JP2006278389A - Peripheral exposure device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To expose the peripheral region of an object to be exposed with significantly reduces the adverse effects on the object to be exposed, without accompanying wasteful power consumption, realizing smaller size and simplicity. <P>SOLUTION: The peripheral exposure device comprises an XY stage 2 for bearing a substrate 1, on which a resist is applied, a rotary table 3 for bearing the XY stage 2, a light source 4 for peripheral exposure which performs peripheral exposure on the substrate 1, a slider 5 for holding the light source 4 for peripheral exposure, an illumination photometer 6 for detecting the output light intensity of the light source 4, a DC power supply 7 for supplying a drive current to the light source 4, and a temperature control mechanism 8 for controlling the temperature of the light source 4. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a peripheral exposure apparatus for exposing a predetermined position around an object to be exposed such as a glass substrate for liquid crystal, a semiconductor wafer, and a photosensitive film.

  2. Description of the Related Art Conventionally, peripheral exposure apparatuses for exposing a predetermined peripheral position of an object to be exposed such as a liquid crystal glass substrate, a semiconductor wafer, and a photosensitive film have been provided and put into practical use.

  When a wiring pattern is formed on a substrate such as a liquid crystal display panel or a semiconductor wafer, first, a resist is applied to the entire surface of the substrate, and a wiring pattern is manufactured by patterning into a desired shape by photolithography. The exposure position of the mask pattern is determined so that a strip-shaped blank having a width of about several millimeters is produced in the peripheral portion.

  For this reason, when a positive resist is used in the photolithography process, an unexposed resist remains in a strip shape around the substrate after the development process. Not only is this residual resist unnecessary, but it becomes dust in a later manufacturing process, which becomes a major problem as one factor in reducing the throughput. Therefore, it is necessary to remove unnecessary resist regions around the substrate by exposure and development.

  Considering such problems, conventionally, for example, apparatuses disclosed in Patent Document 1 and Patent Document 2 are known as peripheral exposure apparatuses for rectangular substrates.

In the apparatuses described in Patent Document 1 and Patent Document 2, one exposure lamp is used as one light source for exposing one portion of the peripheral portion of the substrate, and a reflecting mirror, a lens group, and a wavelength cut filter are provided therein. The substrate peripheral portion can be exposed by moving the substrate or the light source while irradiating light emitted from the substrate to the substrate peripheral portion. In addition, cooling of the light source is achieved by air cooling, and warm air generated therefrom is exhausted by a blower.
JP-A-11-154039 Japanese Patent Laid-Open No. 5-190448

  In the apparatus described in Patent Literature 1 and Patent Literature 2, since one discharge lamp is used as one light source, the following problems occur.

  Because the discharge lamp's standby time and warm-up time are long, it is necessary to keep the discharge lamp lit even when peripheral exposure is not performed, which shortens the life of the discharge lamp and increases power consumption more than necessary. Workability deteriorates with frequent replacement of the discharge lamp.

  Since a discharge lamp generates a large amount of heat, a large blower is required for cooling.

  Since mercury is used inside the discharge lamp, the health of workers when the discharge lamp is damaged and the environmental load when processing the discarded discharge lamp are large.

  The structure of a discharge lamp is large, and the devices related to it are inevitably large.

  Since the discharge lamp has a wide wavelength distribution band of output light and emits light even in a wavelength band not related to photosensitivity, a lot of power is wasted.

  In the discharge lamp, most of the electric energy is converted into heat energy, so that more power is wasted.

  Since the output light of the discharge lamp includes infrared rays, not only the exposure but also the thermal effect is exerted on the substrate.

  Since the discharge lamp has a short life, it needs to be replaced frequently.

  Since the discharge lamp has a wide wavelength distribution band of the output light and is irradiated with light in a wavelength band not related to photosensitivity, an optical load is applied to the substrate, and in order to prevent this, an unnecessary wavelength band is applied to the irradiated part. It is necessary to provide a filter that cuts light so that it is not irradiated.

  The present invention has been made in view of the above-described problems, and can achieve downsizing and simplification, can greatly reduce the adverse effect on the exposure object, and can perform exposure without wasteful power consumption. An object of the present invention is to provide a peripheral exposure apparatus capable of exposing a peripheral region of an object.

