JP4111342B2 - Peripheral exposure method and apparatus - Google Patents

Description

  The present invention relates to a peripheral exposure method and apparatus for an object to be processed such as a semiconductor wafer coated with a resist and a glass substrate for LCD.

  In general, in a manufacturing process of a semiconductor wafer or the like, a photolithography technique is used to form a resist pattern on the surface of an object to be processed such as a semiconductor wafer or an LCD substrate. This photolithography technology includes a resist coating process for applying a resist solution to the surface of an object to be processed, an exposure processing process for exposing a circuit pattern to the formed resist film, and a development for supplying a developer to the substrate after the exposure process. And processing steps. In this case, in the resist coating process, a resist solution is supplied (dropped and discharged) to the surface of the rotating object to be processed, and a resist film is formed on the surface of the object to be processed by centrifugal force. For this reason, the film thickness of the resist film at the periphery of the object to be processed is increased, and the film thickness uniformity on the surface of the object to be processed is impaired. In addition, there is a risk that the surplus resist film in the peripheral portion may be peeled off during transport or processing of the object to be processed to generate particles. In order to solve these problems, conventionally, the peripheral portion of the object to be processed after resist coating is exposed, and the excess resist film on the peripheral part of the surface of the object to be processed is removed by development processing. (For example, refer to Patent Document 1).

According to this peripheral exposure technique, a uniform exposure dose of UV light is irradiated by irradiating light (for example, UV light) with a circular or rectangular irradiation pattern onto an unnecessary resist film in the peripheral portion of the object to be processed. It is possible to prevent resist residue and the like due to poor exposure.
JP-A-8-148420 (Claims, FIGS. 2, 3, 4, and 6)

  However, the conventional peripheral exposure technique has a problem that the shape (tilt angle) of the resist removal portion cannot be improved because the optical contrast of the irradiation light on the object to be processed cannot be controlled. Further, in the conventional peripheral exposure technology, in order to remove the resist on the end face of the object to be processed, the peripheral part of the object to be processed is exposed by a dedicated exposure device before developing the resist, and then development processing is performed. In addition, a long time is required for the processing, and the apparatus may be increased in size.

  The present invention has been made in view of the above circumstances, and it is possible to improve the shape (tilt angle) of the resist removal portion by increasing the optical contrast of the irradiation light on the object to be processed and to shorten the processing time. An object of the present invention is to provide a peripheral exposure method and apparatus capable of reducing the size of the apparatus.

In order to solve the above-described problems, the peripheral exposure method of the present invention is configured to move the object to be processed on which a resist is applied and the light irradiation unit relatively along the peripheral part of the object to be processed. In the peripheral exposure method for exposing the peripheral portion of the processing body over a predetermined width, the light irradiation means includes a laser light source and a two-beam interference generator for generating interference fringes by superimposing two light beams from the laser light source. A processing liquid is supplied from the processing liquid supply means to the surface of the object to be processed, a liquid film is formed on the surface of the object to be processed, and the light exit port of the two-beam interference generator is connected to the object to be processed. The optical contrast formed on the surface of the object to be processed is increased by exposing the substrate to the liquid film at the periphery of the substrate to change the refractive index of the emitted light, thereby exposing the surface of the object to be processed (claim 1). .

In this invention, while rotating the said to-be-processed object on a horizontal surface, moving the said process liquid supply means to the radial direction of the said to-be-processed object in the area | region which does not interfere with a two- beam interference production | generation object , supplying a process liquid It is preferable to form a liquid film (claim 2).

  Further, as the processing liquid for forming the liquid film, any liquid can be used. For example, a developing liquid or pure water can be used as the processing liquid (claims 3 and 4).

The two-beam interference generator is exposed while moving in the radial direction of the object to be processed in the peripheral region of the object to be processed (Claim 5 ), or the two-beam interference generator is processed with the object to be processed. preferably better to exposure in a state of being inclined to the tangent (claim 6).

Further, the peripheral exposure apparatus of the present invention embodies the peripheral exposure method, and includes a holding unit that holds an object to be processed coated with a resist, a driving unit that rotates the holding unit on a horizontal plane, a treatment liquid supply means for forming a liquid film by supplying a processing liquid to the surface of the object, comprising a light irradiating means for irradiating the emitted light to the peripheral portion of the object to be processed, the above light irradiating means A two-beam interference generator for generating interference fringes by superimposing two light beams from the laser light source, and the light output port of the two-beam interference generator is a peripheral part of the object to be processed The liquid film is immersed in the liquid film and the refractive index of the emitted light is changed to increase the optical contrast formed on the object to be exposed (claim 7 ).

