JP2008193008A - Solid-state imaging device and manufacturing method thereof - Google Patents

Abstract

In a solid-state imaging device including a plurality of light receiving portions arranged in a matrix, and a color filter and a microlens array formed corresponding to the light receiving portions, color mixing due to light incident on adjacent color cells is performed. Suppress and reduce line shading.
A color filter 10 includes cyan (hereinafter referred to as CA) cells and yellow (hereinafter referred to as YE) cells alternately arranged in odd rows when viewed in a fixed direction, and magenta (hereinafter referred to as MG) cells and green (in the even rows). GR) cells are alternately arranged, and the order of arrangement of MG cells and GR cells is formed in a different complementary color difference sequential arrangement between even rows adjacent to each other, and the lower surface of at least one of CA cells and YE cells is MG The cell and the GR cell are configured so as to be positioned in the light receiving portion photodiode 2 from the lower surface. Here, the color cells 10a and 10c arranged in the concave portion 9A of the planarizing layer 9 are CA cells and YE cells, and the color cells 10b and 10d arranged in the convex portion 9B are lines even if incident light is mixed in color. MG cells and GR cells that do not cause shading.
[Selection] Figure 1

Description

  The present invention relates to a solid-state imaging device having a light receiving portion and a color filter on a semiconductor substrate, and a method for manufacturing the same.

  Digital still cameras, video cameras, and the like are required to have higher resolution, and solid-state imaging devices used in these cameras are expected to further increase the number of pixels and miniaturization. Simultaneously with the miniaturization of the solid-state image pickup device, a short exit pupil distance between the camera lens and the solid-state image pickup device is also progressing.

  However, with the progress of pixel miniaturization and the increased incident angle of incident light with the shortening of the exit pupil between the camera lens and the solid-state imaging device, line shading, which is a striped image defect, occurs. It becomes easy. The cause of the occurrence of line shading is considered to be color mixing due to light incident on a certain color cell fading adjacent color cells.

  Diagonal light causes such color mixing and photosensitivity reduction, and as a countermeasure, the distance from the surface of the semiconductor substrate (light receiving portion) to the bottom surface of the microlens is shortened. For this reason, a reduction in the thickness of the color filter is also being studied. However, in the complementary color filter, the green cell has a laminated structure of a cyan cell and a yellow cell, so that the film thickness increases to some extent.

  As a solution to this, for a color filter having a laminated structure, a color filter film not containing a photosensitive material component is formed and selectively etched to form a first color cell, on which a color filter film containing a photosensitive material component is formed. A method of forming and patterning by lithography to form a second-layer color cell is disclosed (for example, see Patent Document 1). According to this method, it is possible to reduce the thickness of both layers as compared with the case where the both layers are manufactured using a lithography method.

In addition, the lower surface of the green cell is placed closer to the light receiving part than the lower surface of other color cells, rather than reducing the thickness, thereby suppressing the protruding degree of the green cell and shortening the distance between the light receiving part and the microlens. Is disclosed (see, for example, Patent Document 2).
JP 2001-249218 A JP 2002-184965 A

  However, even if the color filter is made thinner as described above, there is a limit because the film thickness of the coloring material (pigment, dye) for color development is necessary. It is difficult to suppress color mixing with.

  In addition, the method of disposing the lower surface of the green cell closer to the light receiving part than the lower surface of the cells of other colors is only considered to shorten the distance between the microlens and the light receiving part. It is presumed that color mixing due to glaze still occurs.

  In view of the above problems, an object of the present invention is to provide a solid-state imaging device that suppresses color mixing due to light incident on adjacent color cells and hardly generates line shading.

  In order to solve the above-described problem, a solid-state imaging device according to the present invention includes a plurality of light-receiving units arranged in a matrix, and a color filter and a microlens array formed corresponding to the light-receiving units. In the apparatus, the color filter includes cyan cells and yellow cells alternately arranged in odd rows when viewed in a fixed direction, magenta cells and green cells alternately arranged in even rows, and the magenta cells and green cells. Of the cyan cells and the yellow cells are located closer to the light receiving unit than the lower surfaces of the magenta cells and the green cells. It is characterized by having a structure.

