JPWO2015015749A1 - Exposure equipment - Google Patents

Abstract

The light source 10 according to an aspect of the present invention includes a light emitting element 11 and a homogenizer 13 provided corresponding to the light emitting element 11. The light emitted from the light emitting element 11 is converted into converted light having a uniform intensity distribution by the homogenizer 13 and output from the light source 10.

Description

  The present invention relates to a light source for an exposure apparatus that projects a pattern formed on a reticle (also called a photomask) using a photolithography technique onto a substrate, and an exposure apparatus that uses the light source.

  Examples of such an exposure apparatus include an exposure apparatus that projects a pattern of a MEMS (Micro Electronic Mechanical System) structure on a substrate, and an exposure apparatus that projects a semiconductor circuit pattern on the substrate. As light sources for these exposure apparatuses, light sources using mercury lamps as light emitters are widely used.

  FIG. 8 shows a schematic configuration diagram of an optical system of a conventional exposure apparatus 900 using a mercury lamp as a light emitter. The exposure apparatus 900 includes an exposure apparatus light source 910, a reticle support 960 that supports the reticle R, an illumination optical system 920 that guides light output from the exposure apparatus light source 910 to the reticle R, and a wafer that is an exposure object. An exposure object support 970 that supports the substrate W, a projection optical system 950 that projects the light transmitted through the reticle R onto the substrate W, and a shutter 940 that turns on and off the light output from the light source 910 for the exposure apparatus. A light amount detection unit 930 that detects the amount of light irradiated onto the reticle R when the shutter 940 is in an on state, and an exposure control unit that controls the operation of the light source for the exposure apparatus based on preset exposure conditions ( (Not shown).

  The light source 910 for an exposure apparatus includes a mercury lamp 911 that generates g-line with a wavelength of 436 nm, h-line with 405 nm, or i-line with 365 nm, an elliptical mirror 912 that collects light generated by the mercury lamp 911, and mercury. A light emission control unit (not shown) that controls the light emission of the lamp 911 is configured.

  The illumination optical system 920 has passed through a dichroic mirror 921 for removing light in an unnecessary wavelength band spreading around the bright line, a bandpass filter 922 for narrowing the light reflected by the dichroic mirror 921, and a bandpass filter 922. An input lens 923 that causes light to enter the fly-eye lens 924, a fly-eye lens 924 and a condenser lens 927 for uniformizing the intensity distribution of illumination light applied to the reticle R, and a collector lens that collects light emitted from the fly-eye lens 924 925, a mirror 926, and the like.

  The shutter 940 includes a shutter blade 941 in which large-diameter portions (blade portions) that block the beam and small-diameter portions (boss portions) that allow the beam to pass, and a stepping motor 942 that rotationally drives the shutter blade 941. It is configured. The shutter 940 is switched between an off state in which light output from the exposure apparatus light source 910 is blocked and an on state in which the reticle R is irradiated by controlling the rotational angle position of the shutter blade 941 by the stepping motor 942. That is, when the shutter blade 941 is set to a rotation angle position where the large diameter portion is positioned on the optical path, the light output from the light source 910 for the exposure apparatus is blocked by the large diameter portion and is turned off. Is set to the rotation angle position where the small diameter portion is positioned on the optical path, the light output from the light source 910 for the exposure apparatus passes through the small diameter portion and is turned on. The operation of the shutter 940 is controlled by the exposure control unit.

  The light amount detection unit 930 reflects a part of the light output toward the reticle (for example, about 1 to 3%) when the shutter 940 is on, and the light reflected by the partial reflection mirror 932. From an integrator (integrated illuminance detector) 933 that detects the integrated illuminance of illumination light irradiated on the reticle R by detecting the integrated illuminance of light collected by the collector lens 931. Composed. The projection optical system 950 includes a projection lens 951 that reduces the light transmitted through the reticle R at a predetermined magnification and projects a pattern drawn on the reticle R onto the substrate W.

  In a conventional exposure apparatus using such a mercury lamp 911 as a light emitter, there is a problem that the life of the mercury lamp is as short as several months, or a problem caused by heat generated by the mercury lamp (for example, heat resistance). There is a problem that it is necessary to use an expensive elliptical mirror with high performance, and a large-scale cooling device including a large cooling fan and a waste heat duct. As means for solving such a problem, a light source for an exposure apparatus using a plurality of light emitting diodes (LEDs) instead of the mercury lamp 911 has been proposed (for example, see Patent Document 1 and Patent Document 2).

