JP2011164599A - Method for sorting micromirror device, device for sorting micromirror device, and maskless exposure apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for sorting a micromirror device to obtain a drawing pattern with good linearity and no recess in a width or thickness direction, in a maskless exposure apparatus. <P>SOLUTION: The device for sorting a micromirror device includes: an illumination system illuminating a micromirror 21 of a micromirror device 2 with illumination light, an optical system allowing the diffracted light generated in the micromirror 21 to enter an image sensor 79; and a processing system 9 processing an image of the diffracted light distribution captured by the image sensor 79 and determining whether the micromirror device 2 is a non-defective product or a defective product. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a micromirror device sorting method and a micromirror device sorting device mounted on a maskless exposure apparatus for transferring and printing a pattern on a display device panel, a semiconductor mask, and the like, and in particular, the micromirror device flatness of the micromirror device. It relates to sex detection.

  A panel such as a liquid crystal or an organic EL (Electro Luminescence) is manufactured by baking a circuit pattern drawn on a mask on a substrate. As a process, after depositing a thin film on a glass substrate, a photoresist is applied, a circuit pattern is exposed and developed. Next, the underlying thin film is etched through the photoresist pattern to form a thin film pattern. By repeating this process a plurality of times and laminating thin film patterns, a circuit pattern in which the brightness of each pixel can be controlled is created.

  For color display, the color filter is formed on a glass substrate different from the glass substrate of the circuit pattern. First, a light shielding band called a black matrix that partitions red, green, and blue regions is formed first. Next, a red color filter is made by applying, exposing and developing a photoresist containing a red pigment.

  The same process is repeated for green and blue. Finally, a common transparent electrode pattern is formed by thin film deposition, resist coating, exposure / development, and etching, whereby a red, green, and blue (RGB) color filter is manufactured. In a liquid crystal panel, a liquid crystal display panel is completed by sandwiching liquid crystal between a glass substrate on which a circuit pattern is formed and a color filter, adding a light source and a polarizing plate on the illumination side, and a polarizing plate in a direction orthogonal to the light source on the emission side. .

  As described above, in the manufacturing process, exposure for printing a pattern on a photoresist is frequently used. A mask is used for exposure, but when a new display device is developed, the delivery time of the mask becomes a bottleneck for short-term development. In addition, when a large-sized television panel is manufactured, resources can be effectively used if a small panel is allocated to an extra space to be discarded according to market conditions.

  These can be handled by a maskless exposure apparatus that does not use a mask. A maskless exposure apparatus is disclosed in, for example, US Pat. No. 6,493,867 (Patent Document 1).

  In a maskless exposure apparatus, a pattern is formed by a micromirror device (hereinafter referred to as MMD) instead of a mask. The angle of the reflected light is switched by controlling the individual inclination angles of the two-dimensionally arranged mirror groups with transistors.

  The MMD forms an image on a substrate through a projection lens, but forms a pattern in which pixels having a reflection angle that transmits through the projection lens are white and pixels having a reflection angle that cannot be transmitted through the projection lens are black. The inclination angle of each micromirror of the MMD is controlled in conjunction with the movement of the stage on which the substrate is mounted, whereby the pattern is transferred onto the substrate. By installing the MMD with an inclination of 1 / M radian with respect to the stage moving direction, the pattern transfer position can be controlled with a resolution of 1 / M of the pixel pitch.

  Regarding the simulation of the transfer pattern image of the mask, for example, Y.M. Yoshitake et al., “Multispot scanning exposure system for excimer laser stepper”, SPIE, 1463, (1991) 678 (Non-patent Document 1).

US Pat. No. 6,493,867

Y. Yoshitake et al, "Multispot scanning exposure system for excimer laser stepper", SPIE, 1463, (1991) 678.

  In the above maskless exposure apparatus, a pattern is formed by transferring a micromirror image corresponding to a pixel to a substrate. Here, first, the function of the MMD will be described with reference to FIGS. 11 and 12. 11 is a cross-sectional view showing the ON state of the MMD micromirror, and FIG. 12 is a cross-sectional view showing the OFF state of the MMD micromirror.

