JP4785362B2 - Substrate bonding apparatus and substrate bonding method - Google Patents

Description

The present invention relates to a substrate bonding apparatus and a substrate bonding method suitable for use in manufacturing liquid crystal display panels used for OA devices such as personal computers and monitor displays, and portable information communication devices.

  A configuration of a conventional substrate bonding apparatus will be described with reference to FIG. The substrate bonding apparatus includes a vacuum chamber 2 for storing two substrates 1a and 1b and bonding them in a reduced pressure atmosphere, and a vacuum pump 4 connected to the vacuum chamber 2 via a pipe 3. ing. The vacuum pump 4 includes a dry pump (DP), a mechanical booster pump (MB), and a turbo molecular pump (TB).

  The pipe 3 is provided with an open / close valve 5, and the open / close valve 5 is configured to be controlled by the controller 6 together with the vacuum chamber 2 and the vacuum pump 4.

When a liquid crystal display panel is manufactured using a substrate bonding apparatus, a substrate 1a onto which liquid crystal has been dropped and the other substrate 1b to be bonded to the substrate 1 are carried into the vacuum chamber 2 so as to face each other, and then the opening / closing valve 5 The vacuum chamber 4 is evacuated by the vacuum pump 4, the two substrates 1a and 1b are aligned and bonded, and then the vacuum chamber 2 is released to atmospheric pressure, and the two bonded sheets A bonding method of carrying out the substrates 1a and 1b from the vacuum chamber 2 is employed (see, for example, Patent Document 1).
JP 2000-66163 (right column on page 7)

  In the conventional substrate bonding apparatus, the vacuum chamber is evacuated using a vacuum pump connected to the vacuum chamber. FIG. 7 shows an exhaust speed characteristic curve when the vacuum chamber is evacuated with a vacuum pump.

The vacuum pump starts evacuation from the state where the inside of the vacuum chamber is at the atmospheric pressure Po (for example, 10 ⁵ [Pa]), but the initial exhaust speed Vo under the atmospheric pressure Po is set at the pressure Pm as the degree of vacuum increases. The characteristic is that it is smaller than the peak exhaust velocity Vm. Therefore, it takes a long time to evacuate the vacuum chamber occupying a certain space volume.

Therefore, the present invention has an object to provide a substrate bonding apparatus and a substrate bonding method that improve the rising characteristics at the initial exhaust speed at the time of evacuation in a vacuum chamber, and can perform evacuation in a short time. To do.

  The present invention was made by paying attention to the fact that evacuation by a vacuum tank forms a good initial evacuation speed. The vacuum apparatus of the present invention is connected to a vacuum chamber for storing articles and to this vacuum chamber. A vacuum tank that can be evacuated; a vacuum pump connected to the vacuum chamber; and an open / close valve that can selectively communicate between the vacuum chamber and the vacuum tank and between the vacuum chamber and the vacuum pump. It is characterized by comprising.

The present invention provides a substrate laminating apparatus for laminating two substrates held vertically opposite to each other in a decompressed vacuum chamber.
Coupled to said vacuum chamber, a vacuum tank vacuum evacuable,
A vacuum pump connected to said vacuum chamber,
Selectively and communicatively opening and closing valve between said vacuum pump and between the vacuum chamber and said vacuum tank and the vacuum chamber,
After starting the evacuation of said vacuum chamber by said vacuum tank, said even before the evacuation is completed by vacuum tank, vacuum within the vacuum chamber by evacuation by the vacuum tank to a predetermined first pressure and control means for switching control of the opening and closing valve so as to initiate the evacuation of the vacuum chamber by the vacuum pump at the time of the,
It is characterized by comprising.

Further, the substrate bonding method of the present invention includes a step of carrying two substrates in a vacuum chamber and opposingly arranging them vertically.
After this step, a first evacuation step of evacuating the vacuum chamber by a vacuum tank,
After the first evacuation step is started and before the first evacuation step is completed, when the vacuum chamber is depressurized to a predetermined first pressure by evacuation by the vacuum tank. a second vacuum step of evacuating the vacuum chamber by the vacuum pump,
After the first evacuation step and the second vacuum step, a step of bonding the two substrates in the vacuum chamber,
After this step, characterized by comprising the step of unloading the two sheets of substrates bonded by returning the vacuum chamber to atmospheric pressure from the vacuum chamber.