JP 2005-303033 A JP 2007-292999 A

  However, the light source for an exposure apparatus as described in the above-mentioned patent document is a collection of light emitted from individual LEDs at a predetermined convergence point. Therefore, in order to make the intensity distribution of the illumination light irradiated to the reticle uniform, it is necessary to use a fly-eye lens, an input lens, or the like that is the same as before (or has a higher diffusibility).

  The present invention has been made in view of such circumstances, and an object thereof is to provide a light source for an exposure apparatus that can further simplify the configuration of the exposure apparatus. It is another object of the present invention to provide an exposure apparatus having a simple configuration. Furthermore, it aims at illumination numerical aperture control (image resolution / contrast).

  In order to solve the above problems and achieve the object, a first aspect illustrating the present invention is a light source. The light source includes a light emitting element and a homogenizer provided corresponding to the light emitting element, and the light emitted from the light emitting element is converted into converted light having a uniform intensity distribution by the homogenizer and output. Configured as follows.

  In addition, this light source can be equipped with the light emitting element array part which has two or more said light emitting elements. In addition, the light emitting element array unit may be configured such that a plurality of the light emitting elements are integrally formed on a substrate.

  In addition, the light source can include a homogenizer array unit having a plurality of the homogenizers provided corresponding to the plurality of light emitting elements. Moreover, the said homogenizer array part can be comprised so that the said several homogenizer may be formed integrally.

  The light source includes: a light emitting element array unit having a plurality of the light emitting elements; and a homogenizer array unit having a plurality of the homogenizers provided corresponding to the plurality of light emitting elements. And the said homogenizer array part can be comprised so that the said several light emitting element and the said several homogenizer may be integrally formed on a board | substrate.

  The homogenizer can be a transmissive beam homogenizer or a diffractive beam homogenizer.

  A light source monitor configured to individually detect the intensity of light emitted from the plurality of light emitting elements; and a light emission control unit configured to individually control light emission of the plurality of light emitting elements, A light emission control part can be comprised so that the light emission state of the said light emitting element may be controlled based on the intensity | strength of the light detected by the said light source monitor.

  In this case, the light source monitor can be configured to be able to individually detect the intensities of the plurality of converted lights output from the homogenizer array unit. The light emission control unit can be configured to control the light emission intensity of each light emitting element based on the intensity of the converted light detected by the light source monitor, or can be detected by the light source monitor. The light emission time of each light emitting element can be controlled based on the intensity of the converted light.

  In addition, the said light source can be comprised so that it may be used as a light source for exposure apparatuses.

  A second aspect illustrating the present invention is an exposure apparatus. The exposure apparatus includes the above-described light source, a reticle support that supports a reticle on which a predetermined pattern is formed, and a condenser lens that converges light output from the light source onto the reticle supported by the reticle support. An exposure object support unit that supports the exposure object; a projection lens that irradiates the exposure object supported by the exposure object support unit with light transmitted through the reticle; and a preset exposure condition. And an exposure control unit for controlling the operation of the light source.

  It is also possible to provide an integrator for detecting the integrated illuminance of the light applied to the reticle, and the exposure control unit is configured to control light emission of the light source based on the integrated illuminance detected by the integrator. good.

  The light source of the first aspect includes a light emitting element and a homogenizer provided corresponding to the light emitting element, and the light emitted from the light emitting element is converted into converted light having a uniform intensity distribution by the homogenizer and output. . That is, the light output from the light source is not output from the light emitting element (referred to as unit output light) with the intensity distribution but is converted into converted light having a uniform intensity distribution and output. . Therefore, on the exposure apparatus side, the light output from the light source has only to be converged on the reticle by the condenser lens, and the fly-eye lens, input lens, etc. that are required because the unit output light has a non-uniform intensity distribution Can be deleted. Further, by arranging a plurality of light emitting elements and homogenizers in an array, the influence of individual errors can be reduced by the averaging effect. Therefore, according to the light source of this aspect, the exposure apparatus can be reduced in size and simplified.

  Further, since the exposure apparatus of the second aspect is configured using the light source of the first aspect, it is possible to provide an exposure apparatus having a small and simple configuration.

