JP6521126B2 - Development device - Google Patents

Description

  The present invention relates to a technology for performing development processing by supplying a developer to a substrate on which a resist film has been formed after exposure.

  In a photolithography process in a manufacturing process of a semiconductor device, a resist film is formed, and a development process of supplying a developing solution is performed on a substrate exposed along a predetermined pattern to form a resist pattern. As one of the development processing methods, using a nozzle provided with a long discharge port, the nozzle is moved from one end of the substrate to the other end while discharging the developer from the discharge port, and the developer is spread over the entire substrate There is something that pours and forms a paddle. In the present developing method, since the developer can be poured while the substrate is kept stationary, it is referred to as a stationary developing method here. Patent Document 1 describes an example of this static developing system.

  As another development processing method, there is a method of moving the nozzle while rotating the substrate and moving the supply position of the developing solution in the radial direction of the rotating substrate. A liquid film of the developer is formed on the surface of the substrate by the movement of the supply position of the developer and the action of the centrifugal force, and the developer constituting the liquid film flows. Here, this developing method is called a rotational developing method. Patent Document 2 describes an example of this rotational development system.

  As a substrate developed by development processing, there is, for example, a circular semiconductor wafer (hereinafter referred to as a wafer). There are various types of resist films formed on the wafer, for example, a thick film resist formed when processing a film to be processed having a small selection ratio at the time of etching, or EUV (Extreme There are a resist film for ultraviolet (extreme ultraviolet) exposure, a resist film for ArF exposure and a KrF exposure.

  Among them, in the case of a resist film with particularly low sensitivity, it is necessary to lengthen the contact time with the developer, but in the case of the static development system described above, the dissolved component dissolved in the developer As a result, the concentration of the developer decreases, and as a result, the reactivity of the developer decreases, and the time required for development processing becomes longer. Further, also in the case of processing a resist film with low sensitivity in the rotational development method, the time for development processing and the consumption amount of the developer increase. Therefore, more efficient development methods are needed.

Patent No. 3614769: Paragraphs 0044, 0058 to 0059, FIGS. Patent No. 4893799: Paragraph 0026, Figure 8

  The present invention has been made under such circumstances, and an object thereof is to provide a developing method capable of efficiently developing a resist film after exposure, a developing device, and a storage medium storing the developing method. To provide.

The developing device of the present invention comprises: a substrate holding portion for horizontally holding a circular substrate on which a resist film after exposure is formed;
A substrate rotation unit configured to rotate the substrate about a vertical axis;
A first developing solution supply hole formed in a linear shape shorter than the radius of the substrate held by the substrate holding portion, and supplying a developing solution to the substrate held by the substrate holding portion; And a second developer supply hole for supplying the developer to the substrate, and a second developer supply hole for supplying the developer to the substrate. And a gas supply hole disposed between the first developer supply hole and the second developer supply hole for supplying a gas for sweeping the developer supplied to the substrate, the first developer The supply hole is disposed to face the surface of the substrate held by the substrate holding portion so that the supply hole is located on the front side in the moving direction relative to the rotation direction of the substrate with respect to the second developer supply hole. The nozzle head and
A nozzle drive unit for moving the nozzle head unit from the center side to the peripheral side of the substrate;
With the substrate rotated, the nozzle head portion is located at the central portion of the substrate while supplying the developer from the first and second developer supply holes and supplying the gas from the gas supply holes. Moving the nozzle head from the side to the peripheral edge, moving the nozzle head after the nozzle head reaches the peripheral edge of the substrate, supplying the developer from the first developer supply hole, and The steps of stopping the supply of gas from the gas supply holes and then stopping the supply of the developer from the second developer supply holes and the rotation of the substrate after a predetermined time has elapsed are performed. And a control unit that outputs a control signal .

The developing device may have the following configuration.
(A) The gas supply hole is provided so as to discharge gas obliquely downward in a direction in which the second developer supply hole is disposed .
(B) In the step of moving the nozzle head from the central side to the peripheral side of the substrate, moving the nozzle heads in opposite directions to each other.

  According to the present invention, the developer in the developer film supplied to the surface of the substrate on which the resist film after exposure is formed is flushed to thin the developer film, and then a new developer is supplied. It is possible to perform an efficient development process using a highly reactive developer film, instead of the developer film with low reactivity, which contains components dissolved in the developer film from the resist film.

FIG. 2 is a longitudinal side view of a developing device according to an embodiment of the invention. FIG. 2 is a plan view of the developing device. It is a longitudinal cross-sectional view of the nozzle head part provided in the said developing device. It is a top view which shows an example of the developing solution supply surface of the pad nozzle provided in the said nozzle head part. It is a top view which shows the other example of the said developing solution supply surface. FIG. 6 is a first explanatory view of a developing process performed by the developing device. It is 2nd explanatory drawing of the said development process. It is 3rd explanatory drawing of the said development process. It is a time chart concerning the above-mentioned development processing. It is a schematic diagram which shows the effect | action of the said pad nozzle. It is a top view which shows the modification of the said developing device. It is 1st explanatory drawing of the image development process which concerns on the said modification. It is 2nd explanatory view of development processing concerning the modification. It is a time chart of development processing concerning the modification. It is a top view of the image development device concerning a 2nd embodiment. It is a perspective view of the slit nozzle part which concerns on the said 2nd Embodiment. It is 1st explanatory drawing of the image development processing which concerns on the said 2nd Embodiment. It is 2nd explanatory drawing of the image development processing which concerns on the said 2nd Embodiment. It is a time chart of development processing concerning the 2nd embodiment. It is a schematic diagram which shows the effect | action of the slit nozzle part which concerns on the said 2nd Embodiment. It is an explanatory view showing a modification of a development device concerning a 2nd embodiment. It is 1st explanatory drawing of the image development process which concerns on the said 3rd Embodiment. It is 2nd explanatory drawing of the image development processing which concerns on the said 3rd Embodiment. It is 3rd explanatory drawing of the image development processing which concerns on the said 3rd Embodiment. It is 4th explanatory drawing of the image development processing which concerns on the said 3rd Embodiment. It is a time chart of development processing concerning the 3rd embodiment. It is a schematic diagram which shows the effect | action of the image development process which concerns on the said 3rd Embodiment. It is 1st explanatory drawing which shows the result of a preliminary | backup experiment. It is 2nd explanatory drawing which shows the result of a preliminary | backup experiment.

First Embodiment
The configuration of the developing device 1 according to the first embodiment of the present invention will be described based on FIGS. 1 to 5. In the developing device 1, a resist film is formed on the surface, and the wafer W after the resist film is exposed in a predetermined pattern is transported and processed. As shown in FIGS. 1 and 2, the developing apparatus 1 includes a spin chuck 11 which is a substrate holding unit, and the spin chuck 11 holds the wafer W horizontally by adsorbing to the central portion of the back surface of the wafer W. . In addition, the spin chuck 11 is connected to a rotation drive unit 13 provided below via a rotation shaft 12. The spin chuck 11, the rotation shaft 12, and the rotation drive unit 13 correspond to a substrate rotation unit for rotating the wafer W around the vertical axis.

  In the developing device 1, a cup 2 is provided to surround the wafer W held by the spin chuck 11. The cup body 2 includes an outer cup 21 and an inner cup 22. The upper side of the cup body 2 is open. The outer cup 21 has a rectangular shape on the upper side and a cylindrical shape on the lower side. A stepped portion 23 is provided on the lower side of the outer cup 21, and an elevation unit 24 for moving the outer cup 21 up and down is connected to the stepped portion 23. The inner cup 22 is cylindrical, and its upper side is inclined inward. When the outer cup 21 ascends, the inner cup 22 is pushed up by the lower end surface contacting the step 23. As a result, when removing the developing solution from the wafer W, as shown by a broken line in FIG. 1, the cup body 2 (outer cup 21 and inner cup 22) is lifted to receive the liquid scattered from the wafer W. Can.