  As shown in FIG. 11, the micromirror 21 is fixed to the yoke 22, and the yoke 22 is tilted by twisting of the hinge 23 due to the electrostatic force of the electrode 24, and as a result, the micromirror 21 is tilted by the angle α. .

  When the illumination light 110 is incident at an angle 2α with respect to the normal direction of the MMD substrate surface 26, the reflected light 111 is reflected in the normal direction of the MMD substrate surface 26.

  On the other hand, when the electrode 25 is turned ON, as shown in FIG. 12, the micromirror 21 is tilted in the direction opposite to that in FIG. As a result, the reflected light 111 is reflected in the direction of 4α with respect to the normal direction of the substrate surface 26 of the MMD.

  That is, when the inclination angle α of the micromirror 21 when the electrode 25 is OFF is 12 degrees, when the electrode 25 is turned ON, the reflection is performed in a direction of 48 degrees with respect to the normal direction of the substrate surface 26 of the MMD. Is done. The reflected light in the OFF state is shielded by a shading band (not shown).

  The configuration of the maskless exposure apparatus will be described with reference to FIG. FIG. 13 is a block diagram showing the configuration of the maskless exposure apparatus.

  In FIG. 13, the illumination light 110 emitted from the light source 11 is applied to the MMD 2 by the folding mirror 12 at a predetermined angle. The light reflected by the MMD 2 is projected on the substrate 5 by the projection lens 3 via the projection lens pupil 31. The substrate 5 is mounted on the stage 6, and the projected image 4 is superimposed and exposed on the entire surface of the substrate 5 by moving the stage 6.

  With reference to FIG. 14, a method of overlapping exposure will be described. FIG. 14 is a diagram for explaining an overlay exposure method using each MMD micromirror.

  As shown in FIG. 14, the MMD 2 is installed at an angle θ with respect to the moving direction 50 of the stage 6. The micromirror images 401 to 406 of the MMD 2 are switched between ON / OFF states in conjunction with the movement of the stage 6. When the amount of movement of the stage 6 during the ON / OFF switching cycle is set as the plot pitch PP and PP is selected to be larger than the pitch P of the micromirror image, the micromirror image is slightly shifted in the pixel region 51 on the substrate. Overexposure is performed.

  Here, the light intensity distribution in the X direction of each micromirror image at the time of overlapping exposure will be described with reference to FIGS. 15 is a diagram showing a light intensity distribution in the X direction of each micromirror image at the time of overlay exposure, FIG. 16 is a diagram showing an added light intensity distribution of the light intensity distribution shown in FIG. 15, and FIG. 17 is a 3 pixel × 1 pixel pattern It is a figure which shows light intensity distribution.

  The light intensity distribution in the direction X orthogonal to the moving direction 50 of the stage 6 corresponding to the micromirror images 401 to 406 is a distribution indicated by 4001 to 4006 in FIG. 4011 is shown.

  Then, as shown in FIG. 17, when a drawing pattern of 3 pixels in the X direction and 1 pixel in the stage movement direction Y is used and the light intensity distributions 4011 to 4013 of the respective pixels are added, a light intensity distribution 4100 is obtained. The slopes of the light intensity distributions 4011 to 4013 of each pixel are flattened by adding adjacent light intensity distributions. As a result, the two-dimensional pattern 4110 obtained has a good linearity.

  The above is the description in the ideal state where the light intensity distribution of the micromirror image is rectangular. Here, the case where the light intensity distribution is Gaussian will be described with reference to FIGS. 18 is a diagram showing the Gaussian distribution light intensity distribution of each micromirror image at the time of overlay exposure, FIG. 19 is a diagram showing the added light intensity distribution of the light intensity distribution shown in FIG. 18, and FIG. 20 is a Gaussian distribution micromirror image. It is a figure which shows the light intensity distribution of 3 pixel x 1 pixel pattern produced | generated by (3).

  As shown in FIG. 18, the light intensity distributions 4021 to 4026 correspond to the micromirror images 401 to 406. The light intensity distribution obtained by adding the light intensity distributions shown in FIG. 18 is as indicated by 4031 in FIG. In FIG. 19, the width of the inclined portion is narrower than the light intensity distribution 4011 formed by adding the rectangular micromirror images 4001 to 4006.

