JP4408786B2 - Vacuum drying apparatus and vacuum drying method - Google Patents

Description

The present invention relates to a vacuum drying apparatus and a vacuum drying method .

For example, Patent Document 1 discloses a vacuum drying apparatus for drying a thin film such as a photoresist applied to a substrate such as a semiconductor wafer, a glass substrate for a liquid crystal display panel, or a mask substrate for a semiconductor manufacturing apparatus under reduced pressure. In the reduced-pressure drying apparatus described in Patent Document 1, the inside of the chamber into which the substrate is loaded is decompressed by a vacuum pump, thereby promoting the evaporation of the solvent that is the center of the resist solution component and quickly drying the photoresist. I am doing so. When the photoresist is dried using such a reduced pressure drying apparatus, it is possible to prevent the influence of external factors such as wind and heat, and to dry the photoresist evenly.
JP-A-7-283108

  When such a vacuum drying apparatus is used, a phenomenon called bumping may occur immediately after the vacuum drying process is started. This is a phenomenon that occurs when the solvent component in the photoresist applied to the substrate surface suddenly evaporates and suddenly boils. When such bumping occurs, a phenomenon called small bubbles is formed on the surface of the photoresist called defoaming, and the substrate cannot be used.

  For this reason, in the initial stage of the reduced-pressure drying process, it is necessary to exhaust air at a lower speed than in the chamber to prevent the occurrence of defoaming. On the other hand, in order to perform quick and uniform drying over the entire surface of the substrate, it is necessary to exhaust the air more strongly than in the chamber.

  For this purpose, in order to control the exhaust amount from the inside of the chamber, it is necessary to dispose an exhaust amount adjusting member such as a damper or a flow rate variable valve, which increases the manufacturing cost of the apparatus. At this time, when an exhaust amount adjusting member that can continuously change the exhaust amount is used, the cost is particularly high.

The present invention has been made to solve the above problems, and provides a reduced pressure drying apparatus and a reduced pressure drying method capable of easily changing the exhaust amount from the chamber without using a special exhaust amount adjusting member. The purpose is to do.

According to a first aspect of the present invention, there is provided a vacuum drying apparatus for drying a thin film formed on a main surface of a substrate under reduced pressure, a chamber covering the periphery of the substrate, and a plurality of lifting members that contact the lower surface of the substrate and support the substrate And an exhaust port formed in the chamber, an exhaust means for exhausting air through the exhaust port, and the plurality of elevating members, and at a position facing the opening on the chamber side in the exhaust port. By moving up and down together with the elevating member, a support plate that changes the amount of exhaust from the exhaust port by changing the distance from the exhaust port , and a substrate disposed in the chamber, the substrate is removed when drying the substrate under reduced pressure. A plurality of supporting members to be supported; and an elevating means for elevating and lowering the support plate, and when the substrate is transferred between the elevating member and the support member by an elevating operation of the support plate. In, wherein the supporting substrate by the supporting member at the time of vacuum drying.

According to a second aspect of the present invention, in the first aspect of the present invention, the exhaust port is formed at a position overlapping the support plate in a plan view on the bottom surface of the chamber.

According to a third aspect of the present invention, there is provided a vacuum drying method for exhausting air from an exhaust port formed in a chamber covering the periphery of the substrate and drying the thin film formed on the main surface of the substrate disposed in the chamber under reduced pressure. A step of opening the chamber by raising the lid portion of the chamber, and moving up and down at a position facing the opening on the chamber side in the exhaust port, thereby changing the distance from the exhaust port. A step of raising a support plate for changing the exhaust amount from the exhaust port to a delivery position of the substrate, and supporting the substrate by an elevating member disposed on the support plate; and the lower surface of the support plate To the first drying position where the distance between the exhaust port and the opening on the chamber side is small, and the substrate supported by the elevating member is lowered by the lowering operation of the support plate. A step of transferring to a support member disposed in the chamber; a step of lowering the lid of the chamber to close the chamber; and a step of exhausting air from the exhaust port to depressurize the chamber. Elevating the support plate to a second drying position where a distance between the lower surface of the support plate and the opening on the chamber side at the exhaust port is greater than the first drying position; Stopping the exhaust from the exhaust port, raising the lid of the chamber to open the chamber, and raising the support plate to the substrate delivery position, thereby supporting the substrate supported by the support member, And a step of supporting by a plurality of elevating members arranged on the support plate.