  Further, in a solid-state imaging device including a plurality of light receiving portions arranged in a matrix and a color filter and a microlens array formed corresponding to the light receiving portions, the color filters are viewed in a certain direction. Cyan cells and yellow cells are alternately arranged in odd-numbered rows, magenta cells and green cells are alternately arranged in even-numbered rows, and the complementary color difference sequential arrangement is different between the odd-numbered rows adjacent to each other. The lower surface of at least one of the magenta cell and the green cell is positioned closer to the light receiving part than the lower surfaces of the cyan cell and the yellow cell.

  Furthermore, in the solid-state imaging device including a plurality of light receiving portions arranged in a matrix, and a color filter and a microlens array formed corresponding to the light receiving portions, the color filters are formed in a primary color Bayer array. The lower surface of at least one of the blue cell and the red cell is positioned closer to the light receiving part than the lower surface of the green cell.

  In the method for manufacturing a solid-state imaging device according to the present invention, when manufacturing any one of the above-described solid-state imaging devices, a planarizing material is applied onto a semiconductor substrate on which a plurality of light receiving portions are formed, and the planarizing material is predetermined. By forming a concave portion by a lithography method using a gray scale mask at the color cell position, or by patterning the convex portion by a lithography method at a predetermined color cell position after applying a transparent resin on the planarizing material, A step of forming a planarization layer having concave and convex portions on the surface and a step of forming color cells in a predetermined arrangement on the concave and convex portions of the planarization layer are performed.

  In the step of forming the color cells in a predetermined arrangement, a first color resist is applied to the surface of the planarizing layer, and a desired film thickness is formed on the concave and convex portions of the planarizing layer by lithography using a gray scale mask. A first color resist layer is formed, and then a second color resist is applied on the first color resist layer, and the first color resist layer on the convex portion is formed by a lithography method using a gray scale mask. Patterning the second color resist layer to form a color cell made of the first color resist layer in the concave portion, and forming the first color resist layer and the second color resist layer in the convex portion. It is possible to form a color cell having a multilayer structure, which is convenient.

  In the solid-state imaging device according to the present invention, the lower surface of the predetermined color cell is positioned closer to the light receiving unit than the lower surface of the other color cell in the color filter configured by the complementary color difference sequential array or the primary color Bayer array. As a result, it is possible to suppress the incidence of light to adjacent color cells and the resulting color mixture, thereby suppressing the occurrence of line shading.

Embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows the configuration of a solid-state imaging device according to the first embodiment of the present invention. FIG. 1A is a schematic top view showing a planar arrangement of color filters of the solid-state imaging device. FIGS. 1B and 1C are respectively A-A in FIG. 1A of the solid-state imaging device. It is sectional drawing in a 'line and BB' line.

  In this solid-state imaging device, as shown in FIG. 1A, a cyan (denoted as CA) filter, a magenta (denoted as MG) filter, a yellow (denoted as YE) filter, and a green (denoted as GR) filter are provided. These are arranged so as to constitute a complementary color difference sequential arrangement. These color filters correspond to a plurality of photodiodes 2 arranged in a matrix on a semiconductor substrate 1 described later.

  Specifically, YE cells and CA cells are arranged in odd-numbered rows (referred to as odd-numbered rows) along the V-transfer direction (vertical transfer direction) for transferring charge signals, and are arranged in even-numbered rows (referred to as even-numbered rows). An MG cell and a GR cell are arranged. Further, in order to enable reading to the transfer circuit (CCD), “GR, MG,...” “MG, GR” alternately between adjacent even rows of MG cells and GR cells arranged in even rows. ,..., The arrangement order is changed.

  Referring to FIGS. 1B and 1C, a plurality of photodiodes 2 and transfer channels (not shown) are formed on a semiconductor substrate 1 such as silicon, and an insulating film such as a silicon oxide film is formed on the substrate surface. 3 is formed, a transfer electrode 4 is formed on the transfer channel via the insulating film 3, and an insulating film 5 covering the transfer electrode 4 is formed.

  Further, a light shielding film 6 is formed on the insulating film 5 so as to cover the transfer electrode 4 and have an opening for exposing the photodiode 2, and a planarizing layer 7 for filling the opening of the light shielding film 6 and planarizing the surface. An inner lens 8 is formed on the planarizing layer 7 so as to be above the photodiode 2.

