JPH07193117A - Board holding device - Google Patents

Abstract

PURPOSE:To reduce electrostatic charge generated when a board is stripped from a mounting surface by preparing in a board holding part suction ports to suck the board by means of a negative pressure means and a board mounting surface whose contact part with the board has a specific volume resistivity. CONSTITUTION:In a board holding device, when a board W is mounted on a board mounting surface 12, a suction port 17 is negatively pressurized by a vacuum pump 21 so as to suck/hold the board W. When the board W is to be separated from a board holding part 10, the pump 21 releases the negative pressure. At the time of separation, supposing that the volume resistivity of the board W at 250 deg.C is 10YOMEGAcm, a contact part of the surface 12 with the board W has a volume resistivity of more than 10Y<-1> at the same temperature, that is, the same volume resistivity as that of the board W, so that less charge moves between the board W and the surface 12. Therefore stripping charge is hardly generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a substrate holding device, and more particularly,
The present invention relates to a substrate holding device that sucks and holds a substrate.

[0002]

2. Description of the Related Art A substrate processing apparatus for performing various kinds of processing on a rectangular substrate (a glass substrate for a liquid crystal, a glass substrate for a photomask, a ceramic substrate for manufacturing a thermal head, etc.) or a circular substrate for a semiconductor is known. Has been. As this type of substrate processing apparatus, a heating / cooling apparatus for heating / cooling a substrate,
A rotary substrate processing apparatus (spin coater, developing processing apparatus, cleaning processing apparatus, etc.) that rotates and processes a substrate, a substrate transfer apparatus that transfers the substrate between the processing apparatuses, and the like are known. Each of these devices usually includes a substrate holding device that sucks and holds a substrate.

This substrate holding device is provided with a substrate holding portion for holding the substrate on a substrate mounting surface having an adsorption opening for adsorbing the substrate, and a negative pressure generating portion for making the adsorption opening a negative pressure.
In this substrate holding device, when the substrate is placed on the substrate placement surface, the negative pressure generating unit applies a negative pressure to the suction port to suck and hold the substrate.

[0004]

In the conventional substrate holding device, when a high dielectric substrate such as a non-alkali glass substrate used as a substrate for an active matrix type liquid crystal display device is adsorbed, the adsorption is released. Then, when the substrate is separated from the substrate mounting portion, strong peeling charge is generated. When static electricity is generated, the surface layer of the substrate is destroyed or particles in the air adhere to the substrate.

An object of the present invention is to reduce the peeling charge that occurs when a substrate is peeled from its mounting surface in a substrate holding device that sucks and holds the substrate.

[0006]

A substrate holding device according to the present invention is a device for sucking and holding a substrate, and is provided with a substrate holding portion and negative pressure means. The substrate holding part has a suction port for sucking the substrate and a 250 part of the contact part with the substrate when the volume resistivity of the substrate at 250 ° C. is 10 ^Y Ωcm.
The substrate mounting surface has a volume resistivity at 10 ° C. of 10 ^{Y −1} Ωcm or more. The negative pressure means makes the suction port a negative pressure.

[0007]

In the substrate holding apparatus according to the present invention, when the substrate is placed on the substrate placement surface, the negative pressure means applies a negative pressure to the suction port to suck and hold the substrate. When the substrate is separated from the substrate holder, the negative pressure by the negative pressure means is released. At the time of this separation, the volume resistivity of the substrate at 250 ° C was set to 10 ^Y.
If Ωcm, the contact portion of the substrate mounting surface with the substrate is 250
Since the volume resistivity at 10 ° C. is 10 ^{Y −1} or more, the volume resistivity is the same as that of the substrate, and the movement of charges between the substrate and the substrate mounting surface is small. Therefore, peeling charge hardly occurs.

[0008]

1 and 2, a substrate processing apparatus 1 adopting an embodiment of the present invention forms a thin film of photoresist on a square substrate W made of non-alkali glass for an active matrix liquid crystal display device. It is a device that does. The substrate processing apparatus 1 includes a substrate loading / unloading unit 2 for mounting two cassettes C1 and C2 containing a large number of substrates W, a processing unit unit 3 for performing a series of processes on the substrate W, and a substrate loading / unloading unit. It has a substrate transport unit 4 that transports the substrate W between the unloading unit 2 and the processing unit unit 3.

The substrate loading / unloading section 2 includes cassettes C1 and C.
The indexer ID for loading / unloading the substrate W stored in 2 and the substrate W between the position facing the cassettes C1 and C2 and the substrate loading / unloading position with respect to the substrate transport unit 4
The indexer robot RB1 conveys the sheets one by one. For example, 10 substrates W can be stored in the cassettes C1 and C2. The indexer ID has a function of moving the mounted cassettes C1 and C2 up and down to maintain the substrate take-out / take-in position at a constant height. The indexer robot RB1 can move on the rail 5 arranged in the Y direction (depth direction in FIG. 1). The indexer robot RB1 is a scalar type robot and can move in the Z direction (vertical direction in FIG. 1), the X direction (horizontal direction in FIG. 1), and the θ direction (rotational direction around the vertical axis). is there.

