JP2006093623A - Exposure equipment and exposure method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide exposure equipment and an exposure method by which a foaming resist is easily and securely recovered. <P>SOLUTION: The exposure equipment includes: an exposure head 7 which irradiates light to peripheral portions of a wafer 6 provided with a processing film; and exposes the processing film, and an exhaust means 12 at a down side of the wafer 6, which includes two exhaust outlets 11 into which the foaming resist produced by exposure is absorbed, wherein one exhaust outlet 11a is arranged outside the wafer 6, while the other exhaust outlet 11b is arranged inside the wafer 6, and the foaming resist in an unsettled flying state is efficiently exhausted by the two exhaust outlets 11. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an exposure apparatus and an exposure method for performing exposure by irradiating light to an object to be processed so that the foamed resist can be easily and reliably collected.

  In the semiconductor manufacturing process, a photoresist film is formed on the surface of a semiconductor wafer that is an object to be processed, a fine circuit pattern of a mask is transferred to the photoresist film by photolithography, and this is finely developed by etching or the like after development. Has been processed. When a photoresist film is formed on a wafer surface, generally, a photoresist solution is dropped onto the central portion of the wafer surface, and the photoresist solution dripped by rotating the wafer at a high speed is applied to the entire surface by centrifugal force. A coating method is used.

  When a photoresist film is formed by spin coating, the photoresist film is formed over the entire surface of the wafer. If the photoresist film is formed on the entire surface, the photoresist film at the peripheral portion is mechanically broken during handling during transportation in a subsequent process, and scattered as particles. For this reason, after the photoresist film is formed, the photoresist film at the peripheral edge of the wafer is removed in advance by a peripheral exposure apparatus.

  As an exposure apparatus for removing the photoresist film on the peripheral edge of the wafer, the photoresist film on the peripheral edge is exposed to light such as ultraviolet rays while rotating the wafer, and the photoresist film on the peripheral edge is removed during development. (For example, refer to Patent Document 1 and Patent Document 2 below).

  When exposing a photoresist film, if the illuminance is high, bubbles may be generated inside the photoresist film due to a rapid temperature rise due to light energy or a chemical reaction due to ultraviolet rays, and may be scattered as a foamed resist. The scattered foamed resist may become particles and adhere to the surface of the wafer, resulting in a residual development during the development process. In a clean room or the like, the fluid is down-flowed to prevent particles from adhering to the wafer surface. However, there is a possibility that the particles may wrap around the chuck and contaminate the apparatus itself.

  For this reason, the technique disclosed in Patent Document 1 discloses that the foamed resist is exhausted by providing one exhaust port in the vicinity of the exposure head. In the technique disclosed in Patent Document 2, it is shown that the foamed resist is exhausted to one exhaust port by blowing an inert gas.

JP-A-2-194619 JP 2003-218007 A

  Depending on the environment in which the exposure equipment is installed, the exposure processing status, etc., the scattering direction and amount of the foamed resist are not constant, and even if a single exhaust port is provided, the scattered foamed resist will be exhausted sufficiently. The situation is not reached. By blowing the inert gas and transporting the foamed resist to the exhaust port, it is possible to exhaust the foamed resist while suppressing the scattering to some extent, but exhausting the foamed resist that wraps around the underside of the chuck etc. It was not possible to suppress the contamination of the device.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an exposure apparatus and an exposure method that can efficiently evacuate a foamed resist that scatters while suppressing the adhesion to the apparatus.

In order to achieve the above object, a first aspect of the present invention comprises an exposure means for exposing a processing film by irradiating light to a peripheral portion of a target object provided with the processing film, and a foamed resist generated by the exposure. An exposure apparatus having an exhaust means having a plurality of exhaust ports through which air is sucked.
In the first aspect, it is possible to efficiently exhaust the foamed resist that is not scattered by the plurality of exhaust ports.

According to a second aspect of the present invention, in the first aspect, the exhaust port is disposed on the opposite side of the exposure unit with the object to be processed interposed therebetween, and at least one exhaust port is located outside the object to be processed. An exposure apparatus is characterized in that one exhaust port is positioned inside the object to be processed.
In the second aspect, the foamed resist on the back side of the object to be processed can be easily exhausted, and the foamed resist can be exhausted regardless of the shape of the object to be processed.

According to a third aspect of the present invention, in the first aspect, the exhaust port is disposed on a side portion of the object to be processed at a position corresponding to the exposure unit, and the exhaust port is disposed on both sides of the object to be processed. In the exposure apparatus,
In the third aspect, the foamed resist on the back side of the object to be processed can be easily exhausted.