In the present invention, the process liquid supply means, is better movably formed in the radial direction of the workpiece in the area that does not interfere with the two-beam interference producers preferred (claim 8).

The processing liquid supply means may be a developer supply nozzle that moves in the radial direction of the object to be processed, or a pure water supply nozzle (claims 9 and 10 ).

Further, the two-beam interference generating body is formed so as to be movable in the radial direction of the object to be processed in the peripheral region of the object to be processed (Claim 11 ), or inclined with respect to the tangent of the object to be processed It is preferable to dispose (claim 12 ).

(1) According to the invention of claim 1 and 7, wherein the processing solution supplying means supplies the treatment liquid to the surface of the workpiece to form a liquid film to the surface of the object, the two-beam interference producers The refractive index of the emitted light can be changed in the liquid film by immersing the light exit port in the liquid film at the periphery of the object to be processed and irradiating (emitting) it from the two-beam interference product. The exposure can be performed with an increased optical contrast formed on the body surface. Therefore, the shape (tilt angle) of the removed portion of the unnecessary resist film in the peripheral portion of the object to be processed can be improved.

(2) According to the second and eighth aspects of the invention, the object to be processed is rotated on a horizontal plane, and the processing liquid supply means is moved in the radial direction of the object to be processed in a region where it does not interfere with the two- beam interference generator. In the state where the liquid film is formed while supplying the processing liquid, the light exit port of the two-beam interference generator is immersed in the liquid film for exposure processing, so that the processing time can be further shortened in addition to the above (1). In addition, the size of the apparatus can be reduced.

(3) According to the third and ninth aspects of the invention, the exposure process and the development process are performed by immersing the light exit of the two-beam interference product in the liquid film formed by the developer and performing the exposure process. It can be performed simultaneously or sequentially. Therefore, in addition to the above (1) and (2), the processing time can be further shortened and the apparatus can be miniaturized.

(4) According to the inventions described in claims 4 and 10 , a cleaning process with pure water is performed by immersing the light exit of the two-beam interference product in a liquid film formed with pure water and performing an exposure process. The exposure process can be performed at the same time. Therefore, in addition to the above (1) and (2), the processing time can be further shortened and the apparatus can be miniaturized.

(5) According to the first and seventh aspects of the present invention, interference fringes can be generated by superimposing two light beams from the laser light source, and the interference fringes are refracted in the liquid forming the liquid film. Then, the resist film surface is exposed to light, so that the exposure can be performed with an increased optical contrast. In this case, exposure is performed while the peripheral exposure width of the object to be processed is ensured by exposing the two- beam interference generating body in the peripheral region of the object to be processed while moving in the radial direction of the object to be processed. (Claims 5 and 11 ). Further, the two-beam interference producers, by exposing in a state of being inclined to the tangent of the object can be exposed processing to ensure peripheral exposure width of the object (claim 6, 12 ).

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the best embodiment of the present invention will be described in detail with reference to the accompanying drawings. Here, a case where the peripheral exposure method (apparatus) according to the present invention is applied to a semiconductor wafer resist coating / development processing system will be described.

  As shown in FIGS. 1 and 2, the resist coating / development processing system includes a loading / unloading unit 1 for loading / unloading a cassette C in which a wafer W as a processing object is stored, and this loading / unloading unit 1. The processing unit 2 that performs resist coating / development processing on the wafer W taken out from the cassette C and the exposure unit 4 that is connected to the processing unit 2 via the interface unit 3 are mainly configured.

  The carry-in / carry-out unit 1 is disposed between the cassette station 6 and the cassette station 6 provided with a placement unit 5 on which a plurality of cassettes C for hermetically storing a plurality of, for example, 25 wafers W can be placed. An opening / closing part 7 provided on the wall surface and delivery means A1 for taking out the wafer W from the cassette C via the opening / closing part 7 are provided.

  In the processing section 2, the wafer W is transferred between the processing units including shelf units U1, U2, U3 in which heating / cooling units are arranged in order from the front side and coating / developing units described later. Conveying means A2 and A3 are provided alternately. That is, the shelf units U1, U2, U3 and the main transfer means A2, A3 are arranged in a line in the front-rear direction when viewed from the loading / unloading unit 1 side, and an opening for wafer transfer (not shown) is formed at each connection site. Thus, the wafer W can freely move in the processing unit 2 from the shelf unit U1 on one end side to the shelf unit U3 on the other end side. 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 when viewed from the carry-in / out portion 1, and one surface on the right side liquid processing unit U4 and U5 side which will be described later. It is placed in a space surrounded by a partition wall 8 composed of a part and a back part forming one surface on the left side. In the figure, reference numerals 12 and 13 denote temperature / humidity adjusting units including a temperature adjusting device for processing liquid used in each unit, a duct for adjusting temperature / humidity, and the like.

