JP2005175079A - Device and method for coating and developing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To contribute to countermeasures for flooding on the exposure device side in a coating and development device for processing substrates, applied by liquid immersion exposure. <P>SOLUTION: The coating and development device is provided with a resist-coating unit for coating a resist on the surface of a substrate, and a developing unit for developing the substrate after the substrate is exposed, in a state where a liquid layer is formed on the surface of the substrate and a water-repellent member is arranged at its periphery. The substrate is held by a substrate holder for holding the substrate horizontally; and while the substrate after coating of resist is turned, a coating liquid is supplied thereto, to form a water-repellent film, which covers the periphery of a rear surface side of the substrate via a side end surface from at least the periphery of the front surface side thereof. In this case, a liquid forming the liquid layer can be restrained from dropping from the outer periphery of the substrate. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a coating / developing apparatus and a coating / developing method for coating a resist on a surface of a substrate and developing the substrate after immersion exposure.

  Conventionally, in the photoresist process, which is one of the semiconductor manufacturing processes, a resist is applied to the surface of a semiconductor wafer (hereinafter referred to as a wafer), the resist is exposed in a predetermined pattern, and then developed to form a resist pattern. doing. Such processing is generally performed using a system in which an exposure apparatus is connected to a coating / developing apparatus that performs resist coating / development.

  Incidentally, in recent years, device patterns have been increasingly miniaturized and thinned, and with this trend, there has been a growing demand for higher exposure resolution. Therefore, in order to increase the exposure resolution, development of exposure technology using EUVL, EUV or F2 is being promoted, while immersion exposure to improve the resolution by further improving the existing exposure technology using existing light sources such as ArF and KrF is being studied. Yes. In the semiconductor and manufacturing equipment industry, there is a strong movement to extend the life of ArF exposure equipment as much as possible for financial reasons, using ArF up to 45 nm, and showing that EUV will be postponed further Some are. Immersion exposure is a technique that allows light to pass through, for example, ultrapure water, and uses the feature that the wavelength of ArF at 193 nm is substantially 134 nm in water because the wavelength is shorter in water.

  An exposure apparatus that performs this immersion exposure will be briefly described with reference to FIG. First, the exposure unit 1 is arranged so as to face the surface of the wafer W held in a horizontal posture by a holding mechanism (not shown). A lens 10 is provided at the tip of the exposure means 1, and light emitted from an ArF light source (not shown) that has passed through the pattern mask passes through the lens 10 and is applied to the resist applied to the surface of the wafer W. Thus, the circuit pattern of the resist is transferred. In addition, a supply port 11 and a suction port 12 for passing light, for example, ultrapure water, are provided at the tip, and water is supplied between the lens 10 and the surface of the wafer W through the supply port 11. Further, the water is sucked and collected through the suction port. As a result, a water film that transmits light is formed in the gap between the lens 10 and the surface of the wafer W, and the light emitted from the lens 10 passes through the water film and is irradiated onto the resist. When a predetermined pattern is transferred to the surface of the wafer W, for example, as shown in FIG. 13, the wafer W is moved in the horizontal direction with a water film stretched between the wafer W and the exposure means 1 is moved. The pattern is sequentially transferred by irradiating light facing the position corresponding to the next transfer region 100.

  However, in the above-described immersion exposure, when the peripheral area of the wafer W is exposed, if the projected area of the water film protrudes outside the wafer W, the behavior of water that transmits light becomes unstable, for example, water spills out. Therefore, for example, there is a concern that the peripheral portion corresponding to the transfer region 101 in FIG. 13 cannot be exposed. Therefore, a device formation region cannot be secured at the peripheral edge of the wafer W, and the yield of the wafer W may be reduced.

  As one means for solving this problem, as shown in FIG. 14A, for example, a liquid receiving ring made of a water-repellent member having the same surface height as that of the wafer W, for preventing water from spilling down. It has been studied to perform exposure by arranging 13 to surround the outer periphery of the wafer W. Further, as shown in FIG. 14B, a concave stage 14 in which a dug portion in which the wafer W is accommodated is considered. However, even when the liquid receiving ring 13 or the concave stage 14 is used, there is a concern that water may spill from a slight gap between the outer periphery of the wafer W as shown in FIG. In particular, in the case of the liquid receiving ring 13, the wafer W whose surface is made of silicon or a silicon oxide film is hydrophilic to water, so that water is attracted by the surface tension through a gap with the outer peripheral edge of the wafer W. There is a problem that the spilled over and the periphery of the stage of the exposure apparatus will be flooded. Since the inside of the exposure apparatus is maintained at a constant temperature and humidity, if it is submerged, the humidity may increase and the electrical system may be short-circuited. For this reason, the immersion in the exposure apparatus must be avoided.

  As another problem, for example, when an amine-based resist is used, the resist generally has hydrophilicity. Therefore, when a water film is formed on the surface of the resist during immersion exposure, the resist Water may permeate into the surface or surface layer portion. Therefore, there is a concern that the dissolved resist component contaminates the lens 10 and, as a result, the pattern accuracy decreases. Also, although the resist for ArF is generally water-repellent, there is no water permeation at all, and there is a concern about the same problem.