  A circular plate 25 is provided on the lower side of the wafer W held by the spin chuck 11, and a ring-shaped guide member 26 having a mountain-shaped vertical cross section is provided on the outer side of the circular plate 25. The guide member 26 guides the developing solution and the cleaning solution spilled from the wafer W to the liquid receiving portion 27 which is an annular recess provided on the outside of the circular plate 25. A drain pipe 28 for discharging the gas and liquid in the liquid receiving portion 27 is connected to the bottom surface of the liquid receiving portion 27, and a gas-liquid separator (not shown) provided on the downstream side of the drain pipe 28 is connected. Gas-liquid separation is performed. The drainage after gas-liquid separation is collected in a drainage tank (not shown).

  Below the wafer W held by the spin chuck 11, a pin 14 connected to the elevating mechanism 15 is disposed. The pin 14 moves up and down between a position above the holding surface of the wafer W by the spin chuck 11 and a position below the wafer W, and transfers the wafer W between the substrate transfer mechanism (not shown) and the spin chuck 11. Run.

  The developing device 1 supplies a developing solution to the wafer W to form a liquid reservoir 30 (see FIGS. 6 to 8 and 10 described later) which is a liquid film (developer film) of the developing solution. And a cleaning solution nozzle 45 for supplying pure water, which is a cleaning solution, to the wafer W after development processing. As shown in FIG. 2, the pad nozzle 31 is provided at the distal end portion of the arm 41, while the nozzle drive unit 42 is connected to the proximal end side of the arm 41. The nozzle drive unit 42 has a function of moving the arm 41 up and down and a function of moving along the guide rail 43 extending horizontally, and moves the pad nozzle 31 along the radial direction of the wafer W held by the spin chuck 11 It can be done. Further, on the outer side of the cup body 2, there is provided a standby area 44 composed of a nozzle bus provided with a drainage port and configured to be freely engageable with the tip of the pad nozzle 31.

The cleaning solution nozzle 45 is provided at the distal end of the arm 47, and the nozzle drive unit 48 is connected to the proximal end side of the arm 47. The nozzle drive unit 48 has a function of moving the arm 47 up and down, and a function of moving along the guide rail 49 extending horizontally. The nozzle driving unit 48 can move the cleaning nozzle 45 between the upper position of the wafer W held by the spin chuck 11 and the standby area 40 formed of a nozzle bus provided outside the cup body 2. .
Further, as shown in FIG. 1, the cleaning solution nozzle 45 is connected to a cleaning solution supply source 46 provided with a pump, a valve and the like.

  In the developing device 1 having the configuration described above, the pad nozzle 31 has a function of suppressing the decrease in the reactivity of the developer due to the influence of the dissolved component dissolved from the resist film. Hereinafter, the configuration of the nozzle head 3 provided with the pad nozzle 31 will be described with reference to FIGS. 3 to 5.

  As shown in FIG. 3, the nozzle head unit 3 is disposed to face the wafer W held by the spin chuck 11 and has a pad nozzle 31 provided with a developer supply surface 310 in which a large number of developer supply holes 314 are formed. A nozzle rotation mechanism 38 for rotating the pad nozzle 31 about a vertical axis, and a manifold portion 37 in which a flow path through which a developing solution or the like supplied to the pad nozzle 31 flows is formed.

  The pad nozzle 31 has a structure in which a developer supply plate 312 in which a hollow portion 313 is formed is provided on the lower surface side of a disk-shaped member smaller than the diameter of the wafer W (for example, 300 mm). A large number of developing solution supply holes 314 are formed on the lower surface side of the developing solution supply plate 312, and the developing solution flowing into the hollow portion 313 through the developing solution supply path 311 formed in the center of the pad nozzle 31. The developer is uniformly supplied toward the lower side of the developer supply surface 310 through the developer supply holes 314.

  Further, in the region along the upper surface, the side peripheral surface and the lower surface (the bonding surface with the developer supply plate 312) of the pad nozzle 31, the reaction contained in the liquid reservoir 30 of the developer supplied from the developer supply surface 310. A nitrogen gas flow path 315 is formed to supply a gas (nitrogen gas in this example) which flushes out the developer with reduced properties. The nitrogen gas passage 315 on the lower surface side of the pad nozzle 31 penetrates the hollow portion 313 of the developer supply plate 312 and is in communication with the nitrogen gas supply hole 316 opened in the developer supply surface 310.

The nitrogen gas supply hole 316 protrudes below the lower surface of the developer supply surface 310 where the developer supply hole 314 is opened, and the area where the developer supply hole 314 is formed is the periphery of the developer supply surface 310. It opens in the lower surface of the projected part 317 arranged to divide into a plurality of areas along the direction.
For example, as shown in FIG. 4, the protruding portion 317 a may be formed so as to radially and linearly extend from the center of the circular developing solution supply surface 310. In this case, the formation area of the developer supply hole 314 is divided into a fan along the circumferential direction of the developer supply surface 310. Further, as shown in FIG. 5, the protruding portion 317 b may be formed to extend in a curvilinear manner from a center of the developing solution supply surface 310 so as to spirally spiral. In this case, the formation region of the developer supply hole 314 is divided into a fan-shape curved along the circumferential direction of the developer supply surface 310. For the convenience of description, the arrangement of the ridges 317a and 317b in FIGS. 4 and 5 shows a state where the pad nozzle 31 is viewed from the upper surface side and the developing solution supply surface 310 is seen through.

  On the other hand, a cylindrical rotation cylinder 383 is connected to the upper surface side central portion of the pad nozzle 31. The rotary cylinder 383 has a structure in which a lower rotary cylinder 383b connected to the pad nozzle 31 and an upper rotary cylinder 383a having a smaller diameter than the lower rotary cylinder 383b and a long dimension in the vertical direction are coaxially connected. ing. The inside of the rotary cylinder 383 is hollow, and the hollow communicates with the developing solution supply path 311 of the pad nozzle 31. Further, a nitrogen gas flow passage 384 communicating with the nitrogen gas flow passage 315 on the side of the pad nozzle 31 is formed in the cylinder wall constituting the lower rotary cylinder 383 b. The nitrogen gas channel 384 opens toward the cavity of the rotary cylinder 383 at its upstream end.

The nozzle rotation mechanism 38 includes an electric motor mechanism (not shown), and rotates the pad nozzle 31 connected to the rotation cylinder 383 around a vertical axis, using the rotation cylinder 383 as a rotor. The upper rotating cylinder 383a is inserted into the nozzle rotating mechanism 38, and the rotating cylinder 383 is rotatably held around vertical axes by bearings 381, 382.
The nozzle rotation mechanism 38 and the rotation cylinder 383 correspond to the nozzle rotation unit of this example.

