamber 16. The inside of the preheating chamber 16 is in a vacuum atmosphere, and by setting the glass substrate 1 to about 100 to 200 ° C., moisture and the like attached to the surface is evaporated to make the surface clean. By performing such preheating and cleaning the surface of the glass substrate 1, the film quality of the thin film to be formed can be improved.
[0048]
Thereafter, the process proceeds to the processing chamber 17 where sputtering is performed. The inside of the processing chamber 17 is in a low pressure state of about 0.5 Pa (Pascal), and targets 19 are arranged on both sides of the conveyance path. In such a processing chamber 17, a chromium or copper thin film is simultaneously formed on the pair of glass substrates 1 held back to back on the substrate holder 10.
[0049]
In the processing chamber 17, the temperature of the glass substrate 1 rises to about 350 to 400 ° C., which causes warping.
[0050]
At this time, in the case of the present embodiment, since the glass substrate 1 moves on the roller 5 (see FIG. 2) provided in the substrate support portion 4, the frictional force is small and the possibility of causing the substrate cracking is suppressed as much as possible. it can.
[0051]
The glass substrate 1 on which the predetermined thin film is formed is sent to the cooling chamber 18 while being held by the substrate holder 10 as it is. Here, the temperature of the glass substrate 1 is gradually lowered to prevent substrate cracking due to a rapid temperature drop.
[0052]
The substrate holder 10 that has passed through the cooling chamber 18 is unloaded from the loading / unloading port 12 to the outside of the processing apparatus 11. And the processed glass substrate 1 is taken out in the state which opened the front holder 2 by rotation of the rotating shaft 6. FIG. The substrate holder 10 from which the glass substrate 1 has been taken out holds the unprocessed glass substrate 1 again and is sent into the processing apparatus 11 to repeatedly perform sputtering.
[0053]
The glass substrate 1 is taken out and mounted by a robot arm as described above.
[0054]
A plurality of substrate holders 10 are always present in the processing apparatus 11, and loading and unloading are repeated at a predetermined timing.
[0055]
5A and 5B are views for explaining a second embodiment of the present invention, in which FIG. 5A is a side sectional view of the substrate holder, and FIG. 5B is a partially enlarged perspective view of the front holder.
[0056]
In the first embodiment, the frictional force at the time of warpage due to temperature change is reduced by the roller support. However, in the second embodiment, the warp is generated by holding the glass substrate by holding it. It eliminates the frictional force of time. That is, the glass substrate is not supported from the lower side but is held in a suspended state.
[0057]
As shown in FIG. 5A, the substrate holder 30 of the present embodiment includes a top plate 28 on the front holder 22 having an opening 22a, and the top plate 28 is provided with a holding clip 27 via an elastic member 27a. It has been.
[0058]
As shown in FIG. 5 (b), the clip clips 27 are provided on the top plate 28 at predetermined intervals and hold the glass substrate 21. This sandwiching clip 27 is made of a heat-resistant resin material at least at a portion that comes into contact with the glass substrate 21, so that thermal stress is not applied to the glass substrate 21, and the clip clip 27 is held by the action of a stretchable elastic material 27 a. It can move up and down and left and right so as to follow the warp of the glass substrate 21.
[0059]
Therefore, when the glass substrate 21 is warped due to a temperature change, no frictional force is generated and the substrate is not cracked.
[0060]
Although not shown, a vespel material is provided at a portion of the sandwiching clip 27 that contacts the glass substrate 21.
[0061]
Moreover, since it hold | maintains in the state which clamped and hung the upper part of the glass substrate 21, the holding | suppressing spring with which 1st Embodiment is equipped becomes unnecessary. When the glass substrate is warped, the pressure of the holding spring also applies a slight stress to the glass substrate, and this stress can be eliminated.
[0062]
Although omitted in FIG. 5, the front holders 22 are provided on both sides of the rear holder 23 on the base body 29 as in the first embodiment described with reference to FIG. 3, and each front holder 22 rotates. The shaft 26 is rotated by the rotation of the shaft 26.
