JP3592934B2 - Coating method and coating device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a coating apparatus and a coating method such as a resist coating apparatus incorporated in an LCD manufacturing system that manufactures a liquid crystal display device (hereinafter, the liquid crystal display device is referred to as “LCD”) using, for example, photolithography technology.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a coating apparatus that forms a resist film by applying a resist agent on an LCD glass substrate (hereinafter, the LCD glass substrate is simply referred to as a “substrate”), the center of the substrate held by a spin chuck is used. After the resist solution was dropped, the spin chuck and the coater cup were moved to 1000 to 1400 r.p. p. m. The resist solution is rotated at high speed to spread the resist solution throughout the substrate to form a thin film of the resist solution, which is dried and then conveyed to an edge remover, where the resist at the peripheral portion is peeled and removed. .
[0003]
FIG. 15 is a plan view showing a schematic configuration of a typical coating processing unit. As shown in FIG. 15, a coater cup 110 and an edge remover 120 are arranged adjacent to each other in the coating processing unit 100, and a transfer arm mechanism is arranged from the coater cup 110 to the edge remover 120. The transfer of the substrate between the coater cup 110 and the edge remover 120 is performed by the transfer arm 130. The substrate G coated with the resist in the coater cup 110 is scooped up by the transport arm 130, transported to the edge remover 120, set on the edge remover 120, and stripped of the resist on the peripheral edge.
[0004]
The resist solution dropped onto the substrate G in the coater cup 110 is a solution obtained by dissolving a resist agent in a solvent, and PGMEA (polyethylene glycol methyl acetate) or EL (ethyl lactate) is used as a solvent for resist coating of LCDs. ) And the like.
[0005]
[Problems to be solved by the invention]
However, since the resist solution using EL (ethyl lactate) as a solvent has poor drying properties and takes a long time to dry, a so-called “raw dry” state is obtained even after a thinning process is performed by high-speed rotation in the coater cup 110. And the surface of the resist film is still in a soft state.
[0006]
Therefore, when the substrate G is transferred from the coater cup 110 to the edge remover 120 from the coater cup 110 to the edge remover 120, when the lower surface of the substrate G contacts the spin chuck or the transfer arm 130, traces of contact with the resist film on the lower surface of the substrate G are observed. It may remain as a transfer mark. When this transfer mark is formed, the thickness of a resist film formed as a result of a series of processes such as subsequent exposure and development processes fluctuates, causing a problem of lowering LCD quality and lowering the yield. .
[0007]
The present invention has been made to solve the above problems. That is, an object of the present invention is to provide a coating method and a coating apparatus capable of forming a resist film having a uniform thickness.
[0008]
[Means for Solving the Problems]
In order to solve the above problem, a coating method according to claim 1 includes a step of dropping a coating liquid onto a substrate to be processed held by a holding unit in a processing container; Rotating at a speed of 1;Detecting the value of the solvent vapor pressure in the processing container, if the detected value is higher than a predetermined upper limit,Open the lid of the processing containerAnd let outside air flow into the processing vessel,Rotating the holding means at a second speed for a predetermined time;By touching the coating film on the substrate to be treated to the outside air flowing into the processing container, the drying of the coating film is promoted.ProcessA step of detecting the value of the solvent vapor pressure in the processing container, and ending the step of promoting the drying when the detected value falls within an allowable range,Is provided.
[0010]
Claim2A coating method, a step of dropping a coating liquid onto a substrate to be processed held by a holding unit in a processing container, and a step of rotating the holding unit at a first speed in a state where the processing container is sealed,Detecting the value of the solvent vapor pressure in the processing container, if the detected value is higher than a predetermined upper limit,The sealed processing containerWhile applying a negative pressure to the inside to suck in the air inside and simultaneously supply an inert gas into the processing vessel to replace the inside of the processing vessel with an atmosphere containing no solvent vapor,Rotating the holding means at a second speed for a predetermined time;Thereby, the drying of the coating film on the substrate to be processed is promoted.Process andA step of detecting the value of the solvent vapor pressure in the processing container, and ending the step of promoting the drying when the detected value falls within an allowable range,It is characterized by having.
[0012]
Claim3The method of applying, a step of dropping a coating liquid on the substrate to be processed held by the holding means in the processing container, and the processing containerWith lidRotating the holding means at a first speed in a sealed state;Supplying gas into the processing container from an opening disposed obliquely to the radial direction of the processing container, and evacuating from a gas suction port disposed near the center on the lower surface side of the lid. By rotating the holding means at a second speed while spirally flowing gas in the upper space of the substrate to be processed in the closed processing container,Is provided.
[0013]
Claim4The method of applying, a step of dropping a coating liquid on the substrate to be processed held by the holding means in the processing container, and the processing containerWith lidRotating the holding means at a first speed in a sealed state;Detecting the value of the solvent vapor pressure in the processing container, and if the detected value is higher than a predetermined upper limit, disposing it in the processing container obliquely to the radial direction of the processing container. The gas is supplied from the opened opening, and is evacuated from the gas suction port disposed near the center on the lower surface side of the lid, so that the gas is swirled into the upper space of the substrate to be processed in the closed processing container. Rotating the holding means at a second speed while flowing water, and promoting the drying of the coating film on the substrate to be processed; and detecting the value of the solvent vapor pressure in the processing container and detecting the detected value. Terminating the step of accelerating the drying when it is within the allowable range,Is provided.
[0014]
Claim5The application method of5. The coating method according to claim 4, wherein the holding unit is rotated at the second speed in a direction opposite to a flow direction of the spiral gas. 6.I do.
[0015]
Claim6The application method ofThe coating method according to any one of claims 1 to 5, wherein the second speed is 50 to 100 r. p. m, and the rotation time is 5 to 10 seconds.I do.