  The present invention has been made based on such circumstances, and the object thereof is a coating / development apparatus for processing a substrate to which immersion exposure is applied, which is capable of forming a liquid film optimal for exposure. It is possible to ensure the surface state and contribute to the countermeasure against water immersion on the exposure apparatus side. As a result, it is an object of the present invention to provide a coating / developing apparatus and method that can increase the utilization rate of the substrate by exposing the periphery of the substrate. Another object is to form a highly accurate resist pattern on the surface of the substrate while preventing the resist component from adhering to the exposure means.

The coating / developing apparatus of the present invention is a coating / developing apparatus including a resist coating unit for coating a resist on the surface of a substrate and a developing unit for developing a substrate after exposure.
A substrate holding part for horizontally holding the substrate;
A rotation drive unit that rotates the substrate holding unit around a vertical axis;
A coating liquid for forming a water-repellent film is supplied to the substrate while rotating the substrate after resist coating while being held by the substrate holding unit, and the back surface from at least the peripheral portion on the surface side of the substrate through the side end surface A coating liquid supply unit that forms a water-repellent film across the peripheral edge of the side,
The developing unit develops the substrate after exposure in a state where a liquid layer that transmits light is formed on the surface of the substrate on which the water-repellent film is formed.

  Here, the water repellency of the “water repellent film” means that the contact angle of the liquid forming the liquid layer with respect to the surface of the water repellent film is 90 to 100 ° or more. Further, when the water repellent member is provided so as to surround the periphery of the substrate, it has the predetermined contact angle or, for example, when the gap between the substrate and the water repellent member is set to 0.5 mm, It means the case where the liquid forming the liquid layer does not spill out.

  The coating liquid supply unit may be provided in a resist coating unit, and the substrate holding unit may also serve as a substrate holding unit used when applying a resist to a substrate. The coating liquid supply unit includes an upper nozzle that supplies the coating liquid to the peripheral portion on the front surface side of the substrate held by the substrate holding unit, a lower nozzle that supplies the coating liquid to the peripheral portion on the back surface side of the substrate, In this case, a U-shaped member that is horizontally movable between a position where the peripheral edge of the substrate is inserted into the space and a position where the peripheral edge of the substrate is separated from the space, An upper nozzle that opens into the space in the U-shaped member and exhausts air to the opposite side to the center side of the substrate, and supplies the coating liquid to the peripheral portion on the surface side of the substrate, and the substrate The lower nozzle for supplying the coating liquid to the peripheral portion on the back surface side of this may be provided on the U-shaped member.

  Moreover, the structure provided with the means for removing the resist of the peripheral part in which the water-repellent film on the substrate surface is formed may be sufficient. Further, the substrate is provided with a peripheral exposure portion that exposes the peripheral portion of the substrate, and the resist-coated substrate is exposed at the peripheral exposure portion, and then the resist on the peripheral portion is removed by the developer. There may be. Furthermore, the coating liquid supply unit includes an upper nozzle that supplies the coating liquid to the central portion on the front surface side of the substrate held by the substrate holding unit, and a lower nozzle that supplies the coating liquid to the peripheral portion on the back surface side of the substrate. And a water repellent film may be formed on the entire surface of the substrate.

The resist pattern forming method of the present invention includes a step of applying a resist to the surface of a substrate,
Next, while the substrate is held horizontally on the substrate holding part, the coating liquid is supplied to the substrate while rotating the substrate holding part, and from at least the peripheral part on the front side of the substrate to the peripheral part on the back side through the side end face. Forming a straddling water repellent film;
Thereafter, a step of exposing the surface of the substrate with a liquid layer formed on the surface of the substrate;
And developing the exposed substrate.

  The step of applying the resist to the substrate is performed in a state where the substrate is held horizontally by the substrate holding portion, and the step of forming the water repellent film is performed while the substrate is held by the substrate holding portion. May be. The step of forming the water repellent film may be a step of supplying the coating liquid to the peripheral portion on the front surface side of the substrate and supplying the coating liquid to the peripheral portion on the back surface side. Further, after the step of applying the resist, before the step of forming the water-repellent film, a step of removing the peripheral resist on the surface of the substrate where the water-repellent film is formed may be performed. Furthermore, the step of supplying the coating liquid from the surface side of the substrate may be a step of supplying the coating liquid to the central portion of the substrate and supplying the coating liquid to the entire surface of the substrate.

  According to the present invention, since the water-repellent film is formed to extend from at least the front surface side peripheral portion of the substrate coated with the resist to the back surface side peripheral portion via the side end surface, the liquid is applied to the surface of the substrate. When immersion exposure is performed by forming a layer, the liquid forming the liquid layer is prevented from spilling from the outer peripheral edge of the substrate, which can contribute to prevention of immersion in the exposure apparatus. As a result, a semiconductor device that forms an integrated circuit by being exposed to the vicinity of the outer peripheral edge of the substrate can be manufactured, so that the utilization factor of the substrate can be increased. Further, for example, even when the water-repellent member is disposed so as to surround the substrate and the outer periphery, the liquid can be prevented from spilling from the gap between the outer periphery of the substrate and the inner periphery of the water-repellent member.

