JP5874209B2 - On-chip color filter for color solid-state image sensor - Google Patents

Description

  The present invention relates to a color filter used for a color solid-state imaging device and a manufacturing method thereof.

  In recent years, imaging devices have been widely used with the expansion of the contents of image recording, communication, and broadcasting. Various types of image pickup devices have been proposed. An image pickup device incorporating a solid-state image pickup device that has been stably manufactured with a small size, light weight, and high performance can be used as a digital camera or digital video. It has become widespread.

  The solid-state imaging device has a plurality of photoelectric conversion elements that receive an optical image from a subject and convert incident light into an electrical signal. The types of photoelectric conversion elements are roughly classified into CCD (charge coupled device) type and CMOS (complementary metal oxide semiconductor) type. In addition, there are two types of photoelectric conversion elements: linear sensors (line sensors) in which photoelectric conversion elements are arranged in a row, and area sensors (surface sensors) in which photoelectric conversion elements are two-dimensionally arranged vertically and horizontally. It is divided roughly into. In any sensor, the larger the number of photoelectric conversion elements (number of pixels), the more accurate the captured image.

  In addition, by providing a color filter in which a plurality of colored transparent patterns that selectively transmit light of a specific wavelength are arranged in the path of light incident on the photoelectric conversion element, the color information of the object can be obtained. A single-plate color solid-state imaging device that has been made possible is also widespread. An on-chip type color solid-state image sensor in which a color filter is directly formed on an array substrate of photoelectric conversion elements has become the mainstream for the purpose of reducing the thickness and weight of the color solid-state image sensor and increasing the definition. As the color of the color filter, three primary colors consisting of three colors of red (R), blue (B), and green (G), or cyan (C), magenta (M), and yellow (Y) are used. Complementary color systems are generally used, and in particular, the three primary color systems are often used.

  As shown in the schematic cross-sectional view of the color solid-state image sensor having the on-chip color filter, the color solid-state image sensor has an insulating layer on the array of photoelectric conversion elements 2 provided on the semiconductor substrate 1. The wiring layer 3 in which the wiring pattern is formed through 4 is laminated in multiple stages, and further, an electrode pad 5 for external connection is further exposed on the peripheral portion of the color solid-state imaging device. One flattening film 6 is formed, and a pixel pattern of each color composed of a colored transparent layer 7 is arranged on the first flattening film so as to correspond to the underlying photoelectric conversion element 2. The method of forming the pixel pattern of each color is that after the photosensitive colored resin of a specific color is dropped, the substrate is rotated to spread the coating uniformly and then the photosensitive colored resin is applied using an exposure mask having a predetermined pattern. In general, a method of repeatedly forming a colored transparent pattern by performing exposure to light and development is performed for each color.

  In order to increase the amount of information of an image taken with a solid-state imaging device that is as small as possible, it is necessary to miniaturize and highly integrate a photoelectric conversion device that serves as a light receiving unit. However, when the photoelectric conversion element is miniaturized, the area of each photoelectric conversion element is reduced, and the area ratio that can be used as the light receiving unit is also reduced. And the effective sensitivity decreases.

As a means for preventing such a decrease in sensitivity of the miniaturized solid-state imaging device, in order to efficiently capture light into the light receiving portion of the photoelectric conversion device, the light incident from the object is condensed and photoelectrically A technique for forming a microlens that leads to a light receiving portion of a conversion element has been proposed. As shown in FIG. 2A, the microlens 9 corresponding to the pixel pattern is formed on the colored transparent layer 7 through the second flattening film 8, and the microlens condenses light to perform photoelectric conversion. By guiding it to the light receiving portion of the element 2, it is possible to increase the apparent aperture ratio (area) of the light receiving portion, and it is possible to improve the sensitivity of the solid-state imaging device.

Further, when the color solid-state imaging device shown in FIG. 2A is miniaturized, the influence that a part of incident light is slightly obliquely incident cannot be ignored, and photoelectric conversion corresponding to each color pixel pattern of the colored transparent layer 7 is performed. Incident light enters adjacent elements other than the elements, and color mixing occurs. As a result, the color reproducibility of the color solid-state imaging device is significantly deteriorated.
In order to prevent color mixing and provide a color solid-state imaging device with good color reproducibility, as shown in FIG. 2B, a light shielding pattern 10 is formed between the pixel patterns of each color of the colored transparent layer 7. Has been proposed (see Patent Document 1).