It is a schematic block diagram of the optical system of the exposure apparatus to which this invention is applied. It is an arrow view of II-arrow view in FIG. It is the simulation data which simulated a mode that the light of the Gaussian distribution radiate | emitted from the light emitting element was converted into the conversion light of uniform intensity distribution by a homogenizer. It is a graph which shows intensity distribution of the light radiate | emitted from a light emitting element. It is a graph which shows intensity distribution of the converted light by which intensity distribution was converted by the homogenizer. FIG. 6 is an optical path diagram illustrating a state from when the light emitted from the light emitting element array unit passes through the homogenizer array unit and the condenser lens and is irradiated to the reticle. (A) Intensity distribution of light incident on the homogenizer array section, (b) Intensity distribution of light incident on the condenser lens, (c) Intensity distribution of light incident on the reticle R with respect to 3 rows × 3 columns It is explanatory drawing shown in. It is a schematic block diagram of the optical system of the conventional exposure apparatus.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. FIG. 1 shows a schematic configuration diagram of an optical system of an exposure apparatus ES to which the present invention is applied. The exposure apparatus ES detects an exposure apparatus light source 10, an illumination optical system 20 that guides the light output from the exposure apparatus light source 10 to the reticle R, and the light output from the exposure apparatus light source 10 and applied to the reticle R. A light detection unit 30, a projection optical system 50 that projects light transmitted through the reticle R onto the substrate W, a reticle support unit 60 that supports the reticle R, and an exposure that supports a substrate W such as a wafer that is an exposure object. The object support unit 70 and an exposure control unit 80 that controls the operation of the entire exposure apparatus based on preset exposure conditions are provided.

  The light source 10 for exposure apparatus includes a light emitting element array section 12 provided with a plurality of light emitting elements 11, 11, 11,..., And a plurality of homogenizers 13, 13, 13. Are provided, a cooling structure 18 for cooling the light emitting elements 11, a light emission control section 81 configured to individually control light emission of the light emitting elements 11, 11, 11.

  The light emitting element 11 is preferably a device such as an LED (light emitting diode) that generates ultraviolet light having a wavelength of 405 nm, which is the same as the h-line of a mercury lamp, or a semiconductor laser (LD) that generates ultraviolet laser light having the same wavelength. Can be used. The light emitting element array unit 12 can be configured by integrally forming a plurality of light emitting elements 11, 11, 11... On a substrate. Such a light emitting element array unit 12 has, as shown in FIG. 2 as viewed in the direction of arrows II to II in FIG. 1, for example, the light emitting elements 11 are arranged on a substrate 15 such as a ceramic substrate in m rows × n columns ( m and n are both integers of 2 or more, and m = n = 10 in the illustrated configuration example. The arrangement pattern of the light emitting elements 11 can be set as appropriate, such as a concentric circle shape, a staggered lattice shape, or a hexagonal crystal shape.

  The homogenizer 13 is an optical element that converts the light (unit output light) emitted from the light emitting element 11 into converted light having a uniform intensity distribution and outputs the converted light. As is well known, light output from light emitting elements such as LEDs and semiconductor lasers has a Gaussian distribution of light intensity in the plane perpendicular to the optical axis (beam cross-sectional intensity). The homogenizer 13 converts unit output light having non-uniform cross-sectional intensity into converted light having a top hat-shaped intensity distribution with uniform cross-sectional intensity and outputs the converted light.

  FIG. 3 shows data simulating a state in which unit output light having a Gaussian distribution emitted from the light emitting element 11 is converted into converted light having a top hat intensity distribution by the homogenizer 13. 4 shows the intensity distribution (Gaussian distribution) of the unit output light emitted from the light emitting element 11, and FIG. 5 shows the intensity distribution of the converted light converted into a top hat shape by the homogenizer 13. As shown in FIG. The homogenizer 13 illustrated in FIG. 3 is a transmissive beam homogenizer using an aspheric lens, and shows a state in which a high density light beam at the center of the beam and a low density light beam at the outer periphery of the beam are equalized. 4 and 5, the horizontal axis represents the distance in the radial direction of the beam, and the vertical axis represents the light intensity normalized with the maximum value being 1.

  The homogenizer array unit 14 includes homogenizers 13, 13, 13... Corresponding to the light emitting elements 11, 11, 11... Of the light emitting element array unit 12, and is converted into a uniform intensity distribution by each homogenizer 13. A plurality of converted lights are output from the homogenizer array unit 14. The homogenizer array unit 14 can be formed by integrally forming a plurality of homogenizers 13, 13, 13. Such a homogenizer array unit 14 uses, for example, a resin material having a required transmission characteristic, and forms a homogenizer 13 in an m-row × n-column matrix using known means such as casting or injection molding. Can be produced. A glass material may be used and produced by a molding means such as hot press. The arrangement pattern of the homogenizer 13 can also be concentric, staggered, hexagonal, or the like in accordance with the arrangement pattern of the light emitting elements 11.