In the processing unit section 3, the respective processing sections are arranged at the upper and lower sides.
It is arranged in columns. A spin scrubber SS for cleaning the substrate W and a spin coater SC for applying a photoresist solution to the cleaned substrate W are arranged in the lower stage thereof. On the upper side, hot plates HP1, H
P2 and cool plates CP1 and CP2 are arranged. The hot plate HP1 is for dehydrating and baking the substrate W cleaned by the spin scrubber SS, and the hot plate HP2 is for pre-baking the substrate W coated with the photoresist solution.

The substrate transfer section 4 has a rail 6 extending in the X direction.
It has a substrate transfer robot RB2 that can move above.
The substrate transfer robot RB2 is a SCARA type robot and is also movable in the Z direction and the Y direction. Both hot plates HP1 and HP2 have the same structure, and both cool plates CP1 and CP2 have the same structure. Here, the hot plate HP1 and the cool plate CP1 will be described as an example.

The hot plate HP1 has a plate-shaped substrate holding portion 10 as shown in FIGS. The substrate holding unit 10 has an aluminum heating plate 11 as a heating plate having a heating means such as a plate heater, and a substrate mounting surface 12 coated on the heating plate 11. The material of the substrate mounting surface 12 may be one having a volume resistivity of 10 ¹² (Ωcm) or more at 250 ° C., more preferably 10 ¹³ to 10 ¹⁵ (Ωcm), and is, for example, non-alkali glass. .

The substrate holding portion 10 has three through holes 13 arranged at the vertices of a regular triangle in plan view.
It is formed through 2. Through this through hole 13,
The substrate support pin 14 is provided so as to be able to move up and down. The lower end of the substrate support pin 14 is integrally attached to the pin attachment member 15. The pin mounting member 15 is an air cylinder 16
The substrate support pins 14 move up and down as the air cylinder 16 expands and contracts. In the hot plate HP1, the substrate transport robot RB2 loads and unloads the substrate W with the substrate support pins 14 raised. Also,
By lowering the substrate support pins 14, the substrate W is placed on the substrate placement surface 12 of the substrate holding unit 10.

Further, the substrate holding portion 10 is formed with four suction ports 17 arranged at the positions of the vertices of a square in plan view. These suction ports 17 communicate with a suction pipe 19 connected to the side surface of the heating plate 11 via a suction passage 18 formed in the heating plate 11. An electromagnetic opening / closing valve 20 is arranged in the middle of the adsorption pipe 19. A vacuum pump 21 is connected to the end of the adsorption pipe 19.

The cool plate CP1 has a flat plate-shaped substrate mounting portion 30. The substrate platform 30 includes a heat transfer plate 31 made of aluminum and a water cooling plate 3 made of aluminum.
2 and a Peltier element 33 for rapid cooling interposed between the heat transfer plate 31 and the water cooling plate 32. Further, the through-hole 1 similar to the substrate holding unit 10 is also provided in the substrate placing unit 30.
3 is formed, and the substrate support pin 14 is provided so as to be able to move up and down through the through hole 13. The substrate support pin 14 is interlockingly connected to the air cylinder 16 via a pin mounting member 15.

Next, the operation of the above embodiment will be described. The cassettes C1 and C2 storing the substrate W carry in the substrate.
When placed on the carry-out section 2, the indexer robot RB1 takes out the substrates W one by one from the cassettes C1 and C2 and transfers them to the substrate transfer robot RB2. Substrate transfer robot RB2
Transports the received substrate W to the spin scrubber SS. The spin scrubber SS cleans the received substrate W. The substrate W that has undergone the cleaning process is transported to the hot plate HP1.

In the hot plate HP1, the substrate support pins 14 which are previously arranged in the raised position by the air cylinder 16 are provided.
Then, the substrate W is received from the substrate transfer robot RB2. Upon receiving the substrate W, the hot plate HP1 lowers the substrate support pins 14 by the air cylinder 16 and mounts the substrate W on the substrate mounting surface 12 of the substrate holding unit 10. Subsequently, the electromagnetic opening / closing valve 20 is opened, and the suction port 17 is set to a negative pressure by the vacuum pump 21 to suck and hold the substrate W. In this state, the substrate W is heated by the heating plate 11 and dehydrated and baked.

When the dehydration bake process is completed, the electromagnetic on-off valve 20 is closed to release the adsorption, and the substrate support pin 14 is released.
Is lifted by the air cylinder 16 and the substrate W is separated upward from the substrate mounting surface 12. At this time, the substrate mounting surface 12
Has a volume resistivity equivalent to that of the substrate W, and therefore peeling charging is unlikely to occur. For this reason, the adhesion of particles and the destruction of the substrate surface layer due to peeling electrification hardly occur.

