JP3704059B2 - Development processing method and development processing apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a substrate developing method and a developing apparatus.
[0002]
[Prior art]
For example, in a photolithography process in a semiconductor device manufacturing process, a resist solution is applied to the wafer surface, a resist coating process for forming a resist film, an exposure process for exposing a pattern to the wafer, and a development for developing the exposed wafer. Processing and the like are sequentially performed to form a predetermined circuit pattern on the wafer.
[0003]
In the development process described above, a developer supply nozzle that is longer than the diameter of the wafer and has a plurality of supply ports along its longitudinal direction moves from one end of the wafer to the other while discharging the developer onto the wafer. Then, the developer is supplied to the entire surface of the wafer. Then, when a liquid film of the developer is formed on the wafer, the wafer is developed while standing still for a predetermined time in that state. At this time, on the wafer, the resist film in the exposed portion that has become soluble in the developer due to exposure and the developer chemically react with each other, and the exposed portion is melted, whereby the development of the wafer proceeds.
[0004]
[Problems to be solved by the invention]
By the way, when the developer supply nozzle is moved in a predetermined direction as described above and the developer is supplied, the direction opposite to the moving direction of the developer supply nozzle, that is, from the other end of the wafer toward the one end, It has been clarified through experiments by the inventors that a so-called developer flow phenomenon occurs in which the supplied developer flows.
[0005]
However, under this phenomenon, when a high-concentration developer that is on the unexposed area and has not yet been used for a chemical reaction flows into the adjacent exposed area, the speed of the chemical reaction in the exposed area increases. Then, the developing speed of the portion is increased compared to the other portions. As a result, the line width of that part becomes narrower than other parts. On the other hand, when the low-concentration developer used in the chemical reaction in the exposed area flows into the adjacent exposed area, the reaction speed of the exposed area decreases and the developing speed of that area decreases. Therefore, the line width of that part becomes thicker than other parts. That is, the development speed in the wafer surface becomes non-uniform due to the above phenomenon, thereby causing variations in the line width of the circuit pattern finally formed on the wafer.
[0006]
The present invention has been made in view of the above points, and eliminates unevenness in the development speed in the surface of a substrate such as a wafer caused by the flow phenomenon of the developer, and finally a uniform line width is formed. It is an object of the present invention to provide a development processing method and a development processing apparatus.
[0007]
[Means for Solving the Problems]
According to the first aspect of the present invention, there is provided a method of developing a substrate by supplying the developer to the substrate surface while the developer supply means moves relative to the substrate, and the developer is applied to the substrate surface. And a second step in which the substrate is developed for a first predetermined time,
The second step is after the first step Stopping the substrate for a second predetermined time and developing it statically; After the second predetermined time has elapsed, Rotate the substrate The developer on the substrate surface is stirred A step of homogenizing the concentration of the developer on the substrate, and a step of measuring the thickness of the liquid film of the developer and then changing at least the time for rotating the substrate based on the measurement result. A development processing method is provided.
[0008]
Even if the developer flow phenomenon as described above occurs, the developer on the surface of the substrate is stirred during the second step in which the substrate is developed as in claim 1, thereby exposing the exposure unit, Since both unexposed portions are covered with a developer having a uniform concentration, the developing speed becomes uniform within the substrate surface. According to the knowledge of the inventors, the reaction product produced by the progress of development is stirred and scattered sparsely, so that the concentration of the developer becomes uniform.
This can be achieved regardless of pattern density. Therefore, variation in the line width of the circuit pattern finally formed on the substrate is suppressed. Note that the second predetermined time after the completion of the first step after the completion of the first step is that the chemical reaction of the developer does not progress so much immediately after the start of development, and the concentration of the developer is within the substrate surface. Because it does not change, stirring at that time is not effective and rather hinders development. The second predetermined time is preferably a time from when the developing solution is supplied onto the substrate until the chemical reaction of development in the exposure portion proceeds by about 50% to 80%. For example, the first predetermined time is 60 seconds. In such a case, about 3 to 15 sec is preferable from the result of the inventor's model experiment.