  Then, as shown in FIG. 20, when a drawing pattern of 3 pixels in the X direction and 1 pixel in the Y direction is made and the light intensity distributions 4031 to 4033 of each pixel are added, the slopes of the light intensity distributions 4031 to 4033 Since the width is narrow, the light intensity at the pixel boundary portion of the light intensity distribution 4200 obtained by adding the pixels is weak.

  As a result, a dent 4211 in the width direction and a dent 4212 in the thickness direction are generated at the pixel boundary of the two-dimensional pattern 4210 on the XY plane. When the pattern is used as a gate of a transistor, the recess 4211 in the width direction causes a change in the characteristics of the transistor. Further, since the photoresist itself remains as a pattern in the color filter, the depression 4212 in the thickness direction may cause a change in the brightness of the pixel.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an MMD sorting method and an MMD sorting apparatus for obtaining a drawing pattern with good linearity having no depressions in the width direction and the thickness direction in a maskless exposure apparatus.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

  In other words, the outline of a representative one is that an illumination system that irradiates illumination light to an MMD micromirror, an optical system that causes diffracted light generated by the micromirror to enter the image sensor, and a diffracted light distribution image captured by the image sensor And a processing system for determining whether the MMD is non-defective or defective.

  The effects obtained by typical ones of the inventions disclosed in the present application will be briefly described as follows.

  That is, the effect obtained by a typical one is simple and can quickly select MMD with good flatness, and therefore, in a maskless exposure apparatus using MMD, a straight line having no depression in the width direction or the thickness direction. A transfer pattern with good characteristics can be obtained, and the quality and reliability of the maskless exposure apparatus can be improved.

  In addition, since it is possible to monitor the deterioration over time of the flatness of the MMD mounted in the maskless exposure apparatus, it becomes possible to prevent the deterioration of the linearity of the transfer pattern in advance. The yield can be maintained in the manufacture of the semiconductor mask.

It is a block diagram which shows the structure of the micromirror device (MMD) sorter | selector which concerns on Embodiment 1 of this invention. It is explanatory drawing for demonstrating the necessity to use MMD with the sufficient flatness of a micromirror. It is a figure which shows Zh which is the difference of the height of the micromirror center of the MMD sorting device concerning Embodiment 1 of the present invention, and the circumference. It is a figure which shows the exposure simulation result at the time of micro mirror concave surface which made Zh the parameter of the MMD sorting device which concerns on Embodiment 1 of this invention. It is an enlarged view of the wedge glass of the MMD sorting device concerning Embodiment 1 of the present invention, a right angle prism, and a micromirror part. It is a flowchart which shows the flow of the micromirror flatness determination processing of the MMD selection apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the area | region division | segmentation of the diffracted light distribution image of the MMD selection apparatus which concerns on Embodiment 1 of this invention. It is a figure which shows the relationship between Zh and the evaluation value S which are the height difference of the micromirror center of the MMD sorting device concerning Embodiment 1 of the present invention, and the circumference. It is a block diagram which shows the structure of the maskless exposure apparatus which concerns on Embodiment 2 of this invention. It is a figure which shows the rotary aperture of the illumination system of the maskless exposure apparatus which concerns on Embodiment 2 of this invention. It is sectional drawing which shows the ON state of the micro mirror of MMD. It is sectional drawing which shows the OFF state of the micro mirror of MMD. It is a block diagram which shows the structure of a maskless exposure apparatus. It is a figure explaining the overlap exposure method by each micromirror of MMD. It is a figure which shows the light intensity distribution of the X direction of each micromirror image at the time of superposition exposure. It is a figure which shows the addition light intensity distribution of the light intensity distribution shown in FIG. It is a figure which shows the light intensity distribution of a 3 pixel x 1 pixel pattern. It is a figure which shows the Gaussian distribution light intensity distribution of each micromirror image at the time of superposition exposure. It is a figure which shows the addition light intensity distribution of the light intensity distribution shown in FIG. It is a figure which shows the light intensity distribution of 3 pixel x 1 pixel pattern produced | generated with a Gaussian distribution-type micromirror image.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiment, and the repetitive description thereof will be omitted.