[0016]
Claim7A coating container that rotatably stores the substrate to be processed, a lid that seals the processing container, a unit that rotates the substrate to be processed in the processing container, and a process on the upper surface of the substrate to be processed. Means for supplying an agent, and means for generating a vortex air flow in the space between the upper surface of the substrate to be processed and the lid,The means for generating a vortex-like air flow includes a gas outflow nozzle disposed in the processing container obliquely to a radial direction of the processing container, and a gas outflow nozzle disposed near a center on a lower surface side of the lid. A gas suction port provided, a gas supply system for supplying gas to the gas outflow nozzle, and a suction system for applying a negative pressure to the gas suction port.Is provided.
[0017]
Claim8The coating device is8. The coating apparatus according to claim 7, wherein a solvent sensor for detecting a solvent vapor pressure in the processing container, and the gas from the gas outlet nozzle until the value of the detected solvent vapor pressure is within an allowable range. Control means for controlling the gas supply system and the suction system so as to suck the gas from the gas suction port and promote drying of the coating film on the substrate to be processed,Is provided.
[0018]
Claim9The coating device isA processing container that rotatably stores the substrate to be processed, a lid that seals the processing container, a holding unit that rotates the substrate to be processed in the processing container, and a processing agent that supplies a processing agent to the upper surface of the substrate to be processed. Means, a gas outflow nozzle provided in the processing vessel, a gas supply system for supplying gas to the gas outflow nozzle, a gas suction port provided in the lid, and a negative pressure applied to the gas suction port. A suction system to be actuated, a solvent sensor for detecting a solvent vapor pressure in the processing solution, and when a value detected by the solvent sensor is higher than a predetermined upper limit value, the inside of the processing container sealed with the lid. At the same time as applying a negative pressure to suck the air inside, the inert gas is supplied into the processing vessel to replace the internal space of the processing vessel with an atmosphere containing no solvent vapor, and the holding means is moved at a predetermined speed. Rotate for a predetermined time This promotes drying of the coating film on the substrate to be processed, and stops the operations of the gas supply system, the suction system, and the holding unit when the value detected by the solvent sensor falls within an allowable range. Control means for controllingI do.
[0021]
Claim 10Is a processing container that rotatably stores a substrate to be processed, a lid that seals the processing container, an opening / closing unit that opens and closes the lid, and a rotating unit that rotates the substrate to be processed in the processing container. Means for supplying a processing agent to the upper surface of the substrate to be processed; andPaint filmMeans for detecting the dry state of thePaint filmMeans for controlling the opening / closing means and the rotating means based on the dry state ofA coating device having a means for detecting a dry state of the coating film on the substrate to be processed, wherein the means for detecting the dry state of the coating film by measuring the weight of the substrate to be processed or the refractive index of the coating film Is characterized byI do.
[0022]
Claim 11Is a processing container that rotatably stores a substrate to be processed, a lid that seals the processing container, an opening / closing unit that opens and closes the lid, and a rotating unit that rotates the substrate to be processed in the processing container. Means for supplying a processing agent to the upper surface of the substrate to be processed, a solvent sensor for detecting a solvent vapor pressure in the processing vessel, and the detected solvent vapor pressureThe cover is opened until the value falls within the allowable range, the outside air having a low solvent vapor pressure flows into the processing container, the rotating means is rotated, and the outside air having the coating film on the substrate to be processed flows thereinto. , So as to accelerate the drying of the coating film,Said opening and closing meansSaidMeans for controlling the rotating means.You.
[0023]
The present inventionThenHolding meansAfter dropping the coating liquid on the substrate to be processed held above,Processing containerSealedHolding meansIs rotated at a first speed to form a thin film of the coating liquid on the substrate to be processed,Processing containerOpen the lidHolding meansAt a second speed.
[0024]
As a result, a gas stream having a low solvent concentration is formed in the space just above the coating liquid thin film on the substrate to be processed, so that drying of the coating liquid is promoted and drying is performed to such an extent that transfer marks are not formed. This prevents a film thickness defect due to the formation of.
[0025]
In the present invention,The second speed, 50-100 r. p. m, rotation timeToBy setting it to 5 to 10 seconds,An airflow having an appropriate flow rate is formed in the upper space of the substrate on which the thin film coating is formed, and the airflow is dried to such an extent that transfer marks are not formed.
[0026]
In addition, the present inventionThenHolding meansAfter dropping the coating liquid on the substrate to be processed held above,Processing containerSealedHolding meansWas rotated at a first speed to form a thin film of the coating liquid on the substrate to be processed, and then the above-mentioned closedProcessing containerWhile replacing the inside with an inert gas,Holding meansIs rotated at a second speed for a predetermined time.
[0027]
for that reasonProcessing containerThe solvent vapor pressure in the inside decreases and the solvent in the coating film evaporates easily, so the coating film is easy to dry and is dried to the extent that transfer marks are not formed, preventing poor film thickness due to transfer mark formation Is done.
[0029]
In addition, the present inventionThenHolding meansAfter dropping the coating liquid on the substrate to be processed held above,Processing containerSealedHolding meansWas rotated at a first speed to form a thin film of the coating liquid on the substrate to be processed, and then the above-mentioned closedProcessing containerA gas is caused to flow in the upper space of the substrate to be processed in the inside to form a spiral airflowAt the same time, the holding means rotates at the second speed. The rotation at the second speed is performed, for example, in a direction opposite to the flow direction of the spiral gas.
[0030]
As a result, a gas stream having a low solvent concentration is formed in a space immediately above the thin film of the coating liquid on the substrate to be processed, so that the drying of the coating liquid is promoted, and the coating liquid is dried to the extent that transfer marks are not formed. Defective film thickness due to the formation of traces is prevented.
[0045]
In addition, the present inventionThenDetects the solvent vapor pressure in the processing vessel and controls opening and closing of the lid of the processing vessel, rotation of the holding means, replacement of the atmosphere in the processing vessel with an inert gas, formation of an airflow in the processing vessel, etc. based on the solvent vapor pressure By doing, the inside of the processing vesselIt can be in an ideal state. for that reasonPaint filmIs promoted and dried to such an extent that transfer marks are not formed, so that a film thickness defect due to the formation of transfer marks is prevented.
