JP7282064B2 - Developing device and developing method - Google Patents

Description

The present invention develops substrates such as glass substrates for liquid crystal displays, semiconductor wafers, glass substrates for PDPs, glass substrates for photomasks, substrates for color filters, substrates for recording disks, substrates for solar cells, and substrates for electronic paper. The present invention relates to a developing method and a developing apparatus for developing with liquid.

2. Description of the Related Art Conventionally, substrate processing techniques for forming patterns by photolithography have been widely used in substrate manufacturing processes. The basic steps in this substrate processing technology are a film formation step, a coating step, an exposure step, a development step and an etching step. Among these processes, the developing process is a process of supplying a developer to the substrate on which the thin film and the exposed photoresist layer are laminated to develop the photoresist layer to form a mask pattern.

For example, in the developing device described in Patent Document 1, while the photoresist film is developed by uniformly supplying the developing solution to the substrate that is horizontally conveyed with the photoresist film facing upward, The in-plane uniformity of development processing is improved by locally additionally supplying the developing solution to the portions where developing ability is required.

JP 2018-120976 A

In the conventional technique described above, the developer is additionally supplied only in a partial range in the width direction perpendicular to the transport direction of the substrate. It is also considered effective to do so in the same way. The reason is as follows. As the development progresses, the photoresist material and oxygen in the air dissolve into the developer film covering the substrate, causing a phenomenon in which the developing capability of the developer is reduced. is one of the causes. Since this can occur at any position on the substrate, the uniformity of processing can be improved by supplying additional developer evenly across the width of the substrate being transported to compensate for such a decrease in developing ability. expected to improve.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and aims to further improve the in-plane uniformity of development processing by supplying additional developer in a technique for developing a photoresist film formed on a substrate surface. The purpose is to provide a technology that can

According to one aspect of the present invention, a substrate having an exposed photoresist film on its surface is supported in a horizontal position with the photoresist film facing upward and transported in the horizontal direction; a primary supply unit that supplies a developer to the upper surface of the substrate and covers the upper surface of the substrate with a liquid film of the developer; and a secondary supply unit for additionally supplying the developer onto the upper surface of the substrate. Here, the secondary supply unit includes a secondary supply nozzle having a liquid ejection port for ejecting the developer onto the upper surface of the substrate, and a liquid ejection port downstream of the primary supply unit in the transport direction. is disposed in the vicinity of the liquid ejection port on the upstream side of the liquid ejection port, regulates the thickness of the liquid film transported to a position facing the liquid ejection port, and is supplied from the liquid ejection port to the substrate. and a blocking portion that prevents the developer from flowing to the upstream side in the transport direction. Here, the blocking section has a gas injection nozzle for injecting gas from a gas ejection port arranged close to the liquid ejection port toward the liquid film on the substrate, and the gas is used to inject gas perpendicular to the transport direction. The primary supply section has a liquid discharge port for discharging the developer onto the upper surface of the substrate transported by the transport section, and the liquid in the primary supply section is The shortest distance between the ejection port and the gas ejection port is longer than the length of the substrate in the transport direction. Alternatively, the blocking portion has a blocking member extending in a width direction perpendicular to the transport direction in the vicinity of the liquid ejection port, and the lower end of the blocking member extends horizontally and is transported. The primary supply unit is opposed to the upper surface of the substrate with a gap smaller than the thickness of the liquid film formed on the substrate.

In another aspect of the present invention, there is provided a developing method for developing a photoresist film on the surface of a substrate that has been exposed to light with a developing solution, wherein the photoresist film is placed on the upper surface of the substrate supported in a horizontal position with the photoresist film facing upward. a step of primarily supplying a developer from a primary supply unit to cover the upper surface of the substrate with a liquid film of the developer; a step of horizontally conveying the substrate on which the liquid film is formed; and discharging the developer onto the upper surface of the substrate from a liquid discharge port of a secondary supply nozzle arranged above the substrate. A blocking portion disposed in the vicinity of the liquid ejection port on the upstream side of the liquid ejection port in the transport direction regulates the thickness of the liquid film transported to a position facing the liquid ejection port. At the same time, the developer supplied from the liquid ejection port to the substrate is prevented from flowing upstream in the transport direction. Here, the blocking section has a gas injection nozzle for injecting gas from a gas ejection port arranged close to the liquid ejection port toward the liquid film on the substrate, and the gas is used to eject gas perpendicular to the transport direction. The primary supply section has a liquid ejection port for ejecting the developer onto the upper surface of the substrate being transported, and the liquid ejection port of the primary supply section and the liquid ejection port are formed. The shortest distance to the gas ejection port is longer than the length of the substrate in the transport direction. Alternatively, the blocking portion has a blocking member extending in a width direction perpendicular to the transport direction in the vicinity of the liquid ejection port, and the lower end of the blocking member extends horizontally and is transported. The primary supply unit is opposed to the upper surface of the substrate with a gap smaller than the thickness of the liquid film formed on the substrate.

In the following description, the term "upstream side" simply refers to the upstream side in the transport direction of the substrate. In addition, the term "downstream side" simply refers to the downstream side in the transport direction of the substrate. When viewed from the transported substrate, its downstream end corresponds to the leading end in the transport direction. Also, the upstream end corresponds to the rear end in the transport direction.