(Embodiment 1)
With reference to FIG. 1, the configuration of a micromirror device (hereinafter referred to as MMD) sorting apparatus according to Embodiment 1 of the present invention will be described. FIG. 1 is a configuration diagram showing the configuration of the MMD sorting apparatus according to Embodiment 1 of the present invention.

  In FIG. 1, the MMD sorting apparatus includes an MMD 2, a processing system 9, a light source 70 and an optical fiber 71 as an illumination system, a collimating lens 72 as an optical system, a wedge glass 73, a right-angle prism 74, lenses 75, 77, 78, and A diaphragm 76, an image sensor 79, and a display system 900 are included. The MMD 2 is composed of a micro mirror 21.

  In the present embodiment, the MMD 2 is irradiated with parallel light at a predetermined angle, the reflected diffracted light is collimated by a lens, the diffracted light distribution is reduced and imaged on an image sensor by a lens system, and image processing is performed by a processing system 9. The diffracted light distribution characteristics are quantified, and the flatness of the micromirror 21 is detected.

  First, the necessity of using the MMD 2 with good flatness of the micromirror 21 will be described with reference to FIG. FIG. 2 is an explanatory diagram for explaining the necessity of using the MMD 2 with good flatness of the micromirror 21, and shows the action of the micromirror 21 with poor flatness.

  As shown in FIG. 2, the micromirror 21 is curved in a concave shape due to thermal stress at the time of manufacturing the MMD 2 and thermal stress due to illumination light irradiation. For this reason, the micromirror 21 has an action of converting the parallel light 110 into the condensed light 112, and an image of the micromirror 21 on the substrate 5 has a Gaussian distribution like a light intensity distribution 4021.

  As described with reference to FIG. 20, this causes a depression at the pixel boundary in the pattern. For this reason, first, it is necessary to select and use the MMD 2 having the micromirror 21 with good flatness. The flatness can be measured with a laser confocal microscope. However, since the measurement takes time and effort, the characteristics of the diffracted light distribution are used in this embodiment.

  Next, the principle of detection of a micromirror with good flatness in the MMD sorting apparatus according to Embodiment 1 of the present invention will be described with reference to FIGS. FIG. 3 is a diagram showing Zh, which is the difference between the height of the micromirror center and the periphery of the MMD sorting apparatus according to Embodiment 1 of the present invention, and FIG. 4 is Zh of the MMD sorting apparatus according to Embodiment 1 of the present invention. It is a figure which shows the exposure simulation result at the time of micro-mirror concave surface using as a parameter.

  In the present embodiment, attention is paid to the characteristics of the diffracted light distribution when the micromirror 21 is concave. When the concave surface is formed, the phase divergence at the peripheral portion with respect to the flat surface increases, and accordingly, the higher-order diffracted light intensity increases. Here, as shown in FIG. 3, the difference in height between the center and the periphery when the concave surface of the micromirror is approximated by a paraboloid is defined as Zh.

  The exposure simulation result shown in FIG. 4 shows the case where the size of the micromirror is 13.7 μm square. As shown in FIG. 4, as Zh increases, higher-order diffracted light is generated on the pupil, and the micromirror image on the substrate is rounded due to the condensing function of the concave surface. By imaging the diffracted light distribution on the pupil and quantifying the brightness of the higher-order diffracted light position with an evaluation value, the degree of concave surface can be quantified. Based on this evaluation value, an MMD having a micromirror with good flatness is selected. It becomes possible.

  Next, the operation of the MMD sorting apparatus according to Embodiment 1 of the present invention will be described with reference to FIGS. 1 and 5 to 8. 5 to 8 are explanatory diagrams for explaining the operation of the MMD sorting apparatus according to the first embodiment of the present invention. FIG. 5 is an enlarged view of the wedge glass, the right-angle prism, and the micromirror unit of the MMD sorting apparatus. FIG. 6 is a flowchart showing the flow of the micromirror flatness determination process, FIG. 7 is a diagram showing the region division of the diffracted light distribution image, and FIG. 8 is a graph showing the difference between the height of Zh and the evaluation value S between the micromirror center and the periphery It is a figure which shows a relationship.