  Further, the planarization layer 9 is formed so as to reduce the unevenness due to the inner lens 8, and the color filter 10 is formed on the planarization layer 9 so as to be above the photodiode 2, and the unevenness due to the color filter 10 is reduced. Thus, the planarizing layer 11 is formed, and the microlens 12 is formed on the planarizing layer 11 so as to be above the photodiode 2.

  A major feature of this solid-state imaging device is that concave portions 9A and convex portions 9B corresponding to the respective photodiodes 2 are formed on the surface of the flattening layer 9, and color cells 10a, 10b, 10c, and 10d are formed on the concave portions 9A and 10d, respectively. Is the point where is placed.

  The color cells 10a and 10c arranged in the recess 9A are CA cells or YE cells. The color cells 10b and 10d arranged on the convex portion 9B are MG cells or GR cells.

The reason why the color filter 10 is arranged as described above will be described.
In the above-described complementary color difference sequential arrangement, there are two types of GRs: a GR cell (denoted as GRc) adjacent to the CA cell and MG cell, and a GR (denoted as GRy) cell adjacent to the YE cell and MG cell. There is a GR cell. As for MG, there are two types of MG cells, MG (denoted as MGy) cell adjacent to the YE cell and GR cell, and MG (denoted as MGc) cell adjacent to the CA cell and GR cell. As described above, regarding MG and GR, the presence of two types of cells having the same color but different adjacent cells causes the occurrence of line shading.

The reason why line shading occurs is as follows.
Light that is supposed to be incident on the GRc cell causes color mixing by fainting the adjacent CA cell or MG cell. The light that should enter the Gry cell causes color mixing by fading the adjacent cells such as the YE cell and the MG cell. Further, the CA cell and the YE cell that are not common between the adjacent cell of the GRc cell and the adjacent cell of the Gry cell have different film thicknesses and colors. As a result, the degree of color mixing is different, and a sensitivity difference occurs between the GRc cell and the Gry cell. The same applies to the MG cell, and a difference in sensitivity occurs between the MGc cell and the MGy cell due to the difference between adjacent cells. Due to this difference in sensitivity, a difference in sensitivity between adjacent lines occurs, resulting in line shading.

  On the other hand, regarding CA, there is only a CA cell adjacent to the MG cell, the YE cell, and the GR cell. Regarding YE, there is only a YE cell adjacent to the MG cell, the GR cell, and the CA cell. As described above, regarding CA and YE, there is no cell having the same color and different adjacent cells. Therefore, there is no color mixing difference caused by the incident light grazing the adjacent cell, and no sensitivity difference occurs.

  In general, it is effective to reduce the thickness of adjacent cells, which is the cause of the difference in sensitivity, in order to reduce the color mixture that occurs when incident light glazes adjacent cells. There are limits.

  Therefore, in the complementary color difference sequential arrangement shown in FIG. 1A, at least of the adjacent CA cell and YE cell that cause a difference in sensitivity in each of MG and GR while reducing the thickness. The lower surface of one color is positioned closer to the light receiving unit (photodiode 2) than the lower surfaces of the MG cell and the GR cell.

This will be specifically described with reference to FIG.
FIG. 2A shows a conventional color filter structure. The surface of the flattening layer 9 is literally flat, and the color cells 10a, 10b, and 10c are arranged thereon. As shown in the figure, incident light incident on the color cell 10b grazes the adjacent color cell 10c, and color mixing occurs.

  In contrast, in the color filter structure of the present invention described with reference to FIG. 1, as shown in FIG. 2B again, the planarizing layer 9 is provided with convex portions 9B and concave portions 9A, and the lower surface of the color filter 10c. Is arranged closer to the light receiving part than the lower surface of the color filter 10b, the incident light entering the color cell 10b is less likely to fade the color cell 10c, color mixing can be reduced, and line shading can be reduced. The step between the concave portion 9A and the convex portion 9B is desirably 0.2 to 1 μm. The depth of the recess 9A may be different between that for CA and that for YE.

The main steps of the method for manufacturing the solid-state imaging device of FIG. 1 will be described.
As shown in FIG. 3 (a), a planarizing material 9 'made of acrylic resin or the like is applied so as to reduce unevenness due to the inner lens 8, and this planarizing material 9' is shown in FIG. 3 (b). Exposure is performed using a gray scale mask 21 having a transmittance distribution (a chrome layer of the mask is shaded) and developed to form a recess 9A at a predetermined position as shown in FIG. By leaving the convex portion 9B between them, the planarizing layer 9 having the concave portion 9A and the convex portion 9B corresponding to each photodiode 2 on the surface is formed.