  Further, according to the present invention, by forming a water-repellent film on the entire surface of the resist applied to the surface of the substrate, for example, even when a hydrophilic resist is used, a liquid layer is formed on the surface of the substrate. When the immersion exposure is performed with the liquid formed, it is possible to prevent the liquid forming the liquid layer from penetrating into the resist and to prevent the components eluting from the resist from adhering to the lens of the exposure means, for example Or very little. As a result, a highly accurate resist pattern can be obtained. Also, when the substrate is moved laterally relative to the exposure means in order to change the transfer region, the liquid is less likely to be pulled by the water repellent film due to surface tension, so the liquid layer has good behavior. It is possible to suppress a reduction in exposure resolution due to fluctuations in the image.

  An overall configuration of a system in which an exposure apparatus is connected to a coating / developing apparatus according to an embodiment of the present invention will be briefly described with reference to FIGS. In the figure, B1 is a carrier mounting part for carrying in and out a carrier 2 in which, for example, 13 wafers W are hermetically stored, and a carrier station having a mounting part 20a on which a plurality of carriers 2 can be placed side by side. 20, an opening / closing part 21 provided on a wall surface in front of the carrier station 20, and a delivery means A 1 for taking out the wafer W from the carrier 2 through the opening / closing part 21.

  A processing unit B2 surrounded by a casing 22 is connected to the back side of the cassette mounting unit B1, and the processing unit B2 is a shelf unit in which heating / cooling system units are sequentially arranged from the front side. Main transfer means A2 and A3 for transferring the wafer W between the units U1, U2 and U3 and the liquid processing units U4 and U5 are alternately arranged. The main transport means A2 and A3 include one surface portion on the shelf unit U1, U2 and U3 side arranged in the front-rear direction as viewed from the carrier placement portion B1, and one surface on the right liquid processing unit U4 and U5 side which will be described later. It is placed in a space surrounded by a partition wall 23 composed of a part and a back part forming one surface on the left side. In the figure, reference numerals 24 and 25 denote temperature / humidity adjusting units including a temperature adjusting device for the treatment liquid used in each unit, a duct for adjusting the temperature and humidity, and the like.

  For example, as shown in FIG. 2, the liquid processing units U4 and U5 are arranged on a chemical solution storage unit 26 such as a resist solution and a developer, on a coating unit (COT) 30, a water repellent film unit (TC) described later, DEV) 27, hydrophobizing units BARC, and the like are stacked in a plurality of stages, for example, five stages. In addition, the above-described shelf units U1, U2, and U3 are configured such that various units for performing pre-processing and post-processing of the processing performed in the liquid processing units U4 and U5 are stacked in a plurality of stages, for example, 10 stages. The combination includes a heating unit for heating (baking) the wafer W, a cooling unit for cooling the wafer W, and the like.

  An exposure unit B4 is connected to the back side of the shelf unit U3 in the processing unit B2 through an interface unit B3 including, for example, a first transfer chamber 28a and a second transfer chamber 28b. In addition to two transfer means A4 and A5 for transferring the wafer W between the processing unit B2 and the exposure unit B4, a shelf unit U6 and a buffer carrier C0 are provided inside the interface unit B3. The shelf unit U6 is assigned with a transfer unit, a peripheral exposure unit 29 for selectively exposing only the peripheral portion of the wafer W, and the like.

  An example of the flow of wafers in this apparatus is as follows. First, when the carrier 2 storing the wafer W is placed on the mounting table 20 from the outside, the lid of the carrier 2 is removed together with the opening / closing portion 21 and the delivery means A1. Thus, the wafer W is taken out. Then, the wafer W is transferred to the main transfer means A2 via a transfer unit (not shown) that forms one stage of the shelf unit U1, and is pre-processed as a coating process on one shelf in the shelf units U1 to U3. For example, a hydrophobic treatment and a cooling treatment are performed, and then, as will be described in detail later, a water repellent film is formed after a resist is applied by the application unit 30. Further, a unit for forming an antireflection film may be provided, and the antireflection film may be applied to the wafer W instead of the hydrophobic treatment. Next, the wafer W is heated (baked) by a heating unit forming one shelf of the shelf units U1 to U3, and further cooled, and then transferred to the interface unit B3 via the delivery unit of the shelf unit U3. In this interface part B3, the wafer W is transferred to the exposure part B4 through a path of, for example, delivery means A4 → shelf unit U6 → delivery means A5, and immersion exposure is performed. The exposed wafer W is transferred to the main transfer means A2 through the reverse path, and a developing solution is supplied to the surface of the wafer W by the developing unit 27 to develop the resist, thereby forming a resist mask having a predetermined pattern shape. Is done. Thereafter, the wafer W is returned to the original carrier 2 on the mounting table 20.