[0046]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0047]
(1st Embodiment)
FIG. 1 is a perspective view of a coating and developing apparatus according to an embodiment of the present invention, and FIG. 2 is a plan view thereof.
[0048]
The coating / developing apparatus 1 includes a cassette station C / S on one end side.
[0049]
On the other end side of the coating / developing device 1, an LCD glass substrate G (hereinafter, the LCD glass substrate is abbreviated as “substrate”) is transferred to and from an exposure device (not shown). Interface unit I / F is arranged.
[0050]
In the cassette station C / S, a plurality of, for example, four sets of cassettes 2 containing substrates G such as LCD substrates are mounted. On the front side of the cassette 2 of the cassette station C / S, an auxiliary arm 4 for carrying and positioning the substrate G, which is a substrate to be processed, and holding and transferring the substrate G to and from the main arm 3. Is provided.
[0051]
The interface unit I / F is provided with an auxiliary arm 5 for transferring the substrate G to and from an exposure apparatus (not shown). In the interface unit I / F, an extension unit 6 for transferring the substrate G to and from the main arm 3 and a buffer unit 7 for temporarily suspending the substrate G are arranged.
[0052]
Two main arms 3 are arranged in series so that the central part of the coating / developing apparatus 1 can move in the longitudinal direction, and the first processing unit group A, A second processing unit group B is arranged. Between the first processing unit group A and the second processing unit group B, a relay section 8 for temporarily holding and cooling the substrate G is arranged.
[0053]
In the first processing unit group A, a cleaning processing unit SCR for cleaning the substrate G and a developing processing unit DEV for performing a developing process are provided side by side on the cassette station C / S. Further, on the opposite side of the cleaning processing unit SCR and the developing processing unit DEV across the transport path of the main arm 3, two sets of heat treatment units HP arranged vertically in two stages and a UV processing unit arranged vertically in two stages are provided. The unit UV and the cooling unit COL are arranged adjacent to each other.
[0054]
In the second processing unit group B, a coating unit COT that performs a resist coating process and an edge remove process is arranged. An adhesion unit AD and a cooling unit COL for hydrophobically embedding two vertically arranged substrates G are provided on the opposite side of the coating processing unit COT with the conveyance path of the main arm 3 therebetween. The arranged heat treatment units HP and cooling units COL and two sets of heat treatment units HP vertically arranged in two stages are arranged adjacent to each other. When the heat treatment unit HP and the cooling unit COL are arranged vertically in two stages, the heat treatment unit HP is arranged above and the cooling unit COL is arranged below, thereby avoiding mutual thermal interference. This allows more accurate temperature control.
[0055]
The main arm 3 includes an X-axis driving mechanism, a Y-axis driving mechanism, and a Z-axis driving mechanism, and further includes a rotation driving mechanism that rotates about the Z-axis. The main arm 3 appropriately travels along the central passage of the coating / developing apparatus 1 and transports the base slope G between the processing units. Then, the main arm 3 loads the unprocessed substrate G into each processing unit, and unloads the processed substrate G from each processing unit.
[0056]
In the coating / developing apparatus 1 of the present embodiment, by integrating and integrating the respective processing units as described above, it is possible to achieve space saving and more efficient processing.
[0057]
In the coating / developing apparatus 1 configured as described above, first, the substrate G in the cassette 2 is transferred to the cleaning processing unit SCR via the auxiliary arm 4 and the main arm 3 and subjected to cleaning processing.
[0058]
Next, it is conveyed to the adhesion unit AD via the main arm 3, the relay section 8, and the main arm 3, and is subjected to a hydrophobic treatment. Thereby, the fixability of the resist is improved.
[0059]
Next, it is conveyed to the cooling unit COL via the main arm 3 and cooled. Thereafter, the resist is transferred to the coating unit COT via the main arm 3 and coated with the resist.
[0060]
Next, the substrate G is conveyed to the heat processing unit HP via the main arm 3 and subjected to a pre-baking process. Then, after being conveyed to the cooling unit COL via the main arm 3 and cooled, it is conveyed to the exposure device via the main arm 3 and the interface unit I / F, where a predetermined pattern is exposed.
[0061]
Then, the substrate G that has been exposed again is carried into the apparatus 1 via the interface unit I / F, conveyed to the heating processing unit HP via the main arm 3, and subjected to post-exposure bake processing.
[0062]
Thereafter, the substrate G is carried into the cooling unit COL via the main arm 3, the relay section 8, and the main arm 3, and is cooled. Then, the substrate G is carried into the development processing unit DEV via the main arm 3 and subjected to development processing, and a predetermined circuit pattern is formed. The developed substrate G is carried into the post-bake processing unit HP via the main arm 3 and subjected to post-bake processing.
[0063]
Then, the substrate G subjected to the post-baking process is accommodated in a predetermined cassette 2 on the cassette station C / S via the main arm 3 and the auxiliary arm 4.
[0064]
Next, the coating processing unit (COT) according to the present embodiment will be described. FIG. 3 is a plan view of the coating unit (COT) according to the present embodiment, FIG. 4 is a vertical sectional view, and FIG. 5 is a perspective view.
[0065]
As shown in FIG. 3, a coater cup 20 as a resist coating device and an edge remover 60 are arranged adjacent to each other in the coating processing unit (COT). Among these, the coater cup 20 is a device for applying a processing agent such as a resist solution to the surface of the substrate G that has been subjected to a pre-treatment such as a cleaning process or pre-baking, and the edge remover 60 is a device for coating the surface with the coater cup 20. This is an apparatus that peels off and removes a resist coating film on an outer peripheral portion (edge) of the substrate G on which a coating film is formed, which does not require resist coating.
[0066]
A transfer device is provided between the coater cup 20 and the edge remover 60, and a transfer arm 62 that moves on rails 61 of the transfer device transfers the substrate G between the coater cup 20 and the edge remover 60. Transport mechanism.
[0067]
Next, the periphery of the coater cup 20 will be described.