In the substrate bonding apparatus of the present invention , since the vacuum pump and the vacuum tank are connected to the vacuum chamber, the vacuum chamber can be evacuated using the vacuum tank prior to the vacuum pump, and the rising characteristics of the evacuation are improved. The evacuation time can be shortened.

  Further, according to the substrate bonding method of the present invention, prior to the second evacuation step in which the vacuum chamber is evacuated by the vacuum pump, in the first evacuation step, the vacuum chamber is evacuated by the vacuum tank. Therefore, the rising characteristics of evacuation are improved, and the evacuation time can be shortened.

  Hereinafter, an embodiment of a substrate bonding apparatus and a substrate bonding method of the present invention will be described with reference to FIGS. 1 and 4, the same reference numerals are given to the same components as those of the conventional configuration shown in FIG. 6, and detailed description thereof is omitted.

  That is, FIG. 1 shows the configuration of the first embodiment of the substrate bonding apparatus according to the present invention, and includes an upper table (not shown) that holds one substrate 1a out of the two substrates 1a and 1b to be carried in. A vacuum chamber 2 that houses a bonding mechanism formed by facing a lower table (not shown) that holds the other substrate 1b, a pressure measuring device 2a installed in the vacuum chamber 2, and the vacuum The vacuum pump 4 is connected to the chamber 2 via a pipe 31 and the vacuum tank 7 is also connected to the vacuum chamber 2 via a pipe 32. The vacuum pump 4 and the vacuum tank 7 are connected via a pipe 33. It is connected.

  The pipe 31 is provided with an open / close valve 51, the pipe 32 is provided with an open / close valve 52, and the pipe 33 is provided with an open / close valve 53.

  Each open / close valve 51, 52, 53 is configured to be controlled by a controller 6 together with the vacuum chamber 2, the pressure measuring device 2 a, and the vacuum pump 4.

  Here, in order to make the explanation easy to understand, each of the pipes 31 to 33 will be described as having the same diameter (cross-sectional area) as the pipe 3 of the prior art shown in FIG.

  Hereinafter, the operation and operation procedure of the substrate bonding apparatus according to the present embodiment are shown in the configuration diagram of FIG. 1, the flowchart shown in FIG. 2, and the exhaust speed of the vacuum chamber 2 by the vacuum pump 4 and the vacuum tank 7 shown in FIG. This will be described with reference to the characteristic curve.

  FIG. 3 is a graph showing a characteristic curve of the exhaust speed with respect to pressure, and the pressure change in the vacuum chamber 2 corresponds to the passage of time after the start of evacuation. The elapsed time point from the evacuation start time T0 will be described below with T1 and T2. In FIG. 3, the alternate long and short dash line shows the characteristic curve 3A of the exhaust speed by the vacuum tank 7, and the dotted line and the solid line connected thereto show the characteristic curve 3B of the exhaust speed by the vacuum pump 4 in the same manner as the characteristic curve shown in FIG. Is.

  First, in the substrate bonding apparatus having the above configuration, the controller 6 controls the drive of the vacuum chamber 2 so that the two substrates 1a and 1b sequentially carried into the vacuum chamber 2 are bonded together in a vacuum atmosphere. . Therefore, the controller 6 controls opening / closing of the opening / closing valves 51, 52, 53 at a timing synchronized with the bonding operation, and executes evacuation for the vacuum chamber 2. In the following description, it is assumed that the vacuum pump 4 is always operating.

  That is, as shown in the flowchart of FIG. 2, first, the vacuum chamber 2 is opened, and the two substrates 1a and 1b are loaded. In parallel or in advance, the controller 6 closes the open / close valves 51 and 52, opens the open / close valve 53, evacuates the vacuum tank 7, and achieves a high vacuum (step 2A).