  A manifold portion 37 is connected to the nozzle rotation mechanism 38 via a flange portion 376. In the manifold portion 37, flow paths 372, 371 having a double-pipe structure of an inner internal flow path 372 through which the developer flows and an outer external flow path 371 through which the nitrogen gas flows are formed. From the lower surface of the manifold portion 37, these flow paths 372 and 371 form a double pipe portion 377 and protrude downward, and the double pipe portion 377 is in the cavity of the rotating cylinder 383 held by the nozzle rotating mechanism 38. Is inserted in the

  The internal flow path 372 is opened at the lower end portion of the double pipe portion 377 and is in communication with the developing solution supply path 311 of the pad nozzle 31 via the hollow of the rotary cylinder 383. On the other hand, the outer flow path 371 is a side circumference of the lower side of the double pipe portion 377 so as to supply nitrogen gas toward the position facing the opening of the nitrogen gas flow path 384 formed in the lower rotary cylinder 383b. It is open to the surface. A gap between the inner peripheral surface of the rotating cylinder 383 and the outer peripheral surface of the double pipe portion 377 is partitioned by the seal portions 374 and 375, and the developer supplied from the inner flow path 372 and the supply from the outer flow path 371 It is designed not to mix with the nitrogen gas. The inner peripheral surface of the rotary cylinder 383 is partitioned through the sliding surfaces of the seal portions 374 and 375 in such a manner that a region through which a developer or nitrogen gas flows can be partitioned.

The upstream end of the internal flow path 372 formed in the manifold portion 37 is connected to a developer supply source 300A including a pump, a valve, and the like through a developer supply path 391. Further, the upstream end of the external flow passage 371 is connected to the nitrogen gas supply source 300 B via the nitrogen gas supply passage 392.
In the developing device 1 of this embodiment, the wafer W and the nozzle head portion 3 are relative to each other by the nozzle rotating unit including the nozzle driving unit 42 described above, the substrate rotating unit including the spin chuck 11 and the like, and the nozzle rotating mechanism 38 The moving mechanism to be moved is configured.

  The developing device 1 is provided with a control unit 10 comprising a computer. The control unit 10 has a program storage unit (not shown). The program storage unit stores a program in which steps are configured to execute a developing process described later in the operation. The control unit 10 outputs a control signal to each part of the developing device 1 based on this program, and the movement of the pad nozzle 31 and the cleaning liquid nozzle 45 by the nozzle drive parts 42 and 48, the rotation of the pad nozzle 31 by the rotation mechanism 38, the developer Supply source 300A, pad nozzle 31 from cleaning liquid supply source 46, supply of developing solution and cleaning liquid to cleaning liquid nozzle 45, supply of nitrogen gas to pad nozzle 31 from nitrogen gas supply source 300B, wafer W by spin chuck 11 Each operation such as rotation and lifting and lowering of the pin 14 is controlled. The program storage unit is configured as a storage medium such as a hard disk, a compact disk, a magnet optical disk, or a memory card, for example.

  Here, various design variables relating to the pad nozzle 31 provided in the above-described developing device 1 may be exemplified. The horizontal moving speed of the pad nozzle 31 moving above the wafer W held by the spin chuck 11 Is, for example, 10 mm / sec to 100 mm / sec. The diameter of the developer supply surface 310 is, for example, 50 mm to 200 mm. The rotational speed (the number of rotations per unit time) of the wafer W is preferably 100 rpm or less, more preferably 10 rpm to 50 rpm, in order to prevent the liquid from splashing when the developer is discharged onto the wafer W. Further, the rotational speed of the pad nozzle 31 is adjusted, for example, in the range of 50 rpm to 1000 rpm.

  Subsequently, the procedure of the developing process and the cleaning process performed using the above-described developing device 1 will be described with reference to FIGS. 6 to 10. Here, FIG. 9 is a time chart of the development processing. In this time chart, the relationship between the elapsed time (processing time) from the start of the development processing, the rotational speed of the pad nozzle 31 and the rotational speed of the wafer W is shown. The solid line graph shows the rotational speed of the pad nozzle 31 (indicated as “case 1”), and the dashed line graph shows the rotational speed of the wafer W, respectively. Further, in this time chart, a band chart indicates a period in which the developer and the nitrogen gas are discharged from the pad nozzle 31 and a period in which the pad nozzle 31 is moving while discharging the developer.

  First, when the wafer W is transferred into the developing device 1 by the substrate transfer mechanism (not shown) and held by the spin chuck 11, the pad nozzle 31 moves from the standby area 44 to a position above the central portion of the wafer W. Then, as schematically shown in FIG. 10, the pad nozzle 31 is lowered such that the developing solution supply surface 310 is disposed several mm above the upper surface of the wafer W. Subsequently, the developer is supplied from the pad nozzle 31 to the wafer W, and the pad nozzle 31 is rotated counterclockwise as viewed from the top side (time t1 in FIG. 9). A liquid reservoir 30 larger than the developing solution supply surface 310 is formed between the wafer W and the developing solution supply surface 310 so as to be in contact with the wafer W.

  When the pad nozzle 31 reaches a predetermined rotational speed, the rotational speed is maintained, and then the wafer W is rotated clockwise as viewed from above (FIG. 6). When the rotational speed of the wafer W reaches, for example, 10 rpm, with the rotational speed maintained, the central portion of the wafer W (the pad nozzle moving period in FIG. The movement of the pad nozzle 31 is started from the mark "" to the peripheral part (indicated by "E" in the same band chart) (time t2 in FIG. 9). Thus, the liquid reservoir 30 is spread toward the peripheral portion of the wafer W in a state of being in contact with the developing solution supply surface 310 of the pad nozzle 31 (FIG. 7).

  When the liquid pool 30 is expanded, the developing solution in the liquid pool 30 is agitated by rotating the pad nozzle 31, and the concentration of the developing solution containing the components dissolved in the developing solution from the resist film is uniformed. . As a result, the uniformity of the CD (Critical Dimension) of the pattern developed from the exposed resist film can be enhanced. The rotational direction of the pad nozzle 31 is not limited to the case of rotating counterclockwise as viewed from the upper surface side, and may rotate clockwise as the wafer W. However, as shown in FIG. 7, by rotating the wafer W and the pad nozzle 31 in opposite directions, the force for stirring the developer is increased, and the effect of further improving the uniformity of the developer concentration can be obtained. .

  Then, the supply of nitrogen gas is started from the nitrogen gas supply hole 316 while continuing the rotation of the pad nozzle 31 at time t3 after a predetermined time, for example, 1 to 2 seconds, has elapsed since the start of the movement of the pad nozzle 31. . As described with reference to FIGS. 4 and 5, the formation region of the developer supply hole 314 is divided in the circumferential direction of the developer supply surface 310 by the ridge portion 317 in which the nitrogen gas supply hole 316 is formed. . FIG. 10 schematically shows a liquid reservoir 30 formed on the lower side of the region where the developer supply holes 314 are formed and the region where the nitrogen gas supply holes 316 are formed (projections 317). As described above, the pad nozzle 31 and the wafer W are respectively rotated, but in FIG. 10, the relative moving direction of the pad nozzle 31 and the wafer W is indicated by the arrow.

  Here, in FIGS. 4 and 5, the forming direction of the developer supply holes 314 and the forming region (protrusions of the nitrogen gas supply holes 316) of the nitrogen gas supply holes 316 are alternately arranged along the rotational direction of the pad nozzle 31. The symbols (A) to (E) are attached. It is considered that the schematic view shown in FIG. 10 shows the state of the liquid reservoir 30 formed on the lower side of these regions (A) to (E). At this time, in the regions (A), (C), and (E), which are the formation regions of the developer supply holes 314, a liquid reservoir 30 of the developer filling the gap between the developer supply surface 310 and the wafer W is formed. Be done. On the other hand, on the lower side of the formation region of the nitrogen gas supply hole 316, the developer is pushed away by the nitrogen gas discharged downward from the nitrogen gas supply hole 316 to form the gas phase portion 301, and the liquid reservoir 30 A thin film portion 302 is formed, which is a region where the developer film forming the thin film becomes thin.