  Subsequently, a coating apparatus incorporated in the coating unit 30 will be described with reference to FIGS. 3 and 4. In the figure, reference numeral 3 denotes a spin chuck for sucking and sucking the central portion on the back surface side of the wafer W and holding it horizontally. The spin chuck 3 is connected to a drive mechanism 32 via a shaft portion 31, and the spin chuck 3 is configured to be able to rotate and lift while the wafer W is held by the drive mechanism 32.

  A cup body 4 is provided outside the periphery of the wafer W held by the spin chuck 3 so as to surround the wafer W and open on the upper side. The upper end side of the side peripheral surface of the cup body 4 is inclined inward, and the tip is bent downward. On the bottom side of the cup, a liquid receiving portion 41 having a concave shape is formed on the lower peripheral side of the wafer W over the entire circumference. The liquid receiving portion 41 is divided into an outer region and an inner region over the entire circumference by a vertical partition wall 42, and a drain for a stored coating solution or the like is discharged at the bottom of the outer region. A drainage port 43 is provided, and an exhaust port 44 is provided in the inner region. A circular plate 45 is provided on the lower side of the wafer W, and a ring member 46 is provided so as to surround the outer side of the circular plate 45. Further, an end plate 47 extending downward is provided on the outer end surface of the ring member 46 so as to enter the outer region, and the coating liquid is transmitted through the surface of the end plate 47 and the ring member 46 in the outer region. It is comprised so that it may be guided to. Although not shown, lifting pins that support the back side of the wafer W and can be lifted are provided vertically through the circular plate 45, and the lifting pins and, for example, the main transfer means A2 cooperate with each other. The wafer W is configured to be transferred to the spin chuck 3.

  A resist supply nozzle 5 having a discharge port 5a of a fine hole is provided so as to be able to move up and down, so as to face, for example, the center of the surface of the wafer W held by the spin chuck 3. The resist supply nozzle 5 is connected to a resist supply source 52 via a supply path 51. Further, a liquid supply means (not shown) such as a bellows pump capable of adjusting a discharge flow rate by changing a discharge stroke is provided in the middle of the supply path 51. Etc. are provided. As shown in FIG. 4, the resist supply nozzle 5 is detachably supported on one end side of a nozzle arm 53 that is a support member, and the other end side of the nozzle arm 53 is provided with a lifting mechanism (not shown). It is connected to the base 54. Further, the movable base 54 is configured to be movable in the lateral direction along a guide member 55 extending in the longitudinal direction on the bottom surface of the exterior body of the unit, for example.

  In the drawing, reference numeral 56 denotes a standby portion of the resist supply nozzle 5. In the nozzle standby portion 56, a plurality of resist supply nozzles 5 are arranged for different types of resists. Although not shown, each resist supply nozzle 5 is connected with a supply path 51, a resist supply source 52, and a liquid feeding means, and a resist supply nozzle 5 capable of discharging a predetermined resist by a nozzle arm 53 is a nozzle standby unit. 56, and is arranged at a predetermined discharge position to perform a resist supply operation.

  Further, the coating unit 30 includes a first liquid supply nozzle 6 which is an upper nozzle for supplying either the water-repellent film coating liquid or the cleaning liquid to the front surface side and the back surface side of the wafer W on the spin chuck 3. A second liquid supply nozzle 60 which is a lower nozzle is provided. The first liquid supply nozzle 6 is disposed so as to be inclined so that the discharge liquid discharged from the discharge port 6a of the fine pore at the tip thereof reaches the peripheral edge of the wafer W from the upper side on the inside. Further, the first liquid supply nozzle 6 is connected via a nozzle arm 61 to a moving base 62 having a lifting mechanism (not shown). The moving base 62 does not interfere with the resist supply nozzle 5 along the guide member 55. And can be moved in the horizontal direction.

  The second liquid supply nozzle 60 is provided on the circular plate 45, and the discharge port 60 a is inclined so that the coating liquid reaches the peripheral edge of the wafer W from below inside. One end side of a supply path 63 is connected to the first liquid supply nozzle 6 and the second liquid supply nozzle 60, respectively, and the other end side of the supply path 63 is branched to dissolve the coating liquid supply source 64 and the resist. For example, a solvent supply source 65 such as thinner and a nitrogen supply source 66 for purging the supply path 63 are connected. Reference numeral 67 denotes a switching unit, for example, a switching valve for switching the supply of coating liquid, thinner and nitrogen, and V1 and V2 are valves for enabling liquid supply independently from the upper nozzle 6 and the lower nozzle 60. . That is, in this example, the first liquid supply nozzle 6 and the second liquid supply nozzle 60 constitute the water repellent film forming means. In the middle of each supply path 63, liquid feeding means, for example, a bellows pump capable of adjusting the discharge flow rate by changing the discharge stroke is provided. The coating liquid is a water-repellent film formed on a predetermined portion of the wafer W, for example, a contact angle of 90 to 100 ° with respect to a liquid that forms a liquid layer formed on the surface of the wafer W during immersion exposure, such as water. A solution having a surface state as described above is selected. The coating unit 30 may be configured as a water-repellent film unit (TC) without the resist coating means.