  The light emitting element array section 12 and the homogenizer array section 14 may be configured by integrally forming a plurality of light emitting elements 11, 11, 11,... And corresponding homogenizers 13, 13, 13. good. For example, a homogenizer 13 corresponding to each light emitting element (LED circuit or the like) 11 is integrally formed on the substrate 15 such as an on-chip lens or an LED mold substrate in a solid-state imaging device such as a CCD or CMOS. You may do it.

  The cooling structure 18 is a structure for removing heat generated by light emission of the light emitting element 11 and cooling the light emitting element 11, and is provided on the back side (non-light emitting side) of the substrate 15 of the light emitting element array unit. . FIG. 1 illustrates an air-cooling type cooling structure including a heat sink 18a to which the substrate 15 of the light emitting element array section is attached and a fan 18b that blows air to the heat sink 18a to cool it. The cooling structure 18 may have an appropriate form such as a liquid-cooled form using a liquid such as an inert liquid or a coolant, a form using a heat pipe as a medium, or a form using these in combination. it can.

  The illumination optical system 20 includes a collector lens 25 that collects light (m × n converted lights) output from the exposure apparatus light source 10 and a part of the light output from the exposure apparatus light source 10 (for example, 1 to 3%). ) Is transmitted to the light detection unit 30 side, and the other is reflected to the condenser lens 27 side. The condenser 26 is configured to converge the light reflected by the mirror 26 onto the reticle R. In this embodiment, a configuration in which a high-reflectance mirror is used as the mirror 26 and the main optical path is bent by 90 degrees is exemplified. However, a partial reflection mirror having a reflectivity of about 1 to 3% is used as the mirror 26. May be configured linearly.

  The light detection unit 30 includes a collector lens 31 that collects light transmitted through the mirror 26 (referred to as monitor light), a beam splitter 32 that divides the monitor light at a predetermined ratio, and an integrator (integrated illuminance detector) that detects the integrated illuminance of the monitor light. 33, and a light source monitor 35 for detecting the intensity distribution of the monitor light.

  The integrator 33 detects the integrated illuminance of the illumination light applied to the reticle R by detecting the integrated illuminance of the monitor light that is an aggregate of m × n converted lights. The integrator 33 is arranged at a conjugate (object image relationship) position with the reticle R (illumination region). The integrator 33 can be configured using, for example, a photodiode having detection sensitivity with respect to light in the wavelength band of monitor light. The integrated illuminance of the illumination light detected by the integrator 33 is output to the light emission control unit 81.

  The light source monitor 35 is configured to be able to individually detect the intensity of m × n converted lights, and can detect the intensity distribution of m × n converted lights by detecting the intensity distribution of the monitor light. Yes. The light source monitor 35 is disposed at a conjugate (object image relationship) position with the light emitting element array unit 12. The light source monitor 35 has a detection sensitivity with respect to light in the wavelength band of the monitor light, and is configured using a solid-state imaging device such as a CCD or CMOS having a pixel pitch and a number of pixels that can sufficiently resolve each converted light. can do. The intensity distribution of the monitor light detected by the light source monitor 35 is also output to the light emission control unit 81.

  The projection optical system 50 includes a projection lens 51 that irradiates the exposure target W with light transmitted through the reticle R. The image of the circuit pattern drawn on the reticle R is projected onto the exposure target W by the projection lens 51 at a predetermined reduction magnification, and a circuit pattern is formed on the exposure target W.

  The reticle support unit 60 has a reticle stage (not shown) for moving the reticle R in the X-Y direction in the horizontal plane, and the exposure target support unit 70 has the exposure target W in the X-Y-Z direction in the horizontal plane. An exposure table (not shown) to be moved is provided.

  The exposure control unit 80 operates each part of the exposure apparatus ES such as the light source 10 for the exposure apparatus, the reticle stage of the reticle support unit 60, and the exposure table of the exposure object support unit 70 based on preset exposure conditions. Overall control. Specifically, the exposure control unit 80 controls the operation of the exposure apparatus light source 10 via the light emission control unit 81 that directly controls the operation of the exposure apparatus light source 10. These control units are configured by a control computer and a control board of each unit. Hereinafter, the operation of the exposure apparatus light source 10 and the control mode of the exposure apparatus light source 10 mainly including the light emission control unit 81 will be described.

  FIG. 6 shows an optical path diagram until light emitted from the light emitting element array unit 12 passes through the homogenizer array unit 14 and the condenser lens 27 and is irradiated onto the reticle R. The light emitting element array unit 12 and the reticle R (illumination region) are disposed at the object side / image side focal position of the condenser lens 27. Further, the intensity distribution of light at each of the positions VIIa, VIIb, and VIIc indicated in the drawing, that is, (a) the intensity distribution of the light incident on the homogenizer array section 14, and (b) the intensity of the light incident on the condenser lens 27. FIGS. 7A, 7B, and 7C schematically show the distribution and (c) the intensity distribution of light incident on the reticle R for 3 rows × 3 columns.