At this time, in consideration of the relative movement direction of the pad nozzle 31 and the wafer W, for example, the point (a) on the wafer W shown in FIG. At point (a), liquid pool 30 in region (A) → thin film portion 302 in region (B) → liquid reservoir 30 in region (C) → thin film portion 302 in region (D) → liquid in region (E) The reservoirs 30 → ..., the liquid reservoirs 30 and the thin film portion 302 alternately pass through.
As described above, the pad nozzle 31 moves from the central portion side to the peripheral portion side of the wafer W while rotating, and since the wafer W itself is also rotated around the vertical axis, the point (a) The number of times that the liquid reservoir 30 and the thin film portion 302 pass alternately changes depending on the moving speed of the pad nozzle 31 and the rotation speed of the wafer W.

  The progress of the development processing when the formation region of the developer supply hole 314 and the formation region of the nitrogen gas supply hole 316 alternately pass as described above will be described. For example, when the point (a) on the wafer W contacts the liquid reservoir 30 of the developer supplied from the developer supply hole 314 of the area (A), the resist film is partially developed corresponding to the exposed pattern. Dissolve in liquid. The reactivity of the developer decreases as the resist film dissolves.

  When the nitrogen gas supply hole 316 in the region (B) moves to the place where the reactivity of the developer decreases in this way, the components dissolved from the resist film by the nitrogen gas discharged from the nitrogen gas supply hole 316 are removed. The developer solution contained is swept away to form the thin film portion 302. The overflowed developer flows, for example, along the extending direction of the ridges 317 and is discharged to the outer region of the gas phase portion 301.

  When the region (C) reaches the portion where the thin film portion 302 is formed and a new developer is supplied from the developer supply hole 314, the ratio of the developer containing the component dissolved from the resist film becomes small. The developing process at point (a) proceeds with a highly reactive developer.

  Thus, by alternately executing the supply of a new developer and the washout of the developer with reduced reactivity, the reactivity of the developer contacting point (a) can be made high when viewed on time average. It is possible to maintain and shorten the time required for development processing. As a result, even when developing a thick film resist with low sensitivity or a resist film for EUV, it is possible to suppress an increase in time required for the development processing.

  From the viewpoint described above, it can be said that the nitrogen gas supply hole 316 corresponds to a push-out mechanism for pushing and thinning the liquid reservoir 30 (developer film). Further, the region where the developing solution supply hole 314 located on the front side in the relative moving direction of the pad nozzle 31 and the wafer W is the first development, with the protruding portion 317 formed with the nitrogen gas supply hole 316 interposed therebetween. The formation region of the developer supply hole 314 corresponding to the liquid supply unit and located on the rear side in the moving direction corresponds to the second developer supply unit. Therefore, in the relationship between the regions (A) and (C) in FIG. 10, the region (A) functions as a first developer supply unit and the region (C) functions as a second developer supply unit. Further, in the relationship between the regions (C) and (E) in FIG. 10, the region (C) functions as a first developer supply unit, and the region (E) functions as a second developer supply unit.

  In addition to the nitrogen gas described above, the gas used to flush the liquid reservoir 30 may be argon gas, which has a small reactivity with the developer and the resist film. However, if the influence on the developer and the resist film is small, it is natural that clean air may be used.

  The pad nozzle 31 continues moving on the wafer W while rotating so as not to overtake the spreading liquid reservoir 30. The reason for avoiding overtaking of the liquid pool 30 by the pad nozzle 31 is that when the overtaking is performed, the developing solution runs out and the plurality of liquid pools 30 individually spread over the surface of the wafer W. When the interfaces of these broken liquid reservoirs 30 are combined, there is a possibility that the CD of the resist pattern at the relevant position may be different from the CD of the resist pattern at other locations under the influence. As a result, since the CDU (Critical Dimension Uniformity) indicating the in-plane uniformity of the resist pattern is lowered, the moving speed of the pad nozzle 31 is set to such an extent that overtaking of the liquid pool 30 does not occur.

  When the pad nozzle 31 moves to the peripheral portion side of the wafer W and the entire surface of the wafer W is covered with the liquid reservoir 30 of the developing solution, the movement of the pad nozzle 31 and the supply of the developing solution are stopped (FIGS. Time t4). Here, the entire surface of the wafer W means the entire formation region of the resist pattern, and for example, in the wafer W in which the formation region is not provided in the peripheral portion of the wafer W, the liquid reservoir 30 is formed in the peripheral portion. It does not have to be. Although FIG. 8 shows an example in which the liquid reservoir 30 is formed slightly inside the peripheral edge of the wafer W, the peripheral edge of the wafer W may be covered with the liquid reservoir 30.

  The pad nozzle 31 continues to rotate and stirs the developing solution until the entire surface of the wafer W is covered with the liquid reservoir 30 as described above. Then, after stopping the movement of the pad nozzle 31 and the supply of the developing solution, the rotation of the pad nozzle 31 and the rotation of the wafer W are stopped, and the supply of nitrogen gas from the nitrogen gas supply hole 316 is stopped (FIG. 9). Time t5). Thereafter, the pad nozzle 31 is raised to move the pad nozzle 31 to the standby area 44.

  The surface of the wafer W after retracting the pad nozzle 31 is covered by the stationary liquid reservoir 30, and the reaction between the resist film and the developer further progresses on the entire surface of the wafer W (not shown). When the predetermined time has elapsed, the cleaning solution nozzle 45 is moved to a position above the central portion of the wafer W, and the wafer W is rotated at a predetermined rotational speed. Then, the cleaning liquid is supplied from the cleaning liquid nozzle 45 to the wafer W, and the cleaning liquid is spread over the entire surface of the wafer W by the centrifugal force acting on the cleaning liquid to remove the liquid reservoir 30 of the developer from the wafer W (not shown). Then, the discharge of the cleaning liquid from the cleaning liquid nozzle 45 is stopped, and when the rotation of the wafer W is continued, the cleaning liquid is shaken off and the wafer W is dried. After that, the wafer W is unloaded from the developing device 1 by a substrate transfer mechanism (not shown).

  The developing device 1 according to the present embodiment has the following effects. The developer in the reservoir 30 is sprayed with nitrogen gas from a nitrogen gas supply hole 316 onto the reservoir 30 (developer film) of the developer supplied on the surface of the wafer W on which the resist film after exposure is formed. To form a thin film portion 302. By supplying a new developing solution to the area where the thin film portion 302 is formed, the developing solution having high reactivity is changed to a developing solution with reduced reactivity including a component dissolved in the developing solution film from the resist film. A film can be formed, and efficient development can be performed when viewed in time average.

  Here, as illustrated in Case 1 of FIG. 9, there is no restriction that the rotational speed of the pad nozzle 31 must be constant during the movement from the central portion side to the peripheral portion side of the wafer W. For example, as indicated by a broken line in FIG. 9 as “case 2”, control may be performed to gradually increase the rotational speed as the pad nozzle 31 moves from the central portion of the wafer W toward the peripheral portion. As in the example described with reference to FIGS. 6 to 8, when the liquid pool 30 is spread from the central portion side to the peripheral portion side of the wafer W, the contact time between the surface of the wafer W and the developing solution is the wafer W It becomes short as it goes to the peripheral part side of.

  Therefore, in case 2 of FIG. 9, as the pad nozzle 31 moves toward the peripheral portion side, the rotation speed becomes higher to accelerate the stirring of the developer, and further, the liquid reservoir 30 and the thin film portion 302 Are alternately formed to increase the reactivity between the developer and the resist. By controlling the rotational speed of the pad nozzle 31 in this manner, the uniformity of the CD within the surface of the wafer W is made higher while improving the efficiency of the development processing.