  Considering the light condensing by the microlens, it is difficult to elongate the shape of the element, and increasing the number of photoelectric conversion elements corresponding to each of the three miniaturized pixels also has a manufacturing constraint. As shown in FIG. 3A, a checkered pattern called a Bayer pattern, as shown in FIG. 3A, is applied to a color filter to reduce the total number of pixels without reducing the apparent resolution. Yes. Here, one pixel corresponds to a color filter pixel of one color, and one set of four pixels (sets surrounded by a thick line in FIG. 3) in which two G (green) pixels are diagonally arranged is arranged. Repeatedly placed. In this arrangement, the total number of pixels N of the photoelectric conversion elements is N / 2 for G (green) and N / 4 for R (red) and B (blue). A set of N RGB is created by performing an interpolation operation using the output of surrounding pixels for each pixel. Here, the reason why the number of G (green) pixels is twice as large as that of other colors is that the resolution for G, which is highly visible to human eyes, increases the apparent resolution.

JP-A-2-304972

  In the production of an on-chip color filter, if a pixel of a colored transparent pattern is peeled off, it becomes a “white scratch” mode defect in a color solid-state imaging device. Also in the Bayer array shown in FIG. 3A, the possibility of the occurrence of defects increases with the miniaturization of the pattern. When a schematic cross-sectional view taken along the one-dot chain line yy ′ in FIG. 3A is shown in FIG. 3B, the colored transparent patterns 71 ( G), 72 (R), 71 (G), and 73 (B) are arranged in a plane. Since the transparent first planarizing film 6 similar to that in FIG. 2 has adhesion to other resins, an effect of preventing pixel peeling of the light-shielding pattern and the colored transparent pattern of each color can be expected, but FIG. As the film thickness / size ratio of the light shielding pattern and the colored transparent pattern of each color increases, pixel peeling tends to occur.

  In addition, the light-shielding pattern 10 is required to be remarkably miniaturized as compared with other types of patterns as the color solid-state imaging device is miniaturized. When the line width of the light-shielding pattern approaches 0.1 μm, for example, when an i-line stepper having a wavelength of 365 nm is used when forming the light-shielding pattern by a photolithography method, it becomes difficult to control the line width and peeling easily occurs. Become. As a result, color mixing may occur or the sensitivity difference between pixels may increase, and color reproducibility may deteriorate. Furthermore, the peeling of the light shielding pattern may give an opportunity to cause pixel peeling of the adjacent colored transparent pattern.

The present invention is proposed in view of the above problems, and a problem to be solved by the present invention is a pixel for use in a color solid-state imaging device having a light-shielding pattern between the pixels and having good color reproducibility. It is an object to provide an on-chip color filter having a good shape without peeling.