[0063]
Further, the processing apparatus is the same as that of the first embodiment shown in FIG. 4, and the processing such as transport of the substrate holder 30 is also performed by the same method.
[0064]
6A and 6B are views for explaining a third embodiment of the present invention, in which FIG. 6A is a side sectional view of the substrate holder, and FIG. 6B is a partially enlarged perspective view of the front holder.
[0065]
The present embodiment is a modification of the second embodiment, and holds the glass substrate 31 so as to hang using the support holes provided in the glass substrate 31 in advance.
[0066]
That is, as shown in FIG. 6A, the substrate holder 40 includes a top plate 38 on the upper portion of the front holder 32 having the opening 32a, and the surface of the substrate holder 40 is formed of a heat-resistant resin via an elastic member 37a. A support hook 37 made of a material is provided.
[0067]
As shown in FIG. 6 (b), the support hooks 37 are provided on the top plate 28 at predetermined intervals, and are fitted into the support holes 31 a opened in the glass substrate 31, so that the glass substrate 31 is held in a suspended state.
[0068]
Since the support hook 37 is provided on the top plate 38 via the extension spring 37a, the support hook 37 can be moved up, down, left and right by the action of the extension spring 37a so as to follow the warp of the glass substrate 31 being held. it can.
[0069]
Therefore, as in the second embodiment, when the glass substrate 31 is warped due to a temperature change, no frictional force is generated and the substrate is not cracked. Although not shown in the figure, a portion of the support hook 37 that comes into contact with the glass substrate 31 is provided with a bespel material.
[0070]
Furthermore, as in the second embodiment, it is not necessary to provide a pressing spring on the back side of the glass substrate 31, and stress can be alleviated.
[0071]
Although omitted in FIG. 6, the front holders 32 are provided on both sides of the rear holder 33 on the base body 39 as in the first embodiment described with reference to FIG. 3, and each front holder 32 rotates. The shaft is rotated by the rotation of the shaft.
[0072]
Further, the processing apparatus is the same as that of the first embodiment shown in FIG. 4, and the processing such as transport of the substrate holder 40 is also performed by the same method.
[0073]
FIG. 7 is a view for explaining the fourth embodiment of the present invention, and is a side sectional view showing a part of the substrate holder and the processing apparatus.
[0074]
In the present embodiment, the glass substrate is held in an inclined state in order to reduce the frictional force when the glass substrate warps due to a temperature change.
[0075]
As shown in FIG. 7, in the substrate holder 50 of the present embodiment, both the front holder 42 and the rear holder 43 are inclined while the glass substrate 41 is held.
[0076]
That is, when the lower surface of the glass substrate is supported in a vertical state, the entire weight of the glass substrate is added to the substrate support portion. However, by making the glass substrate 41 in an inclined state as in this embodiment, the weight of the glass substrate 41 is reduced. The substrate support portion 44 that supports the lower surface and the contact surface between the front substrate 42 and the glass substrate 41 are dispersed.
[0077]
Therefore, the frictional force at the time of occurrence of warping due to temperature change is not concentrated on a part of the glass substrate 41 and is dispersed, so that substrate cracking can be suppressed. A bespel material is provided on the surface of the front holder 42 that contacts the glass substrate 41.
[0078]
In addition, since the glass substrate 41 is supported in an inclined state, a stable state is obtained, and a pressing spring is unnecessary as in the second and third embodiments, and stress due to the pressing spring can be eliminated.
[0079]
In the case of this embodiment, since the glass substrate 41 is inclined, in order to form a thin film evenly on the surface thereof, the processing apparatus 51 is also configured to incline each component as shown in FIG.
[0080]
The processing apparatus 51 has a target 47 that is inclined so as to be parallel to the glass substrate 41 at a position facing the glass substrate 41 held by the substrate holder 50. A target 47 such as chrome or copper is provided on a metal back plate 48, and a magnet accommodating portion 49 for generating a magnetic field is provided on the back surface thereof.