[0009]
Also By rotating the substrate, the developer on the substrate is moved by centrifugal force, and at the same time, the developer is stirred. By doing so, the concentration of the developer on the substrate becomes uniform and the development speed becomes uniform, so that a circuit pattern having a predetermined line width is formed on the substrate. It is important that the substrate is rotated at an appropriate time, rotational speed, and rotational acceleration. Particularly, regarding the rotational speed, from the results of the inventor's model experiment, an 8-inch wafer is used. For a wafer of 100 rpm to 1000 rpm and 12 inch size, 30 rpm to 1000 rpm is preferable, and the rotation time is preferably about 2 seconds.
[0010]
Further, the stirring step by the rotation may be performed by rotating the substrate forward and then inverting it. In this case, it is preferable that the rotation speed at the time of reversal is higher than the rotation speed at the time of forward rotation. As a result, the reaction products are less uneven and the uniformity of the development process is further improved.
[0011]
The invention of claim 3 is the development processing method of claim 2, wherein the rotation of the substrate is performed so that the thickness of the developer after the stirring step of the developer is not less than a predetermined thickness. A development processing method is provided. Thus, by setting the thickness of the developer after the stirring step to be a predetermined thickness or more, the developer on the substrate is excessively shaken by the rotation of the substrate in the stirring step, and the developer Therefore, it is possible to prevent such a problem that the thickness of the liquid becomes too thin and the developing solution is dried and development is not performed in the subsequent development processing. Note that the thickness of the developer is adjusted by controlling the rotation time, rotation speed, and rotation acceleration of the substrate, and is preferably 8 μm or more according to the experiment results of the inventors.
[0012]
Said By measuring the thickness of the developer after the stirring step and changing the rotation time based on the measurement result, the thickness of the developer on the substrate to be processed next can be adjusted to a predetermined thickness. . Therefore, even when the thickness of the developer fluctuates for some reason, the rotation time is immediately reduced. Fix and developer It is possible to prevent a large amount of defective products from being generated. Stirring “After the process” means from immediately after the stirring process to the end of the second process.
[0013]
Also, based on the measurement results of the developer thickness after the developer agitation step , Of substrate rotation The acceleration may be changed. Even in this case, the thickness of the developing solution is corrected, and the developing process can be suitably performed while maintaining a suitable thickness.
[0014]
In the above-described invention, the first step may be performed by supplying the developer to the substrate while the developer supply means moves from one end to the other end of the substrate. . Thus, when the developer supply means moves from one end of the substrate to the other end to form a developer film on the substrate, the supplied developer has a speed in a certain direction with respect to the substrate. Therefore, the influence of the developer flow phenomenon described above appears remarkably. Therefore, as described above, by performing the agitation process during the development process of the substrate, the development process is performed uniformly within the substrate surface. The developing solution supply means in this case is formed, for example, longer than the diameter of the substrate, has a plurality of supply ports along the longitudinal direction, and is movable in a direction substantially perpendicular to the longitudinal direction. Proposed.
[0015]
In this case, after stirring, for example, the developer on the substrate is shaken off, the developer supply means is further moved in the opposite direction, that is, while moving from the other end of the substrate to the one end with respect to the substrate surface. And a step of supplying the developer again. This can further improve the uniformity of the development process.
[0016]
The first step may be performed by supplying the developer to the substrate while the developer supply means is stopped above the substrate and the substrate is rotating. When the developing solution supply means stops or moves on the substrate while the substrate is rotating, the developing solution may be supplied to the substrate. As described above, when supplying the developer by rotating only the substrate while the developer supply means is stopped, or when supplying the developer to the rotating substrate while stopping or moving the developer supply means. However, by performing the stirring step, the uneven density of the developer caused by the so-called developer flow phenomenon described above is eliminated, and the development is performed at a uniform speed in the substrate surface.
[0017]
In any case, the method may further include a step of supplying the developer again to the substrate surface while stirring, for example, shaking off the developer on the substrate and further rotating the substrate in the opposite direction. Good. This can further improve the uniformity of the development process.
[0018]
The development processing apparatus of the present invention is an apparatus for developing a substrate by supplying the developer to the surface of the substrate while moving the developer supply means relative to the substrate, and holding the substrate. It is possible to propose a development processing apparatus including a rotation driving member that rotates and a rotation control device that reverses the rotation driving member forward and backward after supplying the developer.