In the invention configured as described above, the developer is additionally supplied (secondary supply) to the substrate covered with the liquid film of the developer. It is expected that this promotes development in the liquid film and improves the uniformity of processing. is not seen. In particular, the uniformity improvement effect in the direction along the conveying direction is small. It is considered that this is due to the following reasons.

When the developer is secondarily supplied to the liquid film of the developer covering the substrate, the components of the new developer are diffused into the liquid film, so that the recovery effect of the developing ability is not limited to the liquid film at the additional supply position. It is conceivable that this will also spread to the surrounding liquid film. When the secondary supply is performed while the substrate is being transported, when comparing the leading edge and the trailing edge of the substrate in the transport direction, new developer is added to the existing developer that originally formed the liquid film in the vicinity of the leading edge. It is only added, whereas near the trailing edge, more developer will be added to the existing developer already affected by the previous secondary supply. This is considered to be one of the causes of non-uniformity of processing in the transport direction, that is, the difference in processing results between the side closer to the leading edge of the substrate and the side closer to the trailing edge.

Therefore, in the present invention, a blocking portion is provided upstream of the position where the secondary supply of the developer is performed, and the thickness of the liquid film transported to the position facing the liquid ejection port is regulated, and The developer supplied to the substrate is prevented from flowing upstream in the transport direction. This suppresses the secondarily supplied developer from spreading to the upstream side, that is, to the rear end side of the substrate. Therefore, the non-uniformity of processing in the transport direction as described above is improved. In addition, since the thickness of the liquid film is reduced immediately before the developer is secondarily supplied, it is possible to suppress the ratio of the existing developer mixed into the secondarily supplied developer. This makes it possible to effectively utilize the high developing ability of the secondarily supplied developer. In this way, the blocking section has a function of blocking the flow between the liquid film formed on the substrate and the newly supplied developer.

As described above, in the present invention, when the developer is secondarily supplied to the liquid film of the developer formed on the substrate, the developer is conveyed to the position where the developer is secondarily supplied on the upstream side. This reduces the thickness of the liquid film that is formed on the surface and prevents the secondarily supplied developer from flowing out to the upstream side. With such a configuration, it is possible to further improve the in-plane uniformity of development processing.

1 is a diagram showing a first embodiment of a developing device according to the present invention; FIG. 4 is a flow chart showing an outline of development processing by the developing device; FIG. 4 is a diagram schematically showing a liquid film forming process by primary supply of a developer; FIG. 5 is a diagram for explaining processing in a second developing section; FIG. 5 is a diagram for explaining processing in a second developing section; It is a figure which illustrates the effect of the air knife in this embodiment. FIG. 10 is a diagram showing a main part of a second embodiment of a developing device according to the present invention;

<First Embodiment>
FIG. 1 is a diagram showing a first embodiment of a developing device according to the present invention. More specifically, FIG. 1(a) is a plan view showing a schematic configuration of the developing device 1 of this embodiment, and FIG. 1(b) is a side sectional view of the developing device 1. As shown in FIG. An XYZ orthogonal coordinate system is set as shown in FIG. Here, the XY plane represents the horizontal plane, and the Z direction represents the vertical direction. The (-Z) direction is the direction of gravity.

This developing device 1 performs development processing in the first development section 3, development processing in the second development section 4, and rinsing section while transporting the substrate S that has undergone the previous process inside the housing 2 in the transport direction X. This substrate processing apparatus performs a rinsing process at 5 and a drying process at a drying unit 6 in this order. As the substrate S, for example, a semiconductor substrate, a glass substrate for various applications such as a photomask, a display device, and a solar cell can be applied. This developing device 1 can be used for the purpose of developing. However, the types and uses of the substrate are not particularly limited to these.

Three partition plates 21 to 23 are provided in the middle portion of the housing 2, and these partition the interior of the housing 2 into four processing spaces. Further, a transport passage port 24 for transporting the substrate S is provided at the central portion of each of the partition plates 21 to 23 . The four processing spaces are communicated in the transport direction X by these transport passage ports 24. The first developing section 3 is disposed in the most upstream processing space, and the second most upstream processing space. A second developing section 4 is arranged in the third and fourth processing spaces, and a rinsing section 5 and a drying section 6 are arranged in the third and fourth processing spaces, respectively.

Further, in the housing 2, a carry-in port 25 for carrying in the substrate S processed by the exposure device (not shown) is provided at the upstream end in the transport direction X, while the above-described development processing, A carry-out port 26 is provided for carrying out the substrate S, which has undergone the rinsing process and the drying process, to the next processing apparatus (for example, a post-baking section for performing post-baking processing after the development process or an etching apparatus).