  For example, as shown in FIG. 1, the liquid processing units U4 and U5 are provided with a coating unit COT and a peripheral exposure according to the present invention on a storage portion 14 that forms a space for supplying a chemical solution such as a coating solution (resist solution) and a developing solution. The developing unit DEV including the apparatus and the developing device, the antireflection film forming unit BARC, and the like are stacked in a plurality of stages, for example, five stages. The 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. And a heating unit for heating (baking) the wafer W, a cooling unit for cooling the wafer W, and the like.

  The exposure unit 4 is connected to the back side of the shelf unit U3 in the processing unit 2 via an interface unit 3 including, for example, a first transfer chamber 15 and a second transfer chamber 16. Inside the interface unit 3, a shelf unit U6 and a buffer cassette C0 are provided in addition to two delivery means A4 and A5 for delivering the wafer W between the processing unit 2 and the exposure unit 4.

  An example of the wafer flow in the resist coating / development processing system configured as described above is as follows. First, when the cassette C in which the wafer W is stored is loaded from the outside onto the loading table of the loading / unloading unit 1. Then, the lid of the cassette C is removed together with the opening / closing part 7, and the wafer W is taken out by the delivery means A1. Then, the wafer W is delivered to the main transfer means A2 via a delivery unit (not shown) that forms one stage of the shelf unit U1, and is pre-processed for coating processing on one shelf in the shelf units U1 to U3. For example, after an antireflection film forming process and a cooling process are performed, a resist solution is applied by the application unit COT. 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 3 via the delivery unit of the shelf unit U3. In the interface unit 3, the wafer W is transferred to the exposure unit 4 through a path of delivery means A4 → shelf unit U6 → delivery means A5, for example, and exposure is performed. After the exposure, the wafer W is transferred to the main transfer means A2 through the reverse path, and developed by the developing unit DEV. At this time, the peripheral portion of the wafer W is exposed by the peripheral exposure apparatus according to the present invention, and the unnecessary resist is removed by the developer. Thereafter, the wafer W is returned to the original cassette C on the mounting table of the loading / unloading unit 1.

  Next, a peripheral exposure apparatus according to the present invention will be described with reference to FIGS.

<First Embodiment>
FIG. 3 is a schematic sectional view showing the first embodiment of the peripheral exposure apparatus according to the present invention, and FIG. 4 is a plan view of FIG.

  As described above, the peripheral exposure apparatus is incorporated in the developing unit DEV, and rotates the spin chuck 20 on a horizontal plane as a holding means for holding the wafer W coated with the resist R and the spin chuck 20 on a horizontal plane. Irradiating light is emitted to the driving means 21 that moves up and down, the developing solution supply nozzle 24 that is a processing solution supply unit that supplies a developing solution as a processing solution to the surface of the wafer W and forms the liquid film 22, and the periphery of the wafer W. The light irradiating means 30 is mainly configured.

  In this case, a cup 40 whose upper side is opened so as to surround the wafer W on the spin chuck 20 is provided. The cup 40 is composed of an outer cup 41 having a square shape on the upper side and a cylindrical shape on the lower side, and a cylindrical inner cup 42 whose upper side is inclined inward, and the outer cup 41 is connected by an elevating mechanism 43 connected to the outer cup 41. 41 is moved up and down, and the inner cup 42 is configured to be lifted and lowered by being pushed up by a step formed on the inner peripheral surface of the lower end side of the outer cup 41.

  A circular plate 44 is provided on the lower side of the spin chuck 20, and a liquid receiving portion 45 having a concave cross section is provided on the outer periphery of the circular plate 44 over the entire circumference. A drain discharge port 46 is formed on the bottom surface of the liquid receiving part 45, and the developer and the rinse liquid that are spilled from the wafer W or shaken off and stored in the liquid receiving part 45 pass through the drain discharge port 46. Discharged outside the device. Further, a ring member 47 having a mountain-shaped cross section is provided outside the circular plate 44. Although not shown, for example, three elevating pins that pass through the circular plate 44 are provided, and the wafer W can be delivered to the spin chuck 20 by the cooperative action of the elevating pins and a substrate transfer means (not shown). It is configured.