[0019]
In this case, it further has a measuring device for measuring the film thickness of the developer supplied to the substrate surface, and based on the measurement result by the measuring device, Board rotation time And a control device for controlling the developing time when developing the substrate by stopping the rotation driving member after the rotation of the substrate based on the measurement result by the measuring device. You may comprise as follows.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described. The development processing method according to the present embodiment is performed by a development processing apparatus. FIG. 1 is a plan view of a coating and developing treatment system 1 having the developing treatment apparatus, FIG. 2 is a front view of the coating and developing treatment system 1, and FIG. 3 is a rear view of the coating and developing treatment system 1. .
[0021]
As shown in FIG. 1, the coating and developing treatment system 1 carries, for example, 25 wafers W in and out of the coating and developing treatment system 1 from the outside in units of cassettes and carries the wafers W in and out of the cassettes C. A cassette station 2, a processing station 3 in which various processing devices for performing predetermined processing in a sheet-fed process in the coating and developing processing step are arranged in multiple stages, and an exposure (not shown) provided adjacent to the processing station 3 The interface unit 4 that transfers the wafer W to and from the apparatus is integrally connected.
[0022]
In the cassette station 2, a plurality of cassettes C can be placed in a line in a X direction (vertical direction in FIG. 1) at a predetermined position on the cassette placement table 5 serving as a placement portion. The wafer transfer body 7 that can be transferred in the cassette arrangement direction (X direction) and the wafer arrangement direction (Z direction; vertical direction) of the wafer W accommodated in the cassette C is movable along the transfer path 8. It is provided so that each cassette C can be selectively accessed.
[0023]
The wafer carrier 7 has an alignment function for aligning the wafer W. As will be described later, the wafer carrier 7 is configured to be accessible also to the extension devices 32 belonging to the third processing device group G3 on the processing station 3 side.
[0024]
In the processing station 3, a main transfer device 13 is provided at the center thereof, and various processing devices are arranged in multiple stages around the main transfer device 13 to form a processing device group. In the coating and developing processing system 1, four processing device groups G1, G2, G3, and G4 are arranged. The first and second processing device groups G1 and G2 are arranged on the front side of the developing processing system 1. The third processing unit group G3 is disposed adjacent to the cassette station 2, and the fourth processing unit group G4 is disposed adjacent to the interface unit 4. Further, as an option, a fifth processing unit group G5 indicated by a broken line can be separately arranged on the back side. The main transfer device 13 can carry in and out the wafer W with respect to various processing devices described later arranged in these processing device groups G1, G2, G3, and G4. Note that the number and arrangement of the processing apparatus groups vary depending on the type of processing performed on the wafer W, and the number of processing apparatus groups may not be four as long as it is one or more.
[0025]
In the first processing unit group G1, for example, as shown in FIG. 2, a resist coating unit 17 for applying a resist solution to the wafer W and a development processing unit 18 for performing the development processing method according to this embodiment are provided. Are arranged in two stages in order. Similarly, in the case of the processing unit group G2, the resist coating unit 19 and the development processing unit 20 are stacked in two stages in order from the bottom.
[0026]
In the third processing unit group G3, for example, as shown in FIG. 3, a cooling device 30 for cooling the wafer W, an adhesion device 31 for improving the fixability between the resist solution and the wafer W, and an extension for waiting the wafer W The apparatus 32, pre-baking apparatuses 33 and 34 for drying the solvent in the resist solution, and post-baking apparatuses 35 and 36 for performing the heat treatment after the development process are stacked in, for example, seven stages from the bottom.
[0027]
In the fourth processing unit group G4, for example, a cooling unit 40, an extension / cooling unit 41 that naturally cools the mounted wafer W, an extension unit 42, a cooling unit 43, and a post-exposure baking unit 44 that performs a heating process after the exposure process. , 45, post-baking devices 46, 47, etc. are stacked in, for example, eight stages from the bottom.
[0028]
A wafer carrier 50 is provided at the center of the interface unit 4. The wafer carrier 50 is configured to be freely movable in the X direction (vertical direction in FIG. 1) and Z direction (vertical direction) and rotated in the θ direction (rotating direction around the Z axis). , Access to the extension / cooling device 41, the extension device 42, the peripheral exposure device 51 and the exposure device (not shown) belonging to the fourth processing unit group G4, and the wafer W can be transferred to each of them. Yes.