[0068]
FIG. 6 is a plan view showing a state where the lid 22 of the coating unit (COT) according to the present embodiment is opened. In FIG. 6, the lid 22 and a part of the lid lifting / lowering mechanism are omitted for convenience of explanation and illustration.
[0069]
A spin chuck 23 for rotatably holding the substrate G and a rotation driving mechanism for rotating the spin chuck 23 are provided in a space inside the coater cup 20. A resist nozzle 57 for accessing the inside of the coater cup 20 and discharging a resist solution onto the substrate G set on the spin chuck 23 is provided at a position near the coater cup 20.
[0070]
A disc-shaped rotating cup CP is disposed inside the coater cup body 21, and a spin chuck 23 is disposed inside the rotating cup CP. The spin chuck 23 is configured to rotate by the rotational driving force of the drive motor 25 while the substrate G is fixedly held by vacuum suction.
[0071]
The drive motor 25 transmits a rotational driving force to a rotating shaft 27 via a gear train 26. Further, the rotating shaft 27 is moved vertically by a lifting drive means 28 along a lifting guide means 32 in the drawing. Mounted movably.
[0072]
At the time of resist application, as shown in FIG. 4, the spin chuck 23 is lowered to a position lower than the upper end of the rotating cup CP. On the other hand, when the substrate G is transferred between the spin chuck 23 and the main arm 4 when the substrate G is taken in and out of the coater cup 20, the elevating drive unit 28 moves the rotating shaft 27 and the spin chuck 23 upward. And the spin chuck 23 is displaced to a position higher than the upper end of the rotating cup CP.
[0073]
A resist nozzle 57 for discharging a resist solution onto the substrate G is attached to a turning mechanism 56 via a resist nozzle scan arm 55, and turns around a fulcrum 56a in a horizontal plane and near the center of the coater cup body 21. You can access up to.
[0074]
A resist pipe (not shown) is attached to the resist nozzle 57, and a resist liquid is supplied to the resist nozzle 57 from the resist liquid supply mechanism (not shown) via the resist pipe.
[0075]
In the coater cup 20, an upper opening of a coater cup body 21 that performs a coating process on the substrate G is covered with a lid 22, and the lid 22 is held by a holding member 41.
[0076]
As shown in FIGS. 3 and 4, the holding member 41 is provided between two arms 41 a, 41 a for holding the lid 22 at the tip thereof, and between the two arms 41 a, 41 a. It is composed of connecting members 41b, 41b for connecting the arms 41a, 41a. The base side of the holding member 41, that is, the side opposite to the side that holds the lid 22, extends into the cup lifter 42, and the lid 22 is moved in the vertical direction by a lid lifting / lowering mechanism 40 disposed inside the cup lifter 42 described later. It has become.
[0077]
The cup lifter 42 is provided at a position opposite to the edge remover 60 with respect to the coating apparatus main body 21.
[0078]
As shown in FIG. 3, the front surface of the cup lifter 42, that is, the surface facing the coater cup body 21, is provided with grooves 42a, 42a extending in parallel with each other in the vertical direction, and is held through these grooves 42a, 42a. The base side portion of the member 41 extends from the front side of the cup lifter 42 to the inside of the cup lifter 42.
[0079]
As shown in FIGS. 3 and 5, linear projections 41 c, 41 c extending in the vertical direction in the figure are provided at the base of the holding member 41 on the outside of each of the two arms 41 a, 41 a of the holding member 41. The projections 41c are movably engaged with guide rails 43 vertically arranged on the inner surface of the side housings 42 of the arm lifter 42, respectively. Thus, the holding member 41 can move up and down in the vertical direction along the guide rails 43.
[0080]
As shown in FIG. 4, a cylinder 44 for vertically moving the holding member 41 in the vertical direction is disposed below the holding member 41. The cylinder 44 is mounted so as to penetrate the bottom plate 24, and nearly half of the lower side of the cylinder 44 projects below the bottom plate 24.
[0081]
A rod 45 enters and exits from the upper part of the cylinder 44, and the upper part of the rod 45 is fixed to the holding member 41. On the other hand, the lower part of the rod 45 is fixed to a piston (not shown) which moves up and down by the pressure of air in the cylinder 44.
[0082]
Next, a control system of the coating processing unit (COT) according to the present embodiment will be described. FIG. 7 is a block diagram showing a control system of the coating processing unit (COT) according to the present embodiment.
[0083]
As shown in FIG. 7, in the coating processing unit (COT) according to the present embodiment, a rotation drive mechanism M for rotating the substrate G, a lid elevating mechanism 40 for elevating and lowering the lid of the coater cup 20, and a set in the coater cup 20. A processing agent supply mechanism 70 that supplies a solvent, a resist solution, and the like to the substrate G thus obtained is connected to the control unit 200, and the control unit 200 controls the entire system.
[0084]
Next, the operation of the thus configured LCD glass substrate coating / developing apparatus will be described.
[0085]
FIG. 8 is a flowchart of a coating process performed by the coating processing unit (COT) according to the present embodiment.
[0086]
After the cassette 2 accommodating the substrate G is placed in the cassette station 3 of the coating / developing apparatus of the present embodiment, the power is turned on to start up the coating / developing apparatus. The substrate G stored in the main arm 4 is taken out and delivered to the main arm 4. The main arm 4 that has received the substrate G moves on the rail and is in a processing unit that performs processing before resist application, such as a brush scrubber, a high-pressure jet cleaning unit SCR, a heating unit HP, an adhesion unit AD, and a cooling unit COL. And perform necessary processing. When a series of necessary processing is completed, the substrate G is taken out of the processing unit, moved on the rail, and accesses the coater cup 20 of the coating processing unit (COT).
[0087]
In the coater cup 20, the lid 22 is lifted in synchronization with the movement of the main arm 4, and the upper part of the coater cup body 21 is opened. The main arm 4 on which the substrate G is placed enters between the released upper portion of the coater cup main body 21 and the lifted lid 22, and transfers the substrate G to the upper surface of the spin chuck 23 exposed at the upper portion of the coater cup main body 21. Upon receiving the substrate G, the spin chuck 23 holds the substrate G by applying a negative pressure to a suction opening (not shown) provided at the center of the upper surface thereof, and moves vertically downward in this state. The substrate G is pulled into the coater cup body 21 and the setting of the substrate G is completed (step 1).