  However, in the present invention, it is not an essential requirement to rotate the pad nozzle 31 about the vertical axis. For example, even when the pad nozzle 31 is not rotated, the pad nozzle 31 provided with the developing solution supply hole 314 and the nitrogen gas supply hole 316 while rotating the wafer W on the spin chuck 11 is the central portion of the wafer W. By moving from the side to the peripheral edge side, the liquid reservoir 30 and the thin film portion 302 described with reference to FIG. 10 can be formed. As a result, after the developing solution containing the dissolved component is washed away, an action and an effect of advancing a developing process by supplying a new developing solution having high reactivity are obtained.

  In the first embodiment, the wafer W is rotated in order to spread the liquid reservoir 30 from the central portion to the peripheral portion of the wafer W, but the rotation of the wafer W is not an essential requirement. For example, the developing solution supply surface 310 of the pad nozzle 31 is formed to be equal to or larger than the wafer W, and the developing solution supply surface 310 is brought close to the wafer W. Then, the developer and the nitrogen gas are supplied from the formation region of the developer supply hole 314 and the formation region of the nitrogen gas supply hole 316 on the developer supply surface 310, and the pad nozzle 31 is rotated. At this time, lateral movement of the pad nozzle 31 is not performed. As a result, on the lower surface of the developer supply surface 310, the developer is stirred to form the liquid reservoir 30 and spread from the central portion of the wafer W toward the peripheral portion, and each position on the surface of the wafer W 30 and the thin film portion 302 pass alternately. Therefore, also in this example, it is possible to perform development processing with high in-plane uniformity of the CD while improving the processing efficiency.

  By the way, when the pad nozzle 31 is rotated, the liquid flow is also generated in the region slightly outside the developer supply surface 310 along the liquid flow below the developer supply surface 310. Therefore, in the case of forming a swirling flow without rotating the wafer W and moving the pad nozzle 31 in the lateral direction as described above, the size of the developer supply surface 310 of the pad nozzle 31 is determined by the size of the wafer W. It may be slightly smaller.

  Here, the substrate on which the above-described development processing is performed is not limited to the circular wafer W, and a square substrate may be processed. In the above example, the liquid reservoir 30 formed on the wafer W is limited to the developing solution, but the cleaning process may be performed by applying a cleaning liquid to the wafer W using the pad nozzle 31.

  Furthermore, the moving direction of the pad nozzle 31 is not limited to the case of moving from the central portion side of the wafer W toward the peripheral portion side. In contrast to the above-described example, the pad nozzle 31 may be moved from the peripheral edge side of the wafer W to the central portion side. In this case, the liquid reservoir 30 spreads from the peripheral portion side to the central portion side of the wafer W. However, when the developing solutions merge at the central portion of the wafer W and different interfaces contact each other, As described above, the CD uniformity may be reduced. Therefore, the pad nozzle 31 from the peripheral portion side to the central portion side may be employed in a development process or the like in which high CD uniformity is not required.

Subsequently, FIG. 11 shows a developing device 1a provided with two sets of nozzle heads 3 (nozzle heads 3A and 3B). The nozzle head units 3A and 3B have the same structure as the nozzle head unit 3 shown in FIG. 3, and the pad nozzles 31 (hereinafter referred to as the first pad nozzle 31A and the second pad nozzle 31B for convenience, respectively) Have a). The nozzle heads 3A and 3B are connected to the nozzle drive unit 42 through the arm 41, and move along the guide rails 43 between the upper position of the wafer W held by the spin chuck 11 and the standby area 44. What can be done is the same as in the case of the developing device 1 shown in FIG. Thus, the rotation, the discharge of the developing solution, and the movement operation on the wafer W can be performed independently by each pad nozzle 31.
Hereinafter, in each of the embodiments described with reference to FIGS. 11 to 25, the same components as those described with reference to FIGS. 1 to 10 are denoted by the same reference numerals as those used in these drawings. It is

  The developing process using the developing device 1 a will be described with reference to FIGS. 12 to 14. Here, the configuration of the time chart in FIG. 14 is substantially the same as the example described in FIG. 9, but the supply timings of the developer and nitrogen gas from each of the first pad nozzle 31A and the second pad nozzle 31B. Is different from the example shown in FIG. Further, changes in the rotational speed of the first pad nozzle 31A are indicated by a solid line, and changes in the rotational speed of the second pad nozzle 31B are indicated by a two-dot chain line.

  First, the first pad nozzle 31A is moved to a position above the central portion of the stationary wafer W, and lowered to a predetermined height position, and then the developer is supplied to the wafer W from the first pad nozzle 31A. The point of rotating the first pad nozzle 31A counterclockwise as viewed from the upper surface side is the same as the case of the pad nozzle 31 shown in FIG. 6, so that separate illustration is omitted (time t1 in FIG. 14). Then, wafer W is rotated, and when it reaches a predetermined rotational speed, movement of first pad nozzle 31A toward the peripheral portion side of wafer W is started, and after a predetermined time has elapsed from the start of the movement, the nitrogen gas supply hole 316 The supply of nitrogen gas is started (time t2 in FIG. 14).

  Thus, as shown in FIG. 12, the wafer W at a timing when the first pad nozzle 31A reaches a predetermined position while spreading the liquid reservoir 30 of the developing solution from the central portion side to the peripheral portion side of the wafer W. The second pad nozzle 31B is advanced to a position where the distance from the central portion is substantially the same between the first pad nozzle 31A and the second pad nozzle 31B, with the central portion interposed therebetween. Also in the second pad nozzle 31B, rotation of the second pad nozzle 31B, supply of the developer from the developer supply hole 314, supply of nitrogen gas from the nitrogen gas supply hole 316 are sequentially started, and The second pad nozzle 31B is moved in a direction opposite to that of the pad nozzle 31A (time t3 in FIG. 14).

Thus, the first and second pad nozzles 31A and 31B are moved from the central portion side of the wafer W toward the peripheral portion side, and both the pad nozzles 31A and 31B reach the peripheral portion and the liquid pool 30 on the entire surface of the wafer W Is formed, the movement of each pad nozzle 31A, 31B is stopped (time t4 in FIG. 13, FIG. 14). Thereafter, rotation stop of both the pad nozzles 31A and 31B and the wafer W and supply stop of the developer and nitrogen gas from the pad nozzles 31A and 31B are executed (time t5 in FIG. 14).
After stopping the discharge of the developer from both pad nozzles 31A and 31B, the reaction of the resist film is advanced by the liquid reservoir 30 of the developer as in the example described with reference to FIG. The rotation of the wafer W and the supply of the cleaning liquid are performed to remove the developer from the wafer W.

  Even when the two pad nozzles 31A and 31B move on the wafer W, the developer is discharged in the region where the developer supply holes 314 are formed in each developer supply surface 310, and the region where the nitrogen gas supply holes 316 are formed. Nitrogen gas is discharged. As a result, as shown in FIG. 10, the liquid reservoir 30 and the thin film portion 302 alternately pass through the surface of the wafer W to be processed to realize efficient development processing, as shown in FIGS. It is the same as the developing device 1 shown.

  In the developing device 1a according to the present embodiment using two pad nozzles 31A and 31B, development processing using the first pad nozzle 31A is performed on the central portion of the wafer W, and the first pad nozzle is a wafer After moving from a central portion of W to a predetermined position near the peripheral portion, development processing is performed using two pad nozzles 31A and 31B up to the peripheral portion. In each pad nozzle 31A, 31B, the development processing described with reference to FIG. 10 is repeatedly performed, and the number of times that the liquid reservoirs 30 and the thin film portion 302 alternately pass through the surface of the wafer W is increased. Thus, uniform development processing can be performed.