  The unit output light emitted from each light emitting element 11 of the light emitting element array unit 12 has a Gaussian distribution of the cross-sectional intensity of the beam. Therefore, the light incident on the homogenizer array section 14 becomes an aggregate of m × n unit output lights of Gaussian distribution emitted from each light emitting element 11 as shown in FIG. Each unit output light is incident on the corresponding homogenizer 13 and converted into converted light having a top hat-shaped intensity distribution with uniform cross-sectional intensity (see FIGS. 3 to 5 and the related description described above). Therefore, the light output from the light source 10 for exposure apparatus and incident on the condenser lens 27 is a set of m × n converted lights whose intensity distribution is uniformed by the homogenizers 13 as shown in FIG. 7B. Become a body. The same applies to the monitor light incident on the light detection unit 30.

  The m × n converted lights incident on the condenser lens 27 are converged on the reticle R by this lens. That is, m × n converted lights each having a uniform intensity distribution are integrally combined on the reticle. Therefore, as shown in FIG. 7C, the light incident on the reticle R, that is, the illumination light is light obtained by superimposing m × n top hat-shaped converted lights. Therefore, if the intensity of individual converted light is different for m × n converted lights, for example, if the light emission intensity varies for the light emitting elements 11, 11, 11. Even when some of the light emitting elements are damaged and do not light up, the intensity distribution of the illumination light on which these are superimposed is kept uniform. Further, the illumination numerical aperture as well as the brightness can be changed and controlled by changing the number of actual light emitting elements in the light emitting element array section 12, and the resolution and contrast of the image are the same. The process in which the light transmitted through the reticle R is projected onto the exposure object W by the projection lens 51 is the same as that of a conventional exposure apparatus using a mercury lamp or the like as a light emitter.

  In the exposure apparatus ES, the exposure control unit 80 controls the light emission of the exposure apparatus light source 10 based on the integrated illuminance detected by the integrator 33 of the light detection unit 30. The light incident on the integrator 33 is light collected by the collector lens 31 with the intensity distribution made uniform by the homogenizers 13 of the homogenizer array section 14 in the same manner as the light incident on the reticle R. That is, the integrator 33 detects the integrated illuminance (illuminance per unit time × irradiation time) over the entire monitor light, and detects the integrated illuminance of the illumination light applied to the reticle R. Therefore, the integrator 33 can use a single light receiving element such as a photodiode. The uniform illuminance can also be detected and controlled by using a light receiving sensor composed of a plurality of pixels as the integrator 33.

  The exposure control unit 80 outputs a command signal to start light emission to the light emission control unit 81 to cause the light emitting elements 11, 11, 11... Of the light emitting element array unit 12 to emit light. When the exposure amount set as is reached, a light emission stop command signal is output to stop the light emission of the light emitting elements 11, 11, 11. The exposure control unit 80 outputs a light emission start command signal and an exposure amount command signal to the light emission control unit 81, and when the integrated illuminance detected by the integrator 33 reaches the commanded exposure amount, the light emission control unit 81 may stop the light emission of the light emitting elements 11, 11, 11,.

  That is, in the exposure apparatus ES, by controlling the light emission of the light source 10 for the exposure apparatus, specifically, by turning on / off the light emitting elements 11, 11, 11. The illumination light is turned on / off. With such a configuration, the shutter (see FIG. 8) provided in the conventional exposure apparatus can be deleted. Further, since converted light having a uniform intensity distribution is output from the light source 10 for the exposure apparatus, the fly-eye lens provided in the conventional exposure apparatus can be eliminated. Therefore, according to the exposure apparatus ES having such a configuration, the apparatus configuration can be greatly simplified and downsized.

  Furthermore, in a conventional exposure apparatus that uses a mercury lamp as a light emitter, the lifetime of the mercury lamp is as short as several months, and the mercury lamp is set to be always lit regardless of whether the exposure apparatus is in operation or not. Therefore, there is a problem that the invalid power consumption is great, but according to this configuration, the lifetime of the light emitting element is as long as several years or more, and the light emitting element is lit only at the time of exposure. This problem can be solved and the running cost can be greatly reduced.