Further, inside the housing 2, a substrate transfer section 7 is provided for transferring the substrate S through the carry-in port 25, the transfer passage port 24, and the carry-out port 26. As shown in FIG. The substrate conveying section 7 has a plurality of conveying rollers 71 and a conveying drive mechanism 72 that drives the conveying rollers 71 . The plurality of conveying rollers 71 are arranged at predetermined intervals along the conveying route connecting the carry-in port 25, the conveying passage port 24, and the carry-out port 26, as shown in FIG. 1(b). Each transport roller 71 is composed of a rotating shaft 711 extending in a horizontal direction orthogonal to the transport direction X, that is, in the width direction Y of the substrate S, and a plurality of wheels 712 whose centers are fixed to the rotating shaft. A plurality of wheels 712 are arranged at predetermined intervals in the width direction Y with respect to the rotating shaft 711, and can support the substrate S from the lower surface side.

Each rotating shaft 711 is connected to the transport driving mechanism 72 . Then, when the drive motor (not shown) of the transport drive mechanism 72 is activated in response to an operation command from the control unit 8 that controls the entire apparatus, the rotational driving force generated by the drive motor is transmitted to the rotating shaft 711 to rotate the wheels. 712 is rotated. Therefore, as shown in FIG. 1(b), the substrate S supported vertically by the wheels 712 is positioned horizontally in the first developing section 3 with its surface (the surface on which the thin film and the resist film are laminated) facing upward. , second developing section 4 , rinsing section 5 and drying section 6 in this order.

The first developing section 3 includes slit nozzles 31 and 32 arranged above the substrate S conveyed by the conveying rollers 71 . The slit nozzle 31 has a nozzle body 311 extending in the width direction Y and a slit-shaped discharge port 312 elongated in the width direction Y on the lower surface of the nozzle body 311 . As shown in FIG. 1(a), the nozzle bodies 311 and 321 are longer than the substrate S in the width direction Y, whereas the ejection ports 311 and 312 have widths approximately equal to the width of the substrate S. . The slit nozzles 31 and 32 are arranged such that the discharge ports 312 and 322 face the upper surface of the substrate S. Of these, the slit nozzle 31 is held with its upper end inclined 45 degrees toward the (-X) direction. The reason for doing so will be described later.

The slit nozzles 31 and 32 are connected to a developer supply source 81 , and when the developer supply source 81 pressure-feeds the developer to the slit nozzles 31 and 32 in response to a discharge command from the control unit 8 , the developer is transported by the transport roller 71 . The developer is supplied to the substrate S across the width direction Y from the ejection openings 312 and 322 toward the substrate S to which the substrate S is exposed. In the first developing section 3, the substrate S passes under the slit nozzles 31 and 32, so that the entire surface of the substrate S is covered with the developer using surface tension. of liquid film is formed. Developing processing for the resist film on the substrate S is started at the time when the developer is supplied in this manner. The substrate S thus developed by the first developing section 3 is conveyed to the second developing section 4 .

The second developing section 4 includes an air nozzle 41 and a slit nozzle 42 arranged above the substrate S conveyed by the conveying rollers 71 . The slit nozzle 42 has substantially the same structure as the slit nozzle 31 . That is, the slit nozzle 42 has a nozzle body 421 extending in the width direction Y, and a slit-shaped discharge port 422 elongated in the width direction Y on the lower surface of the nozzle body 421 . The slit nozzle 42 is connected to a developer supply source 81 , and when the developer supply source 81 pressure-feeds the developer to the slit nozzle 42 in response to a discharge command from the control unit 8 , the substrate S is transported by the transport rollers 71 . , the developing solution is supplied to the substrate S across the width direction Y from the ejection port 422 toward .

At this time, a liquid film of the developer is already formed on the upper surface of the substrate S, and therefore the slit nozzle 422 has a function of additionally supplying the developer to the liquid film on the substrate S. there is In order to distinguish between these developer supplies, hereinafter, the developer supply for liquid film formation by the slit nozzles 31 and 32 will be referred to as "primary supply", and the additional developer supply by the slit nozzle 42 will be referred to as "secondary supply". shall be referred to as

From the viewpoint of reducing the environmental load, of the developer supplied to the substrate S in the first developing section 3 and the second developing section 4, the developer that has spilled from the substrate S is recovered through a recovery path (not shown), It is desirable that the developer is returned to the developer supply source 81 after being subjected to a regeneration process to remove the resist material dissolved in the liquid, dissolved oxygen, and the like and to replenish the chemical component.

An air nozzle 41 that functions as an air knife by injecting gas is arranged on the upstream side in the transport direction X, that is, adjacent to the (−X) side of the slit nozzle 42 for secondary supply. The air nozzle 41 has a nozzle body 411 extending in the width direction Y to be larger than the width of the substrate S, and a slit-shaped discharge port 412 opening toward the upper surface of the substrate S at the bottom thereof.

The air nozzle 41 is connected to an air supply source 83 via a flow rate control mechanism 84 such as a mass flow controller. When the air supply source 83 sends out a gas such as dry air in response to a control command from the control unit 8, the gas is jetted toward the substrate S from the outlet 412 of the air nozzle 41 via the flow rate control mechanism 84. . The ejection port 412 is longer than the width of the substrate S along the width direction Y and extends like a long slit. Therefore, at the position immediately before the secondary supply of the developer from the slit nozzle 42, the gas jetted from the discharge port 412 is uniform over the entire width direction of the substrate S in the Y direction, and the discharge range is uniform in the X direction. forms a regulated air curtain. The reason for doing so will be described later in detail.