As a means for solving the above-mentioned problems, the invention according to claim 1 is characterized in that a light-shielding pattern and at least 3 are provided on the light-receiving surface side surface of a solid-state image sensor pixel portion in which a plurality of photoelectric conversion elements are arranged in a plane on a semiconductor substrate. In the color filter forming step of sequentially arranging the colored transparent pattern of the color by plane sequentially by color, the step of forming the initial light-shielding pattern with a black material so that the portion that becomes the pixel portion of the first color of the colored transparent pattern is an opening, A step of applying and curing a colored transparent material of the first color, a step of forming an etching resist pattern so as to selectively cover a region including all the portions to be the pixel portion of the first color, and being exposed to an opening of the etching resist pattern By removing the first colored transparent material and the underlying black material, applying the second colored transparent material, and photolithography. Thus, the second color transparent pattern is formed so as to be thicker than the first color transparent pattern and stacked on the light shielding pattern adjacent to the second color pixel part, and the third color pixel part is formed. The step of removing the colored transparent material of the second color applied to the portion, the step of applying the colored transparent material of the third color, and the photolithography method, coloring the first color to the portion that becomes the third color pixel portion of the colored transparent pattern Each step including a step of forming a colored transparent pattern of the third color so as to be thicker than the transparent pattern and stacked on the light shielding pattern adjacent to the pixel portion of the third color is performed in order. It is a manufacturing method of the on-chip color filter for color solid-state image sensors.
The invention described in claim 2 is the method for producing an on-chip color filter for a color solid-state image pickup device according to claim 1, wherein dry etching is used in the step of forming the initial light shielding pattern.
According to a third aspect of the present invention, the resist material used in the step of forming the etching resist pattern is a positive photosensitive resin. The on-state for the color solid-state imaging device according to the first or second aspect It is a manufacturing method of a chip color filter.
The invention described in claim 4 is characterized in that dry etching is used in the step of removing the colored transparent material of the first color exposed in the opening portion of the etching resist pattern and the black material thereunder. It is a manufacturing method of the on-chip color filter for color solid-state image sensors in any one of -3.
The invention according to claim 5 is the method for producing an on-chip color filter for a color solid-state imaging device according to claim 4, wherein an inorganic film is formed under the etching resist pattern.
The invention according to claim 6 is characterized in that the black material constituting the light-shielding pattern has carbon black, and the thickness of the light-shielding pattern is 0.05 to 0.3 μm. 5. A method for producing an on-chip color filter for a color solid-state imaging device according to any one of 5 above.
The invention according to claim 7 is characterized in that the material constituting the colored transparent pattern of a plurality of colors has a resin in which colored pigments of selected colors are dispersed. The manufacturing method of the on-chip color filter for color solid-state image sensors as described in 1 above.
The invention according to claim 8 is the color solid according to any one of claims 1 to 7, wherein the planar arrangement of the colored transparent patterns of a plurality of colors is a Bayer arrangement, and the first color is green. It is a manufacturing method of the on-chip color filter for image sensors.

  In the present invention, since the formation portion of the second and subsequent pixel portions of the on-chip color filter can be covered with an initial light-shielding pattern including a large area before application of the colored transparent material of the first color, it is miniaturized. It is possible to reduce the chance that the shading pattern is exposed to a long process and cause peeling, and an on-chip color filter having a good shape can be provided.

  Moreover, according to Claims 2-5 of this invention, the on-chip color filter of a further favorable shape can be provided. According to the sixth to tenth aspects of the present invention, an on-chip color filter having a better shape is provided with high resolution, and is optimally used as an element constituting a color solid-state imaging device having particularly good color reproducibility. be able to.

FIG. 6 is a schematic plan view (upper stage) for explaining the main steps of the present invention in the order of steps (a) to (d) and a schematic cross-sectional view (lower stage) taken along a dashed-dotted line x-x ′ at a corresponding position. It is a schematic cross-sectional view of a color solid-state imaging device having an on-chip color filter, where (a) shows a type without a light shielding pattern between pixel patterns, and (b) shows a type with a light shielding pattern between pixel patterns. It is a schematic diagram for demonstrating an example of the planar arrangement | sequence of an on-chip color filter, (a) is a top view which shows a set of pixel arrangement | sequence, (b) is along the dashed-dotted line yy 'in (a). FIG. It is comparison explanatory drawing of the method (a) by this invention and the conventional method (b) by the comparison of the initial light-shielding pattern. Schematic plan view (upper stage) for explaining the manufacturing procedure by the process after the second color for an example of the present invention, and a schematic cross-sectional view at a corresponding one-dot chain line xx ′ or zz ′ (lower stage) ). About other examples of the present invention, a schematic plan view (upper stage) for explaining a manufacturing procedure by the process after the 2nd color, and a schematic cross-sectional view at a corresponding one-dot chain line xx ′ or zz ′ (Lower). FIG. 7 is a schematic diagram for explaining an example of a planar arrangement of an on-chip color filter formed by the manufacturing procedure shown in FIG. 6, wherein (a) is a plan view showing a set of pixel arrangements, and (b) is (a) It is sectional drawing along the dashed-dotted line yy 'in FIG.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
FIG. 1 is a schematic plan view (upper stage) for explaining the main steps of the present invention in the order of steps (a) to (d), and a schematic cross-sectional view taken along one-dot chain line xx ′ at the corresponding position (lower stage). It is.