As a result, the uniformity of the CD of the resist pattern in the surface of the wafer W can be more reliably improved while shortening the processing time. In particular, as the size of the wafer W increases, the amount of components dissolved in the liquid pool 30 increases on the peripheral edge side of the wafer W where the processing area is wide, and the reactivity of the developer may be easily reduced. Because of this, a method of performing development processing using a plurality of pad nozzles 31A and 31B as described above is effective.
Here, as shown in the case 2 of FIG. 9, the rotational speed of the pad nozzles 31A and 31B increases in the one side or both sides of the pad nozzles 31A and 31B as the pad nozzles 31A and 31B become closer to the peripheral portion. Control may be performed.

Second Embodiment
The developing device 1b according to the second embodiment described with reference to FIGS. 15 to 20 is a slit nozzle which is a nozzle head portion provided with a plurality of developer supply slits 318a and 318b which is a slit-shaped developer supply hole. The development according to the first embodiment in which a large number of developing solution supply holes 314 are formed on the developing solution supply surface 310 of the rotating pad nozzle 31 in that the portion 31C is fixedly provided at the tip of the arm 41. Different from device 1.

  As shown in FIGS. 15 and 16, the slit nozzle portion 31C of this example is fixed to the tip end portion of the arm 41 with the main body of the slit nozzle portion 31C having a rectangular parallelepiped shape elongated in the left-right direction when viewed from the arm 41 side. It is provided. The width of the slit nozzle portion 31C in the left and right direction is shorter than the radius of the wafer W to be processed, and two developer supply slits 318a and 318b formed linearly in the left and right direction are formed on the bottom They are disposed substantially parallel and spaced apart forward and backward. Further, at the position of the bottom surface of the slit nozzle portion 31C, which is sandwiched between the developer supply slits 318a and 318b which are disposed apart from each other, a gas supply linearly extending substantially parallel to the developer supply slits 318a and 318b is provided. A nitrogen gas supply slit 316a which is a hole is provided.

  As shown by a broken line in FIG. 16, the inside of the main body of the slit nozzle portion 31C is partitioned corresponding to the slits 318a, 318b, and 316a. The developer is supplied from the developer supply source 300A described above to the developer supply slits 318a and 318b via the developer supply paths 391a and 391b, and the nitrogen gas supply source 300B via the nitrogen gas supply path 392 Nitrogen gas is supplied to the nitrogen gas supply slit 316a. Accordingly, in the present embodiment, the first developer supply slit 318a corresponds to a first developer supply unit, and the second developer supply slit 318b corresponds to a second developer supply unit. Further, the nitrogen gas supply slit 316a corresponds to a gas supply unit.

As shown in FIG. 16, the developer supply slits 318a and 318b project downward from the bottom surface of the slit nozzle portion 31C, and develop downward in the direction orthogonal to the wafer W held by the spin chuck 11. Eject fluid. On the other hand, the nitrogen gas supply slit 316a discharges nitrogen gas obliquely downward toward the rear side where the second developer supply slit 318b is disposed. Further, the nitrogen gas supply slit 316a is disposed at a position near the first developer supply slit 318a between the developer supply slits 318a and 318b which are provided separately from each other in the front and rear direction.
Here, the direction in which the nitrogen gas supply slit 316a discharges nitrogen gas is not limited to the case where discharge is directed diagonally backward, and, similarly to the developer supply slits 318a and 318b, the direction in which the nitrogen gas supply slit 316a discharges nitrogen gas is downward. The nitrogen gas may be discharged toward the side.

As shown in FIG. 15, the arm 41 holds the slit nozzle portion 31C at a position where it can pass above the central portion of the wafer W held by the spin chuck 11. In addition, the slits 318a, 318b, and 316a formed in the slit nozzle portion 31C extend in the direction along the moving direction of the slit nozzle portion 31C.
In the developing device 1b of this embodiment, a moving mechanism for relatively moving the wafer W and the nozzle head unit 3 is configured by the substrate rotating unit including the nozzle driving unit 42 and the spin chuck 11 described above.

  The developing process of the wafer W using the slit nozzle portion 31C described above will be described with reference to FIGS. 17 to 20. FIG. In the time chart of FIG. 19, a band chart is shown for the supply periods of the developer and nitrogen gas from the developer supply slits 381a and 381b, the nitrogen gas supply slit 316a, and the movement period of the slit nozzle portion 31C. Further, in the present example, the graph of the rotational speed shows only the rotational speed of the wafer W.

  First, the slit nozzle portion 31C is moved to the upper position of the central portion of the stationary wafer W and lowered to a predetermined height position, and then the rotation of the wafer W is started, and toward the peripheral portion side of the wafer W The movement of the slit nozzle portion 31C is started (time t1 in FIG. 19). Then, at time t2 when the wafer W reaches a predetermined rotation speed, supply of the developer from the first developer supply slit 318a and supply of nitrogen gas from the nitrogen gas supply slit 316a are started. At this time, the timing for starting supply of the developing solution is before the one end on the central portion side of the wafer W in the first developing solution supply slit 318a moves from the position covering the upper side of the center of the wafer W. It is preferable to start the supply of the developer. Thus, the liquid reservoir 30 of the developing solution can be formed in the central portion of the wafer W.

  When discharging the developing solution onto the rotating wafer W from the first developing solution supply slit 318a, the first developing solution supply slit 318a is disposed so as to extend in the radial direction of the wafer W as shown in FIG. There is. For this reason, the discharge area of the developing solution formed corresponding to the shape of the first developing solution supply slit 318a is linearly extended in the direction intersecting the relative moving direction of the wafer W with respect to the slit nozzle portion 31C. Is formed. Further, the discharge area (gas discharge area) of nitrogen gas formed corresponding to the shape of the nitrogen gas supply slit 316a is also linear in the direction intersecting the relative moving direction of the slit nozzle portion 31C and the wafer W. It will be formed to extend.

  Then, the developer and nitrogen gas are supplied from the first developer supply slit 318a and the nitrogen gas supply slit 316a, and after a predetermined time has elapsed since the supply of the developer and nitrogen gas is started, the developer is supplied from the second developer supply slit 318b. Supply is started (time t3 in FIG. 19). The developer discharge area formed corresponding to the shape of the second developer supply slit 318b is also formed to extend linearly in the direction intersecting the relative movement direction of the wafer W with respect to the slit nozzle portion 31C. Ru.

  Therefore, as shown in FIG. 20, on the lower side of the slit nozzle portion 31C, the relative movement direction (FIG. 20) is located below the first developer supply slit 318a and the second developer supply slit 318b. Two developer discharge areas are formed in the direction intersecting with the arrow in the drawing), and the areas become the liquid reservoir 30 of the developer. On the other hand, in the nitrogen gas discharge area to which nitrogen gas supplied from the nitrogen gas supply slit 316a disposed between the first developer supply slit 318a and the second developer supply slit 318b is sprayed, the developer is swept away. As a result, a gas phase portion 301 is generated, and a thin film portion 302 which is a region in which the developer film constituting the liquid reservoir 30 becomes thinner is formed.

  At this time, for example, focusing on the point (a) on the wafer W shown in FIG. 20, the point (a) corresponds to the liquid reservoir 30 in the developer discharge area of the first developer supply slit 318a → nitrogen gas supply slit The thin film portion 302 in the nitrogen gas discharge area 316a passes through the liquid reservoir 30 in the developer discharge area of the second developer supply slit 318b. As a result, similar to the operation of the pad nozzle 31 described with reference to FIG. 10, when the supply of a new developer and the washout of the developer with reduced reactivity are alternately performed and viewed on a time average ( a) The reactivity of the developing solution in contact with the point can be maintained high, and the time required for the development processing can be shortened.