  As shown in FIG. 5, the developer supply nozzle 24 is formed in a wedge shape so that the width is narrowed downward, for example, and a slit-like shape for discharging a belt-like developer on the lower end surface thereof. A discharge port (not shown) is provided. The discharge port is formed so that its length direction is directed from the peripheral edge of the wafer W toward the central portion. Here, “slit shape extending from the peripheral edge toward the central portion” means not only when extending along a straight line (radius) from one edge of the wafer W toward the central portion, but also with a slight angle with respect to this line. This includes cases where they are crossed. Further, the “strip shape” does not have to have a strictly rectangular horizontal section, and includes, for example, a trapezoidal shape or a case where each side has a wave shape.

  The developer supply nozzle 24 configured as described above is connected to a developer supply source 26 via a developer supply conduit 25. In the middle of the developing solution supply pipe 25, a heat exchanger 27, which is a temperature adjusting unit for adjusting the temperature of the developing solution, and a liquid feeding means (not shown) such as a bellows pump are provided.

  Further, the developer supply nozzle 24 is supported on one end side of the nozzle arm 24a, the other end side of the nozzle arm 24a is connected to a moving base 24b provided with a lifting mechanism (not shown), and the moving base 24b is, for example, A linear movement mechanism 24c is provided, and is configured to be movable in the lateral direction, that is, in the radial direction of the wafer W in a region that does not interfere with the light irradiation means 30 along the guide member 24d that extends in the Y direction on the bottom surface of the exterior body of the unit. ing.

  A rinsing liquid nozzle 28 that can move horizontally (moving in the radial direction of the wafer W) and has a discharge port (not shown) for supplying (discharging) rinsing liquid, for example, pure water, can be moved up and down at the outer position of the cup 40. Is provided. The rinsing liquid nozzle 28 is connected to an elevating and rotating mechanism 28b through a nozzle arm 28a. The elevating and rotating mechanism 28b does not interfere with the light irradiation means 30 and the developer supply nozzle 24 in the lateral direction (the radius of the wafer W). It is configured to be movable in the direction).

  On the other hand, the light irradiation means 30 includes a laser light source 31 and a two-beam interference generator 33 that generates an interference fringe 32 by superimposing two light beams from the laser light source 31. The two-beam interference generator 33 is configured to be movable in the horizontal and vertical directions. Then, the light exit 35 of the two-beam interference generator 33 is immersed in the liquid film 22 in the peripheral portion of the wafer W, and the refractive index of the emitted light is changed, thereby increasing the optical contrast formed on the wafer W. It is comprised so that it may expose. Here, “immersion” includes any case where the surface of the liquid film 22 or the light emission port 35 is located in the liquid film 22.

  In this case, as shown in FIG. 7, the two-beam interference generator 33 is made of, for example, a quartz material, and has a rectangular base 37 having a light incident port 36 on the upper end surface located on the laser light source 31 side, The rectangular base 37 is formed by a pair of inclined surfaces 38 that are narrowly tapered toward the lower side and formed on opposite sides of the rectangular base 37, and a light emission port 35 that is formed at the lower ends of both inclined surfaces 38. Yes. By the two-beam interference generator 33 formed in this way, the two laser beams from the laser light source 31 are overlapped by both inclined surfaces 38 and emitted from the light exit 35 to generate interference fringes.

  In the present invention, the two-beam interference product 33 is disposed in a state where the light exit 35 is immersed in the developer film 22 formed on the surface of the wafer W as described above. As shown in FIG. 6, the two laser light beams from the laser light source 31 are overlapped by the inclined surfaces 38 and the optical axis emitted from the light emission port 35 is refracted in the liquid film 22 to be the surface of the wafer W (specifically, Interference fringes 32 are generated on the resist film surface. Since the irradiation angle θ of the optical axis at this time becomes an obtuse angle, the interference fringes 32 become fine and exposure can be performed in a state where the optical contrast is enhanced. As a result, the optical contrast of the irradiation light on the wafer W can be increased and the shape (tilt angle) of the resist removal portion can be improved.

  Although the refractive index of the optical axis varies depending on the immersion position of the light exit port 35, as described above, the interference fringe 32 becomes fine and the optical contrast is enhanced as long as the irradiation angle θ of the optical axis is an obtuse angle. Therefore, the immersion position of the light emission port 35 may be arbitrary as long as it is within such a range.