  In the peripheral exposure apparatus of the present invention, a peripheral exposure light source including a light emitting diode that emits ultraviolet light is disposed in correspondence with a predetermined peripheral position of an exposure object.

  Here, the peripheral exposure light source may include a plurality of light emitting diodes arranged in a state of maintaining a predetermined relative relationship, or may include a plurality of light emitting diodes arranged in a matrix. May be. Further, the peripheral exposure light source may irradiate light emitted from the light emitting diode directly to a predetermined peripheral position of the exposure target.

  Furthermore, a cooling water generating device for supplying cooling water for cooling the light emitting diode, a water temperature detecting device for detecting the temperature of the cooling water immediately after cooling the light emitting diode, and the temperature of the cooling water immediately after cooling the light emitting diode are maintained at a predetermined temperature. Thus, a water temperature control device that controls the cooling water generating device may be further included.

  Furthermore, the light emitting diode is energized in response to an instruction to expose a predetermined position around the exposure object and emits light in response to an instruction not to expose the predetermined position around the exposure object. An energization control device that prevents energization of the diode may be further included.

  In the peripheral exposure apparatus of the present invention, a peripheral exposure light source including a light emitting diode that emits ultraviolet light is arranged corresponding to a predetermined peripheral position of an exposure object, so that downsizing and simplification can be achieved. This can be realized, the adverse effect on the exposure object can be greatly reduced, and the peripheral area of the exposure object can be exposed without wasteful power consumption.

  In the case where the peripheral exposure light source includes a plurality of light emitting diodes arranged in a state in which a predetermined relative relationship is maintained, light intensity leveling can be realized without using a special mechanism. When the peripheral exposure light source includes a plurality of light emitting diodes arranged in a matrix, it is possible to lengthen the time during which the exposure target is irradiated with light and increase the light energy applied to the exposure target. . When the peripheral exposure light source directly irradiates light emitted from the light emitting diode to a predetermined position around the exposure target, it is possible to achieve downsizing and simplification.

  Also, a cooling water generating device that supplies cooling water for cooling the light emitting diode, a water temperature detecting device that detects the temperature of the cooling water immediately after cooling the light emitting diode, and the temperature of the cooling water immediately after cooling the light emitting diode are maintained at a predetermined temperature. Thus, when the water temperature control device for controlling the cooling water generating device is further included, the temperature of the light emitting diode can be kept substantially constant, and the exposure quality can be stabilized.

  Further, the light emitting diode is energized in response to an instruction to expose a predetermined position around the exposure object, and the light emitting diode is responded to an instruction not to expose the predetermined position around the exposure object. In the case of further including an energization control device that prevents energization of the light source, unnecessary power consumption can be prevented and the life of the light emitting diode can be extended.

  The present invention can realize downsizing and simplification, can significantly reduce the adverse effect on the exposure object, and can expose the peripheral area of the exposure object without wasteful power consumption. Has a unique effect.

  Further, by turning on only during exposure, the life of the light emitting diode can be extended, the power consumption can be minimized, and workability such as replacement of the light emitting diode can be improved.

  Since the amount of heat generated by the light emitting diode can be reduced, cooling with a small chiller is possible.

  Since the light emitting diode does not use mercury, it is possible to eliminate the health damage and environmental burden on the worker.

  Since the light emitting diode is small and light, the device can be downsized.

  Since the light-emitting diode has a narrow wavelength distribution band, irradiation can be performed only in the wavelength band related to exposure (exposure), and wasteful power consumption can be prevented.

  Since the light emitting diode has high luminous efficiency, generation of heat energy can be suppressed, and consequently power consumption can be suppressed.

  Since the output light of the light emitting diode does not include infrared rays, no heat load is applied to the object to be processed.

  Since the light emitting diode has a long life, the replacement cycle can be lengthened and the number of replacement operations can be reduced.

  The output light of the light emitting diode has a narrow wavelength distribution band, can irradiate only the wavelength band related to exposure (exposure), eliminates optical stress on the object to be processed, and cuts unnecessary wavelength band Therefore, the configuration can be simplified without the need for a filter.

  Embodiments of a peripheral exposure apparatus according to the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 is a perspective view schematically showing one embodiment of a peripheral exposure apparatus of the present invention.