According to a fourth aspect of the present invention, there is provided an exposure apparatus according to any one of the first to third aspects, wherein the exhaust port has an inclined surface.
In the fourth aspect, the area of the exhaust port can be maximized with a small width.

According to a fifth aspect of the present invention, in any one of the first to fourth aspects, a suction drive unit that sucks the foamed resist from the exhaust port is provided, and a recovery unit that collects the sucked foamed resist is provided. An exposure apparatus is provided with supply means for supplying the recovered fluid to the surface of the object to be processed by the driving force of the suction drive means and guiding it to the exhaust port.
In the fifth aspect, the foamed resist is recovered in the system, and the foamed resist on the object to be processed is guided to the exhaust port by the supply means. In addition, the foamed resist on the object can be exhausted.

A sixth aspect of the present invention is characterized in that the processing film is exposed by irradiating light to the peripheral portion of the target object provided with the processing film, and the foamed resist generated by the exposure is collected at a plurality of exhaust ports. The exposure method is as follows.
In the sixth aspect, the scattered foamed resist that is not constant can be efficiently exhausted by the plurality of exhaust ports.

  FIG. 1 is a schematic side view of an exposure apparatus according to the first embodiment of the present invention, FIG. 2 is a schematic perspective view of the exposure apparatus according to the first embodiment of the present invention, and FIG. FIG. 4 shows a perspective view of the exhaust means, and FIG. 5 shows a plan view explaining the relationship between the orientation flat and the exhaust port.

  A spin chuck 2 constituting the exposure apparatus 1 is provided in a chamber (not shown), and a disk-shaped table 3 is provided above the spin chuck 2. In the spin chuck 2, the table 3 is rotationally driven by a spin motor 4. A suction hole 5 is formed on the upper surface of the table 3 of the spin chuck 2, and the suction hole 5 is connected to a vacuum device (not shown). The wafer 6 that is the object to be processed is placed on the table 3 and the suction holes 5 are brought into a vacuum state, whereby the wafer 6 is sucked onto the table 3. The spin chuck 2 is movable to an arbitrary position by a driving device (not shown).

  An exposure head 7 as an exposure unit is provided above the table 3 at a portion corresponding to the periphery of the wafer 6 attracted to the table 3, and light is emitted from the exposure head 7 on the upper surface of the periphery of the wafer 6 attracted to the table 3. Is exposed to expose the upper surface of the periphery of the wafer 6. The exposure head 7 has an irradiation part made of optical glass or the like, and the exposure head 7 is connected to a light source 8 such as a mercury lamp or a xenon lamp via an optical transmission path. Light such as ultraviolet rays from the light source 8 is transmitted to the exposure head 7 through the transmission path, and the upper surface of the periphery of the wafer 6 adsorbed on the table 3 is irradiated with light. The exposure head 7 is supported by a support flange 9 and can be moved to an arbitrary position in a horizontal plane by a horizontal movement mechanism (not shown).

  Exhaust means 12 having two exhaust ports 11 is provided on the opposite side of the exposure head 7 (under the wafer 6) with the wafer 6 interposed therebetween. Foamed resist (details will be described later) generated by exposing the peripheral edge is sucked into the two exhaust ports 11 and exhausted. The two exhaust ports 11 are each formed in a rectangular shape, and the longitudinal direction of the exhaust port 11 extends in a direction parallel to the tangent to the table 3. Various dimensions of the exhaust port 11 are set depending on the size of the apparatus and the like, and for example, it is formed in a rectangular shape of 1 cm × 3 cm.

  Note that the shape of the exhaust port 11 is not limited to a rectangular shape, and an arc shape or a round hole-shaped exhaust port along the outer periphery of the wafer 6 can also be applied, and clogging occurs when the suction force is increased. It is possible to make the exhaust port as small as possible. Moreover, the number of the exhaust ports 11 is not limited to two, and can be provided at a plurality of three or more locations.

  One exhaust port 11 a of the exhaust unit 12 is disposed outside the wafer 6, and the other exhaust port 11 b is disposed inside the wafer 6. For this reason, the foamed resist on the back side of the wafer 6 can be easily exhausted. In addition, although the orientation flat 6a is provided on the wafer 6, as shown in FIG. 5, when the exhaust means 12 and the orientation flat 6a face each other due to the rotation of the wafer 6, the exhaust outlet 11b located inside the wafer 6 has a wafer outlet. 6, the foamed resist is exhausted from the exhaust port 11b. Therefore, regardless of the shape of the wafer 6, the exhaust port 11 is maintained in a state positioned below the peripheral edge, and the foamed resist can be exhausted regardless of the shape of the wafer 6.

  Further, the exhaust ports 11a and 11b are inclined so that the long sides facing each other are lowered. For this reason, it is possible to minimize the surface parallel to the wafer 6 and to secure the widest opening area facing the wafer 6.