Thus, the slit nozzle portion 31C is located on the peripheral portion side of the wafer W while supplying the developing solution from the first developing solution supply slit 318a and the second developing solution supply slit 318b and supplying the nitrogen gas from the nitrogen gas supply slit 316a. When the entire surface of the wafer W is covered with the liquid reservoir 30 of the developing solution, the movement of the slit nozzle portion 31C, and the developing solution from the first developing solution supply slit 318a and the nitrogen gas supply slit 316a. , Supply of nitrogen gas is stopped (time t4 in FIG. 18 and FIG. 19). Next, after a predetermined time has elapsed, the discharge of the developer from the second developer supply slit 318b is stopped at the timing when the rotation of the wafer W is stopped (time t5 in FIG. 19).
After stopping the supply of the developing solution from the slit nozzle portion 31C, the reaction of the resist film is advanced by the liquid reservoir 30 of the developing solution in the same manner as the example described with reference to FIG. The developer is removed from the wafer W by executing the rotation of W and the supply of the cleaning liquid.

  The present embodiment is not limited to the case where only one slit nozzle portion 31C is provided as in the developing device 1b shown in FIG. For example, the wafer W may be processed by providing two sets of slit nozzle portions 31C as in the developing device 1a shown in FIG.

  Further, it is not essential to perform processing while moving the slit nozzle portion 31C by the arm 41. For example, a slit nozzle portion 31C including a first developer supply slit 318a, a second developer supply slit 318b, and a nitrogen gas supply slit 316a whose width in the left-right direction is longer than the radius of the wafer W is provided. The slit nozzle portion 31C may be disposed such that the radius of the wafer W is covered by the nozzles 318b and 316a. When developer and nitrogen gas are supplied from the slits 318a, 318b, and 316a while the wafer W is rotated, the developer reservoir 30 is accumulated on the entire surface of the wafer W while exerting the same function as the example shown in FIG. Can be formed.

  Further, as shown in FIG. 21, a slit including a first developer supply slit 318a, a second developer supply slit 318b, and a nitrogen gas supply slit 316a having a length covering an area from one end to the other end of the wafer W. While the nozzle portion 31D is provided and the wafer W is stopped, the slit nozzle portion 31D is moved from one end side to the other end side of the wafer W by a nozzle driving mechanism (moving mechanism) (not shown) to hold the liquid reservoir 30 of the developer. You may form.

  In the case of using the slits 318a, 318b, and 316a in the method of forming the developing solution discharge area and the nitrogen gas discharge area extending linearly in the direction intersecting the relative movement direction of the wafer W in the slit nozzle portions 31C and 31D. It is not limited to. For example, a plurality of supply holes are linearly arranged in the cross direction, and the developer and the nitrogen gas are simultaneously supplied from the plurality of supply holes, whereby the developer discharge area extending in a linear shape, nitrogen A gas discharge area may be formed.

  Furthermore, the method of forming the nitrogen gas discharge area between the plurality of developer discharge areas is the first developer supply slit 318a formed one by one, like the slit nozzle portion 31C shown in FIG. The configuration is not limited to the configuration in which one nitrogen gas supply slit 316a is disposed between the two developer supply slits 318b. A plurality of nitrogen gas supply slits 316a may be disposed between the plurality of first developer supply slits 318a and the plurality of second developer supply slits 318b. In addition to these, for example, the width in the front-rear direction of the slit nozzle portion 31C is further expanded, and a nitrogen gas supply slit and a developer supply slit are provided in front of the first developer supply slit 318a and behind the second developer supply slit 318b. You may provide additionally the set of.

Third Embodiment
In the development processing according to the third embodiment, for example, using the developing device 1a provided with two pad nozzles 31A and 31B shown in FIG. 11, the relative movement operation of these pad nozzles 31A and 31B is used. The liquid reservoir 30 of the developer and the thin film portion 302 are formed. The configuration of the developing device 1a is the same as that shown in FIG.

  The developing process of this embodiment will be described with reference to FIGS. 22 to 27. In this embodiment, as shown in FIG. 22, the second pad nozzle 31B is moved to a position above the central portion of the wafer W, The nozzle 31A is moved to a position (denoted by "M" in the band chart of FIG. 26) slightly out of the central position.

Then, the wafer W and both pad nozzles 31A and 31B are rotated and the supply of the developing solution from the developing solution supply hole 314 is started from the second pad nozzle 31B toward the central portion of the wafer W (see FIGS. 22 and 26). Time t1). In parallel with these operations, the second pad nozzle 31 B moves from the central portion to the peripheral portion side of the wafer W, and the first pad nozzle 31 A deviates slightly to the side from the central position described above It moves in the same direction as the second pad nozzle 31 B from the above position. At this time, the moving speed of the second pad nozzle 31 B is controlled to be slower than the moving speed of the first pad nozzles 31 A.

  Then, the supply of the developing solution from the first pad nozzle 31A is started at the timing when the first pad nozzle 31A moves to a position near the central portion of the wafer W (time t2 in FIGS. 23 and 26). Here, if the developer is supplied while moving the second pad nozzle 31B, the developer on the central portion side of the liquid pool 30a is on the peripheral edge side under the influence of inertia acting on the liquid pool 30a spreading the surface of the wafer W. The thin film portion 302, which is a region where the developer film becomes thin, is formed on the central portion side as shown in FIG.

  When the developing solution is supplied from the first pad nozzle 31A at a position upstream of the second pad nozzle 31B in the moving direction, a new developing solution is supplied to the thin film portion 302 to form a liquid reservoir 30b. As a result, focusing on the point (a) on the wafer W, the point (a) is formed as the liquid pool 30a formed by the second pad nozzle 31B moves from the second pad nozzle 31B. The thin film portion 302 passes through the liquid reservoir 30b formed by the first pad nozzle 31A. Therefore, similar to the operation of the pad nozzle 31 described with reference to FIG. 10, supply of a new developer and discharge of a developer with reduced reactivity are alternately performed and viewed on time average (a The reactivity of the developing solution in contact with the points can be maintained high, and the time required for the development processing can be shortened.

  Thus, the supply of the developer from the second pad nozzle 31B and the supply of the developer from the first pad nozzle 31A at the upstream position in the moving direction of the second pad nozzle 31B are performed, and the second pad is produced. When the nozzle 31B reaches the peripheral portion of the wafer W, the rotation of the second pad nozzle 31B and the supply of the developing solution are stopped (time t3 in FIGS. 24 and 26). Then, the second pad nozzle 31 B is retracted to the standby area 44.

Even during this period, the first pad nozzle 31A continues the supply of the developing solution while moving toward the peripheral portion of the wafer W, following the movement path of the second pad nozzle 31B. When the first pad nozzle 31A reaches the peripheral portion of the wafer W, the rotation of the first pad nozzle 31A and the supply of the developing solution are stopped (time t4 in FIGS. 25 and 26). As a result, the entire surface of the wafer W is covered with the developer reservoir 30b.
After stopping the supply of the developing solution from the second pad nozzle 31B, the reaction of the resist film is advanced by the liquid reservoir 30 of the developing solution as in the example described with reference to FIG. The rotation of the wafer W and the supply of the cleaning liquid are performed to remove the developer from the wafer W.

In the above-described development process, the second pad nozzle 31B corresponds to a first developer supply unit, and the first pad nozzle 31A corresponds to a second developer supply unit. The two nozzle drive units 42 shown in FIG. 11 correspond to the first supply position adjustment unit and the second supply position adjustment unit for adjusting the supply position of the developing solution from the respective pad nozzles 31B and 31A. doing.
Furthermore, it is not essential that the moving speed of the first pad nozzle 31A be slower than the moving speed of the second pad nozzle 31B, and the moving speeds of both the bad nozzles 31A and 31B may be the same. In this case, it is preferable to start the movement of the first pad nozzle 31A behind the second pad nozzle 31B at a timing when the first pad nozzle 31A can not catch up with the second pad nozzle 31B.