The rinse section 5 includes a slit nozzle (rinse liquid nozzle) 51 arranged above the substrate S conveyed by the conveying rollers 71 . The slit nozzle 51 has the same configuration as the slit nozzle 31 employed in the first developing section 3, and is arranged so that the discharge port 512 provided on the lower surface of the nozzle main body 511 faces the surface G1 of the substrate S. are placed in The slit nozzle 51 is connected to a rinse liquid supply source 52 . When the rinse liquid supply source 52 pressure-feeds the rinse liquid to the slit nozzle 51 in response to a discharge command from the control unit 8 , the rinse liquid spreads across the width direction Y from the discharge port 512 toward the substrate S conveyed by the conveying rollers 71 . is supplied to the substrate S. By supplying the rinse liquid, the developer adhering to the surface G1 of the substrate S is washed away together with the dissolved resist components, and the development process is stopped. The substrate S thus wetted with the rinsing liquid is transported to the drying section 6 .

The drying section 6 has a pair of air nozzles 61 and 62 . The air nozzles 61 and 62 are arranged above and below the conveying roller 71, respectively. An air supply source 63 is connected to the air nozzles 61 and 62 . Therefore, when the air supply source 63 is activated in response to a drying command from the control unit 8 and the drying air is pressure-fed to the air nozzles 61 and 62, the surface G1 and the back surface G2 of the substrate S transported by the transport rollers 71 are dried. A curtain of drying air is supplied to remove the rinsing liquid adhering to the substrate S. The substrate S thus dried is carried out from the developing device 1 through the outlet 26 by the carrying rollers 71 .

FIG. 2 is a flow chart showing an outline of development processing by the developing device, and more specifically, describes a series of processing performed on one substrate S loaded into the developing device 1. FIG. . In practice, a plurality of substrates S are loaded into the developing device 1 one by one, and these substrates S are processed in parallel in each part of the device.

When the substrate S exposed by the exposure device in the previous process is carried into the developing device 1, the substrate transfer section 7 starts to transfer the substrate S in the X direction (step S101). Then, the developing solution is primarily supplied from the slit nozzles 31 and 32 in the first developing section 3 (step S102). As a result, the substrate S on which the liquid film P of the developer is formed is transported to the second developing section 4 . In the second developing section 4, immediately after the curtain-like air is blown onto the liquid film P on the substrate S from the air nozzle 41 (step S103), the developer is secondary supplied from the slit nozzle 42 (step S104).

After that, the substrate S is subjected to a rinsing process in the rinsing section 5 (step S105) and a drying process in the drying section 6 (step S106), and then carried out (step S107). Since the contents of these processes are publicly known, description thereof is omitted.

FIG. 3 is a diagram schematically showing the liquid film forming process by primary supply of the developer. The primary supply of the developer is performed by slit nozzles 31 and 32 which are arranged close to each other. As shown in FIG. 3A, the upper end of the slit nozzle 31 on the upstream side is inclined toward the (−X) side, that is, toward the upstream side in the transport direction of the substrate S, and the lower lip of the nozzle body 311 is inclined. A surface 313 is substantially horizontal. The dotted line shown in FIG. 3(a) represents the height of the upper surface of the substrate S being transported. As can be seen, the slit nozzle 31 is positioned so that its lip surface 313 is relatively close to the upper surface of the substrate. On the other hand, the slit nozzle 32 on the downstream side is in an upright state with the discharge port 322 facing downward, and the gap between the discharge port 322 and the upper surface of the substrate is larger than that of the slit nozzle 31 .

As shown in FIG. 3B, the developer is discharged from the slit nozzle 31 at the timing when the tip Sa of the substrate S passes through the position directly below the slit nozzle 31 . The discharged developer makes the gap between the lip surface 313 and the upper surface of the substrate S liquid-tight due to the action of surface tension. A uniform thin liquid film is formed by the developer. By reducing the gap between the slit nozzle 31 and the substrate S and making the gap between the lip surface 413 and the upper surface of the substrate S liquid-tight, a uniform liquid film can be formed even if the amount of developer discharged is relatively small. It is possible to form

As shown in FIG. 3C, the developer is supplied from the slit nozzle 32 when the leading edge Sa of the substrate S passes through the position directly below the slit nozzle 32 . Thereby, the thickness of the liquid film on the substrate S is increased. By continuing this process until the post-stage portion Sb of the substrate S passes through the position directly below the slit nozzle 32, a uniform and sufficiently thick liquid film is formed on the entire upper surface of the substrate S as shown in FIG. 3(d). P can be formed.

In order to supply a sufficient amount of developer to develop the resist film satisfactorily, the thickness of the liquid film P must be appropriate. However, if a large amount of developer is supplied from the beginning in order to form a sufficiently thick liquid film P, it is necessary to keep the distance between the nozzle and the substrate S relatively large. This increases the flow of the developer on the substrate S, making it difficult to stably form a continuous and uniform liquid film. As described above, a thin liquid film is formed by the slit nozzle 31 brought close to the substrate S, and the liquid is supplied from the slit nozzle 32 to increase the thickness of the liquid film. It becomes possible to stably form the liquid film P having the

As shown in FIG. 3D, the horizontal distance D in the X direction between the ejection port 322 of the slit nozzle 32 on the downstream side and the ejection port 412 of the air nozzle 41 of the second developing section 4 is defined by the substrate S in the same direction. If it is longer than the length Lx, the liquid film P on the substrate S can be transported while being kept calm. During this time, the photoresist film on the substrate S continues to be in contact with the developer, so that the development process proceeds.

