JP2004200360A - Solid-state imaging device and method of manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid-state imaging element having the function to cut the light in the infrared region, which does not require a thick infrared cutting filter and improves light collection property, an S/N by reducing the reflected light, and quality of image, and also to provide a method of manufacturing the same solid-state imaging element. <P>SOLUTION: A micro lens 39 and a flat layer 34 have the infrared absorbing function. A method of manufacturing the solid-state imaging element comprises the steps of (1) forming a flat layer 34 having the infrared absorbing function on a photo-electric conversion element 32, (2) forming a color filter layer 33, (3) forming an infrared absorbing layer 35, (4) forming a lens mother die 20 with the photolithography and heat treatment, and (5) converting the infrared absorbing layer into a micro lens 39 having the infrared absorbing function by conducting the dry-etching and transferring a lens mother pattern to the infrared absorbing layer. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a solid-state imaging device typified by a C-MOS or a CCD, and in particular, can reduce the size of an optical system of a camera without impairing color reproducibility, and improve light condensing and S / S The present invention relates to a solid-state imaging device capable of improving an N ratio and improving image quality.
[0002]
[Prior art]
A solid-state image sensor having a photoelectric conversion element such as a C-MOS or CCD mounted on a camera has a primary color (RGB) system or a complementary color (YMC) on the photoelectric conversion element in order to perform color separation at the time of imaging. An organic color filter layer of three primary colors is provided.
However, the photoelectric conversion element has high sensitivity outside the human visible region (400 nm to 700 nm), that is, also in the long wavelength infrared region (700 nm to 1100 nm). There is no function of cutting light in the infrared region, and therefore, light having a long wavelength of 700 nm or more enters the photoelectric conversion element, and accurate color separation is not performed.
[0003]
In order to avoid this inaccurate color separation, for example, a reflection type infrared cut filter using an inorganic multilayer film and an absorption type infrared cut filter using inorganic glass or organic dye containing metal ions are inserted into the optical system of the camera. That is the current situation.
The reflection type infrared cut filter made of inorganic multilayer film has a high function to cut the light in the infrared region for the incident light from the direction perpendicular to the surface, but it is red for the incident light from the oblique direction. The function of cutting light in the outer region is insufficient. To compensate for this, an absorption-type infrared cut filter is used in combination to eliminate the effects of oblique incidence and re-incidence of light in the infrared region.
Further, these infrared cut filters are incorporated in an optical system as members of a camera, but have a thickness of 1 to 3 mm, respectively, and have been problematic in terms of miniaturizing the camera and from the viewpoint of cost.
[0004]
A well-known technique relating to a microlens forming technique is disclosed in, for example, Japanese Patent Application Laid-Open No. Sho 60-53073 in relatively detail. Japanese Patent Application Laid-Open No. Sho 60-53073 discloses a technique for forming a lens into a round and hemispherical shape, a technique using thermal fluidity (heat flow) of a resin by heat, and a method of processing a lens by several etching methods. The technology is also disclosed in detail.
[0005]
In addition, as a measure to reduce the loss of light-collecting performance due to light scattering on the lens surface, an organic film such as polyglycidyl methacrylate (PGMA) or an OCD (for forming an SiO ₂ -based film manufactured by Tokyo Ohka Kogyo Co. A technique for forming an inorganic film of a coating liquid) is also disclosed.
In addition to the technique described above, a detailed description of a technique for dry-etching a microlens is described in Japanese Patent Application Laid-Open No. Hei 1-106666.
[0006]
[Patent Document 1]
JP-A-60-53073 [Patent Document 2]
JP-A-1-106666
[Problems to be solved by the invention]
The present invention has been made in view of the above-described problems, and has a function of cutting light in an infrared region without increasing the thickness of an optical system of a camera. Well, it is something that is kept in an optimized state.
That is, a first object of the present invention is to provide a thin solid-state imaging device which does not require an infrared cut filter having a thickness of about 1 mm to 3 mm.
[0008]
FIG. 8 is a cross-sectional view illustrating an example of a solid-state imaging device according to a known technique. As shown in FIG. 8, on the photoelectric conversion element (82), flattening layers (84) and (85), a color filter layer (83), and optionally an inner lens are formed. It is a relatively large (thicker) lens lower distance (78).