[0081]
The inside of the processing apparatus 51 with the substrate holder 50 is a low-pressure atmosphere containing an ion gas, and the ion gas collides with the target 47 when a magnetic field is applied, and the raw material scattered from the target 47 is exposed from the opening 42a. By attaching to the surface of the substrate 41, a thin film of chromium or copper is formed.
[0082]
In the first to third embodiments, the detailed description is omitted, but the configuration of the target peripheral portion and the thin film formation principle are the same as those described above with reference to FIG. .
[0083]
Thus, since the target 47 is inclined according to the glass substrate 41, it is possible to form a thin film evenly on the surface of the glass substrate 41. According to the present embodiment, the stress applied to the glass substrate 41 when warping occurs can be reduced with a simple configuration, and a uniform thin film can be formed without causing substrate cracking.
[0084]
The smaller the inclination angle of the substrate holder 50 is, the smaller the weight applied to the substrate support portion that rubs when warping occurs, and the occurrence of substrate cracks starting from that portion decreases. Since the floor area becomes large and the processing efficiency is lowered, it is desirable to set the angle close to the vertical and secure the stability, for example, 70 to 85 degrees.
[0085]
【The invention's effect】
According to the sputtering method and apparatus for a glass substrate of the present invention, when the glass substrate is warped by heat treatment, the glass substrate is supported by a roller that rotates in the moving direction due to the warpage, so that the frictional force at the time of movement is The load can be reduced. Therefore, it is possible to suppress substrate cracking.
[Brief description of the drawings]
FIG. 1 is a sectional view and a front view of a substrate holder according to a first embodiment of the present invention.
FIG. 2 is a partially enlarged perspective view of a front holder according to the first embodiment of the present invention.
FIG. 3 is an overall perspective view of a substrate holder according to the first embodiment of the present invention.
FIG. 4 is a plan view of a processing apparatus according to the first embodiment of the present invention.
FIG. 5 is a diagram for explaining a second embodiment of the present invention.
FIG. 6 is a diagram for explaining a third embodiment of the present invention.
FIG. 7 is a diagram for explaining a fourth embodiment of the present invention.
FIG. 8 is a diagram for explaining a conventional technique.
FIG. 9 is a diagram for explaining a problem of a conventional technique.
[Explanation of symbols]
1, 21, 31, 41 Glass substrate 2, 22, 32, 42 Front holder 3, 23, 33, 43 Rear holder 4 Substrate support portion 5 Rollers 6, 26, 36, 46 Rotating shaft 7 Pressing spring 8 Guide portion 9, 29, 39, 45 Base body 10, 30, 40, 50 Substrate holder 27 Holding clip 37 Support hook

Claims (3)

In a sputtering method for forming a thin film on the surface of the glass substrate while maintaining the glass substrate substantially vertically,
A thin film is formed on the surface of the glass substrate with a substrate supporting portion having a roller that rotates in a direction orthogonal to the surface of the glass substrate, with the glass substrate supported on the roller of the substrate supporting portion. A glass substrate sputtering method characterized by performing a treatment. In a sputtering method for forming a thin film on the surface of the glass substrate while maintaining the glass substrate substantially vertically,
It is suspended by supporting the upper part of the glass substrate, and in this state, a process for forming a thin film on the surface of the glass substrate is performed, and means for supporting the upper part of the glass substrate is fixed via an elastic material. The glass substrate sputtering method , wherein the glass substrate moves following the shape change of the glass substrate. In a sputtering apparatus that forms a thin film on the surface of a glass substrate while maintaining the glass substrate substantially vertically,
It has a substrate support portion having a roller that rotates in one direction, and supports the glass substrate on the roller of the substrate support portion substantially vertically with the rotation direction of the roller and the thickness direction of the substrate being matched. Sputtering device characterized.

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