  Next, the configuration of the developing device incorporated in the developing unit 27 will be briefly described with reference to FIG. In the figure, reference numeral 7 denotes a spin chuck for holding the wafer W in a horizontal position, and a cup body 70 having an opening on the upper side is provided so as to surround the side of the wafer W on the spin chuck 7. The cup body 70 includes an outer cup 71 and an inner cup 72 that can be raised and lowered, and a liquid receiving portion 73 that forms a recess. Further, for example, a horizontally long developer nozzle 74 having a linear developer discharge port that is the same as or longer than the diameter of the wafer W is provided to face the surface of the wafer W. It is provided so that it can be moved horizontally and moved up and down by a drive mechanism (not shown).

  Further, on the upper side and the lower side of the wafer W, a first solution nozzle 76 and a second solution which are water repellent film removing means for supplying the wafer W with a solution that does not dissolve the resist but dissolves the water repellent film. Liquid nozzles 77 are provided, and the first dissolution liquid nozzle 76 is configured to be movable up and down and back and forth by a drive mechanism (not shown).

  Next, a process of applying a resist to the surface of the wafer W, which is a substrate, using the above-described coating apparatus will be described with reference to FIG. First, in a state where the nozzles 5 and 6 are arranged at the standby position outside the cup body 4, the wafer W is loaded into the coating apparatus by the main transfer means A2 and guided above the spin chuck 3, and then the main chuck A3. The wafer W is delivered to the spin chuck 3 by the cooperative action of the transfer means A2 and the lifting pins (not shown), and the back side thereof is sucked and sucked and held in a horizontal posture.

  Subsequently, for example, a resist supply nozzle 5 corresponding to the type of resist planned based on a process recipe selected by an operator or preselected is taken out from the nozzle standby unit 56 by the nozzle arm 53 and discharged. The hole 5 a is set at a discharge position slightly lifted from the center of the surface of the wafer W. As shown in FIG. 6A, the wafer W is rotated about the vertical axis by the spin chuck 3 and the resist is supplied to the center of the surface of the wafer W at a predetermined supply flow rate. This resist spreads outward along the surface of the wafer W due to the action of centrifugal force, and as a result, the resist is applied to the entire surface of the wafer W in the form of a thin film.

  Thereafter, as shown in FIG. 6B, the supply of the resist from the nozzle 5 is stopped, and the solvent component is evaporated from the resist on the wafer W by increasing the rotation speed of the wafer W and performing spin drying. Then, a resist film is formed on the surface of the wafer W by the remaining resist component. Subsequently, after the liquid supply nozzle 6 is guided to a predetermined position, the wafer W is rotated and the valve V1 is opened. As shown in FIG. 6C, from the liquid supply nozzle 6 to the peripheral portion on the surface side of the wafer W. The thinner from the solvent supply source 65 is supplied to remove the resist at the peripheral edge of the wafer W, for example, the portion extending from the outer edge to the inner side of 2 to 3 mm.

  Subsequently, after switching the switching valve 67 to the nitrogen supply source 66 side and purging the nozzle 6 and the supply path 63 with nitrogen, switching is performed while rotating the wafer W at a low speed around the vertical axis as shown in FIG. The valve 67 is switched to the coating liquid supply source 64, and the valve V2 is opened to supply the water repellent film coating liquid from the first and second liquid supply nozzles 6 and 60 to the peripheral portion from which the resist has been removed. The timing of supplying from the upper and lower nozzles 6 and 60 may not be the same. For example, each may be supplied independently at an optimal timing. Since the coating solution has low viscosity and the dry state is less affected by temperature, the film thickness after film formation depends particularly on the rotation speed, so the rotation speed of the wafer W is set to a rotation speed of 100 rpm, for example. Is preferred. For example, as schematically shown in FIG. 7, the coating liquid 200 supplied to the wafer W spreads outward along the surface of the wafer W, and further wraps around the side end face due to surface tension, so that the coating liquid from above and below is applied. Connect with each other. Thereafter, after purging with nitrogen, the valves V1 and V2 are closed, while the wafer W is rotated at a high speed and spin-dried. As a result, as shown in FIG. 6E, the water-repellent film 201 straddling the peripheral edge of the wafer W from the peripheral edge on the surface side to the peripheral edge on the back surface is formed by the solid component remaining after evaporation of the solvent in the coating solution. It will be formed outside the resist film 202. Thereafter, the wafer W is unloaded by the main transfer means A2 and loaded into the heating unit for baking.

  The wafer W that has been subjected to the baking process is subsequently carried into the exposure unit B4 via the interface unit B3, and is placed on a predetermined placement region in the sputtering of the exposure unit B4. In detail, as described in the “Background Art” section, the exposure means 1 is arranged so as to face the surface of the wafer W, and immersion exposure is performed. The wafer W that has been subjected to the immersion exposure is carried into a heating unit in the shelf unit U6 via the interface unit B3, and is subjected to a process called PEB (post exposure bake) that heats the resist at a predetermined temperature. The acid generated from the acid generating component contained in the exposed resist is diffused into the resist. The resist component chemically reacts by the catalytic action of the acid, so that, for example, a positive type resist becomes soluble in a developing solution, and when a negative type resist is used, it becomes insoluble.