[0088]
When the setting of the substrate G on the coater cup 20 is completed, the turning mechanism 56 operates to move the resist nozzle scan arm 55, and the resist nozzle 57 is moved to a position substantially at the center of the substrate G held on the spin chuck 23. It is.
[0089]
The resist nozzle 57 is provided with a thinner nozzle (not shown) for dropping a solvent. Prior to the dropping of the resist, the thinner nozzle wets the upper surface of the substrate G by dropping a solvent (pre-wet), and promotes diffusion of the resist dropped thereafter.
[0090]
In this state, the substrate G is first rotated (step 2).
[0091]
Next, a solvent is dropped and diffused on the rotating substrate G to wet the entire surface of the substrate G with the solvent (pre-wet) (step 3).
[0092]
When the pre-wet is completed, a predetermined amount of resist is dropped from the resist nozzle 57 (step 4).
[0093]
Next, the lid 22 is lowered to cover the upper portion of the coater cup main body 21 to seal the inside of the coater cup main body 21 (step 5).
[0094]
Next, the spin chuck 23 is rotated at a high speed for a predetermined time, and the resist that has just been dropped is diffused throughout the substrate G, and excess resist is shaken off to form a thin resist solution film on the substrate G (step 6). In this embodiment, 1300 r. p. m. For 15 seconds.
[0095]
In this state, since the space inside the coater cup main body 21 is filled with the solvent vapor, the resist solution of the substrate G is not easily dried, and the upper surface of the substrate G is in a wet state.
[0096]
Next, the lid 22 is raised to open the upper portion of the coater cup main body 21 (step 7).
[0097]
Next, in this state, the spin chuck 23 is rotated again to promote the drying of the thin film of the resist solution on the substrate G (Step 8). The rotation speed at this time is suppressed to a low rotation as compared with the rotation immediately after the resist dropping. For example, 100r. p. m. Rotate for 5 seconds.
[0098]
The rotation speed at this time is 50 to 100 r. p. m. Is preferred. The reason for setting the range of the rotation speed in this way is that if the rotation speed exceeds the upper limit value, there occurs a problem that the coating becomes uneven at the corners of the substrate G, that is, the film thickness becomes abnormally large.
[0099]
On the other hand, if the rotation speed is lower than the lower limit, the drying is not promoted, and the effect of preventing the transfer cannot be obtained.
[0100]
The rotation speed and the rotation time are determined according to the type of the resist and the solvent used. Further, the time for rotating at the low rotation speed is determined according to the rotation speed. For example, 50 rotations rotate for 7 to 10 seconds, 80 rotations rotate for 5 to 7 seconds, and 100 rotations rotate for 3 to 5 seconds.
[0101]
The reason for setting the range of the rotation time is that if the rotation time exceeds the upper limit, there is a problem that coating unevenness at the corners of the substrate G, that is, an abnormally large film thickness occurs.
[0102]
On the other hand, if the rotation time is less than the lower limit, the drying is not promoted, and the effect of preventing the transfer cannot be obtained.
[0103]
By rotating at a low speed with the lid 22 opened, a weak airflow is generated in the upper space of the substrate G. Due to the opening of the lid 22 and the formation of this weak airflow, the air filled with the solvent vapor in the upper space of the substrate G is replaced with the air outside the coater cup body 21. Since this outside air contains almost no solvent vapor, when this outside air flows into the upper space of the substrate G in the coater cup body 21, the thin film of the resist solution formed on the substrate G almost completely removes the solvent vapor. The thin film is exposed to outside air that does not contain the solvent, and the solvent in the thin film is easily volatilized, thereby promoting the drying of the resist thin film.
[0104]
The degree of drying here is a state in which the transfer marks are dried to such an extent that no transfer marks remain on the contact portions even when they are set on the spin chuck 23 or the edge remover 60.
[0105]
Next, after the rotation is stopped, the substrate G is taken out of the coater cup 20 (step 9), and the substrate G is transported to a subsequent processing device such as an edge remove process. As described above, according to the coating method according to the present embodiment, the resist solution is dropped on the substrate G, and the substrate G is rotated at a high speed while the coater cup 20 is closed to diffuse the resist film over the entire substrate G to form a resist film. After thinning, the lid 22 of the coater cup 20 is once opened to take in outside air. In this state, the substrate G is rotated at a relatively low speed to accelerate the drying of the resist film. Since drying at this time is performed appropriately, no transfer mark remains on the contact portion between the spin chuck 23 or the edge remover 60 and the lower surface of the substrate G. Therefore, even after a subsequent processing step, a failure in the thickness of the resist film is prevented.
[0106]
Note that the present invention is not limited to this embodiment.
[0107]
For example, in the above embodiment, an apparatus for applying a resist to an LCD glass substrate has been described as an example, but it goes without saying that an apparatus for applying a resist to a silicon wafer can be similarly applied.
[0108]
(Second embodiment)
Hereinafter, a second embodiment according to the present invention will be described. The description of the same parts as those in the first embodiment will be omitted.
[0109]
In the coating processing unit (COT) according to the present embodiment, after a resist solution is dropped on the substrate G, the resist solution is rotated at a high speed to form a thin film of the resist solution on the substrate G, and instead of rotating the substrate G at a low speed, a coater is used. By replacing the inside of the cup 20 with nitrogen gas, drying of the resist solution thin film on the upper surface of the substrate G is promoted.
[0110]
That is, the resist solution is dropped on the substrate G held on the spin chuck 23, and is rotated at a high speed to diffuse the resist solution over the entire upper surface of the substrate G. Form a thin film of the solution.
[0111]
Next, while maintaining the hermetically closed state with the lid 22 of the coater cup 20 closed, a negative pressure is applied to the inside of the coater cup 20 to suck air therein, and at the same time, nitrogen gas is supplied from the nitrogen gas supply system to the coater cup 20. It is supplied to the inside to replace the inner space of the coater cup 20 with nitrogen gas.