[0029]
Next, the configuration of the development processing apparatus 18 described above will be described in detail. As shown in FIGS. 4 and 5, a spin chuck 60, which is a suction holding means for sucking and holding the wafer W, is provided in the casing 18 a of the development processing apparatus 18. Below the spin chuck 60, there is provided a rotation drive mechanism 61 equipped with, for example, a motor for rotating the spin chuck 60. The rotation driving mechanism 61 is controlled to rotate freely by a rotation control device 62, and is configured to rotate or stop the wafer W at a predetermined rotation time, rotation speed, and rotation acceleration. Has been. Further, the rotation driving mechanism 61 of the spin chuck 60 has a function of allowing the spin chuck 60 to move up and down. When the wafer W is loaded and unloaded, the spin chuck 60 is moved up and down to move the main chuck 13. The wafer W can be delivered between the two.
[0030]
Outside the outer periphery of the spin chuck 60, an annular cup 65 having an open upper surface is provided so as to surround the outer periphery of the spin chuck 60, and the wafer that is sucked and held on the spin chuck 60 and rotated. The developer and the like scattered from W are received so that peripheral devices are not contaminated. At the bottom of the cup 65, there are provided a drain pipe 63 for discharging the developer and the like scattered from the wafer W and the like, and an exhaust pipe 64 for exhausting the inside of the cup 65. The cup 65 is provided with a back surface cleaning nozzle 67 for supplying a cleaning liquid to the back surface of the wafer W held on the spin chuck 60 and cleaning the back surface of the wafer W. The cup 65 is provided with a drive mechanism (not shown) so that the entire cup 65 moves up and down and can be retracted downward so as not to hinder the movement of the developer supply nozzle 70 described later. Yes.
[0031]
Outside the cup 65, a square-shaped out cup 66 having an open upper surface is provided so as to surround the cup 65. The wafer W that cannot be received by the cup 65 and a developer supply nozzle 70 described later. The developer etc. from is received there. The out cup 66 is provided with a drive mechanism (not shown) that allows the out cup 66 to move up and down. For example, the out cup 66 rises when the wafer W is cleaned, and the scattered cleaning liquid and the like are collected more completely. It can be done.
[0032]
As shown in FIG. 5, a developer supply nozzle 70 as a developer supply means for supplying the developer to the wafer W and a cleaning nozzle 71 for supplying the cleaning liquid to the upper surface of the wafer W are out in the casing 18a. It is arrange | positioned on both sides on both sides of the cup 66.
[0033]
As shown in FIG. 5, the developer supply nozzle 70 is held so as to be suspended by an arm 75. The arm 75 is configured to be movable on a rail 76 extending in one direction (in the direction of arrow M in FIG. 5) in the casing 18a, and its moving speed and timing are controlled by a movement control device 77. Yes. With this configuration, the developer supply nozzle 70 can move in parallel on the wafer W along the M direction. The arm 75 has a structure having a motor or the like, and the arm 75 moves in the vertical direction, so that the distance between the tip of the discharge port of the developer supply nozzle 70 and the wafer W can be optimally adjusted when supplying the developer. It is configured as follows.
[0034]
On the other hand, a cleaning nozzle 71 that discharges, for example, pure water, which is a cleaning liquid, is supported by a rinse arm 80, and this rinse arm 80 is configured to be movable on a rail 76 by a drive mechanism (not shown). Accordingly, the cleaning nozzle 71 is movable in the M direction similarly to the developer supply nozzle 70. Note that when the rinse arm 80 is positioned above the center of the wafer W, the cleaning nozzle 71 is installed so that the cleaning liquid can be supplied to the center of the wafer W, for example. By doing so, the cleaning liquid supplied onto the rotating wafer W is diffused over the entire surface of the wafer W and cleaned without any spots on the entire surface of the wafer W. Note that the cleaning liquid may be supplied onto the wafer W while moving the cleaning nozzle 71 from the central portion of the wafer W to the peripheral portion.
[0035]
The developer supply nozzle 70 has an elongated shape as shown in FIGS. 5 and 6, and its length L is at least larger than the diameter of the wafer W. One end of a pipe 85 through which a developer from a developer supply source (not shown) flows into the developer supply nozzle 70 is connected to the upper portion of the developer supply nozzle 70. Below the developer supply nozzle 70, a plurality of developer supply ports 86 are provided in a row in the longitudinal direction. Further, as shown in FIG. 7, a long liquid reservoir 87 communicating with each of the developer supply ports 86 is formed inside the developer supply nozzle 70, and the developer supply nozzle 70 is connected through a pipe 85. The developer that has flowed into 70 is temporarily stored, and the developer can be simultaneously discharged from each developer supply port 86 at the same flow rate and pressure.