  Next, the controller 6 closes the vacuum chamber 2, closes the opening / closing valve 53 and closes the opening / closing valve 52 at time T 0 shown in FIG. 3 in order to bond the two substrates 1 a and 1 b in a vacuum atmosphere. The vacuum chamber 7 is started to be evacuated by the vacuum tank 7 (step 2B).

  As a result, the inside of the vacuum chamber 2 is directly connected to the vacuum tank 7 forming a high vacuum space via the pipe 32, so that as shown by reference numeral 3A in FIG. As the evacuation proceeds, the inside of the vacuum chamber 2 is rapidly depressurized.

  Here, the volume of the vacuum tank 7 in which the evacuation speed during the evacuation time T2 from the start time T0 to the evacuation time T2 is larger than the evacuation speed by the vacuum pump 4 (indicated by the curve 3B in FIG. 3), An optimum value of the pressure (degree of vacuum) can be obtained by experiment.

  That is, even if the volume of the vacuum tank 7 is sufficiently large with respect to the vacuum chamber 2, a sufficient exhaust speed cannot be obtained if the degree of vacuum in the vacuum tank 7 is low. Further, even if the degree of vacuum in the vacuum tank 7 is sufficiently high, if the volume of the vacuum tank 7 is not sufficient, the pressure between the vacuum tank 7 and the vacuum chamber 2 is immediately obtained even if a high exhaust speed is temporarily obtained. The difference is balanced. Therefore, considering such circumstances, the volume of the vacuum tank 7 and the degree of vacuum in the vacuum tank 7 are determined to be optimum values.

  The controller 6 opens and closes the open / close valve 51 at the elapsed time T1 when the vacuum chamber 2 is depressurized from the initial atmospheric pressure state to the first pressure P1 by evacuation in the vacuum tank 7, and the vacuum pump 4 The evacuation of the vacuum chamber 2 is started (step 2C).

  Further, at time T2 when the pressure reduction has progressed and the inside of the vacuum chamber 2 has been reduced to the second pressure P2, the controller 6 closes the open / close valve 52 and terminates the evacuation by the vacuum tank 7, and thereafter the vacuum pump 4 Continue evacuation by only.

  Here, the first pressure P1 is a pressure value at which the pressure difference between the vacuum tank 7 and the vacuum chamber 2 becomes smaller and the rate of pressure drop in the vacuum chamber 2 starts to decrease. The second pressure P2 is a pressure value at which the pressure in the vacuum chamber 2 and the pressure in the vacuum tank 7 are substantially equal. Whether or not the first and second pressures P1 and P2 have been reached is determined by the controller 6 from the measured values obtained by the pressure measuring device 2a.

  After high vacuum in the vacuum chamber 2 by the vacuum pump 4, the two substrates 1a and 1b are aligned and bonded (step 2D). After the bonding operation is completed, the controller 6 The two substrates 1a and 1b bonded together by the closing operation of the opening / closing valve 51, the air introduction operation into the vacuum chamber 2, and the opening operation of the vacuum chamber 2 are carried out (step 2E).

  Subsequently, the controller 6 determines whether or not the two substrates 1a and 1b unloaded in step 2E are final substrates for the substrate bonding operation, and the two unloaded substrates 1a and 1b are final substrates ( If YES, the series of substrate bonding operations are completed, and if the two unloaded substrates 1a and 1b are not the final substrates (NO), the process returns to step 2A and the two newly bonded substrates The substrates 1a and 1b are carried in and faced to face each other (step 2F).

  As described above, according to the present embodiment, the vacuum pump 4 and the vacuum tank 7 are connected to the vacuum chamber 2 and the vacuum tank 7 is evacuated before the vacuum pump 2 is evacuated. As a result, the initial exhaust speed V0 ′ is larger than the initial exhaust speed V0 when the conventional substrate bonding apparatus is used, so that the rising characteristics at the initial exhaust speed are improved, and the vacuum in the vacuum chamber 2 is improved. The pulling time can be shortened.

  The timing of reaching the first pressure P1 and the second pressure P2 varies depending on the volume ratio between the vacuum tank 7 and the vacuum chamber 2, and the volume of the vacuum tank 7 is larger than the volume of the vacuum chamber 2. The arrival timing is earlier, and the evacuation time is greatly shortened.