[0112]
By doing so, the air in the coater cup 20 filled with the solvent vapor in the coater cup 20 is removed and replaced with nitrogen gas containing no solvent vapor. Therefore, the atmosphere in the coater cup 20 is replaced with a dry atmosphere containing no solvent vapor. Since the resist solution thin film on the substrate G touches the dried nitrogen gas, the solvent is easily evaporated, and the drying of the resist solution thin film is promoted.
[0113]
In the present embodiment, the atmosphere in the coater cup 20 is replaced with nitrogen while the lid 22 of the coater cup 20 is kept closed, so that the solvent vapor does not leak out of the coater cup 20, and therefore, the atmosphere around the coating unit is not changed. Is not contaminated by the solvent.
[0114]
Note that in the second embodiment, the nitrogen replacement is performed while the substrate G is stationary, but the nitrogen replacement may be performed while rotating the substrate G.
[0115]
Also, instead of performing this nitrogen substitution. The drying of the resist solvent thin film on the upper surface of the substrate G may be promoted by applying a negative pressure to the inner space of the coater cup 20.
[0116]
Further, in this case, the drying can be further promoted by rotating the substrate G at the same time as applying the negative pressure.
[0117]
(Third embodiment)
Hereinafter, a third embodiment according to the present invention will be described. The description of the same parts as those of the first and second embodiments will be omitted.
[0118]
In the coating processing unit (COT) according to the present embodiment, after the resist solution is dropped on the substrate G, the resist solution is rotated at a high speed to form a thin film of the resist solution on the substrate G, and then the substrate G is rotated at a low speed. A spiral airflow is formed on G, and this airflow promotes drying of the resist solution thin film on substrate G.
[0119]
FIG. 9 is a partially enlarged view of a vertical sectional view of the coating unit (COT) according to the present embodiment, and FIG. 10 is a plan view of the coating unit (COT) with the lid 22 opened. FIG.
[0120]
As shown in FIGS. 9 and 10, four gas ducts 30 to 33 for flowing gas inside the coater cup main body 21 according to the present embodiment have the same circle around the center of the coater cup main body 21. They are arranged at symmetrical positions on the circumference. The lower portions of these gas ducts 30 to 33 are connected to a gas supply system (not shown), and air or an inert gas such as nitrogen or argon is supplied from the gas supply system.
[0121]
Openings 34 to 37 are provided on the inner side surface of the coater cup body 21 in a direction oblique to the radial direction of the coater cup body 21, and these openings 34 to 37 are respectively provided with the gas ducts 30 to 33. Connected to the top of the An opening (not shown) is provided over the entire side surface of the rotating cup CP, and faces the openings 34 to 37.
[0122]
Therefore, the gas flowing out from the gas ducts 30 to 33 flows into the inner space of the coater cup main body 21 through the openings 34 to 37 and the opening on the side surface of the rotating cup CP. At this time, since the opening is directed obliquely to the radial direction of the coater cup main body 21, the gas flows obliquely from the circumferential direction of the inner circumferential circle of the coater cup main body 21 as shown by the arrow in FIG.
[0123]
On the other hand, as shown in FIG. 9, a through hole 22a is provided in the center of the lid 22, and a vacuum system is connected to the through hole 22a. Therefore, by operating this vacuum system, a vacuum acts on the through-hole 22a.
[0124]
FIG. 11 is a block diagram showing a control system of the coating processing unit (COT) according to the present embodiment.
[0125]
As shown in FIG. 11, in the coating processing unit (COT) according to the present embodiment, a rotation driving mechanism M for rotating the substrate G and a lid lifting mechanism for lifting and lowering the lid 22.40, Treatment agent supply system70, A gas supply system 180 and a vacuum supply system 190200Connected to this control unit200It is controlled in a unified manner.
[0126]
Next, a coating process performed by the coating processing unit (COT) according to the present embodiment will be described. FIG. 12 is a flowchart of a coating process performed by the coating processing unit (COT) according to the present embodiment.
[0127]
In this coating processing unit (COT), the substrate G is set (Step 1), the surface of the substrate G is pre-wet with a solvent (Steps 2 to 3), a resist is dropped (Step 4), and the substrate G is sealed. Is rotated at a high speed (step 6), and the gas supply system 180 and the vacuum supply system 190 are operated to form a vortex in the upper space of the substrate G of the coating apparatus.
[0128]
The airflow is shown by arrows in FIGS. 9 and 10.
[0129]
As described above, while the gas flows obliquely into the space inside the coater cup main body 21 from the openings 34 to 37 on the inner side surface, the gas is evacuated through the through hole 22 a at the center of the lid 22. As shown, a spiral airflow is formed in the upper space of the substrate G. This airflow promotes drying of the resist solution thin film formed on the upper surface of the substrate G. Since the drying at this time is performed appropriately, no transfer mark remains on the contact portion between the spin chuck 23 or the edge remover 60 and the lower surface of the substrate G. Therefore, even after a subsequent processing step, a failure in the thickness of the resist film is prevented.
[0130]
In addition, as a direction in which gas flows to form a spiral airflow, there are two methods, a method of flowing gas in the same direction as the rotation direction of the substrate G and a method of flowing gas in the direction opposite to the rotation direction of the substrate G. There is a method.
[0131]
(Fourth embodiment)
Hereinafter, a fourth embodiment according to the present invention will be described. The description of the same parts as those in the first to third embodiments will be omitted.
[0132]
In the coating unit (COT) according to the present embodiment, a solvent vapor pressure sensor (hereinafter, “solvent vapor pressure sensor” is simply abbreviated as “solvent sensor”) for detecting a solvent vapor pressure is provided inside the coater cup 20. Based on the solvent vapor pressure in the coater cup CP detected by the solvent sensor, the time for opening the lid 22 to promote drying, the rotation speed when rotating the substrate G with the lid 22 opened, and the like are set. Control.