  First, as shown in FIG. 1, the illumination light generated by the light source 70 is emitted from the optical fiber 71, becomes parallel light by the collimating lens 72, and is deflected by the wedge glass 73 by an angle θ <b> 1. The relationship between the angle θ1 and the angle β of the wedge glass 73 is given by the following equation (Equation 1), where n1 is the refractive index of the wedge glass 73.

θ1 = (n1-1) β (Formula 1)
The illumination light 710 emitted from the wedge glass 73 is incident on the right-angle prism 74, is incident on the micromirror 21 of the MMD2, and the reflected light is totally reflected by the inclined surface of the right-angle prism 74.

  Here, the optical path of the central ray 711 of the illumination light 710 inside the right-angle prism 74 will be described with reference to FIG.

  Hereinafter, a case where the inclination angle α of the micromirror is 12 degrees will be described. Note that θ1 to θ5 vary with the value of α in accordance with the following (Expression 2) to (Expression 5). In order for the reflected light to vertically enter the right-angle prism, the incident angle θ5 needs to be 2α = 24 degrees. At this time, the relationship between θ5 and θ4 is given by the following equation (Equation 2) where the refractive index of the right-angle prism is n2.

sin θ4 = sin θ5 / n2 (Expression 2)
If n2 = 1.5, θ5 = 24 degrees, so θ4 is 15.73 degrees. On the other hand, since the relationship between θ4 and θ3 is the following equation (Equation 3), θ3 is 29.27 degrees.

θ3 = 45−θ4 (Formula 3)
The refraction at the hypotenuse of the right-angle prism 74 is given by the following equation (Equation 4).

sin θ2 = n2 · sin θ3 (Expression 4)
As a result, θ2 is found to be 47.17 degrees. Since the relationship between θ1 and θ2 is the following equation (Equation 5), θ1 is 2.17 degrees.

θ1 = 45−θ2 (Formula 5)
The angle β of the wedge glass 73 for realizing this is 1.09 degrees when n1 = 1.5 from the equation (Equation 1).

  Here, referring again to FIG. 1, the optical path of the diffracted light 712 generated by the micromirror 21 will be described. After the diffracted light 712 is collimated by the lens 75, a portion unnecessary for measurement is cut by the diaphragm 76 installed at the position of the focal length f1 of the lens 75.

  The position of the diaphragm 76 is the Fourier transform plane of the micromirror 73, and is the position where the diffracted light distribution is detected with the best separation. The diaphragm 76 is larger than the field of view of the image sensor 79.

  Therefore, the relay reduction optical system is composed of the lens 77 and the lens 78. The aperture 76 is reduced to a ratio of the focal length f2 of the lens 77 and the focal length f3 of the lens 78, which is f3 / f2 times, and is imaged on the image sensor 79.

  Here, the distance between the lens 77 and the lens 78 is the sum of focal lengths, f2 + f3. The diffracted light distribution image 80 picked up by the image pickup element 79 is subjected to image processing by the processing system 9 to determine the concave nature of the micromirror 21.

  Next, the method for determining the concave surface of the micromirror 21 by the processing system 9 will be described with reference to the flowchart shown in FIG.

  First, in step 901, the diffracted light distribution is imaged by the image sensor 79. Next, in step 902, each diffracted light region is divided.

  According to the simulation result shown in FIG. 4, when the flatness of the micromirror 21 is good, the diffracted light intensity is strong at the four near the center, but the diffracted light intensity at the periphery increases as the surface becomes concave. I know it.

  Therefore, as shown in FIG. 7, the region in the aperture contour image 760 of the diffracted light distribution image 80 is divided into center portions 801 to 804 and peripheral portions 811 to 822.

  Next, in step 903, the average luminance value of each region is calculated. Using this, an evaluation value S is calculated in step 904. The evaluation value S is the average luminance of the central portions 801 to 804 as I1 to I4, the average value of I1 to I4 as m1, the average luminance of the peripheral portion as I11 to I22, and the average value of I11 to I22 as m2. It is represented by the formula of Formula 6).

  S is a value obtained by dividing the ratio of the average value of I1 to I4 and the standard deviation by the ratio of the average value of I11 to I22 and the standard deviation. The higher the concentration of diffracted light on I1 to I4, that is, the flatness is. The better, the larger the value.