4 and 5 are diagrams for explaining the processing in the second developing section. The development progresses by transporting the substrate S with the liquid film P formed on the upper surface thereof. At this time, the resist material released from the substrate S, oxygen in the air, and the like gradually dissolve into the developer, and the developing ability of the developer gradually decreases. The "developing ability" of the developer as used herein is a concept representing how much resist film the developer can remove. Quantitatively, the developability can be expressed, for example, by the amount of resist that can be dissolved per unit time. As the development progresses, the amount of dissolved resist material and oxygen increases, and furthermore, the developing ability of the developer inevitably decreases with time due to the decrease in the temperature of the solution and the like.

As shown in FIG. 4(a), the liquid film P on the substrate S transported in a quiet state has a profile such that the developing ability decreases toward the side closer to the tip Sa of the substrate S, that is, toward the downstream side in the transport direction. is considered to have This is because, as described above, in the first developing section 3, the developing solution is supplied in order from the front end portion Sa of the substrate S being transported, and therefore, the closer to the front end portion Sa, the more time has passed since the supply. .

In order to compensate for the decrease in developing efficiency caused by such a decrease in developing ability, the second developing section 4 of the developing device 1 additionally supplies the developer (secondary supply). As shown in FIG. 4B, at a portion of the substrate S to which the developer is newly supplied from the slit nozzle 42, as indicated by the solid line in the lower graph of FIG. It is expected that developability will be obtained. However, in practice, as indicated by the dotted line, the new developer mixes with the existing developer in the liquid film P, so that the developing power on the substrate S decreases and spreads toward the upstream side. becomes.

If the transport of the substrate S is continued as it is, the ratio of the new developer to the liquid film P gradually increases, and the liquid film P has a development capability profile different from that originally intended. This contributes to the deterioration of the in-plane uniformity of the development results, particularly the uniformity in the transport direction.

In order to solve this problem, in this embodiment, as shown in FIG. 5A, an air knife is blown onto the liquid film P by the air nozzle 41 immediately before the secondary supply of the developer from the slit nozzle 42 . The blowing of the air knife is performed to block the movement of developer between the upstream side and the downstream side of the blowing position, and specifically has two effects. First, by reducing the thickness of the liquid film P, it is possible to reduce the ratio of the existing developer, that is, the developer whose developing ability has decreased, to be mixed with the newly supplied developer. As a result, the newly supplied developer can process the substrate S while maintaining the original developing ability.

Secondly, the newly supplied developer is prevented from flowing upstream beyond the spraying position of the air knife (this phenomenon is hereinafter referred to as "overflow"). This avoids variations in the developability profile on the upstream side before the secondary supply of developer occurs.

The dotted line in FIG. 5(a) schematically shows the profile of the developing ability at this time. A profile close to the ideal profile indicated by the solid line by reducing the contamination of the existing developer into the secondary supplied developer and suppressing the overflow of the secondary supplied developer to the upstream side. is obtained.

Even when the substrate S was transported in this state, as shown in FIG. 5B, the profile near the boundary between the newly supplied developer Ln and the existing developer Lo maintained its original shape. As the substrate S moves, it shifts to the upstream side. Therefore, the development conditions are kept substantially constant from the front end portion Sa to the rear end portion Sb of the substrate S, and excellent in-plane uniformity can be obtained in the development processing result.

FIG. 6 is a diagram illustrating the effect of the air knife in this embodiment. The inventor of the present application verified the effect of the air knife of this embodiment through the following experiments. In the experiment, using the developing apparatus 1 shown in FIG. 1, test substrates prepared for the experiment were developed under various developing conditions, and the uniformity of processing was evaluated from the development results. The development conditions were as follows: (1) only primary supply of the developer without using an air knife; (2) primary and secondary supply; A case using an air knife in addition to the supply was used.

FIG. 6(a) shows the test substrate St used in the experiment. The test substrate St is a rectangular glass substrate having a photoresist film formed on its surface, and predetermined test patterns TP are formed by exposure at five positions A to E near the four corners and near the center. As the test pattern TP, one having a line-and-space structure with a predetermined pitch was used, and the line width of the pattern after development was measured at a plurality of points in each pattern to obtain the variation 3σ.

FIG. 6B is a diagram showing an example of experimental results. "Position A" and the like show variations in line width measurement results within the test pattern TP at each position, and "Overall" on the right end shows variations in all line width measurement results without distinguishing between positions A to E. . In the case (1) in which the developer is primarily supplied, the line width has a relatively large variation at each position A to E, and the overall variation is also large. The fact that the overall variation is greater than the variation at each position A to E indicates that even with the same pattern, the line width after development differs depending on the position within the substrate.