[0133]
FIG. 13 is a block diagram showing a control system of the coating processing unit (COT) according to the present embodiment.
[0134]
As shown in FIG. 13, in the coating processing unit (COT) according to the present embodiment, a rotation driving mechanism M for rotating the substrate G and a lid lifting mechanism for lifting and lowering the lid 22.40, Treatment agent supply system70, And the solvent sensor S are connected to the control unit 200, and are controlled by the control unit 200.
[0135]
Next, a coating process performed by the coating processing unit (COT) according to the present embodiment will be described. FIG. 14 is a flowchart of a coating process performed by the coating processing unit (COT) according to the present embodiment.
[0136]
In the coating processing unit (COT), the substrate G is set (Step 1), the surface of the substrate G is pre-wet with a solvent (Steps 2 to 3), a resist is dropped (Step 4), and the substrate G is sealed. After the high-speed rotation (step 6), the solvent vapor pressure in the coater cup CP is detected by the solvent sensor S (step 7).
[0137]
Next, it is determined whether or not the detected solvent vapor pressure in the coater cup CP is an appropriate value (step 8).
[0138]
If the detected solvent vapor pressure is an appropriate value, that is, if the detected solvent vapor pressure is lower than the upper limit obtained in advance, it is determined that the coating film on the substrate G has been dried to some extent, and the coating process is terminated (step 11). ).
[0139]
On the other hand, if the detected value of the solvent vapor pressure is not an appropriate value, that is, if the detected solvent vapor pressure is higher than the upper limit obtained in advance, it is determined that the coating film on the substrate G is insufficiently dried, and the drying is accelerated. That is, the lid 22 is lifted up and released (step 9), and outside air having a low solvent vapor pressure is caused to flow into the coater cup CP. Then, the spin chuck 23 is rotated at a low speed for a predetermined time, and the coating film on the substrate G is brought into contact with the relatively dry outside air to accelerate the drying (step 10).
[0140]
After the low-speed rotation for a predetermined time, the solvent vapor pressure in the coater cup CP is detected in the same manner as described above (step 7), and it is determined whether or not the detected solvent vapor pressure is within an allowable range (step 8).
[0141]
This loop of Steps 7 to 10 is continued until the solvent vapor pressure detected by the solvent sensor S falls within the allowable range. When the solvent vapor pressure finally falls within the allowable range, a series of drying promotion is performed. Is completed (step 11).
[0142]
As described above, in the coating unit (COT) according to the present embodiment, the solvent vapor pressure in the coater cup CP is constantly monitored, and the rotation is performed at a low speed with the lid 22 being opened based on the detected value of the solvent vapor pressure. Thus, the conditions of the drying promotion operation are controlled, so that a fine-grained drying promotion operation can be performed for each substrate G. Since the drying at this time is performed appropriately, no transfer mark remains on the contact portion between the spin chuck 23 or the edge remover 60 and the lower surface of the substrate G. Therefore, even after a subsequent processing step, a failure in the thickness of the resist film is prevented.
[0143]
In the present embodiment, an operation for rotating the substrate G at a low speed with the lid 22 opened is used as an operation for promoting drying. However, other than this, for example, an inactive state as in the second embodiment described above. An operation of flowing a gas or an operation of flowing an air flow from the inner side surface of the coater cup CP toward the center of the lid 22 to form a vortex air flow as in the third embodiment may be used.
[0144]
Furthermore, as a method for grasping the drying state of the coating film on the upper surface of the substrate G, in the present embodiment, a method of detecting the solvent vapor pressure in the coater cup CP is adopted. In addition, the weight of the substrate G is measured. It is also possible to use various methods, such as measuring the refractive index of the coating film.
[0145]
【The invention's effect】
As described above,ADVANTAGE OF THE INVENTION According to this invention, since drying of a coating film can be promoted and can be dried to the extent that transfer marks are not formed, it is possible to prevent the occurrence of a film thickness defect due to the formation of transfer marks..
[Brief description of the drawings]
FIG. 1 is a perspective view of an LCD glass substrate coating / developing apparatus according to an embodiment of the present invention.
FIG. 2 is a plan view of an apparatus for coating and developing an LCD glass substrate according to an embodiment of the present invention.
FIG. 3 is a plan view of a coating unit according to the embodiment of the present invention.
FIG. 4 is a vertical sectional view of a coating processing unit according to the embodiment of the present invention.
FIG. 5 is a perspective view of a coating unit according to the embodiment of the present invention.
FIG. 6 is a partially enlarged plan view of a coating unit according to the embodiment of the present invention.
FIG. 7 is a block diagram showing a control system of a coating processing unit according to the embodiment of the present invention.
FIG. 8 is a flowchart showing a coating process of a coating unit according to the embodiment of the present invention.
FIG. 9 is a partially enlarged view of a vertical section of a coating unit according to a third embodiment of the present invention.
FIG. 10 is a partially enlarged plan view of a coating processing unit according to a third embodiment of the present invention.
FIG. 11 is a block diagram showing a control system of a coating processing unit according to a third embodiment of the present invention.
FIG. 12 is a flowchart illustrating a coating process of a coating unit according to a third embodiment of the present invention.
FIG. 13 is a block diagram showing a control system of a coating processing unit according to a fourth embodiment of the present invention.
FIG. 14 is a flowchart showing a coating process of a coating unit according to a fourth embodiment of the present invention.
FIG. 15 is a vertical sectional view of a conventional coating unit.