  Alternatively, as shown in FIG. 4A, a planarizing material 9 ′ such as an acrylic resin is applied so as to reduce unevenness due to the inner lens 8 and is thermally cured at 180 ° C. to 260 ° C. If flatness cannot be obtained by only one application, the planarizing material 9 'is applied and thermally cured a plurality of times, and then thinned by dry etching until the desired planarization layer thickness is obtained. Further, after that, a photosensitive material 9 ″ made of acrylic resin or the like is further applied as shown in FIG. 4B, and patterning is performed by photolithography as shown in FIG. Then, the convex portion 9B is formed, and thereby the planarizing layer 9 having the concave portion 9A and the convex portion 9B corresponding to each photodiode 2 on the surface is formed.

  Alternatively, in the same manner as described above, the planarizing material 9 ′ is applied and heat-cured as many times as necessary, and is thinned by dry etching until a desired planarizing layer thickness is obtained, and then a photosensitive resin is applied, A pattern having an opening at a predetermined position is produced by photolithography, and a concave portion 9A is produced by dry etching using the pattern as a mask. By removing the pattern, the planarizing layer 9 having the concave portion 9A and the convex portion 9B on the surface is formed. Form.

Next, a method for manufacturing a green cell (a laminated structure of a cyan cell and a yellow cell) of a complementary color filter will be described.
As shown in FIG. 5A, a cyan resist 101 is applied by spin coating on the planarizing layer 9 having the concave portions 9A and the convex portions 9B formed on the surface as described above. Is exposed and developed using a gray scale mask 22 having a transmittance distribution shown in FIG. 5B (a chrome layer of the mask is shaded). As a result, as shown in FIG. 5C, cyan cells 102 having optimum film thicknesses are formed in one step for each of the concave portions 9A and the convex portions 9B. After that, as shown in FIG. 5D, the yellow cell 103 is formed on the convex portion 9B by the same method as the cyan cell 102. As a result, a cyan filter composed of the cyan cells 102 and a green cell formed by stacking the cyan cells 102 and the yellow cells 103 are formed.

  On the other hand, if a green cell is disposed on the convex portion 9B of the planarizing layer 9 and a cyan cell is disposed on the concave portion 9A, it is necessary to form cyan cells on both the convex portion 9B and the concave portion 9A. When a cyan resist is applied to the surface of the planarized layer 9 with unevenness, the cyan resist film thickness of the convex portion 9B becomes thin and the cyan resist film thickness of the concave 9A portion becomes thick. When photolithography is performed using a binary mask, the difference in resist film thickness between the convex portion 9B and the concave portion 9A generated during coating is transferred even after photolithography. In order to obtain a desired transmission spectrum, it is indispensable to control the cyan film thickness of the cyan cell and the cyan film thickness of the green cell (laminated structure of cyan cell and yellow cell). It is difficult to obtain an optimum cyan film thickness for both the green cell and the cyan cell in the recess 9A.

Each of the cyan cell, magenta cell, and yellow cell can be obtained by coating each photosensitive color material and patterning it by photolithography.
(Second Embodiment)
FIG. 6 shows a configuration of a solid-state imaging device according to the second embodiment of the present invention. FIG. 6A is a schematic top view showing a planar arrangement of the color filters of the solid-state imaging device, and FIGS. 6B and 6C are CC views in FIG. 6A of the solid-state imaging device, respectively. It is sectional drawing in a 'line and DD' line. In the figure, the same components as those in FIG.

  In this solid-state imaging device, a complementary color difference sequential arrangement is configured as in the solid-state imaging device of the first embodiment, YE cells and CA cells are arranged in odd rows along the V transfer direction, and even rows are arranged. An MG cell and a GR cell are arranged. However, unlike the first embodiment, in order to enable reading to the transfer circuit (CCD), for the YE cells and CA cells arranged in the odd rows, “YE, The arrangement order is changed so that “CA,...” “CA, YE,.