  Therefore, according to the substrate bonding apparatus and the substrate bonding method of this embodiment, the time required for bonding the substrates can be greatly improved, and the productivity can be improved.

  The substrate bonding apparatus according to the first embodiment described above is configured to perform substrate bonding by connecting one vacuum pump 4 and one vacuum tank 7 to one vacuum chamber 2. Each vacuum pump and vacuum tank is connected to two (multiple) vacuum chambers, and vacuuming in the two (multiple) vacuum chambers is performed with a smaller number of vacuum pumps and vacuum tanks. It is configured to execute.

  That is, FIG. 4 is a block diagram showing a second embodiment of the substrate bonding apparatus according to the present invention in which each one vacuum pump and vacuum tank are connected to two vacuum chambers. A description will be given with reference to the graph showing the evacuation speed characteristic curve of the vacuum chamber 2 by the vacuum pump 4 and the vacuum tank 7 and the flowchart shown in FIG. In FIG. 4, the same components as those of the first embodiment shown in FIG. 1 are denoted by the same reference numerals, detailed description thereof will be omitted, and the configurations and operations different from those of the first embodiment will be mainly described. .

  In FIG. 4, the substrate bonding apparatus according to the second embodiment of the present invention includes a first vacuum chamber 21 for storing and bonding one of the two loaded substrates 11a and 11b, and the other two sheets. The second vacuum chamber 22 for storing and bonding the substrates 12a and 12b, the pressure measuring devices 21a and 22a installed in the first and second vacuum chambers 21 and 22, respectively, and the first vacuum chamber 21 include A vacuum pump 4 connected via a pipe 311 and connected to the second vacuum chamber 22 via a pipe 314, and a second vacuum connected to the first vacuum chamber 21 via a pipe 312. The vacuum tank 7 is connected to the chamber 22 via a pipe 313. The vacuum pump 4 and the vacuum tank 7 are connected via a pipe 315.

  The piping 311 is provided with an opening / closing valve 511, the piping 312 is provided with an opening / closing valve 512, the piping 313 is provided with an opening / closing valve 513, the piping 314 is provided with an opening / closing valve 514, and the piping 315 is provided with an opening / closing valve 515. .

  The open / close valves 511, 512, 513, 514, and 515 are configured to be controlled by the controller 6 together with the first and second vacuum chambers 21 and 22 and the vacuum pump 4.

  The operation and operation procedure of the substrate bonding apparatus according to the present embodiment having the above-described configuration are shown in the configuration diagram of FIG. 4, the flowchart shown in FIG. 5, and the first and second by the vacuum pump 4 and the vacuum tank 7 shown in FIG. This will be described with reference to a graph showing an exhaust velocity characteristic curve in the vacuum chambers 21 and 22. In this embodiment, it is assumed that the vacuum pump 4 is always operating.

  The substrate bonding apparatus according to this embodiment is operated according to the procedure shown in the flowchart of FIG.

  That is, the controller 6 closes the open / close valves 511, 512, 513, and 514 and opens the open / close valve 515 while the first vacuum chamber 21 is opened and the two substrates 11a and 11b are loaded. Then, the inside of the vacuum tank 7 is evacuated by the vacuum pump 4 to increase the vacuum (step 5A).

  Next, the controller 6 closes the first vacuum chamber 21 and, after the closed space is formed, closes the open / close valve 515, opens the open / close valve 512 at time T0 shown in FIG. The vacuuming of the first vacuum chamber 21 is started (step 5B).

  Thereafter, at time T1 when the inside of the first vacuum chamber 21 is depressurized to the first pressure P1 by evacuation in the vacuum tank 7, the controller 6 controls the opening of the opening / closing valve 511 and the first by the vacuum pump 4. The evacuation of the vacuum chamber 21 is started (step 5C).

  Further, the controller 6 closes the open / close valve 512 at time T2 when the vacuum pump 4 is evacuated by the vacuum pump 4 and the inside of the first vacuum chamber 21 is reduced to the second pressure P2. Then, the evacuation by the vacuum tank 7 is terminated, and the evacuation by only the vacuum pump 4 is continued thereafter.