  The driving means 21, the heat exchanger 27 (temperature adjusting unit), the linear moving mechanism 24c, the elevating and rotating mechanism 28b, the moving mechanism 34 and the elevating mechanism 43 are each a central processing unit 50 (hereinafter referred to as a control means). CPU 50) and electrically controlled based on a control signal from CPU 50.

Next, a developing process for removing unnecessary resist in the peripheral portion of the wafer W using the peripheral exposure apparatus will be described. First, in a state where the outer cup 41 and the inner cup 42 are in the lowered position, and the developer supply nozzle 24 and the rinsing liquid nozzle 28 are respectively disposed above the nozzle standby portion, a resist is applied to the surface thereof, and the exposure unit When the wafer W after exposure in 4 is carried in by a substrate transfer means (not shown), the wafer W is delivered to the spin chuck 20 by the cooperative action of the substrate transfer means and lifting pins (not shown). On the other hand, for example, until the wafer W is delivered to the spin chuck 20, the CPU 50 determines the set value of the developer temperature based on the type of resist applied to the wafer W and the information in the memory. In addition, the temperature is adjusted by, for example, the heat exchanger 27 so that the temperature of the developer from the selected developer supply nozzle 24 becomes the temperature set value.

Next, the outer cup 41 and the inner cup 42 are set to the raised position, and the developer discharge start position, for example, the wafer W is slightly outside the outer edge on one end side and slightly higher than the surface of the wafer W. The developer supply nozzle 24 is arranged so that the discharge port is set at a position, and for example, a position slightly higher than the surface of the peripheral portion of the wafer W on the other end side of the wafer W, that is, a developer liquid film 22 is formed. The two-beam interference generator 33 of the light irradiation means 30 is arranged so that the light exit 35 is set at the position where the light is emitted. Further, the rinsing liquid nozzle 28 is disposed at a slightly higher position in the center of the wafer W surface.

  Thereafter, the wafer W is rotated in the horizontal direction at a rotational speed of, for example, 1000 to 1200 rpm, and the developer supply nozzle 24 is moved in the rotation radius direction of the wafer W, that is, outside the wafer W while discharging the developer from the discharge port in a strip shape. Move from the center toward the center. The moving speed of the nozzle at this time is set so that, for example, in the case of an 8-inch wafer W, the ejection port reaches the upper part of the center of the wafer W in 1 to 2 seconds. The set values of the rotation speed of the wafer W and the moving speed of the nozzle are set values of the width of the belt-like developer, that is, the length of the discharge port so that the developer is arranged without any gap in the radial direction of the wafer W, for example. For example, by calculation or by conducting a test in advance.

  Therefore, as shown in FIG. 5, the developer discharged in a band shape from the discharge port is arranged from the outside to the inside of the wafer W so that there is no gap and does not overlap with each other. The developer is supplied spirally throughout. At this time, since the wafer W is rotating, the developer spreads outward along the surface of the wafer W due to the action of centrifugal force, and as a result, a thin liquid film 22 is formed on the surface of the wafer W. Then, the soluble portion of the resist is dissolved in the developer, and the insoluble portion that forms the pattern thereafter remains.

  When laser light is irradiated from the laser light source 31 during the developing process, the two laser light beams pass through the two inclined surfaces 38 of the two-beam interference generator 33 while the laser light passes through the two-beam interference generator 33. Thus, the optical axis emitted from the light exit port 35 is refracted in the liquid film 22 to generate interference fringes 32 on the surface of the wafer W (specifically, the resist film surface). Since the angle θ of the optical axis at this time becomes an obtuse angle, the interference fringes 32 become fine and exposure can be performed in a state where the optical contrast is enhanced. Then, the unnecessary resist is dissolved in the developer, and the unnecessary resist around the wafer W is removed. Thereby, the unnecessary resist can be removed simultaneously with the development processing.

  On the other hand, for example, the rinse liquid nozzle 28 is set in the vicinity of the developer supply nozzle 24 by moving the rinse liquid nozzle 28 in the rotational radius direction of the wafer W in synchronization with the timing of starting the movement of the developer supply nozzle 24. To do. That is, it is stopped slightly before the rinse liquid discharge position above the center of the wafer W.