According to the first and third aspects of the invention, since the exhaust amount from the exhaust port is changed using the support plate that moves up and down together with the elevating member, a special exhaust amount adjusting member is not used. It becomes possible to easily change the exhaust amount from the chamber.

Moreover , it becomes possible to easily change the exhaust amount from the chamber by using a support plate for connecting a plurality of elevating members . And since this support plate performs the raising / lowering operation | movement of the raising / lowering member for performing delivery of a board | substrate between support members, and also changes an exhaust_gas | exhaustion amount, the delivery of a board | substrate and the change of an exhaust_gas | exhaustion amount are the same. It is possible to change the exhaust amount from the chamber more easily.

According to the second aspect of the present invention, since the exhaust port is formed at a position overlapping the support plate in plan view, the installation area of the chamber can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1 to 3 are schematic views of a vacuum drying apparatus according to the first embodiment of the present invention, and FIG. 4 is an enlarged view of the vicinity of an opening on the chamber 10 side in the exhaust port 31.

  In this vacuum drying apparatus, a chamber 10 including a lid portion 11, a packing 12, and a base portion 13, a support pin 15 erected on the base portion 13 in the chamber 10, and a plurality of elevating pins 21 are erected. And a support plate 22. The substrate W is supported in the chamber 10 by the support pins 15 or the lift pins 21 in a horizontal posture with its main surface facing upward. In addition, the raising / lowering pin 21 comprises the support member based on this invention, and the support plate 22 comprises the shielding member based on this invention which connects the several raising / lowering pin 21. As shown in FIG.

  An exhaust port 31 is formed in the base portion 13 of the chamber 10. The exhaust port 31 is formed at a position overlapping the support plate 22 in a plan view of the base portion 13 constituting the bottom surface of the chamber 10. The exhaust port 31 is connected to a vacuum pump 34 by a pipe line 32. An opening / closing valve 33 is disposed between the exhaust port 31 and the vacuum pump 34. An exhaust fan or the like may be used instead of the vacuum pump 34.

  The support plate 22 is connected to the lifting mechanism 25 via a support bar 24. The lift pins 21, together with the support plate 22, by the action of the lift mechanism 25, the transfer position of the substrate W between the transfer arm (not shown), the first and second drying positions having different heights, respectively. It is possible to move up and down between the height positions.

  Next, a drying operation for drying the thin film formed on the main surface of the substrate by the reduced pressure drying apparatus will be described. 5 and 6 are flowcharts showing a drying operation by the reduced pressure drying apparatus according to the first embodiment of the present invention.

  When drying the thin film formed on the main surface of the substrate W, first, as shown in FIG. 1, the lid portion 11 in the chamber 10 is raised by an elevating mechanism (not shown) to open the chamber 10 (step S11). ). Next, a transfer arm (not shown) that supports the substrate W enters the chamber 10 (step S12).

  Next, by the driving of the elevating mechanism 25, the elevating pins 21 are raised together with the support plate 22 to the delivery position of the substrate W shown in FIG. 1 (step S13). As a result, the substrate W supported by the transport arm is supported by the lift pins 21. Then, the transfer arm leaves the chamber 10 (step S14).

  Next, by driving the lifting mechanism 25, the lifting pins 21 are lowered together with the support plate 22 to the first drying position shown in FIG. 2 (step S15). As a result, the substrate W whose lower surface is supported by the lift pins 21 is transferred to the support pins 15. Then, as shown in FIG. 2, the lid portion 11 in the chamber 10 is lowered by an elevator mechanism (not shown) to close the chamber 10 (step S16). In this state, as shown in FIG. 2, the distance D (see FIG. 4) between the lower surface of the support plate 22 and the opening 35 on the chamber 10 side in the exhaust port 31 is small.

  In this state, the on-off valve 33 is opened and exhaust is performed by the action of the vacuum pump 34 (step S17). At this time, in this vacuum drying apparatus, the exhaust port 31 is formed at the bottom of the chamber 10, and the distance between the main surface of the substrate W and the lower surface of the lid 11 of the chamber 10 is set small. For this reason, when exhaust is performed from the exhaust port 31, an air flow from the center toward the edge is generated on the main surface of the substrate W.