  After the vacuum in the first vacuum chamber 21 is increased by the vacuum pump 4, the two substrates 11a and 11b are aligned and bonded (step 5D). After the bonding operation is finished, the controller 6 closes the opening / closing valve 511, the air is introduced into the vacuum chamber 21, and the first vacuum chamber 21 is opened, so that the two substrates 11a and 11b are bonded. Carrying out (step 5E) is performed.

  The controller 6 determines whether or not the two substrates 11a and 11b carried out in step 5E are final substrates for the substrate bonding operation, and the two substrates 12a and 12b carried out are the final substrates (YES). In some cases, the series of substrate bonding operations is completed, and when the two unloaded substrates 12a and 12b are not final substrates (NO), the process proceeds to Step 5G (Step 5F).

  Hereinafter, in the same procedure as the process from Step 5A to Step 5F for the first vacuum chamber 21, as shown in parentheses in FIG. 5, the substrates 12a and 12b into the second vacuum chamber 22 are shown. Loading, evacuation of the second vacuum chamber 22, bonding of the substrates 12a and 12b, unloading, and determination of whether or not the substrate is the final substrate are sequentially performed (steps 5G to 5L).

  If it is determined in step 5L that the final substrate is not the final substrate (NO), the process proceeds to step 5A.

  As described above, according to the present embodiment, one vacuum pump 4 and one vacuum tank 7 are configured to be shared by the first and second vacuum chambers 21 and 22. Compared to the configuration in which one vacuum pump and one vacuum tank are connected to one vacuum chamber, the space for installing the vacuum pump and the vacuum tank is small, and space saving can be realized.

  In the second embodiment, one vacuum pump and one vacuum tank are connected to and operated by two vacuum chambers, but are connected to and operated by three or more vacuum chambers. You may comprise.

  In the second embodiment, the first and second vacuum chambers 21 and 22 in the vacuum tank 7 are evacuated at different timings. However, the first and second vacuum chambers 21 and 22 are The vacuum tank 7 may be evacuated simultaneously. In this case, it is preferable to use a vacuum tank having a larger volume than when the first and second vacuum chambers 21 and 22 are evacuated at different timings.

  In the first and second embodiments of the substrate bonding apparatus and the substrate bonding method described above, the vacuum tank 7 may be anything as long as it can form a vacuum space. Piping may be used.

  The vacuum tank is evacuated in the example in which the substrate is carried in parallel with the operation of carrying the substrate into the vacuum chamber. However, the vacuum pump is used to evacuate the vacuum chamber. You can do it while you are not. Therefore, in addition to the operation of loading the substrate into the vacuum chamber, it may be performed in parallel with the operation of releasing the inside of the vacuum chamber to atmospheric pressure in Step 2E of FIG. 2 and Step 5E (5K) of FIG. good. In addition, it may be performed in parallel with the operation of bonding the substrates in the vacuum chamber in Step 2D of FIG. 2 and Step 5D (5J) of FIG. When vacuuming of the vacuum tank is performed in parallel with the operation of bonding the substrates in the vacuum chamber, the vacuum pump that has been kept open in step 2D in FIG. 2 and step 5D (5J) in FIG. It is necessary to close the open / close valve between the vacuum chamber (open / close valve 51 in FIG. 1 and open / close valves 511 and 514 in FIG. 4).

  Moreover, although the vacuum pump which evacuates the inside of a vacuum tank was demonstrated by the example which combines with the vacuum pump which evacuates the inside of a vacuum chamber, you may provide a vacuum pump separately in a vacuum tank and a vacuum chamber. In this case, the vacuum tank can be evacuated in parallel even while the vacuum chamber is evacuated by the vacuum pump, so that the vacuum tank can be evacuated efficiently, and the substrate bonding apparatus The productivity can be further improved.