  The relationship between the evaluation value calculated by the equation (Equation 6) and Zh which is the difference in height between the center and the periphery of the micromirror 21 is as shown in FIG. From the relationship shown in FIG. 8, it can be seen that the evaluation value S monotonously decreases with respect to Zh, and Zh can be monitored by the evaluation value S.

  As shown in FIG. 8, when the allowable value of Zh is set to 75 nm, the threshold value of the corresponding evaluation value S is 3.42.

  In the example shown in FIG. 8, the region 830 is a non-defective range with good flatness. In step 905 of FIG. 6, when this threshold value is used and the evaluation value S is larger than the threshold value, “good” and a diffracted light distribution image are displayed on the display system 900 in step 907 and In this case, the “defective product” and the diffracted light distribution image are displayed on the display system 900 in step 906.

  With the above processing, in the present embodiment, it is possible to select an MMD with good flatness of the micromirror 21.

(Embodiment 2)
In this embodiment, the MMD sorting apparatus of the first embodiment is mounted on a maskless exposure apparatus.

  The configuration and operation of the maskless exposure apparatus according to the second embodiment of the present invention will be described with reference to FIGS. FIG. 9 is a block diagram showing the configuration of the maskless exposure apparatus according to Embodiment 2 of the present invention, and FIG. 10 is a diagram showing the rotary aperture of the illumination system of the maskless exposure apparatus according to Embodiment 2 of the present invention. is there.

  In this embodiment, the diffracted light distribution is monitored on a maskless exposure apparatus.

  In FIG. 9, the maskless exposure apparatus is similar to the MMD sorting apparatus shown in FIG. 1, MMD2, processing system 90, light source 70, optical fiber 71, collimating lens 72, wedge glass 73, right angle prism 74, lenses 75, 77. 78, aperture 76, imaging element 79, and display system 900. The lenses 75 and 77 and the aperture 76 constitute the projection lens 3 of the maskless exposure apparatus. Further, a stage 6 on which the substrate 5 is mounted, a control system 91, an aperture 100, and an aperture driving unit 103 are provided.

  In FIG. 10, the aperture 100 includes a diffracted light aperture 101 and an exposure aperture 102.

  First, from the state of use as a normal maskless exposure apparatus, the control system 91 drives the stage 6, retracts the substrate 5, and moves the lens 78 and the image sensor 79 so that they are on the optical axis 300 of the projection lens 3. .

  Further, the control system 91 rotates the aperture driving unit 103 to switch from the exposure aperture 102 to the diffracted light aperture 101 shown in FIG. The radius rA of the diffracted light aperture 101 is determined by the following equation (Equation 7). The radius rA only needs to be smaller than this value.

rA = f0 · λ / P (Expression 7)
Here, f0 is the focal length of the collimating lens 72, λ is the wavelength of the illumination light, and P is the pitch of the micromirror 21 in the tilt direction. By determining rA by this equation, the diffracted light distributions can be detected without overlapping each other.

  Illumination light 710 generated by the light source 70 is emitted from the optical fiber 71, converted into parallel light by the collimator lens 72 through the aperture 100, deflected by the wedge glass 73, incident on and transmitted through the right-angle prism 74, and MMD2 micromirror 21 is illuminated.

  A central light beam 711 indicates the optical path at the center of the illumination light 710. The diffracted light 712 generated by the micromirror 21 is imaged at the position of the surface 55 of the substrate 5 by the projection lens 3 including the lens 75, the lens 77, and the diaphragm 76, collimated by the lens 78, and then image pickup device. The image is captured at 79.

  The lens 78 is installed at a distance of the focal length f4 from the surface 55 of the substrate, and the imaging element 79 is installed at the rear of the lens 78 and at the position of the focal length f4. As a result, the lens 77 and the lens 78 form an image of the diaphragm 76 on the image sensor 79. The diffracted light distribution image 80 captured by the image sensor 79 is processed by the processing system 9 in the same manner as in the first embodiment, and the determination result and the diffracted light distribution image are displayed on the display system 900.

  The determination result is sent to the control system 91, and when it is determined as “defective product”, the control system generates an alarm by means of warning sound, screen display, e-mail transmission, etc., and the control system 91 not shown as a warning log. To the recording section.