  In this state, the distance D between the lower surface of the support plate 22 and the opening 35 on the chamber 10 side in the exhaust port 31 is set small. For this reason, the exhaust amount from the exhaust port 31 is small regardless of the exhaust force by the vacuum pump 34. At this time, the distance D between the lower surface of the support plate 22 and the opening 35 on the chamber 10 side at the exhaust port 31 is preferably 10 mm or less, and more preferably 4 mm or less.

  In this way, when the distance between the main surface of the substrate W and the lid portion 11 in the chamber 10 is set to be small and vacuum drying is performed with a small exhaust amount, the center of the main surface of the substrate W is shifted from the center to the edge. Appropriate drying under reduced pressure can be performed in a state in which defoaming due to bumping is prevented by the gentle air flow that is directed. However, the thin film portion at the center of the main surface of the substrate W cannot be sufficiently dried.

  When a predetermined time has elapsed since the first drying step described above has been started (step S18), the elevating pins 21 are raised together with the support plate 22 to the second drying position shown in FIG. 3 (step S19). As a result, the distance D between the lower surface of the support plate 22 and the opening 35 on the chamber 10 side at the exhaust port 31 is increased, and the exhaust amount from the exhaust port 31 is increased. At this time, a relatively large air flow is generated on the main surface of the substrate W from the center toward the edge. When vacuum drying is performed with such a large displacement, drying is performed quickly over the entire main surface of the substrate W. However, since the thin film is dried to some extent in the first drying step described above, defoaming due to bumping does not occur.

In the second drying step described above, if detected that the degree of vacuum Chang Ba 1 in 0 by a non-illustrated sensor has reached the preset value (step S20), and closes the on-off valve 33 (step S21). Then, nitrogen gas is purged into the chamber 10 (step S22).

If Chang Ba 1 within 0 and atmospheric pressure, is raised by the elevating mechanism not shown the lid portion 11 in the chamber 10, to open the chamber 10 (step S23). Next, by the driving of the elevating mechanism 25, the elevating pins 21 are raised together with the support plate 22 to the delivery position of the substrate W shown in FIG. 1 (step S24).

In this state, a transfer arm (not shown) enters the chamber 10 (step S25). And by the drive of the raising / lowering mechanism 25, the raising / lowering pin 21 falls with the support plate 22 (step S26). Thereby, the board | substrate W currently supported by the raising / lowering pin 21 is supported by the conveyance arm. Then, the transfer arm that supports the substrate W leaves the chamber 10 (step S27).
FIG. 7 is an explanatory diagram showing changes in the degree of vacuum in the chamber 10 during the above-described reduced-pressure drying operation.

  In this figure, the vertical axis represents time (seconds), and the vertical axis represents the degree of vacuum (Torr) in logarithm. Region A is a first drying process in which the distance D between the lower surface of the support plate 22 and the opening 35 on the chamber 10 side at the exhaust port 31 is reduced to perform exhaust with a small exhaust amount, and region B is the lower surface of the support plate 22. Region C indicates a second drying step in which the distance D between the exhaust port 31 and the opening 35 on the chamber 10 side is increased to perform exhaust with a large exhaust amount, and region C indicates a purge step with nitrogen gas. Moreover, the code | symbol P has shown atmospheric pressure.

  As described above, according to the vacuum drying apparatus of the present invention, it is possible to easily change the exhaust amount from the chamber without using a special exhaust amount adjusting member such as a flow rate adjusting valve.

  Next, another embodiment of the present invention will be described. FIG. 8 is an enlarged view of the vicinity of the opening on the chamber 10 side of the exhaust port 31 in the vacuum decompression apparatus according to the second embodiment.

In this embodiment, at a position opposite to the exhaust port 31 in the lower surface of the support plate 22 has a tapered surface facing downward, approach can be projections on Chan Ba 1 0 side of the opening 35 at the exhaust port 31 The point which added 36 differs from 1st Embodiment mentioned above. In this embodiment, the exhaust amount from the exhaust port 31 can be finely adjusted.

  Next, still another embodiment of the present invention will be described. FIG. 9 is an enlarged view of the vicinity of the opening on the chamber 10 side of the exhaust port 31 in the vacuum decompression apparatus according to the third embodiment.

  In this embodiment, the support plate 22 in the first and second embodiments is omitted, and a plurality of lifting pins 21 are connected by a linear connecting member 38. A plate-shaped shielding portion 37 is disposed at a position facing the exhaust port 31 in the connecting member 38. Also in this embodiment, the exhaust amount from the exhaust port 31 can be adjusted as in the first embodiment described above.