  Next, a control mode of the light source 10 for the exposure apparatus by the light emission control unit 81 will be described. In the exposure apparatus ES, the light emission control unit 81 controls the light emission state of each light emitting element 11 of the light emitting element array unit 12 based on the intensity distribution of the monitor light detected by the light source monitor 35. As described above, the light source monitor 35 is disposed at a conjugate position with the light emitting element array unit 12, and an image of each light emitting element 11 constituting the light emitting element array unit 12 is formed on the light source monitor 35.

  The light emission control unit 81 detects the relative intensity of the m × n converted lights detected by the light source monitor 35, that is, the relative intensity of each light emitting element 11 constituting the light emitting element array unit 12 (and the integrated illuminance detected by the integrator 33). ), The light emitting state of each light emitting element 11 of the light emitting element array unit 12 is controlled. For example, when all the 10 rows × 10 columns of the light emitting elements 11 constituting the light emitting element array unit 12 are lit with the driving power having a light emission intensity of 1 (standard value), the light emitting elements 11 of 2 rows and 5 columns Only the intensity of the emitted converted light (more precisely, the converted light emitted from the light-emitting elements 11 in 2 rows and 5 columns, converted by the corresponding homogenizer 13, and the same hereinafter) is 0.8 or 1.2, etc. Assume the case.

  At this time, the light emission control unit 81 has the same integrated illuminance of converted light emitted from the light emitting elements 11 in 2 rows and 5 columns as the integrated illuminance of converted light emitted from other light emitting elements 11 (for example, ± 5%). The light emitting state of the light emitting element (or another light emitting element) 11 is controlled so as to be within a predetermined allowable width of about a certain degree. Examples of the means for controlling the light emission state include a control form for adjusting the light emission intensity of the light emitting element 11 and a control form for adjusting the light emission time of the light emitting element 11.

  In the control mode in which the light emission intensity of the light emitting element 11 is adjusted, the intensity of the converted light emitted from the light emitting elements in 2 rows and 5 columns is the same as the intensity of the converted light emitted from the other light emitting elements. The driving current of the light emitting elements (or other light emitting elements) in the column is controlled. In the control mode in which the light emission time of the light emitting element 11 is adjusted, the integrated illuminance of the converted light emitted from the 2 × 5 light emitting elements is the same as the integrated illuminance of the converted light emitted from the other light emitting elements. The light emission time of the light emitting elements in row 5 column (or other light emitting elements) is controlled.

  According to the light source 10 for an exposure apparatus provided with such a light emission control unit 81, in addition to the effect of averaging by overlapping the plurality of converted lights, the integrated illuminance between the plurality of converted lights forming the illumination light can be increased. It can be made uniform, and the homogeneity of the illumination light can be further increased. In particular, the light emitting elements 11, 11, 11... Of the light emitting element array unit 12 are caused to emit light in an arbitrary shape such as a circle or a polygon, a ring shape or a frame having an arbitrary outer shape, a line shape, a cross shape, or the like. In addition, the contrast and resolution of the image projected on the exposure object W can be improved.

  In the exposure apparatus light source 10, the light source monitor 35 is configured to detect the relative light emission intensity of each light emitting element 11 of the light emitting element array unit 12, and the detected light emission intensity has a uniform intensity distribution. The degree of contribution of each light emitting element to the illuminance of the converted illumination light is expressed. For this reason, the illuminance control can be performed more accurately by controlling the corresponding light emitting element according to the intensity of the converted light detected by the light emission monitor 35. The conjugate relationship may be changed by inserting a lens in the optical path of the light source monitor 35 so that m × n pieces of converted light having uniform intensity distributions are incident on the light source monitor 35. According to such a configuration, the peak intensity of the light emitted from each light emitting element 11 is compressed and equalized, so that the dynamic range of the light source monitor 35 can be substantially expanded.

  The light emission control unit 81 outputs an alarm such as a warning or an alarm based on the intensity distribution of the m × n converted lights detected by the light source monitor 35. For example, in the above configuration example, even when the drive current of the light emitting element in 2 rows and 5 columns is adjusted within a predetermined range, the light emission intensity does not become the same as that of other light emitting elements, or the light emission in 2 rows and 5 columns Even if the light emission time of the element is adjusted within a predetermined range set in advance, a warning indicating that there is an abnormality in the light emitting element in 2 rows and 5 columns is output when the integrated illuminance does not become the same as other light emitting elements. Further, for example, from the intensity distribution of m × n converted lights detected by the light source monitor 35, the light emitting elements 11, 11, 11... Of the light emitting element array unit 12 are set at a predetermined ratio (for example, about 15%). ) When it is determined that no light is emitted or the light emission intensity is low, an alarm indicating that there is an abnormality in the light emitting element array unit 12 is output.