  In the present invention, a light-shielding pattern is formed on the light-receiving surface side surface of a solid-state imaging element pixel portion in which a plurality of photoelectric conversion elements 2 are arranged in a plane on the semiconductor substrate 1 in FIG. In the on-chip color filter forming process in which the 10 and the colored transparent layer 7 composed of a plurality of colored transparent patterns are sequentially arranged in a plane by color, an example in which the Bayer array pattern is formed is devised on the process. It explains according to. That is, in the present invention, the process of forming the initial light-shielding pattern 11 in FIG. 1 (a) with a black material so that the portion that becomes the pixel portion of the first color of the colored transparent pattern becomes the opening 12 is shown in FIG. A step of forming and curing an application layer 711 of colored transparent material of color, a step of forming an etching resist pattern 13 so as to selectively cover a region including all the portions to be the pixel portion of the first color in FIG. FIG. 1 (d) removes the colored transparent material of the first color exposed in the opening 14 of the etching resist pattern and the black material underneath it to provide a removal portion 15, thereby providing a portion that becomes the pixel portion of the second and subsequent colors. Each step including the step of preparing and shaping the light shielding pattern 10 is performed in order.

  The first planarizing film 6 provides a flat and uniform base for performing an on-chip color filter forming process on the region including the photoelectric conversion element 2, the wiring layer 3, and the insulating layer 4 in the lower layer. It is desirable to form a colorless and transparent film having a necessary minimum thickness. For example, a colorless and transparent acrylic resin solution is thinly applied to a thickness of 0.1 μm and heat-treated.

  As a method of forming the initial light-shielding pattern 11 with a black material as shown in FIG. 1A, general photolithography for selective exposure, development, and curing is performed after applying a material imparted with photosensitivity to the black material, drying it. Patterning can be performed directly by performing a statutory process. In addition, after forming a dry etching resist pattern on the surface obtained by applying and drying a black material that does not require photosensitivity by a photolithography method similar to the above, a fine pattern shape can be formed in a good state by the dry etching method. . The latter method is particularly suitable for the formation of a miniaturized pattern because the suitability for photolithography and the suitability for dry etching can be optimized by sharing the resist material and the black material. Further, in order to particularly reinforce the dry etching resistance, it is possible to form an inorganic film under the resist material and complete the dry etching of the black material into a more favorable shape.

  Next, as shown in FIG. 1B, a colored transparent material coating layer 711 of the first color is formed by means such as spin coating that can be applied uniformly. Thereafter, the etching resist pattern 13 is covered so as to cover at least all the portions to be the pixel portions of the first color, and the portions where the pixel portions for the second and subsequent colors are to be provided are openings 14 in the etching resist pattern. Are formed (see FIG. 1C). If the resist material used in the step of forming the etching resist pattern 13 is a positive photosensitive resin whose exposed portion is dissolved and removed by development, a light shielding portion is provided corresponding to the portion covered with the etching resist pattern 13 described above. Use a photomask.

  As the positive photosensitive resin, a material having high sensitivity and high resolution is practically used. For example, a novolak resin-based alkali-soluble photoresist can be used. A positive photosensitive resin is uniformly applied to the surface of the colored transparent coating layer 711 of the first color by means of spin coating or the like, dried, and then a portion corresponding to the portion of the pixel portion of the first color to be finally left is shielded from light Then, the portion corresponding to the location where the pixel portion for the second color and subsequent pixels where the colored transparent coating layer of the first color is to be removed is selectively exposed by a photomask having a light transmission portion. Details of various patterns around the pixel area that are formed at the same time as the on-chip color filter forming process are omitted, but depending on the necessity of subsequent processing removal, etc., it is necessary to avoid exposing the surface during the process. The corresponding part is shielded from light, and the part corresponding to the part where the surface is desired to be exposed can be included in the photomask pattern as a light transmission part. By developing with an alkaline solution after selective exposure using the photomask, the etching resist pattern 13 remains only in the portion corresponding to the light shielding portion of the photomask pattern, and the portion corresponding to the light transmitting portion of the photomask pattern is It becomes the opening 14 of the etching resist pattern.

  By using the positive photosensitive resin as a resist material used in the step of forming the etching resist pattern, the resist pattern can be formed in a good shape with a simple process with a small amount of light. Also, considering the resistance in the dry etching process described later, an inorganic film is formed under the resist material for the purpose of particularly reinforcing the dry etching resistance, and after the inorganic film is formed, the inorganic film is dried. It can also be used as a mask for etching to complete the dry etching of the colored transparent material of the first color and the underlying black material into a good shape.