  Thereafter, the wafer W is carried into the developing unit 27 by the main transfer means A2, and first the wafer W is rotated and the solution is supplied to the water-repellent film forming region which is the peripheral portion of the wafer W by the solution nozzles 76 and 77. Then, the water repellent film is dissolved and removed. Further, the dissolved solution turns around the side end surface by the action of the centrifugal force of the rotating wafer W and the surface tension of the dissolved solution, and the water-repellent film on the side end surface is dissolved and removed. The rotation of the wafer W is stopped, and then the first developer nozzle 74 is scanned from one end side to the other end side of the wafer W while discharging the developer. As a result, the developer is uniformly supplied to the surface of the wafer W, and a resist mask having a predetermined pattern is formed on the surface of the wafer W by dissolving a portion that is soluble in the developer.

  According to the above-described embodiment, by forming a water-repellent water-repellent film across the back-side peripheral edge from the front-side peripheral edge of the wafer W coated with a resist on the front surface, Thereafter, when immersion exposure is performed on the resist, it is possible to prevent the liquid forming the liquid layer from being repelled on the water-repellent film and spilling from the outer peripheral edge of the wafer W. For this reason, it is possible to prevent water in the exposure apparatus. Further, as shown in FIG. 8, for example, a liquid layer that transmits light is repelled on the peripheral portion of the wafer W and the surface of the liquid receiving ring 13 that is a water-repellent member surrounding the outer peripheral edge of the wafer W. It is possible to prevent water from spilling from the gap between W and the liquid receiving ring 13. In particular, since the water-repellent film is formed up to the side edge surface and the back surface side peripheral portion of the wafer W, water is hardly pulled by the wafer W due to the surface tension, so that the water does not flow down from the gap. Can be prevented. As a result, the temperature and humidity in the exposure apparatus can be kept constant, and the electrical system can be prevented from being short-circuited. Furthermore, since the semiconductor device made of an integrated circuit can be formed by exposing to the vicinity of the outer peripheral edge of the wafer W, the utilization factor of the wafer W can be increased.

  In the embodiment described above, the invention is not limited to the configuration in which the water-repellent film is formed to extend from the front surface side peripheral portion to the back surface side peripheral portion through the side end surface in a state where the peripheral portion resist is removed. The water-repellent film may be formed in a state where In this case, the thickness of the water-repellent film is, for example, 500 mm, which is extremely small with respect to the resist film thickness, so that the step height is reduced by aligning the surface height between the peripheral edge of the wafer W and the inside thereof. This is advantageous in that the behavior of the liquid layer is improved when the wafer W and the exposure means 1 are relatively moved laterally. Further, in this case, for example, before being carried into the exposure section B4, the wafer is carried into the peripheral exposure unit 29 and irradiated with light from above the water-repellent film to expose the resist at the peripheral part through the water-repellent film. Thereafter, immersion exposure is performed and the developer is removed when the developer is supplied by the developing unit 27. It should be noted that the same effect can be obtained even when the resist at the peripheral edge is removed by making the thickness of the water-repellent film equal to the film thickness of the resist.

  Next, another embodiment of the present invention will be described with reference to FIGS. In the figure, reference numeral 8 denotes, for example, a rectangular U-shaped member which is a coating liquid supply unit for supplying a coating liquid to the peripheral portion of the wafer W to form a water-repellent film. The recessed area is formed as a processing space 81 for processing the wafer W. The U-shaped member 81 is configured so as to be able to advance and retreat in the diameter direction of the wafer W by a driving mechanism including an arm 80, and the U-shaped member 8 moves horizontally to move the peripheral portion of the wafer W into the processing space 81. A part of the liquid enters, and the coating liquid can be supplied to the peripheral edge. The arm 80 is arranged so that it can move without interfering with the nozzle arms 53 and 63. Discharge holes 82 and 82 for supplying the coating liquid are respectively provided on the upper surface side and the lower surface side of the processing space 81, and a cleaning liquid supply source 84 is connected to the discharge holes 82 and 82 through a supply path 83. Has been. Further, for example, a side surface of the processing space 81 is provided with a suction hole 85 for sucking and collecting the coating liquid supplied from the supply hole 82, and the suction hole 85 is provided with a suction means 87 via a suction path 86. Is connected. In addition, about the place which employ | adopts the same structure as the apparatus of other FIG. 3, the description is abbreviate | omitted by attaching | subjecting the same code | symbol, and description of the developing solution nozzles 5 and 6 is abbreviate | omitted for convenience of drawing.