  These warnings, alarms, and the like are output from the light emission control unit 81 to the exposure control unit 80, and the exposure control unit 80 displays the alarm contents on the operation panel 85 of the exposure apparatus ES and externally via the I / O port 86. In addition to outputting an alarm signal, an interlock that temporarily stops the operation of the exposure apparatus ES is executed as necessary. The operator of the exposure apparatus ES can take action according to the content of the alarm. For example, the light emitting element array unit 12 or the exposure apparatus light source 10 is prepared at the stage when the warning occurs, and an appropriate one before the alarm is generated. Maintenance and replacement work, etc. can be carried out accurately at the right time.

  As described above, in the exposure apparatus ES, the light source 10 for the exposure apparatus includes a light emitting element array section 12 provided with a plurality of light emitting elements 11, 11, 11,... And each light emitting element 11 in the light emitting element array section. And a homogenizer array section 14 having a plurality of corresponding homogenizers 13, 13,..., And the light emitted from each light emitting element 11 is converted into converted light having a uniform intensity distribution by each homogenizer 13 and output. Therefore, the light source for the exposure apparatus itself can be reduced in size, and it is not necessary to provide beam shaping means such as a fly-eye lens on the exposure apparatus side, and the exposure apparatus can be reduced in size and simplified.

  In the embodiment, a transmissive beam homogenizer using an aspheric lens is exemplified as the homogenizer 13, but a diffractive beam homogenizer using a DOE lens may be used. A diffractive beam homogenizer can provide an achromatic effect, and when the light emitting element 11 has a relatively wide wavelength width, or a light emitting element having a different emission wavelength (for example, an h-line light-emitting element and an i-line light-emitting element). Even in the case of a light emitting element array in which elements, or light emitting elements of three colors of R, G, B, etc.) are provided on a substrate, the light in each wavelength region is efficiently converged on the reticle R. Can do.

  In addition, the light emitting elements 11, 11, 11... Of the light emitting element array unit 12 have been basically described in the case where the light emission wavelengths are the same. However, as described above, the light emitting elements having different light emission wavelengths are arranged in a predetermined arrangement. The light emission control unit 81 may be configured to control the light emission of the light emitting elements selectively or in combination based on the exposure conditions.

The present invention relates to a pattern formed on a reticle (also called a photomask) using photolithography exposure equipment to be projected on the substrate.

The present invention has been made in view of such circumstances, and aims to provide an exposure apparatus easy bright configuration.

In order to solve the above problems and achieve the object, an exposure apparatus exemplifying the present invention is provided with a light emitting element array section provided with a plurality of light emitting elements, and provided corresponding to each of the plurality of light emitting elements. A homogenizer array unit having a plurality of homogenizers that convert and output light emitted from each of the light emitting elements into converted light having a uniform intensity distribution, and individually detect the intensity of the light emitted from the plurality of light emitting elements An exposure apparatus light source having a configured light source monitor, and a light emission control unit configured to individually control light emission of the plurality of light emitting elements, and a reticle support unit that supports a reticle on which a predetermined pattern is formed A condenser lens for converging a plurality of lights output from the light source for the exposure apparatus to the reticle supported by the reticle support, and an exposure object support for supporting the exposure object A projection lens that irradiates the exposure object supported by the exposure object support unit with light transmitted through the reticle, and an integrator that detects an integrated illuminance of the light irradiated on the reticle. An exposure control unit that controls the operation of the light source for the exposure apparatus based on the exposure conditions and controls the light emission of the light source for the exposure apparatus based on the integrated illuminance detected by the integrator.

Also, the light-emitting element array unit, a plurality of the light emitting element is configured to be integrally formed on the substrate.

The front Symbol homogenizer array unit, a plurality of the homogenizer can be configured to be integrally formed.

The front Symbol emitting element array portion and the homogenizer array unit, a plurality of light emitting elements and a plurality of the homogenizer is configured to be integrally formed on the substrate.

In this case, the light source monitor can be detectably configure intensities of a plurality of the converted light output from the homogenizer. The light emission control unit can be configured to control the light emission intensity of the light emitting element based on the intensity of the converted light detected by the light source monitor, or the light emission monitor detected by the light source monitor The light emission time of the light emitting element can be controlled based on the intensity of the converted light.

According to the present invention, an exposure apparatus having a small and simple structure can be provided.