  This peripheral exposure apparatus is applied to peripheral exposure of a liquid crystal panel.

  This peripheral exposure apparatus includes an XY stage 2 that supports a substrate 1 coated with a resist, a rotary table 3 that supports the XY stage 2, a peripheral exposure light source 4 that performs peripheral exposure on the substrate 1, and a peripheral exposure light source. 4, a slider 5 that holds 4, an illuminance meter 6 that detects the output light intensity of the peripheral exposure light source 4, a DC power supply 7 that supplies a drive current to the peripheral exposure light source 4, and the temperature of the peripheral exposure light source 4. And a temperature control mechanism 8.

  Examples of the substrate 1 include a glass substrate, a substrate made of another material, a semiconductor wafer, and a film. Various shapes can be used.

  The XY stage 2 moves the substrate 1 two-dimensionally, and the rotary table 3 rotates the substrate 1 together with the XY stage 2.

  The peripheral exposure light source 4 includes a light emitting diode (UV-LED) 4a that emits ultraviolet rays as a light source, and includes a bracket 4b, a light shielding mask 4c (see FIG. 2), and the like. For example, as shown in FIG. 2, the light shielding mask 4c has a rectangular window hole, and the irradiation area of the substrate 1 by the UV-LED 4a can be made rectangular to improve the dimensional accuracy of the exposure area. FIG. 3 shows that the exposure area becomes circular when the light shielding mask is not used. Therefore, by comparing with FIG. 3, it can be seen that the dimensional accuracy of the exposure area can be increased in the case of FIG.

  The slider 5 reciprocates the peripheral exposure light source 4 in a direction orthogonal to the moving direction of the substrate 1 in a predetermined direction by the XY stage 2.

  The illuminometer 6 receives the output light of the peripheral exposure light source 4 at the movement limit position of the peripheral exposure light source 4 by the slider 5 and supplies an intensity detection signal to the DC power source 7.

  The DC power supply 7 supplies a driving voltage or current to the peripheral exposure light source 4 so that a predetermined output light intensity can be obtained. Preferably, the drive voltage or current is controlled so that the UV-LED 4a emits light only during exposure and the exposure conditions are changed as necessary. In order to perform such control, a drive voltage or current is previously stored as data for each product type in a control device (computer, programmable logic array, etc.) having an input function, storage function, comparison operation function, operation command function, etc. It is preferable to register.

  In addition, it is preferable to periodically measure the output light intensity with the illuminometer 6, supply the output light intensity measurement value to the control device, and calculate the appropriate irradiation state of the UV-LED 4a. Even in this case, stable exposure quality can be realized.

  The temperature control mechanism 8 includes a chiller 8a for generating cooling water, a cooling water flow path 8b for supplying cooling water to the bracket 4b to cool the UV-LED 4a, and returning it to the chiller 8a again, and a cooling water flow path 8b. A valve 8c, a flow meter 8d, a water pressure meter 8e, and a water temperature sensor 8f provided at predetermined positions are provided. The water temperature sensor 8f is provided immediately downstream of the bracket 4b and supplies a temperature detection signal to the chiller 8a to control the operation of the chiller 8a.

  In addition, the substrate 1 is carried in and out by a substrate transfer robot (not shown), a shuttle transfer mechanism, a roller conveyor, or the like, or manually by an operator.

  Further, it is preferable to provide an L-shaped alignment guide (not shown) or a pin-type guide that contacts only three points on the L-shape. When the position of the substrate 1 supplied to the XY stage 2 is shifted, the guide The substrate 1 can be pressed against and aligned.

  The operation of the peripheral exposure apparatus having the above-described configuration is as follows.

  When the resist-coated substrate 1 is loaded and positioning is performed by driving the XY stage 2 and the rotary table 3, the peripheral exposure light source 4 is positioned by the slider 5 so as to face the peripheral position to be exposed. This completes the preparation for the peripheral exposure.

  Thereafter, the substrate 1 is moved in one direction by the XY stage 2, and the peripheral exposure light source 4 is operated by the DC power source 7, whereby unnecessary resist in the peripheral portion can be exposed along one side of the substrate 1. .