  In the configuration as described above, after the resist is applied to the surface of the wafer W, and the resist at the peripheral edge is removed by the thinner supplied from the liquid supply nozzle 6 (see FIGS. 6A to 6C). Then, the spin chuck 3 is raised, and then the U-shaped member 8 approaches the wafer W by the arm 80, and a part of the peripheral edge of the wafer W enters the processing space 81. Then, the wafer W is rotated about the vertical axis, and the coating liquid is discharged from the supply holes 82 and 82 toward the peripheral edge of the wafer W. Thereby, a water-repellent film is formed from the front surface side peripheral portion of the wafer W through the side end surface to the back surface side peripheral portion (see FIG. 7). Thereafter, the supply operation of the coating solution is stopped, and then the U-shaped member 8 moves backward to lower the spin chuck 3, and then the wafer W is rotated at a high speed to dry the coating solution by spin drying. Get. Then, exposure and development processes are performed in the same manner as described above to form a resist pattern. Even with such a configuration, since the water-repellent film can be formed on the peripheral edge of the wafer W, the same effect as described above can be obtained. Note that, as described above, the switching valve 67 may be provided to supply thinner that dissolves the resist through the discharge hole 82 of the U-shaped member 8.

  Next, still another embodiment of the present invention will be described with reference to FIG. The coating apparatus of this example is, for example, the water repellent film unit (TC) of FIG. 2 and includes the liquid supply nozzles 6 and 60 described above, but the liquid supply nozzle 6 above the wafer W is the central portion of the wafer W. Dispose the discharge hole with the lower side facing. The other parts that adopt the same configuration as that of the apparatus shown in FIG. In such a configuration, the wafer W is rotated, the coating liquid is supplied from the liquid supply nozzle 60 to the peripheral edge of the back surface of the wafer W, and the coating liquid is supplied from the liquid supply nozzle 6 to the center of the wafer W. . In this case, the coating solution on the surface of the wafer W spreads by centrifugal force from the center toward the outside, and when reaching the peripheral edge, it wraps around the side end surface due to surface tension and is connected to the back side coating solution at the side end surface. As a result, a water repellent film can be formed from the front surface of the wafer W to the rear surface side peripheral edge via the side end surface. In this example as well, a configuration provided with the resist supply nozzle 5 may be adopted.

  Even in this case, since the water-repellent film can be formed on the peripheral portion of the wafer W, the same effect as described above can be obtained. Furthermore, in this example, since a water-repellent film can be formed on the entire resist surface, for example, when a hydrophilic resist is used, a liquid forming a liquid layer infiltrate the resist during immersion exposure. There is no or very little. For this reason, it can suppress that the component eluted from the resist adheres to the lens of the exposure means 1, for example, and as a result, a highly accurate resist pattern can be obtained.

  Furthermore, in the above-described embodiment, the water-repellent film is less likely to pull liquid such as water that forms a liquid layer by surface tension when the exposure means 1 is laterally moved by its water-repellent action. For this reason, when the pattern is transferred sequentially by moving the wafer W and the exposure means 1 relatively laterally, the behavior of the liquid layer is good. For example, the occurrence of fluctuations in the liquid layer can be suppressed, so that highly accurate exposure can be performed. Can be realized. In addition, after the exposure unit 1 reaches the transfer area, the time for standing until the fluctuation in the liquid film is eliminated can be shortened. In this example, since the water-repellent film is formed on the entire surface of the wafer W, the step of removing the peripheral resist may be omitted, or the water-repellent film may be removed after removing the peripheral resist. You may make it form. Furthermore, in this case, as described above, the peripheral edge portion and the inner surface height may be aligned.

  In the present invention, the water repellent film does not necessarily have to be formed in the coating unit (COT) 30 while selecting the optimum process according to the type of resist. For example, after the resist is applied to the wafer W by the water repellent film unit (TC) having the water repellent film forming means such as the first and second liquid supply nozzles 6 and 60 and the U-shaped member 8 described above. Alternatively, after being pre-baked by the heating unit and cooled to a predetermined temperature by the cooling unit, it is carried into the water-repellent film unit and a water-repellent film may be formed on the entire resist surface, for example. Also, a thinner is supplied to the wafer W coated with resist in the coating unit (COT) 30 to remove the peripheral resist, and then unloaded, pre-baked by the heating unit, and then loaded into the water-repellent film unit. The coating liquid is applied to the peripheral portion by the one liquid supply nozzle 6 and the second liquid supply nozzle 60. Or you may make it apply | coat a coating liquid from the upper and lower discharge holes 82 and 82 of the U-shaped member 8. FIG. Furthermore, when the liquid type of the water-repellent coating liquid is different, these may be selected.

  Further, in the present invention, the substrate to be processed is not limited to the wafer W, and can be applied to, for example, coating / development processing of an LCD substrate or a photomask reticle substrate.