In the case (2) in which the secondary supply of the developer is added, the variation at each position A to E is improved, but the overall variation is not much improved. In other words, the secondary supply has the effect of suppressing variations in line width in a relatively narrow range within the substrate, but it is not necessarily sufficient to suppress variations in a wider range.

Furthermore, in case (3) where an air knife is added, in addition to further improving the variation at each position A to E, the overall variation is also suppressed, and the extent of this is the same at each position A to E. not much different from volatility. Therefore, by separating the primarily supplied liquid film and the secondarily supplied developer by an air knife, in other words, by blocking the interference between the two, the in-plane uniformity of the entire substrate in the development process can be improved. can be enhanced.

Since the excessive flow of the developer in the liquid film can cause a decrease in the uniformity of processing, the amount or flow velocity of the gas jetted from the air nozzle 41 should be as small as possible within the range where overflow can be prevented. Better. It should be noted that blowing such a strong air current as to expose the surface of the substrate S should be naturally avoided. Since the appropriate gas injection amount may vary depending on various parameters such as the physical properties of the resist material and developer, the type of pattern, and the transport speed, it is necessary to determine the optimum conditions by conducting experiments in advance.

<Second embodiment>
Next, a second embodiment of the developing device according to the invention will be described. In the above-described embodiment, the air nozzle 41 arranged upstream and adjacent to the slit nozzle 42 for secondary supply of the developer forms an air knife, whereby the developer that is primarily supplied and forms the liquid film P is formed. It is separated from the developer supplied secondarily. On the other hand, in the developing device of the second embodiment described below, instead of the air knife, a blade member is arranged so as to closely face the upper surface of the substrate S. As shown in FIG. As a result, part of the developer forming the liquid film P is scraped off to regulate the thickness of the liquid film P, and the secondarily supplied developer is prevented from overflowing. Except for this point, the configuration of the developing device is the same as that of the first embodiment, so a detailed description thereof will be omitted.

FIG. 7 is a diagram showing the essential parts of a second embodiment of the developing device according to the present invention. In this embodiment, a blade member 43 is provided instead of the air nozzle. Specifically, as shown in FIG. 7(a), the blade member 43 is a flat plate member extending along the width direction Y adjacent to the upstream side of the slit nozzle 42, that is, the (−X) side. be. The lower end of the blade member 43 extends in the horizontal direction, and is supported so as to face the upper surface of the substrate S to be transported in close proximity with a predetermined gap therebetween. For example, it can be attached to the (-X) side surface of the slit nozzle 42, but a separate support mechanism may be provided. Also, the slit nozzle and the blade member may be integrally formed.

As shown in FIG. 7B, the size of the gap between the lower end of the blade member 43 and the upper surface of the substrate S is smaller than the thickness of the liquid film P formed on the substrate S by the first developing section 3 . Therefore, the liquid film P conveyed together with the substrate S comes into contact with the blade member 43 and is further conveyed in a state where the film thickness is regulated by the size of the gap. The slit nozzle 42 secondary-supplies the developer to the liquid film whose thickness has been reduced in this way, so that it is possible to suppress the deterioration of the developing ability due to the mixing of the existing developer. Further, even if the secondary supplied developer flows upstream, the existing developer flowing from the blade member 43 and its lower portion prevents it from spreading further upstream beyond the blade member 43. . That is, overflow can be prevented.

Also in this embodiment, the horizontal distance between the discharge port 322 of the slit nozzle 32 of the first developing section 3 and the blade member 43 is larger than the length Lx of the substrate S in the transport direction X (FIG. 3D). is desirable. By doing so, the liquid film P can be held calmly until the liquid film P contacts the blade member 43 after the formation of the liquid film P covering the entire substrate S.

As described above, the blade member 43 opposed to the substrate S with a small gap also forms the liquid film P when the developer is secondarily supplied, similar to the air knife by the air nozzle 41 in the first embodiment. It is possible to regulate the thickness and prevent the secondarily supplied developer from spreading to the upstream side.

<Others>
As described above, in the developing device 1 of this embodiment, the substrate conveying section 7 functions as the "conveying section" of the present invention, and the first developing section 3 and the second developing section 4 function as the "conveying section" of the present invention. function as a "primary supply section" and a "secondary supply section" respectively. In the second developing section 4, which is the secondary supply section, the slit nozzle 42 functions as the "secondary supply nozzle" of the present invention. The ejection port 422 of the slit nozzle 42 corresponds to the "liquid ejection port" of the invention, and the ejection port 412 of the air nozzle 41 corresponds to the "gas ejection port" of the invention. Furthermore, the ejection port 322 of the slit nozzle 32 corresponds to the "liquid ejection port" of the primary supply section in the present invention.

Further, while the air nozzle 41 in the first embodiment corresponds to the "gas injection nozzle" of the invention, the blade member 43 in the second embodiment corresponds to the "blocking member" of the invention. Each of these functions as the "blocking section" of the present invention.

The present invention is not limited to the above-described embodiments, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, in the above embodiment, two slit nozzles 31 and 32 are combined when forming the liquid film P of the developer on the substrate S. As shown in FIG. However, the configuration for liquid film formation is not limited to this and is arbitrary. For example, the liquid film may be formed by a single slit nozzle, or the liquid film may be formed by a liquid supply mechanism other than the slit nozzle. For example, the liquid film may be formed without transporting the substrate S in one direction (for example, while it is stopped or rotated).