Next, as shown in FIG. 1 (d), by removing the colored transparent material of the first color exposed in the opening 14 of the etching resist pattern and the black material under the first color, a removal portion 15 is provided, thereby providing the second color. It is possible to prepare locations for subsequent pixel portions and shape the light shielding pattern 10 together. Dry etching is suitable as the etching for forming the removal portion 15.
If the main material of the removed portion to be removed by dry etching is a resin, it is not limited to a normal dry etching apparatus, and an ashing apparatus that introduces oxygen gas can be used. In that case, the remaining etching resist is used. The pattern can be removed by the same apparatus. In general, the etching gas for removing the colored transparent material of the first color and the underlying black material can be switched to be optimized as necessary. The cross-sectional shape of the processed region is particularly suitable for processing a fine pattern because dry etching has a smaller shape defect factor such as side etching than dry etching.

As an example, after forming the initial light-shielding pattern 11 shown in FIG. 1A by a photolithography method using a material in which carbon black is dispersed in an acrylic resin-based photocurable resin as the black material in this example, As described above, the coating layer 711 of the first colored transparent material and the etching resist pattern 13 are sequentially formed, and the etching time is about 1 minute in an environment where CF ₄ gas is passed through the dry etching apparatus. As shown in d), the first colored transparent material and the underlying black material can be selectively removed.

  FIG. 4 is a comparative explanatory diagram of the method (a) according to the present invention and the conventional method (b) by comparing the initial light shielding patterns. Each upper stage is a plan view of an initial light-shielding pattern that is a base for forming a set of pixel arrays (Bayer array), and the lower stage is a cross-sectional view taken along the alternate long and short dash line x-x 'in the plan view.

  In the conventional method (b), a pattern having a necessary shape as the light-shielding pattern 10 is formed on the first planarizing film 6 from the beginning, and then the process of forming the colored transparent layer 7 is performed. In the present invention (a), unlike the final light-shielding pattern 10, an initial light-shielding pattern 11 is first formed in which a light-shielding portion made of a black material is left even at the pixel portion for the second and subsequent colors. For example, when the colored transparent pattern of the Bayer arrangement of this example is adopted, the plurality of sets of the arrangement shown in FIG. 4A are arranged in the same direction in the vertical direction and the horizontal direction, so that a plurality of sets are repeatedly arranged. The light shielding portions are adjacent to each other in the four directions, and the initial light shielding pattern 11 has a shape in which a thin line does not appear. Even in the case of a pattern that is not a Bayer array, the formation positions of the second and subsequent pixel portions of the on-chip color filter are covered with an initial light-shielding pattern including a large area before applying the colored transparent material of the first color. Therefore, it is possible to reduce the chance that the miniaturized light-shielding pattern is exposed to a long process and causes peeling.

  FIG. 5 is a diagram for explaining a manufacturing procedure according to the second and subsequent color steps after the order of the main steps (a) to (d) of the present invention shown in FIG. FIG. 6 is a schematic plan view (upper stage) and a schematic cross-sectional view (lower stage) taken along one-dot chain line xx ′ or zz ′ of a corresponding position. FIG. 5D shows the same diagram as FIG. 1D again.

  In this example, the colored transparent pattern 71 of the first color and the removal portion 15 are removed by the step of removing the colored transparent material of the first color exposed in the opening of the etching resist pattern and the underlying black material (FIG. 5D). Step of forming the second colored transparent pattern 72 by a photolithography method at the location that becomes the second color pixel portion of the colored transparent pattern (FIGS. 5E and 5F), On-chip for a color solid-state imaging device by sequentially performing the step (FIG. 5 (g)) of forming the third colored transparent pattern 73 by a photolithography method at a location that becomes the third color pixel portion of the colored transparent pattern A color filter can be manufactured.