[0036]
As shown in FIGS. 4 and 5, a cleaning tank 88 for cleaning the developer supply nozzle 70 is provided at the standby position T of the developer supply nozzle 70 located outside the out cup 66. The cleaning tank 88 is formed in a concave shape so as to receive the elongated developer supply nozzle 70, and the cleaning tank 88 is used for cleaning the developer attached to the developer supply nozzle 70. A predetermined solvent is stored.
[0037]
The casing 18a is provided with a transfer port 90 for loading and unloading the wafer W by the transfer device 13 and a shutter 91 for opening and closing the transfer port 90. Except when the wafer W is loaded and unloaded, The shutter 91 is closed to prevent the processing liquid from scattering from the casing 18a, and a predetermined atmosphere is maintained.
[0038]
Next, the development processing method performed by the development processing apparatus 18 configured as described above will be described together with the process of the photolithography process performed by the coating and developing processing system 1.
[0039]
First, the wafer carrier 7 picks up one unprocessed wafer W from the cassette C and carries it into the adhesion apparatus 31 belonging to the third processing unit group G3. In this adhesion device 31, the wafer W coated with an adhesion enhancing agent such as HMDS for improving the adhesion with the resist solution is conveyed by the main conveying device 13 to the cooling device 30 and cooled to a predetermined temperature. Then, the wafer W cooled to a predetermined temperature is transferred to the resist coating device 17 or 19, and a resist solution is applied onto the wafer W to form a resist film. Thereafter, the wafer W is transferred to the pre-baking apparatus 34 or 35, subjected to heat treatment, and then transferred to the extension / cooling apparatus 41.
[0040]
Next, the wafer W is taken out from the extension / cooling device 41 by the wafer carrier 50 and then transferred to the exposure device (not shown) through the peripheral exposure device 51. After the exposure processing, the wafer W is transferred to the extension device 42 by the wafer transfer body 50 and then held by the main transfer device 13. Next, the wafer W is sequentially transferred to the post-exposure baking apparatus 44 or 45 and the cooling apparatus 43, subjected to predetermined processing by these treatment apparatuses, and then transferred to the development processing apparatus 18 or 20.
[0041]
The above-described development process will be described in detail. First, the pre-processed wafer W is loaded into the development processing apparatus 18 by the main transfer device 13 and is sucked and held on the spin chuck 60. Then, the developer supply nozzle 70 waiting in the cleaning tank 88 at the standby position T moves to the start position S (shown in FIG. 5) in the cup 65 and outside the one end portion of the wafer W. .
[0042]
Then, at the start position S, discharge of the developer from the developer supply nozzle 70 is started, and trial discharge is performed until the discharge state is stabilized.
[0043]
Hereinafter, the developing solution supply step as the first step and the developing step of the wafer W as the second step will be described with reference to FIG. 8. First, while the developing solution supply nozzle 70 discharges the developing solution, The developer supplying process is performed while moving from the start position S outside one end of the wafer W to the end position E outside the other end at a speed of 60 to 200 mm / s. At this time, as shown in FIG. 9, the developer is supplied to the entire surface of the wafer W, and a liquid film of the developer having a predetermined thickness, for example, about 1 mm is formed. When the diameter of the wafer W is about 200 mm, the time required for supplying the developer by the developer supply nozzle 70 is 1 to 3 seconds. At this time, a flow phenomenon that is a so-called fluid movement of the developing solution that flows in the direction opposite to the moving direction of the developing solution supply nozzle 70 (the negative direction in the M direction), that is, the direction from the end position E toward the start position S occurs.
[0044]
Then, as described above, the developing solution is supplied onto the wafer W by the developing solution supply nozzle 70, and at the same time, the development of the wafer W is started, and the wafer W is kept stationary for a predetermined time as a second predetermined time, for example, 8 seconds. Develop in the state where
[0045]
When the static development for 8 seconds is completed (for 9 to 11 seconds from the start of the developer supply process to the wafer W), the stirring for eliminating the difference in density caused by the developer supply time difference of the developer on the wafer W next time The rotation of the wafer W as a process is started. At this time, the wafer W is rotated at a predetermined rotation time set in a development processing program of an apparatus controller (not shown), for example, 2.0 sec, at a predetermined rotation speed, for example, 1000 rpm, and at a predetermined acceleration, for example, 1000 rpm / s. It is controlled and rotated. The values of these parameters are values such that the developer that changes depending on the exposure pattern at the time of exposure is sufficiently stirred, and the thickness of the developer film remaining on the surface of the wafer W after rotation is equal to or greater than a predetermined thickness. To be determined.