Moreover, although the air nozzle 41 and the slit nozzle 42 are formed separately in the first embodiment, they may be formed integrally. In this case, the positional relationship between the gas ejection port and the liquid ejection port, the shape of the flow path, etc. can be set with a higher degree of freedom. Similarly, the blade member 43 in the second embodiment may be formed integrally with the slit nozzle 42 .

In the above-described embodiments, the substrate S corresponds to an example of the "substrate" of the present invention, but the "substrate" of the present invention also includes substrates other than the substrate S, such as semiconductor wafers and solar cell substrates. included.

Moreover, in the above-described embodiment, the substrate S is moved relative to the nozzles by transporting the substrate S immediately below the fixedly arranged nozzles. However, it is possible to employ the same technique as described above even in a developing device that performs development processing by moving the nozzle while the substrate S is fixed or conveyed.

As described above by exemplifying specific embodiments, in the developing device and the developing method according to the present invention, for example, the blocking section directs the gas toward the liquid film on the substrate at a position close to the liquid ejection port. It may be configured to jet and form an air curtain extending in the width direction orthogonal to the conveying direction with the gas. According to such a configuration, the thickness of the liquid film on the substrate is regulated by blowing the gas, and the newly supplied developer is prevented from spreading upstream beyond the position where the gas is blown. can be done.

In this case, the gas may be uniformly injected over the entire width of the substrate. By doing so, it is possible to improve the uniformity of processing in the width direction. Specifically, it is possible to prevent the existing developer swept away by the gas and the newly supplied developer from flowing in the width direction and causing uneven development.

Further, the shortest distance between the liquid ejection port for ejecting the developer for the primary supply and the gas ejection port may be larger than the length of the substrate in the transport direction. According to such a configuration, there is a period in which the liquid film on the substrate can be maintained calmly without any external factors disturbing the liquid film on the substrate during the transportation. It is possible to proceed well and stably.

Further, for example, the blocking portion includes a blocking member extending in the width direction perpendicular to the transport direction in the vicinity of the liquid ejection port and having a lower end extending horizontally on the upper surface of the substrate to be transported. They may be opposed to each other with a gap smaller than the thickness of the liquid film. According to such a configuration, the blocking member comes into contact with the liquid film and regulates the thickness of the liquid film passing through the gap. At the same time, the blocking member prevents newly supplied developer from spreading upstream over the gap.

In this case, regarding the liquid ejection port for ejecting the developer for primary supply, the shortest distance between the liquid ejection port and the blocking member may be larger than the length of the substrate in the transport direction. good. According to such a configuration, there is a period in which the liquid film on the substrate can be maintained calmly without any external factors disturbing the liquid film on the substrate during the transportation. It is possible to proceed well and stably.

Further, for example, the blocking member may be provided on the side surface on the upstream side in the transport direction among the side surfaces of the secondary supply nozzle. According to such a configuration, it is easy to keep the distance between the blocking member and the liquid ejection port of the secondary supply nozzle constant, and it is unnecessary to separately provide a mechanism for supporting the blocking member.

Further, for example, the secondarily supplied developer may be discharged uniformly over the entire width of the substrate. By doing so, it is possible to improve the uniformity of processing in the width direction. Specifically, it is possible to suppress the occurrence of development unevenness in the width direction.

Alternatively, the formation of the liquid film, the regulation of its thickness, and the secondary supply of the developer may be sequentially performed while the substrate is being transported at a constant speed. According to such a configuration, the processing for each portion of the substrate can be progressed at a constant processing pitch regardless of the position, so it is possible to realize uniform development processing.

INDUSTRIAL APPLICABILITY The present invention can be applied to general development techniques in which development is performed by supplying a developer to a substrate having an exposed photoresist film.

1 developing device 3 first developing section (primary supply section)
4 Second developing section (secondary supply section)
7 Substrate transfer section (transfer section)
8 control unit (injection control unit)
41 air nozzle (gas injection nozzle, blocking part)
42 slit nozzle (secondary supply nozzle)
43 blade member (blocking member, blocking portion)
322 discharge port (of slit nozzle 32) (liquid discharge port of primary supply unit)
412 (air nozzle 41) discharge port (gas discharge port)
422 ejection port (liquid ejection port) (of slit nozzle 42)
P Liquid film S Substrate X Transport direction Y Width direction