  In the step of forming the colored transparent pattern 72 of the second color, first, a coating layer 721 of the colored transparent material of the second color is formed by means that can be applied uniformly such as spin coating (see FIG. 5E). As the colored transparent material for the second color, a material imparted with photosensitivity is used, and after application and drying, a general photolithography process of selective exposure, development, and curing is performed to directly form a pattern. Then, as shown in FIG. 5F, the second color pixel portion can be formed and aligned with a position where the pixel portion is to be provided. At this time, the colored transparent material of the second color applied to the place where the pixel portion of the third color is to be provided is removed by development, and the development removal unit 16 is provided. The colored transparent material of the second color imparted with photosensitivity is thermally cured after development, and with a slight shrinkage, the colored transparent material 72 of the second color having the same height as the colored transparent pattern 71 of the first color And can be stably formed side by side.

  As shown in FIG. 5G, the step of forming the third color transparent pattern 73 by the photolithography method at the location that becomes the pixel portion of the third color of the color transparent pattern forms the color transparent pattern 72 of the second color. By performing in the same manner as the step, the colored transparent layer of the Bayer array on-chip color filter in which the three colors are arrayed in a plane is completed.

  FIG. 6 is a drawing for explaining a manufacturing procedure in the second and subsequent steps after the order of the main steps (a) to (d) of the present invention shown in FIG. 1 in another example of the present invention. FIG. 6 is a schematic plan view (upper stage) and a schematic cross-sectional view (lower stage) taken along one-dot chain line xx ′ or zz ′ of the corresponding position. FIG. 6D shows the same diagram as FIG. 1D again.

  In this example, an on-chip color filter for a color solid-state imaging device can be manufactured by the same manufacturing method as the example described with reference to FIG. 5, but the second color transparent pattern 72 ′ and / or the third color transparent pattern The thickness of 73 'can be thicker than the colored transparent pattern 71 of the first color, and the light-shielding pattern 10 can be laminated on the adjacent light-shielding pattern 10. By realizing the configuration of this example, the contact area between the colored transparent pattern and the light-shielding pattern is increased, and the colored transparent pattern and the light-shielding pattern can be prevented from being peeled off in the manufacturing process, and can be peeled off due to stress after manufacturing. The prevention effect can be obtained.

  FIG. 7 is a schematic diagram for explaining an example of a planar arrangement of the on-chip color filter formed by the manufacturing procedure shown in FIG. 6, wherein (a) is a plan view showing a set of pixel arrangements; ) Is a cross-sectional view taken along the alternate long and short dash line yy ′ in FIG. As shown in FIG. 6, when the thicknesses of the colored transparent patterns of the three colors are not uniform, the role of the second planarizing film 8 in FIG. 7 becomes particularly important. That is, the second planarization film 8 can eliminate unevenness in the height of the colored transparent patterns of the three colors and provide a flat surface as a base for the microlens 9 provided in the upper layer. As an example of the second planarizing film 8, a colorless and transparent acrylic resin solution is applied and formed to a thickness of 0.2 μm, and is cured by heat treatment through exposure and development steps as necessary.

  The light-shielding pattern constituting the on-chip color filter of the present invention contributes to providing a color solid-state imaging device with good color reproducibility by preventing light mixture by blocking light between adjacent pixels. However, if there is a function for limiting the amount of light around the colored pixels in a good shape, not only a slight light transmission is an obstacle, but a certain light transmission is preferable for use as an alignment target pattern. The light transmittance for alignment is preferably 20% or more, and the light transmittance is desirably 70% or less in consideration of the originally required light shielding property.

Further, as the black material constituting the light-shielding pattern, it is appropriate to have carbon black that is easy to obtain and that can be easily mixed with a resin or a solvent and removed by dry etching. Although it depends on the light-shielding performance of the coating material obtained as a result of the blending, the thickness of the final light-shielding pattern will be the cause of defective defects if it is formed too thick in consideration of the pattern shape and laminated structure. Is preferably 0.05 to 0.3 μm. If the light-shielding pattern is too thin, the light-shielding property is generally insufficient, and if the light-shielding pattern is too thick, unevenness occurs particularly in the coating process and appears as unevenness after the pattern is formed.

  On the other hand, it is necessary to prepare a plurality of colors for the colored transparent pattern constituting the on-chip color filter of the present invention. The material used for forming the colored transparent pattern is preferably a coating material in which a color pigment obtained by obtaining a desired color with high color purity and brightness is dispersed in a resin. In addition, the material used for the colored transparent patterns of the second and third colors is preferably of a type that provides photosensitivity and can be directly exposed and developed by a photolithography method, according to the manufacturing method of the present invention. For example, a photo-curable negative resist in which a photopolymerization initiator or a solvent is added to an acrylic resin can be used. Since the material used for the colored transparent pattern of the first color is subjected to a manufacturing method in which an etching resist pattern is used as a mask after coating and formation, the colored transparent material itself does not necessarily need photosensitivity.