[0046]
When the rotation is started, as shown in FIG. 10, the developer on the wafer W is shaken off, and the developer on the wafer W is stirred, so that the concentration of the developer on the wafer W surface is made uniform. It is done. Then, after the elapse of 2.0 seconds from the start of rotation, the rotation of the wafer W is stopped, and a thin film having a predetermined thickness, for example, 8 μm to 100 μm, is formed on the wafer W as shown in FIG. . Note that the thickness of the thin film is changed by the density of the exposure pattern.
[0047]
Thereafter, the development of the wafer W is performed for 48 seconds while the wafer W is stationary, and when the stationary development is completed, the development process of the wafer W is completed. Therefore, in this embodiment, the developer supplying process and the immediately subsequent static developing process are combined for 10 seconds, the subsequent rotating process is performed for 2 seconds, and the stationary developing process is performed again for 48 seconds. The development process has been performed.
[0048]
Thereafter, the cleaning nozzle 71 is moved to above the center of the wafer W, rotation of the wafer W is started at a predetermined speed, and a cleaning liquid is supplied from the cleaning nozzle 71 and the back surface cleaning nozzle 67 to the wafer W to clean the wafer W. Is done. At this time, the cup 65 is raised, and the cleaning liquid or the like scattered from the wafer W is received by the cup 65.
[0049]
When the supply of the cleaning liquid is stopped, the wafer W is rotated at a higher speed and the wafer W is dried. When this drying process of the wafer W is completed, the developing process for the wafer W is completed, and the wafer W is unloaded from the developing processing apparatus 18 by the main transfer apparatus 13.
[0050]
In the above embodiment, since the wafer W is rotated during the developing process of the wafer W and the developer is stirred, the uneven density of the developer caused by the so-called developer flow phenomenon described above is eliminated, and the wafer W surface. The development speed in the inside is made uniform. Therefore, development after the rotation of the wafer W is performed without unevenness, and variation in the line width of the circuit pattern in the wafer W surface is suppressed. Actually, in the experiment by the inventors, the line width variation of 3σ = 18 nm (in the 250 nm Line pattern) in the conventional method becomes 3σ = 8 nm in the present method, and the line width variation is improved. Is allowed.
[0051]
Further, since the thickness of the liquid film of the developer remaining on the wafer W after the rotation is set to a predetermined thickness, that is, 8 to 100 μm, the developer is dried and developed during the remaining development processing after the rotation. Is prevented from being suitably performed.
[0052]
Furthermore, the agitation step in the above embodiment is performed by rotating the wafer in one direction (forward rotation), but after such rotation, this time, it is rotated in the opposite direction (inversion) and further agitated. Also good. In this way, the developer concentration on the substrate is made more uniform by normal rotation and inversion.
[0053]
It should be noted that the rotation speed of the wafer when reversed after normal rotation is preferably faster than the rotation speed during fine weather. For example, when rotating in the normal rotation for 2 seconds at a speed of 100 rpm, the rotation speed is faster than that during reversal. For example, the wafer may be rotated at a speed of 250 rpm.
[0054]
Such rotation and reversal control of the spin chuck 60 is performed by the rotation controller 62. That is, first, when the spin chuck 60 rotates forward for a predetermined time, the spin chuck 60 is stopped. Next, the rotation control device 62 is programmed to control the rotation drive mechanism 61 so that the spin chuck 60 is reversely rotated at a speed higher than that during normal rotation for a predetermined time.
[0055]
Further, after stirring and shaking off the developer on the wafer W, the developer supply nozzle 70 is further moved from the other end of the wafer W to one end in the direction opposite to the direction of the arrow in FIG. You may make it supply a developing solution again with respect to the surface. As a result, the uniformity of the development process can be improved.