Claims (10)

a transport unit that horizontally transports a substrate having an exposed photoresist film on its surface while supporting the substrate in a horizontal position with the photoresist film facing upward;
a primary supply unit that supplies a developer to the upper surface of the substrate supported by the transport unit and covers the upper surface of the substrate with a liquid film of the developer;
a secondary supply section that additionally supplies the developer onto the upper surface of the substrate being conveyed, on the downstream side of the primary supply section in the conveyance direction of the substrate;
The secondary supply unit is
a secondary supply nozzle having a liquid ejection port for ejecting the developer onto the upper surface of the substrate;
Thickness of the liquid film that is disposed adjacent to the liquid ejection port on the downstream side of the primary supply portion and on the upstream side of the liquid ejection port in the transport direction and that is transported to a position facing the liquid ejection port. a blocking portion that regulates the thickness of the substrate and prevents the developer supplied from the liquid ejection port to the substrate from flowing upstream in the transport direction;
The blocking section has a gas injection nozzle for injecting gas toward the liquid film on the substrate from a gas ejection port arranged close to the liquid ejection port. forming an air curtain extending to
The primary supply section has a liquid ejection port for ejecting the developer onto the upper surface of the substrate transported by the transport section, and is the shortest distance between the liquid ejection port and the gas ejection port of the primary supply section. A developing device, wherein the distance is greater than the length of the substrate in the transport direction. 2. The developing device according to claim 1, wherein the gas injection nozzle uniformly injects the gas over the entire width of the substrate. a transport unit that horizontally transports a substrate having an exposed photoresist film on its surface while supporting the substrate in a horizontal position with the photoresist film facing upward;
a primary supply unit that supplies a developer to the upper surface of the substrate supported by the transport unit and covers the upper surface of the substrate with a liquid film of the developer;
a secondary supply section that additionally supplies the developer onto the upper surface of the substrate being conveyed, on the downstream side of the primary supply section in the conveyance direction of the substrate;
The secondary supply unit is
a secondary supply nozzle having a liquid ejection port for ejecting the developer onto the upper surface of the substrate;
Thickness of the liquid film that is disposed adjacent to the liquid ejection port on the downstream side of the primary supply portion and on the upstream side of the liquid ejection port in the transport direction and that is transported to a position facing the liquid ejection port. a blocking portion that regulates the thickness of the substrate and prevents the developer supplied from the liquid ejection port to the substrate from flowing upstream in the transport direction;
The blocking section has a blocking member extending in a width direction orthogonal to the transport direction in proximity to the liquid ejection port, and a lower end of the blocking member extends horizontally and the substrate being transported is provided. , the primary supply unit facing the top surface of the substrate with a gap smaller than the thickness of the liquid film formed on the substrate. 4. The developing device according to claim 3, wherein the blocking member is provided on a side surface of the secondary supply nozzle on an upstream side in the conveying direction. The primary supply section has a liquid ejection port for ejecting the developer onto the upper surface of the substrate transported by the transport section, and the shortest distance between the liquid ejection port of the primary supply section and the blocking member. is greater than the length of the substrate in the conveying direction. 6. The developing device according to any one of claims 1 to 5, wherein the secondary supply nozzle uniformly discharges the developer over the entire width direction of the substrate perpendicular to the transport direction. In the developing method for developing the photoresist film on the exposed substrate surface with a developer,
a step of primarily supplying a developer from a primary supply unit to the upper surface of the substrate supported in a horizontal position with the photoresist film facing upward, and covering the upper surface of the substrate with a liquid film of the developer;
horizontally transporting the substrate on which the liquid film is formed;
discharging the developer onto the upper surface of the substrate from a liquid discharge port of a secondary supply nozzle arranged above the substrate being transported;
A blocking portion disposed close to the liquid ejection port on the upstream side of the liquid ejection port in the transport direction of the substrate regulates the thickness of the liquid film transported to a position facing the liquid ejection port. and suppressing the developer supplied from the liquid ejection port to the substrate from flowing upstream in the transport direction,
The blocking section has a gas injection nozzle for injecting gas toward the liquid film on the substrate from a gas ejection port arranged close to the liquid ejection port. forming an air curtain extending to
The primary supply unit has a liquid ejection port for ejecting the developer onto the upper surface of the substrate being transported , and the shortest distance between the liquid ejection port and the gas ejection port of the primary supply unit is A developing method, wherein the length of the substrate in the conveying direction is longer than that of the substrate. 8. The shielding unit according to claim 7, wherein the blocking part injects gas toward the liquid film on the substrate at a position close to the liquid ejection port, and forms an air curtain extending in a width direction orthogonal to the transport direction with the gas. Developing method as described. In the developing method for developing the photoresist film on the exposed substrate surface with a developer,
a step of primarily supplying a developer onto the upper surface of the substrate supported in a horizontal position with the photoresist film facing upward, and covering the upper surface of the substrate with a liquid film of the developer;
horizontally transporting the substrate on which the liquid film is formed;
discharging the developer onto the upper surface of the substrate from a liquid discharge port of a secondary supply nozzle arranged above the substrate being transported;
A blocking portion disposed close to the liquid ejection port on the upstream side of the liquid ejection port in the transport direction of the substrate regulates the thickness of the liquid film transported to a position facing the liquid ejection port. and suppressing the developer supplied from the liquid ejection port to the substrate from flowing upstream in the transport direction,
The blocking portion includes a blocking member extending in a width direction perpendicular to the transport direction in the vicinity of the liquid ejection port, and having a bottom end extending horizontally. A developing method in which the two liquid films are opposed to each other with a gap smaller than the thickness of the liquid film. 10. The method according to any one of claims 7 to 9, wherein the formation of the liquid film, the regulation of the thickness of the liquid film by the blocking section, and the secondary supply of the developer are sequentially performed while the substrate is conveyed at a constant speed. development method.

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