[Explanation of symbols]
G glass substrate
20 coater cup
21 Coater cup body
22 lid
23 Spin chuck
M rotation drive mechanism
70 Treatment agent supply mechanism
30-33 Gas outlet nozzle
180 gas supply system
190 Gas suction port
22a Suction system
S solvent sensor
40 Lid lifting mechanism
200 control unit

Claims (11)

A step of dropping a coating liquid on the substrate to be processed held by the holding means in the processing container,
Rotating the holding means at a first speed with the processing vessel sealed;
Detecting the value of the solvent vapor pressure in the processing vessel, and when the detected value is higher than a predetermined upper limit , opening the processing vessel lid and allowing outside air to flow into the processing vessel, are spun at a second speed predetermined time, said by exposing a coating film on the processed substrate to the outside air that has flowed into the processing chamber, comprising the steps of Ru promotes the drying of the coating film,
A step of detecting the value of the solvent vapor pressure in the processing container, and ending the step of promoting the drying when the detected value falls within an allowable range,
A coating method, comprising: A step of dropping a coating liquid on the substrate to be processed held by the holding means in the processing container,
Rotating the holding means at a first speed with the processing vessel sealed;
A value of the solvent vapor pressure in the processing container is detected, and when the detected value is higher than a predetermined upper limit , a negative pressure is applied to the inside of the sealed processing container to suck air inside and simultaneously perform the same operation. By rotating the holding means at a second speed for a predetermined time while supplying an active gas into the processing container and replacing the inside of the processing container with an atmosphere containing no solvent vapor, the coating on the substrate to be processed is performed. Promoting the drying of the membrane ;
A step of detecting the value of the solvent vapor pressure in the processing container, and ending the step of promoting the drying when the detected value falls within an allowable range,
A coating method, comprising: A step of dropping a coating liquid on the substrate to be processed held by the holding means in the processing container,
Rotating the holding means at a first speed with the processing vessel sealed with a lid ;
Supplying gas into the processing container from an opening disposed obliquely to the radial direction of the processing container, and evacuating from a gas suction port disposed near the center on the lower surface side of the lid. By rotating the holding means at a second speed while spirally flowing gas in the upper space of the substrate to be processed in the closed processing container,
A coating method, comprising: A step of dropping a coating liquid on the substrate to be processed held by the holding means in the processing container,
Rotating the holding means at a first speed with the processing vessel sealed with a lid ;
Detecting the value of the solvent vapor pressure in the processing container, and if the detected value is higher than a predetermined upper limit, disposing it in the processing container obliquely to the radial direction of the processing container. The gas is supplied from the opened opening, and is evacuated from the gas suction port disposed near the center on the lower surface side of the lid, so that the gas is swirled into the upper space of the substrate to be processed in the closed processing container. Rotating the holding means at a second speed while flowing, the step of promoting the drying of the coating film on the substrate to be processed,
A step of detecting the value of the solvent vapor pressure in the processing container, and ending the step of promoting the drying when the detected value falls within an allowable range,
A coating method, comprising: The coating method according to claim 4, wherein the holding unit is rotated at the second speed in a direction opposite to a flow direction of the spiral gas. The second speed is between 50 and 100 r. p. m, and the rotation time is 5 to 10 seconds. A processing container that rotatably stores the substrate to be processed,
A lid for sealing the processing container,
Means for rotating the substrate to be processed in the processing container,
Means for supplying a processing agent to the upper surface of the substrate to be processed,
Means for generating a vortex air flow in the space between the upper surface of the substrate to be processed and the lid,
Has,
The means for generating the vortex air flow includes:
A gas outflow nozzle disposed in the processing container in an oblique direction with respect to a radial direction of the processing container,
A gas suction port arranged near the center on the lower surface side of the lid,
A gas supply system for supplying gas to the gas outflow nozzle,
A coating apparatus, comprising: a suction system for applying a negative pressure to the gas suction port . A solvent sensor for detecting a solvent vapor pressure in the processing container,
Until the value of the detected solvent vapor pressure falls within the allowable range, the gas is supplied from the gas outlet nozzle, the gas is sucked from the gas suction port, and drying of the coating film on the substrate to be processed is promoted. Control means for controlling the gas supply system and the suction system so that
The coating device according to claim 7, comprising: A processing container that rotatably stores the substrate to be processed,
A lid for sealing the processing container,
Holding means for rotating the substrate to be processed in the processing container,
Means for supplying a processing agent to the upper surface of the substrate to be processed,
A gas outflow nozzle disposed in the processing container,
A gas supply system for supplying gas to the gas outflow nozzle,
A gas suction port disposed on the lid,
A suction system for applying a negative pressure to the gas suction port,
A solvent sensor for detecting a solvent vapor pressure in the processing,
When the value detected by the solvent sensor is higher than a predetermined upper limit, a negative pressure is applied to the inside of the processing container sealed with the lid to suck air therein, and at the same time, an inert gas is supplied to the processing container. By rotating the holding means at a predetermined speed for a predetermined time while replacing the internal space of the processing container with an atmosphere containing no solvent vapor by supplying the inside, the drying of the coating film on the substrate to be processed is promoted, Control means for controlling so as to stop the operation of the gas supply system, the suction system and the holding means at the time when the value detected by the solvent sensor falls within the allowable range,
A coating device comprising: A processing container that rotatably stores the substrate to be processed,
A lid for sealing the processing container,
Opening and closing means for opening and closing the lid,
Rotating means for rotating the substrate to be processed in the processing container,
Means for supplying a processing agent to the upper surface of the substrate to be processed,
Means for detecting the dry state of the coating film on the substrate to be processed,
Means for controlling the opening and closing means and the rotating means based on the detected dried state of the coating film ,
A coating device having
The means for detecting the dry state of the coating film on the substrate to be processed is characterized in that the drying state of the coating film is detected by measuring the weight of the substrate to be processed or the refractive index of the coating film. apparatus. A processing container that rotatably stores the substrate to be processed,
A lid for sealing the processing container,
Opening and closing means for opening and closing the lid,
Rotating means for rotating the substrate to be processed in the processing container,
Means for supplying a processing agent to the upper surface of the substrate to be processed,
A solvent sensor for detecting a solvent vapor pressure in the processing container,
Until the value of the detected solvent vapor pressure is within the allowable range, open the lid, let the outside air having a low solvent vapor pressure flow into the processing container, rotate the rotating means, and rotate the rotating means on the substrate to be processed. exposed to the outside air flowing coating, so as to accelerate the drying of the coating film, and means for controlling said rotating means and said switching means,
A coating device comprising:

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