  Therefore, in this color difference sequential arrangement, two types of CAs, CA (adjacent to CAm) adjacent to the YE cell and MG cell, and CA (abbreviated to CAg) adjacent to the YE cell and GR cell are associated with CA. A cell exists. Regarding YE, there are two types of YE cells: a YE (YEg) cell adjacent to the CA cell and the GR cell, and a YE (YEm) cell adjacent to the CA cell and the MG cell. Thus, for CA and YE, the presence of two types of cells that are the same color but have different neighboring cells causes color mixing differences, sensitivity differences, and line shading for the same reason as described above. .

  For this reason, the lower surface of at least one color among the adjacent cells MG and GR that cause a sensitivity difference between CA and YE is arranged closer to the light receiving unit (photodiode 2) than the lower surface of MG and GR.

That is, the color cells 10b and 10d arranged in the recess 9A are MG cells or GR cells. As a result, it is possible to reduce color mixing that occurs when light incident on CA and YE grazes adjacent cells GR and MG. The color cells 10a and 10c arranged on the convex portion 9B are CA cells and YE cells that do not cause line shading even when incident light is mixed. The step between the concave portion 9A and the convex portion 9B is desirably 0.2 to 1 μm. The depth of the recess 9A may be different between the one for MG and the one for GR.
(Third embodiment)
FIG. 7 shows a configuration of a solid-state imaging apparatus according to the third embodiment of the present invention. FIG. 7A is a schematic top view showing a planar arrangement of the color filters of the solid-state imaging device, and FIGS. 7B and 7C are respectively EE in FIG. 7A of the solid-state imaging device. It is sectional drawing in a 'line and FF' line. In the figure, the same components as those in FIG.

  In this solid-state imaging device, as shown in FIG. 7A, a red (denoted as R) filter, a green (denoted as G) filter, and a blue (denoted as B) filter are arranged to constitute a Bayer array. ing. The Bayer array is an array in which B and R filters (cells) are formed between checkered arrays of G filters (cells).

  In this Bayer arrangement, in each G cell, the adjacent cells are the same as the R cell and the B cell. However, there are two types of G cells with different directions adjacent to the R cell and the B cell. That is, one G (Gr) cell is adjacent to the R cell in the row direction (V transfer direction) and adjacent to the B cell in the column direction, while the other G (Gb) cell is adjacent to the row. Adjacent to the B cell in the direction and adjacent to the R cell in the column direction.

  In such an arrangement, the influence of the shape of the opening of the light-shielding film 6 and the vertical and horizontal dimensions of the cell size causes color mixing caused by glazing adjacent cells in the row direction, and phasing the cells adjacent in the column direction. The mixed color will be different. Therefore, a sensitivity difference occurs between the Gr cell and the Gb cell, resulting in line shading.

  For this reason, the lower surface of at least one of the adjacent R cells and B cells that cause a difference in sensitivity between Gr and Gb is disposed closer to the light receiving unit (photodiode 2) than the lower surfaces of the Gr cell and Gb cell. The

That is, the color cells 10e and 10g arranged in the recess 9A are R cells or B cells. As a result, it is possible to reduce color mixing that occurs when light incident on the Gr cell and Gb cell grazes the adjacent R cell and B cell. The color cell 10f disposed on the convex portion 9B is a Gr cell or Gb cell that does not cause line shading even when incident light is mixed. The step between the concave portion 9A and the convex portion 9B is desirably 0.2 to 1 μm. There may be a difference in depth between the concave portion 9A and the concave portion 9A.
(Fourth embodiment)
FIG. 8 shows the configuration of a solid-state imaging device according to the fourth embodiment of the present invention.

The color filter structure according to the present invention, specifically, the color filter structure described in the third embodiment is applied to a MOS type solid-state imaging device (CMOS sensor).
As shown in the figure, in a MOS type solid-state imaging device, multilayer wiring of two or more layers is often formed in a pixel. 13 is an interlayer insulating film, 14 is a wiring, 15 is a conductive plug, 16 is a read gate, and 17 is an antireflection laminated film.

  Therefore, in general, the distance between the photodiode 1 and the microlens 12 is longer than that of the CCD solid-state imaging device. For this reason, when such a color filter structure is used in a MOS type solid-state imaging device (CMOS sensor), the effect of reducing defects such as line density defects is greater than when it is used in a CCD type solid-state imaging device.