It is a top view which shows embodiment of the coating / developing apparatus of this invention. 1 is a perspective view showing an embodiment of a coating / developing apparatus according to the present invention. It is a longitudinal cross-sectional view which shows the coating unit incorporated in the said coating / developing apparatus. It is a top view which shows the coating unit integrated in the said coating / developing apparatus. It is a longitudinal cross-sectional view which shows the image development unit integrated in the said coating / developing apparatus. It is process drawing which shows the process of apply | coating a resist on the surface of a wafer using the said coating device. It is explanatory drawing which shows the water-repellent film formed in the peripheral part of a wafer. It is explanatory drawing which shows a mode that the peripheral part of a wafer is immersion-exposed. It is explanatory drawing which shows the other example of the coating unit integrated in the said coating / developing apparatus. It is explanatory drawing which shows the other example of the liquid supply part of the said application | coating unit. It is explanatory drawing which shows the other example of the water repellent film | membrane unit integrated in the said application | coating / development apparatus. It is explanatory drawing which shows the method of performing immersion exposure with respect to the resist of a wafer surface. It is explanatory drawing which shows the method of performing immersion exposure with respect to the resist of a wafer surface. It is explanatory drawing which shows a mode that the peripheral part of a wafer is immersion-exposed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 Spin chuck 4 Cup body 5 Resist supply nozzle 6 1st liquid supply nozzle 60 2nd liquid supply nozzle 8 Liquid supply part

Claims (12)

In a coating and developing apparatus comprising a resist coating unit for coating a resist on the surface of a substrate and a developing unit for developing a substrate after exposure,
A substrate holding part for horizontally holding the substrate;
A rotation drive unit that rotates the substrate holding unit around a vertical axis;
A coating liquid for forming a water-repellent film is supplied to the substrate while rotating the substrate after resist coating while being held by the substrate holding unit, and the back surface from at least the peripheral portion on the surface side of the substrate through the side end surface A coating liquid supply unit that forms a water-repellent film across the peripheral edge of the side,
The coating / developing apparatus, wherein the developing unit develops the substrate after exposure in a state where a liquid layer that transmits light is formed on the surface of the substrate on which the water repellent film is formed.   The coating / supplying unit according to claim 1, wherein the coating liquid supply unit is provided in a resist coating unit, and the substrate holding unit also serves as a substrate holding unit used when coating the resist on the substrate. Development device.   The coating liquid supply unit includes an upper nozzle that supplies the coating liquid to the peripheral portion on the front surface side of the substrate held by the substrate holding unit, and a lower nozzle that supplies the coating liquid to the peripheral portion on the back surface side of the substrate. The coating / developing apparatus according to claim 1, wherein the coating / developing apparatus is provided.   The coating liquid supply unit includes a U-shaped member horizontally movable between a position where the peripheral edge of the substrate is inserted into the space and a position where the peripheral edge of the substrate is separated from the space, and the U-shaped member in the U-shaped member An upper nozzle that opens into the space and sucks and exhausts air to the opposite side to the center side of the substrate, and supplies the coating liquid to the peripheral portion on the front surface side of the substrate, and the peripheral portion on the back surface side of the substrate 4. The coating / developing apparatus according to claim 3, wherein a lower nozzle for supplying a coating solution to the U-shaped member is provided on the U-shaped member.   4. The coating / developing apparatus according to claim 3, further comprising means for removing a resist at a peripheral edge where the water repellent film is formed on the substrate surface.   The substrate is provided with a peripheral exposure portion that exposes the peripheral portion of the substrate, and the resist-coated substrate is exposed at the peripheral exposure portion, and then the resist on the peripheral portion is removed by a developer. The coating and developing apparatus according to claim 5.   The coating liquid supply unit includes an upper nozzle that supplies the coating liquid to the central portion on the front surface side of the substrate held by the substrate holding unit, and a lower nozzle that supplies the coating liquid to the peripheral portion on the back surface side of the substrate. The coating / developing apparatus according to claim 1, wherein a water-repellent film is formed on the entire surface of the substrate. Applying a resist to the surface of the substrate;
Next, while the substrate is held horizontally on the substrate holding part, the coating liquid is supplied to the substrate while rotating the substrate holding part, and from at least the peripheral part on the front side of the substrate to the peripheral part on the back side through the side end face. Forming a straddling water-repellent film;
Thereafter, a step of exposing the surface of the substrate with a liquid layer formed on the surface of the substrate;
And a step of developing the exposed substrate, and a method of forming a resist pattern.   The step of applying the resist to the substrate is performed in a state where the substrate is held horizontally on the substrate holding portion, and the step of forming the water repellent film is performed while holding the substrate on the substrate holding portion. The method for forming a resist pattern according to claim 8.   10. The step of forming the water-repellent film is a step of supplying a coating liquid to a peripheral portion on the front surface side of the substrate and supplying a coating liquid to a peripheral portion on the back surface side. A method for forming a resist pattern.   11. The step of removing a resist at a peripheral portion where the water repellent film is formed on the substrate surface is performed after the step of applying the resist and before the step of forming the water repellent film. A method for forming a resist pattern. The method for forming a resist pattern according to claim 8 or 9, wherein the step of supplying the coating solution from the surface side of the substrate is a step of supplying the coating solution to the central portion of the substrate and supplying the coating solution to the entire surface of the substrate. .

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