  The developer supply nozzle 24 discharges for a predetermined time, and then stops the discharge operation and moves backward quickly. Next, a rinsing liquid nozzle 28 is disposed above the central portion of the wafer W so as to be replaced with the developing solution supply nozzle 24, and the rinsing liquid is quickly discharged from the rinsing liquid nozzle 28 for a predetermined time, for example. Supply rinse solution to In this case, a surfactant may be added to the rinse liquid in order to prevent pattern collapse. Since the replacement of the developer supply nozzle 24 and the rinse liquid nozzle 28 can be performed instantaneously or in an extremely short time, in this example, the time during which the developer supply nozzle 24 is moved from the outside of the wafer W toward the center side is the development time. Equivalent to. The rinsing solution may be supplied at least before the developing solution dries. After stopping the discharge of the developing solution, for example, about 1 to 2 seconds to secure a sufficient developing time according to the dissolution rate of the resist, for example. The rinse liquid may be supplied after opening. In this case, the development time is the sum of the movement time of the developer supply nozzle 24 and the time required for the rinse liquid to be supplied after the developer supply nozzle 24 is retracted.

The rinse liquid supplied to the surface of the wafer W spreads outward along the surface by the action of the centrifugal force of the rotating wafer W, and the surface of the wafer W is cleaned. Subsequently, when the rinse liquid nozzle 28 that has stopped discharging the rinse liquid is retracted, spin drying is performed in which the wafer W is rotated at a high speed to shake off the surface liquid, for example. Thereafter, the outer cup 41 and the inner cup 42 are lowered, the wafer W is unloaded by a substrate transfer means (not shown), and the developing process is finished.

Second Embodiment
FIG. 8 is a schematic plan view showing the arrangement of the two-beam interference generators in the second embodiment of the peripheral exposure apparatus according to the present invention.

  In the second embodiment, the unnecessary resist can be removed by operating the moving mechanism 34 in accordance with the width B of the unnecessary resist to move the two-beam interference product 33 in the radial direction of the wafer W. It is. That is, the two-beam interference generator 33 of the light irradiating means 30 is arranged so that the light exit port 35 is set at a position where the developer liquid film 22 is formed in the peripheral portion of the wafer W. During the process, the two-beam interference generator 33 is moved in the radial direction of the wafer W by operating the moving mechanism 34 based on a control signal from the CPU 50, so that the width B of the unnecessary resist around the wafer W is increased. In this case, the interference fringes of the laser beam are exposed.

  Thus, by moving the two-beam interference product 33 in the radial direction of the wafer W, the unnecessary resist can be accurately removed.

  In the second embodiment, the other parts are the same as those in the first embodiment, so the same parts are denoted by the same reference numerals and description thereof is omitted.

<Third Embodiment>
FIG. 9 is a schematic plan view showing an arrangement state of the two-beam interference generating body in the third embodiment of the peripheral exposure apparatus according to the present invention.

  In the third embodiment, according to the width B of the unnecessary resist, the moving mechanism 34 is operated to dispose the two-beam interference generator 33 in an inclined state with respect to the tangent line T of the wafer W, thereby removing the unnecessary resist. This is the case when it can be removed. That is, the two-beam interference generator 33 of the light irradiation means 30 is set to the tangent line T of the wafer W so that the light exit port 35 is set at a position where the developer liquid film 22 is formed in the peripheral portion of the wafer W. The laser light source 31 is irradiated with laser light during the development process, and the optical axis of the laser light transmitted through the two-beam interference generator 33 is set in the liquid film 22 as described above. This is a case where the interference fringes of the laser beam are exposed over the width B of the unnecessary resist around the wafer W by being refracted.

  In this way, by arranging the two-beam interference generator 33 in an inclined state with respect to the tangent line T of the wafer W, the interference fringes of the laser beam can be exposed in accordance with the width B of the unnecessary resist, which is unnecessary. The resist can be removed accurately.

  In the third embodiment, the other parts are the same as those in the first embodiment. Therefore, the same parts are denoted by the same reference numerals and description thereof is omitted.

<Fourth embodiment>
FIG. 10 is a schematic sectional view showing a fourth embodiment of the peripheral exposure apparatus according to the present invention.

  In the fourth embodiment, the liquid film 22 of the processing liquid is replaced with a liquid film of pure water that is a rinse liquid instead of the liquid film of the developing solution. That is, this is a case where the interference fringes of the laser beam are exposed on the peripheral portion of the surface of the wafer W during the cleaning process of the wafer W after the application of the resist.