[0056]
In the above embodiment, the step of supplying the developer to the entire surface of the wafer W is performed by so-called nozzle scanning in which the developer supply nozzle 70 supplies the developer while moving from one end of the wafer W to the other end. However, the developer may be supplied to the rotated wafer W with the developer supply nozzle 70 stopped. In this case, for example, as shown in FIG. 12, the developer supply nozzle 70 is moved to above the center of the wafer W, and then the developer is discharged onto the wafer W rotated at a predetermined rotation speed, for example, 30 rpm. The developer is supplied to the entire W surface. Then, for example, the static development is performed for 9 sec as in the above embodiment, the wafer W is rotated (stirred) for 2.0 sec, and then the static development is again performed for 48 sec. The developing process for the wafer W is completed. By carrying out such a process, the development speed in the wafer W surface is made uniform as in the above-described embodiment, and a uniform line width is formed on the wafer W.
[0057]
Further, when the developing solution supply nozzle 70 is stopped or moved on the wafer W while the wafer W is rotating, the developing solution is supplied to the wafer W to develop the entire surface of the wafer W. You may make it supply a liquid.
[0058]
In this case, for example, the wafer W is rotated at a high speed, for example, 1000 rpm, and a position S (shown in FIG. 5) outside one end of the wafer W while the developer supply nozzle 70 discharges the developer on the wafer W. To the upper center of the wafer W. At this time, a thin film of the developer is formed on the wafer W. Then, the developer supply nozzle 70 stops above the center of the wafer W, and the rotation of the wafer W is reduced to, for example, 100 rpm while the developer is discharged. In this state, the developer is supplied onto the wafer W for a predetermined time, and a liquid film of the developer having a predetermined thickness, for example, 1 mm is formed. After that, when the discharge of the developer is stopped and the developer supply process is completed, the static development is performed, for example, for 5 seconds, and then the rotation (stirring) process of the wafer W is performed for 2.0 seconds. Finally, 48 seconds of static development is performed again, and the development processing of the wafer W is completed. By carrying out such a process, the developing speed in the wafer W plane is made uniform as in the above-described embodiment, and a line width having no variation is formed on the wafer W.
[0059]
In any case, after stirring and shaking off the developer on the wafer W, the wafer W is rotated in the direction opposite to the arrow direction in FIG. 12 and developed again from the developer supply nozzle 70 onto the surface of the wafer W. The liquid may be supplied. This further improves the uniformity of the development process.
[0060]
In each of the development processing methods in the above-described embodiments, the thickness of the developer film is measured after the developer stirring step, and the rotation time of the wafer W during the stirring step is changed based on the measurement result. You may make it do. In this case, for example, as shown in FIG. 13, a device such as a laser displacement meter 95 capable of measuring the thickness of the liquid film of the developer is provided above the spin chuck 60 in the development processing device 18. The measurement value measured by the laser displacement meter 95 is transmitted to the rotation control device 62 that controls the rotation of the spin chuck 60. Further, the rotation control device 62 stores a function for changing the setting of the rotation time to an appropriate one based on the transmitted measurement result, for example, an allowable value of the film thickness of the developer, and the measured film thickness. And a function for correcting the setting of the rotation time only when the measured value falls below the allowable value.
[0061]
Then, after the rotation of the wafer W is completed, the thickness of the developer film is measured, and the setting of the rotation time is changed based on the measured value. For example, when the film thickness of the developer is 5 μm or less, the rotation time is changed from 2.0 sec to 1.5 sec, for example, and by reducing the rotation time, the thickness of the developer liquid film is equal to or greater than a predetermined thickness. It is corrected to become. Thus, by measuring the thickness of the liquid film of the developer after rotation and changing the setting of the rotation time based on the measurement result, the thickness of the liquid film after rotation of the wafer W to be processed next can be reduced. For example, an adverse effect such as the fact that the developer is too thin to dry and the subsequent development is not suitably performed is prevented. Further, the rotation time may be changed so that the film thickness becomes thin even when the film thickness is too thick.
[0062]
Although the rotation time is changed based on the measurement result of the thickness of the developer film, the rotation speed or rotation acceleration of the wafer W may be changed. Further, all of the rotation time, the rotation speed, and the rotation acceleration may be changed, or any two of the parameters may be changed. Further, based on the measurement result, the developing time when developing the substrate by stopping the rotation driving member after the rotation of the substrate may be controlled.
[0063]
Although the embodiment described above has been described with respect to the developing method for the wafer W in the photolithography process of the semiconductor wafer device manufacturing process, the present invention is also applicable to a developing method for a substrate other than a semiconductor wafer, such as an LCD substrate. Can be applied.