  As shown in FIGS. 1 and 2, a purge nozzle 13 is provided as supply means for supplying a purge fluid toward the surface of the wafer 6 and guiding the foamed resist to the exhaust port 11. The exhaust means 12 and the purge nozzle 13 are connected by a circulation path 14 so that the fluid exhausted from the exhaust port 11 is not released to the outside environment. The circulation path 14 is provided with a filter means 15 as a collecting means for capturing the foamed resist exhausted from the exhaust port 11 and a suction drive means 16 for sucking the foamed resist from the exhaust port 11.

  That is, the foamed resist is sucked from the exhaust port 11 by driving the suction drive means 16, and after the foamed resist is captured by the filter means 15, the fluid from which the foamed resist has been removed is supplied from the purge nozzle 13 to the surface of the wafer 6. . The foamed resist captured by the filter means 15 is discarded to the outside in a predetermined cycle to prevent the filter means 15 from being clogged.

  For this reason, the foamed resist is recovered in the system. For this reason, the foamed resist is not discharged to the external environment, and the exposure apparatus is environmentally friendly. Further, since the foamed resist on the wafer 6 is guided to the exhaust port 11 by the purge nozzle 13, the foamed resist on the wafer 6 can be surely exhausted.

  In addition, without providing the circulation path 14, the filter means 15, and the suction drive means 16, it is also possible to discharge the foamed resist from the exhaust port 11 together with general factory exhaust.

  An exposure process for the peripheral portion of the wafer 6 by the exposure apparatus 1 will be described. FIG. 6 shows a side view for explaining the situation at the time of exposure.

  The exposure process for the peripheral portion of the wafer 6 may be performed after the photoresist film is formed on the surface of the wafer 6 and before the development process. For example, it can be carried out in a pre-bake process for improving the adhesion of the photoresist film, a process before and after the mask pattern process, a process immediately before the development process, and the like.

  The wafer 6 coated with the photoresist film is loaded and placed on the upper surface of the table 3, and the wafer 6 is sucked to the table 3 by making the suction holes 5 in a vacuum state. At this time, the wafer 6 is aligned with the center of the spin chuck 2. The exposure head 7 is moved to a position at a predetermined distance directly above the peripheral edge of the wafer 6. In this state, the wafer 6 is rotated by rotating the spin motor 4, and at the same time, light is transmitted from the light source 8 to the exposure head 7, and light is irradiated from the exposure head 7 to the peripheral portion of the wafer 6.

  Thereby, as shown in FIG. 6, the photoresist film 20 is exposed along the peripheral edge. The width of light irradiation is set to a width that may cause the hand portion to come into contact with and peel off during handling of the wafer 6. By appropriately moving the exposure head 7, the peripheral edge photoresist film 20 is exposed over the entire circumference of the wafer 6 including the orientation flat.

  Upon exposure of the peripheral edge, as shown in FIG. 6, a solvent or the like is vaporized from the resist portion irradiated with light having high illuminance due to a temperature rise or chemical reaction, and bubbles 21 are generated. Become scattered. The scattered foamed resist 22 is guided to the exhaust port 11 by the purge fluid from the purge nozzle 13 and sucked into the exhaust port 11. For this reason, it is possible to reliably prevent the scattered foamed resist 22 from adhering to the surface of the wafer 6.

  Further, there may be a case where the foamed resist 22 wraps around the back side of the wafer 6 such as when the clean fluid is flowing down from above the wafer 6. Even when the foamed resist 22 wraps around the back side of the wafer 6, it is exhausted from the exhaust port 11b located on the back side of the wafer 6, and the foamed resist 22 does not adhere to the apparatus (spin chuck 2, spin motor 3, etc.). .

  Therefore, even the foamed resist 22 whose scattering direction is not determined can be surely exhausted by the exhaust means 12 having the two exhaust ports 11 disposed on the inner side and the outer side of the wafer 6 below the wafer 6. The pattern defects due to the adhesion of particles can be reduced, and the exposure apparatus 1 can be cleaned.

  The foamed resist 22 exhausted from the exhaust port 11 is sent to and captured by the filter means 15 by driving the suction drive means 16, and the fluid from which the foamed resist 22 has been removed is supplied from the purge nozzle 13 to the surface of the wafer 6.