  The light irradiation means 30 in the fourth embodiment can be incorporated in the resist coating apparatus of the resist coating unit COT. In this case, the resist coating apparatus is provided with a resist liquid supply nozzle (not shown) in place of the developer supply nozzle 24 in the development processing apparatus, and the pure water supply nozzle 60 as the processing liquid supply means is a light irradiation means. 30. The difference is that the wafer W is disposed so as to be movable in the radial direction from the center of the surface of the wafer W in a region where it does not interfere with the wafer 30. In addition, since it is the same in that it includes the driving means 21 that moves up and down, the cup 40, and the like, the same portions are denoted by the same reference numerals and description thereof is omitted.

  In the fourth embodiment, the light irradiation means 30 is set so that the light exit port 35 is set at a position slightly higher than the surface in the peripheral portion of the wafer W, that is, at a position where the liquid film 22 of the rinse liquid (pure water) is formed. In the liquid film 22, the optical axis of the laser beam transmitted through the two-beam interference generator 33 is irradiated in the liquid film 22 as described above. By refracting, the fringe of the laser beam is exposed on the periphery of the wafer W. Thereafter, the peripherally exposed wafer W is subjected to exposure processing in the exposure unit 4, and then transferred to the development processing unit DEV, where it is subjected to development processing. The insoluble part which forms is left, and unnecessary resist around the periphery of the wafer W is removed.

  In the fourth embodiment, the two-beam interference generator 33 may be moved in the radial direction of the wafer W as in the second embodiment, or the two-beam interference generation is performed as in the third embodiment. The body 33 may be disposed in an inclined state with respect to the tangent line T of the wafer W.

<Fifth Embodiment>
FIG. 11 is a schematic plan view showing a peripheral exposure apparatus according to the present invention, FIG. 12 is a perspective view showing a condensing product in the fifth embodiment, and FIG. 13 shows a state of peripheral exposure in the fifth embodiment. It is an expanded sectional view.

  The fifth embodiment is a case where the light irradiation means 70 is constituted by an ultraviolet light source, for example, an ultraviolet lamp 71 and a light collection product 72 that collects light emitted from the ultraviolet lamp 71. In this case, as shown in FIG. 12, the condensing generator 72 is formed of, for example, a quartz member, and is formed in a cylindrical base portion 74 having a light incident port 73 at the upper end and a lower portion of the cylindrical base portion 74. A reverse truncated cone portion 75 formed in a narrow taper shape downward and a light emission port 76 formed at the lower end of the reverse truncated cone portion 75 are formed.

  The light condensing product 72 of the light irradiation means 70 formed in this way is arranged in a state where the light exit port 76 is immersed in the processing liquid formed on the surface of the wafer W, for example, the liquid film 22 of the developing liquid. Therefore, as shown in FIG. 13, the optical axis emitted from the light exit port 76 by condensing the ultraviolet light emitted from the ultraviolet lamp 71 is refracted in the liquid film 22 to be more specifically the surface of the wafer W (specifically, The resist film surface) can be exposed with an increased optical contrast. As a result, the optical contrast of the irradiation light on the wafer W can be increased and the shape (tilt angle) of the resist removal portion can be improved.

  In the fifth embodiment, the other parts are the same as those in the first embodiment, and therefore the same parts are denoted by the same reference numerals and description thereof is omitted.

  In the fifth embodiment, as in the second embodiment, the light condensing product 72 may be moved in the radial direction of the wafer W so as to correspond to the width B of the unnecessary resist. In the fifth embodiment, the light exit port 76 of the light condensing product 72 may be immersed in the rinsing liquid (pure water) liquid film 22 instead of the developer liquid film 22.

<Other embodiments>
In the above embodiment, the case where the peripheral exposure apparatus (method) according to the present invention is applied to a resist coating / development processing system for a semiconductor wafer has been described. However, the present invention can also be applied to a resist coating / development processing system for an LCD glass substrate. Of course. Further, the peripheral exposure apparatus (method) according to the present invention can be used as a single apparatus without being incorporated in the system.

1 is a schematic perspective view showing a resist coating / development processing system to which a peripheral exposure apparatus according to the present invention is applied. FIG. 2 is a schematic plan view showing the resist coating / developing system. 1 is a schematic cross-sectional view showing a first embodiment of a peripheral exposure apparatus according to the present invention. FIG. 4 is a plan view of FIG. 3. It is a schematic perspective view which shows the two light beam interference production | generation body and developer supply nozzle in this invention. It is an expanded sectional view which shows a peripheral exposure state. It is a perspective view which shows the two light beam interference production | generation body in this invention. It is a schematic plan view which shows the arrangement | positioning state of the two-beam interference production | generation body in 2nd Embodiment of the peripheral exposure apparatus which concerns on this invention. It is a schematic plan view which shows the arrangement | positioning state of the two-beam interference production | generation body in 3rd Embodiment of the peripheral exposure apparatus which concerns on this invention. It is a schematic sectional drawing which shows 4th Embodiment of the peripheral exposure apparatus which concerns on this invention. It is a schematic plan view which shows the arrangement | positioning state of the condensing production | generation body in 5th Embodiment of the peripheral exposure apparatus which concerns on this invention. It is a perspective view which shows the condensing production | generation body in 5th Embodiment. It is an expanded sectional view which shows the peripheral exposure state by the light irradiation means in 5th Embodiment.