The substrate W raised by the substrate support pins 14 is received by the substrate transfer robot RB2 and transferred to the cool plate CP1. Cool plate CP1
Then, the substrate W is received by the substrate support pins 14 and placed on the substrate holder 30. Then, the substrate W heated by the hot plate HP1 is cooled to room temperature. The substrate W for which the cooling process has been completed is raised by the substrate support pins 14,
It is received by the substrate transfer robot RB2.

The substrate W received by the substrate transfer robot RB2 is transferred to the spin coater SC. In the spin coater SC, the photoresist liquid is applied onto the substrate W. The substrate W coated with the photoresist solution is transported to the hot plate HP2 and prebaked. Here again, peeling charging is unlikely to occur during substrate separation. The substrate W for which the pre-baking has been completed is transferred to the cool plate CP1 and cooled to room temperature. The substrate W for which the cooling process has been completed is transferred to the indexer robot RB1 of the substrate loading / unloading unit 2 by the substrate transport robot RB2 and is stored in the cassettes C1 and C2.

Experimental Example An experimental example of the present invention is shown below.
The glass substrate used in the experiment is a non-alkali glass substrate made of barium borosilicate having a product name of 7059 manufactured by Corning Incorporated, and has a volume resistivity of 10 ¹³ to 250 at 250 ° C.
It was 10 ¹⁴ (Ωcm). Used hot plate HP
The material of the substrate holder 10 of No. 1 is shown in Table 1 below.

[0022]

[Table 1]

From the test results summarized in Table 1, the volume resistivity of the substrate holder 10 at 250 ° C. is 250 ° C. of the substrate.
It was found that when it is 10 ¹⁴ Ωcm or more, which is equivalent to the volume resistivity in, the effect of suppressing static electricity is obtained. Therefore, considering the variation in volume resistivity of the alkali-free glass at 250 ° C., the volume resistivity of the substrate mounting surface 12 at 250 ° C. may be 10 ¹² (Ωcm) or more, more preferably 10 ¹³ to It was found that 10 ¹⁵ (Ωcm) was sufficient.

Other Embodiments (a) The present invention is not only effective when the substrate is made of non-alkali glass as described above, but can be applied to other substrates. That is, the substrate temperature of 250 ° C
At a volume resistivity of 10 ^Y Ωcm, the temperature of the material constituting the substrate mounting surface on which the substrate is mounted is 250 ° C.
It is sufficient that the volume resistivity at is 10 ^Y-1 Ωcm or more. For example, when soda lime glass having a volume resistivity of 10 ⁶ Ωcm at 250 ° C. is used as the substrate, 250 of the material forming the substrate mounting surface on which the substrate is mounted is used.
The volume resistivity at ° C may be 10 ⁵ Ωcm or more, and the substrate mounting surface may be formed of soda lime glass, for example. If the substrate mounting surface is formed of the same kind of material as the substrate, the volume resistivity thereof is almost the same as the volume resistivity of the substrate, so that it is possible to suppress the occurrence of peeling charging, but it is not always the same kind of material as the substrate. It is not necessary to form the substrate mounting surface by the above, and if the volume resistivity at 250 ° C. is substantially equal to or higher than the volume resistivity at 250 ° C. of the substrate, the material may not be the same as the material of the substrate. (B) Not only hot plates HP1 and HP2,
The present invention may be applied to a substrate suction holding unit of another substrate processing apparatus such as a spin scrubber SS or a spin coater SC. (C) As the substrate mounting surface 12, silicon carbide or aluminum oxide may be used instead of the alkali-free glass. (D) The substrate mounting surface 12 may be formed at least in the substrate contact portion. The forming method is not limited to coating, and a plate-shaped material may be adhered or fixed by a fixing member.

[0025]

The substrate holding device according to the present invention has a volume resistivity of 10 ^{Y -1} (Ω at a temperature of 250 ° C. at the portion in contact with the substrate.
cm) or more, the peeling electrification hardly occurs.

[Brief description of drawings]

FIG. 1 is a schematic side view of a substrate processing apparatus adopting an embodiment of the present invention.

FIG. 2 is a schematic plan view thereof.

FIG. 3 is a vertical sectional view of a hot plate and a cool plate.

FIG. 4 is a schematic perspective view of a hot plate.

[Explanation of symbols]

 10 substrate holding part 12 substrate mounting surface 17 suction port 21 vacuum pump

Claims (1)

[Claims] 1. A substrate holding device for holding a substrate by suction, comprising: a suction port for sucking the substrate; and 250 of the substrate.
When the volume resistivity at 10 ° C. is 10 ^Y Ωcm, the volume resistivity at 250 ° C. of the contact portion with the substrate is 10 ^Y-1.
A substrate holding device comprising: a substrate holding part having a substrate mounting surface of Ωcm or more; and negative pressure means for making the suction port a negative pressure.