  In the first and second embodiments described above, the exhaust port 31 is formed at a position overlapping the support plate 22 in a plan view of the base portion 13 constituting the bottom surface of the chamber 10. However, the exhaust port is formed at a position that does not overlap with the support plate 22 in plan view, and a shielding portion that is connected to the support plate by a linear connecting member similar to that of the third embodiment is disposed above the exhaust port. A configuration may be employed. However, when the exhaust port 31 is formed at a position overlapping the support plate 22 in plan view, the installation area of the chamber can be reduced.

In each example set above mentioned, both the lifting pins 21 a first, but running vacuum dried is stopped at the second drying position, the second drying the elevating pins 21 from the first drying position You may make it perform drying, moving continuously to a position. Then, the exhaust speed can be changed more continuously.

1 is a schematic diagram of a vacuum drying apparatus according to a first embodiment of the present invention. 1 is a schematic diagram of a vacuum drying apparatus according to a first embodiment of the present invention. 1 is a schematic diagram of a vacuum drying apparatus according to a first embodiment of the present invention. 4 is an enlarged view of the vicinity of an opening on the chamber 10 side in an exhaust port 31. FIG. It is a flowchart which shows drying operation. It is a flowchart which shows drying operation. It is explanatory drawing which shows the change of the vacuum degree in the chamber 10 at the time of pressure reduction drying operation. It is an enlarged view near the opening part by the side of the chamber 10 of the exhaust port 31 in the vacuum decompression device concerning 2nd Embodiment. It is an enlarged view near the opening part by the side of the chamber 10 of the exhaust port 31 in the vacuum decompression device concerning 2nd Embodiment.

10 the chamber 11 the lid portion 12 Packing 13 base 14 upper surface 15 supporting pin
2 1 Lift pin 22 Support plate 31 Exhaust port 32 Pipe line 33 Open / close valve 34 Vacuum pump 35 Opening portion 36 Protruding portion 37 Shielding portion 38 Connecting member 41 Plate member 43 Air cylinder W Substrate

Claims (3)

In a vacuum drying apparatus for vacuum drying a thin film formed on a main surface of a substrate,
A chamber covering the periphery of the substrate;
A plurality of elevating members that contact the lower surface of the substrate and support the substrate;
An exhaust port formed in the chamber;
An exhaust means for exhausting air through the exhaust port;
With connecting the plurality of elevating members, by vertically movable together with the lifting member at a position facing the opening of the chamber side of the exhaust port, from the exhaust port by changing the distance between the exhaust port A support plate for changing the displacement of
A plurality of support members disposed in the chamber and supporting the substrate when the substrate is dried under reduced pressure;
Elevating means for elevating and lowering the support plate,
A reduced-pressure drying apparatus characterized in that the substrate is transferred between the elevating member and the support member by the elevating operation of the support plate, and the substrate is supported by the support member during reduced-pressure drying. The vacuum drying apparatus according to claim 1 ,
The exhaust port is a vacuum drying apparatus formed at a position overlapping the support plate in a plan view on the bottom surface of the chamber. In a vacuum drying method of exhausting air from an exhaust port formed in a chamber covering the periphery of the substrate, and drying the thin film formed on the main surface of the substrate disposed in the chamber under reduced pressure,
Raising the lid of the chamber to open the chamber;
A support plate for changing the amount of exhaust from the exhaust port by changing the distance from the exhaust port by moving up and down at a position facing the opening on the chamber side in the exhaust port is a substrate transfer position. A step of supporting the substrate by a lifting member disposed on the support plate,
The support plate is lowered to the first drying position where the distance between the lower surface of the support plate and the opening on the chamber side at the exhaust port is small, and is supported by the elevating member by the lowering operation of the support plate. Transferring the substrate to a support member disposed in the chamber;
Lowering the chamber lid and closing the chamber;
Exhausting from the exhaust port and depressurizing the chamber;
Raising the support plate to a second drying position where the distance between the lower surface of the support plate and the opening on the chamber side at the exhaust port is greater than the first drying position;
Stopping the exhaust from the exhaust port, raising the lid of the chamber and opening the chamber;
Supporting the substrate supported by the support member on a plurality of elevating members disposed on the support plate by raising the support plate to a delivery position of the substrate;
A reduced-pressure drying method comprising:

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