Explanation of symbols

20 Spin chuck (holding means)
21 Driving means 22 Liquid film 24 Developer supply nozzle (treatment liquid supply nozzle)
24c Linear moving mechanism 30 Light irradiation means 31 Laser light source 32 Interference fringe 33 Two-beam interference generator 34 Moving mechanism 35 Light exit 60 Pure water supply nozzle (processing liquid supply nozzle)
70 Light irradiation means 71 Ultraviolet lamp (ultraviolet light source)
72 Condensation generator 76 Light exit port W Semiconductor wafer (object to be processed)
R Resist B Resist width T Tangent θ Irradiation angle

Claims (12)

Peripheral exposure that exposes the periphery of the object to be processed over a predetermined width by relatively moving the object to be processed and the light irradiation means along the periphery of the object to be processed. In the method
The light irradiation means includes a laser light source and a two-beam interference generator that generates interference fringes by superimposing two light beams from the laser light source,
A processing liquid is supplied from the processing liquid supply means to the surface of the object to be processed, and a liquid film is formed on the surface of the object to be processed.
An optical contrast formed on the surface of the object to be processed is obtained by immersing the light exit port of the two-beam interference product in the liquid film at the periphery of the object to be processed and changing the refractive index of the emitted light. Peripheral exposure method characterized in that exposure is enhanced. The peripheral exposure method according to claim 1,
Rotate the object to be processed on a horizontal plane,
A peripheral exposure method characterized in that the processing liquid supply means is moved in the radial direction of the object to be processed in an area where it does not interfere with the two- beam interference generating body, and a liquid film is formed while supplying the processing liquid. In the peripheral exposure method according to claim 1 or 2,
A peripheral exposure method, wherein the processing solution is a developer. In the peripheral exposure method according to claim 1 or 2,
A peripheral exposure method, wherein the treatment liquid is pure water. The peripheral exposure method according to claim 1 ,
A peripheral exposure method, wherein the two-beam interference generator is exposed while moving in a radial direction of the object to be processed in a peripheral region of the object to be processed. The peripheral exposure method according to claim 1 ,
A peripheral exposure method, wherein the two-beam interference generator is exposed in a state where it is tilted with respect to a tangent to the object to be processed. Holding means for holding an object to be treated with a resist; and
Driving means for rotating the holding means on a horizontal plane;
A processing liquid supply means for supplying a processing liquid to the surface of the object to be processed to form a liquid film;
A light irradiating means for irradiating emitted light to the peripheral portion of the object to be processed,
The light irradiation means includes a laser light source and a two-beam interference generator that generates interference fringes by superimposing two light beams from the laser light source,
The optical exit formed on the object to be processed is increased by immersing the light exit port of the two-beam interference product in the liquid film at the periphery of the object to be processed and changing the refractive index of the emitted light. A peripheral exposure apparatus characterized in that the exposure is performed. The peripheral exposure apparatus according to claim 7, wherein
A peripheral exposure apparatus, wherein the processing liquid supply means is formed so as to be movable in a radial direction of an object to be processed in a region where it does not interfere with a two- beam interference generating body . The peripheral exposure apparatus according to claim 7 or 8 ,
The peripheral exposure apparatus, wherein the processing liquid supply means is a developer supply nozzle that moves in a radial direction of the object to be processed. The peripheral exposure apparatus according to claim 7 or 8 ,
The peripheral exposure apparatus, wherein the processing liquid supply means is a pure water supply nozzle that moves in a radial direction of the object to be processed. The peripheral exposure apparatus according to claim 7 , wherein
A peripheral exposure apparatus, wherein the two-beam interference generator is formed so as to be movable in a radial direction of the object to be processed in a peripheral region of the object to be processed. The peripheral exposure apparatus according to claim 7 , wherein
A peripheral exposure apparatus, wherein the two-beam interference generator is disposed in an inclined state with respect to a tangent line of an object to be processed.

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