  A second embodiment of the present invention will be described based on FIG. FIG. 7 shows a schematic side view of an exposure apparatus according to the second embodiment of the present invention. Note that the same components as those in the exposure apparatus of the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  As shown in the drawing, the exposure apparatus 31 of the second embodiment is different from the first embodiment in the arrangement state of the exhaust means 12. That is, an exhaust unit 12 having two exhaust ports 11 is provided on the side of the wafer 6 at a position corresponding to the exposure head 7, and the exhaust port 11 of the exhaust unit 12 is oriented in a direction parallel to the surface of the wafer 6. The openings are opened so that the opening surfaces intersect. One exhaust port 11 a of the exhaust unit 12 is disposed on the upper side of the wafer 6, and the other exhaust port 11 b is disposed on the lower side of the wafer 6. That is, the two exhaust ports 11 of the exhaust unit 12 are arranged on both sides of the wafer 6.

  The foamed resist 22 (see FIG. 6) generated by exposing the peripheral edge of the wafer 6 is sucked into the two exhaust ports 11 disposed above and below the wafer 6 and exhausted. The two exhaust ports 11 are each formed in a rectangular shape, and the longitudinal direction of the exhaust port 11 extends in a direction parallel to the tangent to the table 3. Various dimensions of the exhaust port 11 are set depending on the size of the apparatus and the like, and for example, it is formed in a rectangular shape of 1 cm × 3 cm.

  Similarly to the first embodiment, the exhaust ports 11a and 11b are inclined surfaces such that the long sides facing each other are lowered. Therefore, it is possible to minimize the surface intersecting with the direction parallel to the disk surface of the wafer 6 and to secure the widest opening area of the surface intersecting with the direction parallel to the surface of the wafer 6.

  When the peripheral portion is exposed, the foamed resist 22 is scattered. The scattered foamed resist 22 is guided to the exhaust port 11 by the purge fluid from the purge nozzle 13 and sucked into the exhaust port 11. For this reason, it is possible to reliably prevent the scattered foamed resist 22 from adhering to the surface of the wafer 6.

  In addition, the foamed resist 22 may be scattered toward the outside of the wafer 6 due to the influence of the centrifugal force of the wafer 6 due to rotation. Even when the foamed resist 22 scatters toward the outside of the wafer 6, the foamed resist 22 is exhausted from the exhaust port 11 facing the wafer 6 from the outside in the circumferential direction, and the foamed resist 22 is removed from the apparatus (a chamber (not shown) or spin chuck 2). , Spin motor 3 etc.).

  Therefore, even the foamed resist 22 whose scattering direction is not determined can be surely exhausted by the exhaust means 12 having the two exhaust ports 11 arranged on both sides of the wafer 6 with the side of the wafer 6 interposed therebetween. The pattern defects due to the adhesion of particles can be reduced, and the exposure apparatus 1 can be cleaned.

1 is a schematic side view of an exposure apparatus according to a first embodiment of the present invention. 1 is a schematic perspective view of an exposure apparatus according to a first embodiment example of the present invention. It is a top view explaining the relationship between an exhaust port and a wafer. It is a perspective view of an exhaust means. It is a top view explaining the relationship between an orientation flat and an exhaust port. It is a side view explaining the condition at the time of exposure. It is a schematic side view of the exposure apparatus which concerns on the 2nd Embodiment example of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1,31 Exposure apparatus, 2 Spin chuck, 3 Table, 4 Spin motor, 5 Suction hole, 6 Wafer, 7 Exposure head, 8 Light source, 9 Flange, 11 Exhaust port, 12 Exhaust means, 13 Purge nozzle, 14 Circulation path, 15 Filter means 16 Suction drive means 20 Photoresist film 21 Bubbles 22 Foam resist

Claims (6)

  An exposure unit that exposes the processing film by irradiating light to a peripheral portion of the object to be processed provided with the processing film, and an exhaust unit having a plurality of exhaust ports into which the foamed resist generated by the exposure is sucked. An exposure apparatus.   2. The exhaust port according to claim 1, wherein the exhaust port is disposed on the opposite side of the exposure unit with the object to be processed interposed therebetween, at least one exhaust port is located outside the object to be processed, and at least one exhaust port is located inside the object to be processed. An exposure apparatus characterized by being located in   2. The exposure apparatus according to claim 1, wherein the exhaust port is disposed on a side portion of the object to be processed at a position corresponding to the exposure unit, and the exhaust port is disposed on both sides of the object to be processed.   4. An exposure apparatus according to claim 1, wherein the exhaust port has an inclined surface.   The suction drive means for sucking the foamed resist from the exhaust port according to any one of claims 1 to 4, further comprising a recovery means for recovering the sucked foam resist, wherein the fluid after the foamed resist is recovered An exposure apparatus comprising supply means for supplying to the surface of an object to be processed by a driving force and guiding it to an exhaust port.   An exposure method comprising exposing a processing film by irradiating light to a peripheral portion of an object to be processed provided with the processing film, and collecting the foamed resist generated by the exposure at a plurality of exhaust ports.

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