  As described above, in the development processing method described with reference to FIGS. 22 to 27, the relative movement between the second pad nozzle 31B and the first pad nozzle 31A is used to pool the entire surface of the wafer W. 30a.fwdarw.thin film portion 302.fwdarw.liquid reservoir 30b to perform efficient development. For this reason, for example, the thin film portion 302 is formed between the two second pad nozzles 31B and the first pad nozzle 31A even if the nitrogen gas is not supplied from the nitrogen gas supply holes 316 of the pad nozzle 31 shown in FIG. Be done.

  Therefore, providing the nitrogen gas supply hole 316 in the pad nozzle 31 is not essential. For example, the developing solution supply passage 311 formed in the pad nozzle 31 shown in FIG. 3 is opened toward the lower surface of the developing solution supply surface 310, and the developing solution supply passage 311 is formed in the gap between the developing solution supply surface 310 and the wafer W. The nozzle head portion 3 configured to agitate the developing solution by rotating the pad nozzle 31 while spreading the developing solution supplied from the above may be adopted. Note that, by utilizing the pad nozzles 31 provided with the nitrogen gas supply holes 316, supply of new developing solution in the lower region of each pad nozzle 31A, 31B and formation of the thin film portion 302 are repeated, and development processing is more effectively performed. Of course, you can do

Furthermore, in the development processing method described with reference to FIGS. 22 to 27, the slit nozzle portion 31C shown in FIG. 16 or the like may be used, or a straight nozzle in which the lower end of the developer supply pipe is opened. It may be used.
Further, it is not essential to form the liquid reservoir 30b by supplying the developing solution while moving the first pad nozzle 31A by following the movement path of the second pad nozzle 31B. For example, the developing solution may be supplied by stopping at the central portion of the wafer W, which is the position on the upstream side in the moving direction of the second pad nozzle 31B.

(Experiment)
As shown in FIG. 3, the developer solution is supplied using the pad nozzle 31 which is held by the nozzle head 3 in a rotatable state around the vertical axis and the developer supply passage 311 opens directly to the lower surface of the pad nozzle 31. The relationship between the timing and rotation time for rotating the pad nozzle 31 and the CD of the pattern formed on the lower side of the pad nozzle 31 was examined. The developer supply hole 314 and the nitrogen gas supply hole 316 are not formed in the developer supply surface 310 of the pad nozzle 31.
A. Experimental conditions
(Reference Example 1-1) The developer was supplied for a total of 60 seconds using the pad nozzle 31 having a diameter of 10 cm, and the pad nozzle 31 was rotated only for the latter 20 seconds.
(Reference Example 1-2) The pad nozzle 31 was rotated only for 20 seconds in the middle of the developing solution supply period for 60 seconds.
Reference Example 1-3 The pad nozzle 31 was rotated only for the first 20 seconds of the developing solution supply period of 60 seconds.
(Reference Example 1-4) During the developing solution supply period of 60 seconds, the operation of rotating the pad nozzle 31 for 5 seconds and then stopping the rotation of the pad nozzle 31 for 10 seconds was repeated four times.
(Reference Example 1-5) A developer for 50 seconds was supplied, and the rotation operation of the pad nozzle 31 was continued during that period.
(Reference Example 1-6) The pad nozzle 31 was rotated for the first one second of the developing solution supply period of 60 seconds.
(Reference Example 1-7) The pad nozzle 31 was rotated for the first 5 seconds of the developing solution supply period of 60 seconds.
Comparative Example 1-1 The developer was supplied for 50 seconds, and the pad nozzle 31 was not rotated during that period.

B. Experimental Results FIG. 28 shows the experimental results for Reference Examples 1-1 to 1-5 and Comparative Example 1-1, and FIG. 29 is the experiment for Reference Examples 1-1, 1-3, and 1-6 to 1-7. Show the results. In each graph, the height of the bar graph indicates the CD [nm] of the developed pattern, and the smaller the value of the CD, the more advanced the development process.

  According to the experimental results shown in FIG. 28, while the developing process proceeds as the rotation time of the pad nozzle 31 is made longer (Reference Example 1-5), when the rotation time of the pad nozzle 31 is equalized, the development is performed. It can be seen that as the rotation is performed at a timing closer to the start of liquid supply, the development processing proceeds (Reference Examples 1-1 to 1-3). Further, as shown in FIG. 29, even when the rotation time of the pad nozzle 31 is short, the rotation of the pad nozzle 31 is longer in the latter half of the developer supply period if the rotation is performed immediately after the start of the developer supply start. The effect of advancing the development processing is higher than in the case where the reaction is performed (Reference Examples 1-6, 1-7, 1-1).

  The operation of rotating the pad nozzle 31 has an effect of stirring the liquid reservoir 30 of the developing solution formed between the developing solution supply surface 310 and the wafer W to make the concentration of the developing solution uniform. At this time, the fact that the effect of advancing the development process is higher if stirring is performed immediately after the supply of the developing solution is that, near the interface between the developing solution and the resist film, the dissolved component immediately after the developing solution contacts the resist film. It shows that the influence of the decrease in reactivity appears due to the influence of Therefore, after forming the liquid reservoir 30 of the developing solution as in the present invention, the developing solution is immediately flushed to form the thin film portion 302, and then a new developing solution is supplied to suppress the decrease in reactivity and develop processing. It can be seen that the effect of advancing the

W Wafer 1, 1a, 1b
Development device 11 Spin chucks 3, 3A, 3B
Nozzle head 30, 30b
Liquid pool 302 Thin film portion 31, Pad nozzle 31C, 31D
Slit nozzle section 310 developer supply surface 316 nitrogen gas supply hole 316a nitrogen gas supply slit 318a first developer supply slit 318b second developer supply slit 38 nozzle rotation mechanism 383 rotating cylinder

Claims (3)

A substrate holding portion for horizontally holding a circular substrate on which a resist film after exposure is formed;
A substrate rotation unit configured to rotate the substrate about a vertical axis;
A first developing solution supply hole formed in a linear shape shorter than the radius of the substrate held by the substrate holding portion, and supplying a developing solution to the substrate held by the substrate holding portion; And a second developer supply hole for supplying the developer to the substrate, and a second developer supply hole for supplying the developer to the substrate. And a gas supply hole disposed between the first developer supply hole and the second developer supply hole for supplying a gas for sweeping the developer supplied to the substrate, the first developer The supply hole is disposed to face the surface of the substrate held by the substrate holding portion so that the supply hole is located on the front side in the moving direction relative to the rotation direction of the substrate with respect to the second developer supply hole. The nozzle head and
A nozzle drive unit for moving the nozzle head unit from the center side to the peripheral side of the substrate;
With the substrate rotated, the nozzle head portion is located at the central portion of the substrate while supplying the developer from the first and second developer supply holes and supplying the gas from the gas supply holes. Moving the nozzle head from the side to the peripheral edge, moving the nozzle head after the nozzle head reaches the peripheral edge of the substrate, supplying the developer from the first developer supply hole, and The steps of stopping the supply of gas from the gas supply holes and then stopping the supply of the developer from the second developer supply holes and the rotation of the substrate after a predetermined time has elapsed are performed. And a control unit for outputting a control signal . The developing device according to claim 1, wherein the gas supply hole is provided to discharge gas obliquely downward in a direction in which the second developer supply hole is disposed. In the step of moving the nozzle head from the central side to the peripheral side of the substrate, the nozzle heads are moved in opposite directions to each other in the step of moving the nozzle head from the central side to the peripheral side. 2. The developing device according to 2.

Images