  Next, the XY stage 2 and the rotary table 3 are operated, and the slider 5 is operated to position the peripheral exposure light source 4 so as to face the peripheral position to be exposed on the other side. The unnecessary resist in the peripheral portion can be exposed along the side.

  Similarly, the unnecessary resist in the peripheral portion can be exposed along all the sides of the substrate 1.

  If the above processing is performed, the peripheral exposure of all four sides of the rectangular substrate 1 can be performed, but only one of the sides can be exposed, and in addition to the peripheral exposure, the exposure to the inside of the substrate is possible. It is also possible to perform. When this function is incorporated in another apparatus, no side may be exposed.

  The peripheral exposure light source 4 may be arranged on the entire shape to be exposed in advance or a shape obtained by dividing the shape, and exposure may be performed by irradiating the stage for a required time.

  It is also possible to operate the XY stage 2, the rotary table 3, and the slider 5 during the exposure of the unnecessary resist portion, and perform the peripheral exposure according to the shape having the unevenness on the exposure end face.

  FIG. 4 is a perspective view schematically showing another embodiment of the peripheral exposure apparatus of the present invention.

  This peripheral exposure apparatus is applied to peripheral exposure of a semiconductor wafer.

  The edge exposure apparatus differs from the edge exposure apparatus in FIG. 1 in that the XY stage 2 is omitted, an L-shaped alignment guide, or an end face detection apparatus instead of a pin-type guide that contacts only three points on the L-shape. 9 is only a point where the shape of the window hole of the light shielding mask 4c is set to a slit instead of a rectangle.

  Therefore, in this embodiment, peripheral exposure can be achieved by irradiating the light from the peripheral exposure light source 4 while rotating the circular substrate 1.

  In each of the above embodiments, the peripheral exposure light source 4 is stationary and the substrate 1 is moved to achieve peripheral exposure. However, the substrate 1 is stationary and the peripheral exposure light source 4 is moved. By means of this, it is possible to achieve edge exposure.

  It is also possible to employ a plurality of peripheral exposure light sources 4.

  In each of the above embodiments, the surface for supporting the substrate 1 is set to be a flat surface, but it is possible to employ a configuration in which a plurality of support pins are provided to support the substrate 1, When the substrate 1 is rectangular, it is possible to hold one side of the substrate 1 and hold the substrate 1 in a horizontal state or a vertical state.

  Further, in each of the above embodiments, the DC power supply 7 can be controlled to turn on / off the UV-LED 4a. In this case, as shown in FIG. 5, based on the ON time and the OFF time. , Exposure can be achieved intermittently.

  In each of the above embodiments, three UV-LEDs 4a are arranged in a straight line, but a different number of UV-LEDs 4a can be arranged. It is also possible to arrange the UV-LEDs 4a in a plurality of rows and columns {see FIGS. 6 and 7}. The peripheral exposure light source 4 shown in FIG. 6 has UV-LEDs 4a arranged in a grid pattern, and the peripheral exposure light source 4 shown in FIG. 7 has UV-LEDs 4a arranged in a staggered pattern.

  In these cases, the time during which the substrate 1 is irradiated with light can be lengthened, and the light energy applied to the substrate 1 can be increased (see FIG. 8; however, FIG. The illuminance distribution is shown when arranged in 3 rows and 2 columns.)

  Moreover, the area which can be exposed can be expanded by setting appropriately the space | interval of adjacent UV-LED4a.

  This point will be further described.

In realizing peripheral exposure by completely exposing the resist applied to the substrate 1, resist sensitivity (mJ / cm2), UV-LED illuminance (mW / cm2), exposure speed (mm / sec), and irradiation Four parameters of area width (mm) are related.
Here, the resist sensitivity (mJ / cm 2) is a value indicating how much light energy is applied to the resist applied to the substrate 1 to be exposed.

The illuminance (mW / cm 2) of the UV-LED is the amount of light energy per unit area on the substrate surface of the light irradiated from the UV-LED (the light in the wavelength band where the resist is exposed).
The exposure speed (mm / sec) is a speed at which the UV-LED passes over the substrate.
The irradiation area width (mm) is the width of the area on the substrate illuminated by the irradiation light (dimension in the passing direction).
It is.