The color filter structure described in the first and second embodiments is not limited to the color filter structure used here, and the MOS type solid-state imaging device (CMOS sensor) can also be used.
In the first to fourth embodiments described above, it is illustrated and described as having an upwardly convex inner lens 8, but may have a downwardly convex inner lens. May not have an inner lens.

  According to the present invention, it is possible to reduce the line density defect of the solid-state imaging device, which is useful for a digital still camera, a video camera or the like equipped with such a solid-state imaging device.

1 is a configuration diagram of a solid-state imaging device according to a first embodiment of the present invention. Sectional drawing explaining the principle which can reduce line shading with the solid-state imaging device of FIG. Sectional drawing which shows the 1st manufacturing method which manufactures the planarization layer in the solid-state imaging device of FIG. Sectional drawing which shows the 2nd manufacturing method which manufactures the planarization layer in the solid-state imaging device of FIG. Sectional drawing which shows the method of manufacturing the color filter in the solid-state imaging device of FIG. The block diagram of the solid-state imaging device concerning the 2nd Embodiment of this invention Configuration diagram of a solid-state imaging device according to a third embodiment of the present invention Configuration diagram of a solid-state imaging device according to a fourth embodiment of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor substrate 2 Photodiode 3 Insulating film 4 Transfer electrode 5 Insulating film 6 Light shielding film 7 Flattening layer 8 Inner lens 9 Flattening layer 9A Concave part 9B Convex part 10 Color filter 10a-10d Color cell (complementary color)
10e-10g color cell (primary color)
11 Flattening layer 12 Microlens

Claims (5)

  In a solid-state imaging device comprising a plurality of light receiving portions arranged in a matrix, and a color filter and a microlens array formed corresponding to the light receiving portions, the color filters are odd numbers when viewed in a certain direction. Cyan cells and yellow cells are alternately arranged in rows, magenta cells and green cells are alternately arranged in even rows, and the order of arrangement of the magenta cells and green cells is different between the even rows adjacent to each other. A solid-state imaging device, wherein a lower surface of at least one of the cyan cell and the yellow cell is located closer to a light receiving part than lower surfaces of the magenta cell and the green cell.   In a solid-state imaging device comprising a plurality of light receiving portions arranged in a matrix, and a color filter and a microlens array formed corresponding to the light receiving portions, the color filters are odd numbers when viewed in a certain direction. Cyan cells and yellow cells are alternately arranged in rows, magenta cells and green cells are alternately arranged in even rows, and the complementary color difference sequential arrangement is different between the odd rows in which the cyan cells and yellow cells are adjacent to each other. A solid-state imaging device, wherein the lower surface of at least one of the magenta cell and the green cell is positioned closer to the light receiving unit than the lower surfaces of the cyan cell and the yellow cell.   In a solid-state imaging device including a plurality of light receiving portions arranged in a matrix, and a color filter and a microlens array formed corresponding to the light receiving portions, the color filters are formed in a primary color Bayer array. A solid-state imaging device, wherein the lower surface of at least one of the blue cell and the red cell is located closer to the light receiving unit than the lower surface of the green cell.   4. The method of manufacturing a solid-state imaging device according to claim 1, wherein a planarizing material is applied on a semiconductor substrate on which a plurality of light receiving portions are formed, and a predetermined color of the planarizing material is formed. A concave portion is formed by a lithography method using a gray scale mask at a cell position, or the convex portion is patterned by a lithography method at a predetermined color cell position after applying a transparent resin on the planarizing material. A method of manufacturing a solid-state imaging device, comprising: forming a planarization layer having a concave portion and a convex portion; and forming a color cell in a predetermined arrangement on the concave portion and the convex portion of the planarization layer. .   In the step of forming the color cells in a predetermined arrangement, a first color resist is applied to the surface of the planarizing layer, and a desired film thickness is formed on the concave and convex portions of the planarizing layer by lithography using a gray scale mask. A first color resist layer is formed, and then a second color resist is applied on the first color resist layer, and the first color resist layer on the convex portion is formed by a lithography method using a gray scale mask. Patterning the second color resist layer to form a color cell made of the first color resist layer in the concave portion, and forming the first color resist layer and the second color resist layer in the convex portion. 5. The method of manufacturing a solid-state imaging device according to claim 4, wherein a color cell having a multilayer structure is formed.

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