[0064]
【The invention's effect】
According to the present invention, by stirring the developer on the substrate surface, the concentration of the developer on the substrate becomes uniform in the substrate surface, and the development speed in the substrate surface becomes the same. To be done. Therefore, the line width of the circuit pattern formed on the substrate is formed to a predetermined width, and the yield is improved.
[0065]
By agitating the developer by rotating the substrate, it is possible to easily carry out a development processing method including an agitation process using the function of an existing apparatus.
[0066]
In addition, by setting the thickness of the developer after the stirring step to a predetermined thickness or more, drying of the developer is prevented, and subsequent development is favorably performed, so that the yield is improved.
[Brief description of the drawings]
FIG. 1 is a plan view showing an external appearance of a coating and developing treatment system having a development processing device used in a development processing method according to an embodiment.
FIG. 2 is a front view of the coating and developing treatment system of FIG.
FIG. 3 is a rear view of the coating and developing treatment system of FIG. 1;
FIG. 4 is an explanatory view of a longitudinal section of a development processing apparatus used in the present embodiment.
FIG. 5 is an explanatory diagram of a transverse section of a development processing apparatus used in the present embodiment.
6 is a perspective view of a developer supply nozzle used in the development processing apparatus of FIG. 4. FIG.
7 is a longitudinal sectional view of the developer supply nozzle of FIG.
FIG. 8 is an explanatory diagram showing time distribution from the start of supply of developer to the end of development.
FIG. 9 is an explanatory diagram showing a state in which a developing solution is supplied onto the wafer and a liquid film of the developing solution is formed.
FIG. 10 is an explanatory diagram showing a state in which the wafer is rotated and the developer on the wafer is shaken off.
FIG. 11 is an explanatory diagram showing a state in which the rotation of the wafer is completed and a thin film is formed on the wafer.
FIG. 12 is a perspective view showing another supply mode in the developer supply step.
FIG. 13 is an explanatory view of a longitudinal section of a development processing apparatus when a laser displacement meter for measuring the film thickness of a developing solution is provided.
[Explanation of symbols]
1 Coating and developing treatment system
18 Development processing equipment
60 Spin chuck
70 Developer supply nozzle
86 Developer supply port
S Start position
E End position
W wafer

Claims (10)

A method of developing a substrate by supplying a developer to the substrate surface while the developer supplying means moves relative to the substrate,
A first step in which a developer is supplied to the substrate surface;
A second step in which the substrate is developed for a first predetermined time;
The second step includes a step of stopping the substrate for a second predetermined time after completion of the first step and performing static development, and after the second predetermined time has elapsed, the substrate is rotated to rotate the substrate surface. The step of stirring the developer to make the developer concentration uniform on the substrate, and then measuring the thickness of the developer film, and changing the time for rotating the substrate based on the measurement result And a developing process characterized by comprising the steps of : The second predetermined time is a time from when a developing solution is supplied onto a substrate to when a chemical reaction of development in an exposure portion proceeds by about 50% to 80%. Development processing method.   3. The development processing method according to claim 2, wherein the stirring step by the rotation is performed by rotating the substrate forward and then inverting it.   The development processing method according to claim 3, wherein the reversal is performed at a speed higher than a rotation speed during normal rotation.   5. The development process according to claim 2, wherein the rotation of the substrate is performed such that a thickness of the developer after the developer agitating step is equal to or greater than a predetermined thickness. Method. The first step is performed by supplying the developer to the substrate while the developer supply means moves from one end to the other end of the substrate. The development processing method according to any one of 5 . The first step is performed by supplying the developer to the substrate while the developer supply means is stopped above the substrate and the substrate is rotated. The development processing method according to any one of 1 to 6 . The first step is performed by supplying a developer to the substrate when the developer supply means is stopped or moving on the substrate while the substrate is rotating. The development processing method according to claim 1, wherein: An apparatus for developing a substrate by supplying a developer to the substrate surface while moving the developer supply means relative to the substrate,
A rotation drive member for holding and rotating the substrate;
A rotation control device for reversing the rotation drive member after supplying the developer;
A measuring device for measuring the thickness of the developer supplied to the substrate surface;
A development processing apparatus, comprising: a control device that controls a rotation time of the substrate based on a measurement result by the measurement device. The control device according to claim 9, further comprising: a control device that controls a developing time when developing the substrate by stopping the rotation driving member after the rotation of the substrate based on a measurement result by the measuring device. Development processing equipment.

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