  In order to achieve the peripheral exposure by correctly exposing the peripheral portion of the substrate 1, it is necessary to satisfy the following conditions.

Irradiation area width (mm) / {resist sensitivity (mJ / cm2) / UV-LED illuminance (mW / cm2)} ≧ exposure speed (mm / sec)
However, normally, parameters other than “UV-LED illuminance” are determined first from the usage conditions. Therefore, what is necessary is just to determine the illumination intensity of UV-LED so that the said conditional expression may be satisfied.
As shown in FIG. 9, the light emitted from the UV-LED has a normal distribution with the highest illuminance at the center. 9 and the following figures, numerals 1 to 5 indicate illuminance, and the illuminance at which the resist is correctly exposed is set to 3 or more.

  Therefore, when there is no overlap in irradiation of individual UV-LEDs, as shown in FIG. 9, the illuminance distribution of any UV-LED does not change at all.

  If the relative positions of the UV-LEDs are set so that the portions with the illuminance of 1 overlap each other, the lowest illuminance between the UV-LEDs becomes 2 (see FIG. 10). However, with this illuminance 2, the resist cannot be correctly exposed.

  If the relative position of the UV-LEDs is set so that the portion with illuminance 1 overlaps the portion with illuminance 2, the lowest illuminance between the UV-LEDs is 3 (see FIG. 11). Therefore, the resist can be correctly exposed in the entire range between both UV-LEDs. That is, as compared with FIG. 9, significant leveling of illuminance can be achieved.

1 is a perspective view schematically showing an embodiment of a peripheral exposure apparatus of the present invention. It is a schematic perspective view which shows the relationship between a light shielding mask and an irradiation area. It is a schematic perspective view which shows the irradiation area when a light shielding mask does not exist. It is a perspective view which shows schematically other embodiment of the peripheral exposure apparatus of this invention. It is a perspective view which shows an example of intermittent exposure schematically. It is the schematic which shows the light source for edge exposure which arranged UV-LED in the grid | lattice-like 4 rows 4 columns. It is the schematic which shows the light source for edge exposure which arranged UV-LED in zigzag form. It is the schematic which shows the illumination intensity distribution of the light source for peripheral exposure which arranged UV-LED in the grid | lattice-like 3 rows 2 columns. It is the schematic which shows the illumination intensity distribution by two UV-LED. It is the schematic which shows the illumination intensity distribution of the state which accumulated the outermost edge part of the irradiation range of two UV-LED. It is the schematic which shows the illumination intensity distribution of the state which set the space | interval of both UV-LED so that the illumination intensity between two UV-LED may become the illuminance which can be photosensitized.

Explanation of symbols

1 Substrate 4 Peripheral exposure light source 4a UV-LED
8a Chiller 8f Water temperature sensor

Claims (6)

A peripheral exposure apparatus comprising a peripheral exposure light source (4) including a light emitting diode (4a) that emits ultraviolet light in correspondence with a predetermined peripheral position of the exposure object (1). The peripheral exposure apparatus according to claim 1, wherein the peripheral exposure light source (4) includes a plurality of light emitting diodes (4a) arranged in a state in which a predetermined relative relationship is maintained. The peripheral exposure apparatus according to claim 1, wherein the peripheral exposure light source (4) includes a plurality of light emitting diodes (4a) arranged in a matrix. A cooling water generating device (8a) for supplying cooling water for cooling the light emitting diode (4a), a water temperature detecting device (8f) for detecting the temperature of the cooling water immediately after cooling the light emitting diode, and the cooling water immediately after cooling the light emitting diode. The peripheral exposure apparatus according to claim 1, further comprising a water temperature control device that controls the cooling water generating device (8 a) so as to maintain the temperature at a predetermined temperature. The periphery according to any one of claims 1 to 4, wherein the peripheral exposure light source (4) directly irradiates the light emitted from the light emitting diode (4a) to a predetermined peripheral position of the exposure object. Exposure device. In response to an instruction to expose a predetermined peripheral position of the exposure object (1), the light emitting diode (4a) is energized, and it is instructed not to expose the peripheral predetermined position of the exposure object (1). 6. The peripheral exposure apparatus according to claim 1, further comprising an energization control device that prevents energization of the light emitting diode (4a) in response thereto.

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