  With the above configuration, it is possible to evaluate whether or not the micromirror 21 has become concave after mounting the maskless exposure apparatus. When the surface is concaved beyond the threshold, it is possible to prevent deterioration of the linearity of the transferred pattern exceeding the allowable value by taking measures such as replacement of the MMD 2 promptly.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  For example, in the first and second embodiments, the evaluation value is calculated using the equation (Equation 6) to determine “good” or “defective”, but an exposure simulation as shown in FIG. A plurality of images of the resultant diffracted light distribution may be prepared, and “good” or “defective” may be determined by comparing the images themselves.

  The present invention can be widely applied to a maskless exposure apparatus and a projection exposure apparatus that transfer and print a pattern on a display device panel, a semiconductor mask, and the like.

  DESCRIPTION OF SYMBOLS 2 ... Micromirror device (MMD), 3 ... Projection lens, 4 ... Projection image, 5 ... Substrate, 6 ... Stage, 9 ... Processing system, 21 ... Micromirror, 22 ... Yoke, 23 ... Hinge, 24, 25 ... Electrode 26 ... MMD substrate surface, 31 ... projection lens pupil, 55 ... substrate surface, 70 ... light source, 71 ... optical fiber, 72 ... collimating lens, 73 ... wedge glass, 74 ... right angle prism, 75, 77, 78 ... Lens 76. Diaphragm 79 Image sensor 80 Diffracted light distribution image 91 Control system 900 Display system

Claims (8)

A method of selecting a micromirror device that generates a transfer pattern for performing maskless exposure,
Illuminating illumination light on a micromirror of the micromirror device, and imaging a diffracted light distribution from the micromirror;
Comparing information of a plurality of diffracted light distributions based on an exposure simulation result with information of a diffracted light distribution from the micromirror;
A method of selecting a micromirror device, comprising: displaying information on a good or defective product of the micromirror device and an image of the diffracted light distribution based on the comparison result. A method of selecting a micromirror device that generates a transfer pattern for performing maskless exposure,
Illuminating illumination light on a micromirror of the micromirror device, and imaging a diffracted light distribution from the micromirror;
Calculating a luminance average value for each region of the diffracted light distribution;
Calculating an evaluation value of the micromirror from the luminance average value;
Comparing the evaluation value with a threshold value;
A method of selecting a micromirror device, comprising: displaying information on a good or defective product of the micromirror device and an image of the diffracted light distribution based on the comparison result. A micromirror device sorting apparatus for sorting micromirror devices that generate a transfer pattern for performing maskless exposure,
An illumination system for irradiating illumination light to the micromirror of the micromirror device;
An optical system for causing the diffracted light generated by the micromirror to enter the imaging device;
A micromirror device sorting apparatus comprising: a processing system that processes a diffracted light distribution image picked up by the image pickup device and determines whether the micromirror device is non-defective or defective. In the micromirror device sorting apparatus according to claim 3,
A micromirror device sorting apparatus comprising a display system for displaying the diffracted light distribution image and the determination result. In the micromirror device sorting apparatus according to claim 3,
The illumination system includes a wedge glass and a right angle prism. A maskless exposure apparatus that projects a pattern generated by a micromirror device onto a substrate with a projection lens,
An illumination system for illuminating the micromirror device with illumination light;
An image sensor;
A stage for moving the substrate and the imaging device;
When determining whether the micromirror device is good or defective, the stage is moved, the diffracted light from the micromirror of the micromirror device is incident on the image sensor, and the size of the diaphragm of the illumination system is controlled. A control system to
A processing system for processing a diffracted light distribution image captured by the image sensor and determining whether the micromirror device is a good product or a defective product based on a processing result of the diffracted light distribution image. Maskless exposure device. The maskless exposure apparatus according to claim 6.
A maskless exposure apparatus comprising a display system for displaying the diffracted light distribution image and the determination result. The maskless exposure apparatus according to claim 6.
The radius of the diaphragm of the illumination system when determining whether the micromirror device is good or defective is f for the focal length of the collimating lens of the illumination system, λ for the wavelength of the illumination light, and micro of the micromirror device. A maskless exposure apparatus characterized in that when the pitch of the mirror is P, it is smaller than λ · f / P.