  In the on-chip color filter of the present invention, it is preferable that the planar arrangement of a plurality of colored transparent patterns is a Bayer array, and the first color is green. By adopting a Bayer array that reduces the total number of pixels without reducing the apparent resolution, a high-resolution color solid-state imaging device can be provided as compared with the same miniaturization process. In addition, in the Bayer array, green, which has a large number of pixels, is adopted as the first color, thereby further preventing peeling of the light shielding pattern processed from the initial light shielding pattern and peeling of the colored transparent pattern laminated on the light shielding pattern around each pixel. can do.

DESCRIPTION OF SYMBOLS 1 ... Semiconductor substrate 2 ... Photoelectric conversion element 3 ... Wiring layer 4 ... Insulating layer 5 ... Electrode pad 6 ... First planarization film 7 ... Colored transparent layer 8 .... Second planarizing film 9 ... micro lens 10 ... light shielding pattern 11 ... initial light shielding pattern 12 ... opening 13 of initial light shielding pattern ... etching resist pattern 14 ... etching resist Pattern opening 15 ... removal part 16 ... development removal part 71 ... colored transparent pattern 72 of the first color ... colored transparent pattern 73 of the second color 73 ... colored transparent pattern 711 of the third color -Colored transparent coating layer 721 for the first color ... Colored transparent coating layer for the second color

Claims (8)

In a color filter forming step in which a light-shielding pattern and at least three colored transparent patterns are sequentially arranged in a plane on the light-receiving surface side surface of a solid-state imaging element pixel unit in which a plurality of photoelectric conversion elements are arranged in a plane on a semiconductor substrate,
A step of forming the initial light-shielding pattern with a black material so that the portion to be the pixel portion of the first color of the colored transparent pattern is an opening,
Applying and curing the first colored transparent material;
Forming an etching resist pattern so as to selectively cover a region including all portions to be the pixel portion of the first color;
Removing the first color transparent material exposed in the opening of the etching resist pattern and the underlying black material;
Applying a second transparent coloring material;
By forming the second color transparent pattern so as to be thicker than the first color transparent pattern and to be laminated on the light shielding pattern adjacent to the second color pixel portion by photolithography, the third color pixel Removing the colored transparent material of the second color applied to the part to be a part,
Applying a third color transparent material;
3 so that it is thicker than the colored transparent pattern of the first color and is also laminated on the light shielding pattern adjacent to the pixel portion of the third color by photolithography. Forming a colored transparent pattern of eyes,
A method for producing an on-chip color filter for a color solid-state imaging device, wherein the steps including the steps are sequentially performed.   The method for producing an on-chip color filter for a color solid-state imaging device according to claim 1, wherein dry etching is used in the step of forming the initial light-shielding pattern.   The method for producing an on-chip color filter for a color solid-state imaging device according to claim 1 or 2, wherein the resist material used in the step of forming the etching resist pattern is a positive photosensitive resin.   The color solid-state imaging according to any one of claims 1 to 3, wherein dry etching is used in the step of removing the colored transparent material of the first color exposed in the opening of the etching resist pattern and the black material thereunder. Manufacturing method of on-chip color filter for device. 5. The method for producing an on-chip color filter for a color solid-state imaging device according to claim 4, wherein an inorganic film is formed under the etching resist pattern. Black material constituting the light-shielding pattern has a carbon black, a color solid-state imaging device according to claim 1, the thickness of the light-shielding pattern is characterized in that it is a 0.05~0.3μm Method for on-chip color filter for use . The on-chip color for a color solid-state imaging device according to any one of claims 1 to 6, wherein the material constituting the colored transparent pattern of a plurality of colors has a resin in which colored pigments of selected colors are dispersed. A method for manufacturing a filter. The method for producing an on-chip color filter for a color solid-state image pickup device according to any one of claims 1 to 7 , wherein the planar arrangement of the colored transparent patterns of a plurality of colors is a Bayer array, and the first color is green .