  Further, the opening / closing valve provided in the pipe connecting the vacuum chamber and the vacuum tank has been described as opening and closing the pipe. However, a variable flow rate opening / closing valve having a function of adjusting the flow rate may be used. In this way, since the flow rate can be adjusted in addition to the opening operation of the pipe, the rise of the exhaust speed at the start of pressure reduction in the vacuum chamber by the vacuum tank can be controlled. As a result, even if dust rises in the vacuum chamber due to the sudden flow of gas in the vacuum chamber that occurs when the open / close valve is fully opened at the initial stage of exhaust, the rise of the exhaust speed can be controlled. The rise of dust in the vacuum chamber can be suppressed, and the display quality of a liquid crystal display panel or the like manufactured by bonding two substrates can be improved.

It is a block diagram which shows the 1st Example of the board | substrate bonding apparatus of this invention. It is a flowchart which shows the operation procedure of the board | substrate bonding apparatus shown in FIG. It is the graph which showed the exhaust speed characteristic curve in the vacuum chamber shown in FIG. It is a block diagram which shows the 2nd Example of the board | substrate bonding apparatus of this invention. It is a flowchart which shows the operation procedure of the board | substrate bonding apparatus shown in FIG. It is a block diagram which shows the conventional board | substrate bonding apparatus. It is the graph which showed the exhaust speed characteristic curve in the vacuum chamber shown in FIG.

Explanation of symbols

1a, 1b, 11a, 11b, 12a, 12b Substrate 2 Vacuum chamber 21 First vacuum chamber 22 Second vacuum chamber 2a, 21a, 22a Pressure measuring device 3, 31, 32, 33, 311, 312, 313, 314 315 Piping 4 Vacuum pump 5, 51, 52, 53, 511, 512, 513, 514, 515 Open / close valve 6 Controller 7 Vacuum tank

Claims (4)

In a substrate laminating apparatus for laminating two substrates held opposite to each other in a vacuum chamber having a reduced pressure,
Coupled to said vacuum chamber, a vacuum tank vacuum evacuable,
A vacuum pump connected to said vacuum chamber,
Selectively and communicatively opening and closing valve between said vacuum pump and between the vacuum chamber and said vacuum tank and the vacuum chamber,
After starting the evacuation of said vacuum chamber by said vacuum tank, said even before the evacuation is completed by vacuum tank, vacuum within the vacuum chamber by evacuation by the vacuum tank to a predetermined first pressure and control means for switching control of the opening and closing valve so as to initiate the evacuation of the vacuum chamber by the vacuum pump at the time of the,
A substrate bonding apparatus comprising: The on- off valve is
A first on-off valve provided in the first pipe for connecting the vacuum pump and the vacuum chamber, and the second on-off valve provided in the second pipe connecting the said vacuum tank and the vacuum chamber, and a third on-off valve provided in the third pipe connected to the vacuum tank is branched from the first pipe between the vacuum pump and the first on-off valve,
The control means includes
The first, the second on-off valve closed, in the third state of the opening and closing valve in the open was evacuated the vacuum tank, the third on-off valve closed, and the second on-off valve in the open start the evacuation of the vacuum chamber by the vacuum tank Te,
In a state in which the vacuum chamber is reduced to a predetermined first pressure, and the first on-off valve is opened, to start the evacuation of the vacuum chamber by the vacuum pump,
Once reduced to a predetermined second pressure to proceed under reduced pressure from the first pressure, to terminate the evacuation by the vacuum tank said second opening and closing valve in the closed, evacuated by the vacuum pump only Run the
The board | substrate bonding apparatus of Claim 1 characterized by the above-mentioned. Carrying two substrates into a vacuum chamber and arranging them vertically opposite to each other;
After this step, a first evacuation step of evacuating the vacuum chamber by a vacuum tank,
After the first evacuation step is started and before the first evacuation step is completed, when the vacuum chamber is depressurized to a predetermined first pressure by evacuation by the vacuum tank. a second vacuum step of evacuating the vacuum chamber by the vacuum pump,
After the first evacuation step and the second vacuum step, a step of bonding the two substrates in the vacuum chamber,
After this step, bonding method substrate characterized by comprising the step of unloading the two sheets of substrates bonded by returning the vacuum chamber to atmospheric pressure from the vacuum chamber. It said vacuum tank, a substrate bonding method according to claim 3, further comprising the step of evacuating the said vacuum pump.

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