In order to solve the above problems and achieve the object, an exposure apparatus exemplifying the present invention is provided with a light emitting element array section provided with a plurality of light emitting elements, and provided corresponding to each of the plurality of light emitting elements. a homogenizer array portion having a plurality of homogenizer that converts the converted light having a uniform intensity distribution of light emitted from each light emitting element, which is capable of controlling the light emission of the previous SL plurality of light emitting elements individually A light source for the exposure apparatus having a light emission control section; a reticle support section for supporting a reticle on which a predetermined pattern is formed; and a plurality of lights output from the light source for the exposure apparatus are supported by the reticle support section. a condenser lens for converging the reticle, a source monitor that is detectably individually configured the intensity of light emitted from the plurality of light emitting elements, integration of light irradiated on the reticle A light detection unit including an integrator for detecting the degree of light; and a part of light emitted from the light source for the exposure apparatus is transmitted toward the light detection unit, and the remaining light is reflected toward the condenser lens. A mirror to be exposed , an exposure object support part that supports the exposure object, a projection lens that irradiates the exposure object supported by the exposure object support part with light transmitted through the reticle, and an operation of the entire apparatus. An exposure control unit that controls the light emission control unit detected by the integrator of the light detection unit and the light intensity of the plurality of light emitting elements detected by the light source monitor of the light detection unit Using the integrated illuminance, light emission emitted from each light emitting element of the plurality of light emitting elements so that the integrated illuminance is the same when each of the plurality of light emitting elements of the light emitting element array unit emits light. The light emission control unit controls the light intensity of light emitted from each light emitting element of the plurality of light emitting elements, and the plurality of light emission A warning is output when any of the intensities of light emitted from each light emitting element of the element is not the same, and when a predetermined proportion of the light emitting elements among the plurality of light emitting elements are not emitting light, or the emission intensity is If it is low, an alarm is output, and the exposure control unit executes control based on the warning or alarm output by the light emission control unit.

Claims (15)

A light emitting element;
A homogenizer provided corresponding to the light emitting element,
A light source characterized in that light emitted from the light emitting element is converted into converted light having a uniform intensity distribution by the homogenizer and output. The light source according to claim 1,
A light source comprising a light emitting element array section having a plurality of the light emitting elements. The light source according to claim 2,
The light emitting element array unit includes a plurality of the light emitting elements integrally formed on a substrate. The light source according to claim 2 or claim 3,
A light source comprising a homogenizer array section having a plurality of the homogenizers provided corresponding to the plurality of light emitting elements. The light source according to claim 4.
In the homogenizer array unit, a plurality of the homogenizers are integrally formed. The light source according to claim 1,
A light emitting element array section having a plurality of the light emitting elements;
A homogenizer array section having a plurality of the homogenizers provided corresponding to each of the plurality of light emitting elements, and
The light-emitting element array unit and the homogenizer array unit include a plurality of the light-emitting elements and the plurality of homogenizers integrally formed on a substrate. The light source according to any one of claims 1 to 6,
The homogenizer is a transmissive beam homogenizer. The light source according to any one of claims 1 to 6,
The light source, wherein the homogenizer is a diffractive beam homogenizer. The light source according to any one of claims 4 to 6,
A light source monitor configured to individually detect the intensity of light emitted from the plurality of light emitting elements;
A light emission control unit configured to individually control light emission of the plurality of light emitting elements,
A light source, wherein the light emission control unit is configured to control a light emission state of the light emitting element based on an intensity of light detected by the light source monitor. The light source according to claim 9,
The light source monitor is
A light source configured to be capable of individually detecting the intensity of the plurality of converted lights output from the homogenizer array section. The light source according to claim 10,
The light emission control unit controls the light emission intensity of each of the light emitting elements based on the intensity of the converted light detected by the light source monitor. The light source according to claim 10 or claim 11,
The light emission control unit controls a light emission time of each light emitting element based on the intensity of the converted light detected by the light source monitor. The light source according to any one of claims 1 to 12,
The light source is used as a light source for an exposure apparatus. The light source according to any one of claims 1 to 12,
A reticle support for supporting the reticle on which a predetermined pattern is formed;
A condenser lens that converges the light output from the light source onto the reticle supported by the reticle support;
An exposure object support part for supporting the exposure object;
A projection lens for irradiating the exposure object supported by the exposure object support with light transmitted through the reticle;
An exposure apparatus comprising: an exposure control unit that controls an operation of the light source based on a preset exposure condition. The exposure apparatus according to claim 14, wherein
Comprising an integrator for detecting the integrated illuminance of light irradiated on the reticle;
The exposure apparatus, wherein the exposure control unit controls light emission of the light source based on the integrated illuminance detected by the integrator.

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