Usually, the microlens (89) is formed of a high refractive index resin having a refractive index of about 1.6 to 1.7. An effective means for improving the S / N (signal / noise) ratio in the conversion element (82) is to reduce (thin) the distance under the lens (78).
A second object of the present invention is to reduce the distance under the lens and improve the light collecting property and the S / N ratio.
[0009]
FIG. 4A is a plan view of another example of the solid-state image sensor from the microlens side, and FIG. 4B is a cross-sectional view taken along line BB in FIG. 4A. .
When the pitch and the size of the photoelectric conversion elements (52) are fine pitches, for example, 3 μm or less, the influence of the reflected light from the non-opening portion (gap between microlenses) (49) between the microlenses (55) increases. The reflected light is re-reflected by the cover glass disposed on the upper surface of the solid-state imaging device, and further by the optical lens group thereon, and re-enters another adjacent photoelectric conversion device, thereby causing noise that leads to deterioration of image quality. It becomes light.
[0010]
Further, the microlens in the solid-state imaging device shown in FIG. 8 is a microlens formed by a heat flow, but a microlens formed by a heat flow method generally has a high refractive index and reflects light reflected from the surface of the microlens. The amount was also quite large, causing a decrease in image quality.
A third object of the present invention is to minimize reflection light from the non-opening (49) between the microlenses shown in FIG. 4 and the surface of the microlenses (89) shown in FIG. The object is to improve the image quality by improving the / N ratio.
[0011]
That is, the present invention relates to a solid-state imaging device having a function of cutting light in an infrared region, eliminating the need for a thick infrared cut filter, and reducing the distance below the lens to collect light. Further, it is an object of the present invention to provide a solid-state image pickup device having improved image quality, improved S / N ratio, improved S / N ratio by reducing light reflected from the non-opening portion and the surface of the microlens, and improved image quality. It is assumed that.
Another object is to provide a manufacturing method thereof.
[0012]
[Means for Solving the Problems]
The present invention provides a solid-state imaging device in which at least a flattening layer, a color filter layer, and a substantially hemispherical microlens are sequentially arranged as constituent elements on a plurality of photoelectric conversion elements. The solid-state imaging device is characterized in that the flattening layer has an infrared absorbing function.
[0013]
Further, the present invention is the solid-state imaging device according to the above invention, wherein an ultraviolet absorbing layer is provided between the flattening layer and the color filter layer.
[0014]
Further, the present invention provides a method for manufacturing a solid-state imaging device in which at least a flattening layer, a color filter layer, and a substantially hemispherical microlens are sequentially arranged as constituent elements on a plurality of photoelectric conversion elements.
1) a step of forming a flattening layer having an infrared absorbing function on a photoelectric conversion element of a semiconductor substrate by using a resin coating solution having an infrared absorbing function;
2) a step of forming a color filter layer of a plurality of colors by photolithography on the flattening layer using a photosensitive colored resist using a coloring material as a coloring material;
3) forming an infrared absorbing layer on the color filter layers of the plurality of colors using a resin coating solution having an infrared absorbing function;
4) using an alkali-soluble, photosensitive, and heat-flowable lens material on the infrared absorption layer to form a lens matrix by photolithography and heat treatment;
5) a step of performing dry etching on the lens matrix, transferring the lens matrix pattern to the infrared absorbing layer, and forming the infrared absorbing layer into a substantially hemispherical microlens having an infrared absorbing function;
A method for manufacturing a solid-state imaging device, comprising:
[0015]
Further, the present invention provides the method for manufacturing a solid-state imaging device according to the present invention, wherein, 3) forming an infrared absorbing layer on the color filter layers of the plurality of colors by using a resin coating liquid having an infrared absorbing function; 4) using an alkali-soluble, photosensitive, and heat-flowable lens material on the infrared-absorbing layer, and applying an ultraviolet-absorbing layer between the step of forming a lens matrix by photolithography and heat treatment. A method of manufacturing a solid-state imaging device, comprising a step of forming a solid-state imaging device.
[0016]
Also, the present invention provides the method for manufacturing a solid-state imaging device according to the above invention, wherein the resin coating liquid is a resin coating liquid containing a plurality of infrared absorbers having different infrared absorption wavelength ranges. This is a method for manufacturing an element.
[0017]
Further, the present invention provides the method for manufacturing a solid-state imaging device according to the above invention, wherein the 5) dry etching is performed on the lens matrix, a lens matrix pattern is transferred to an infrared absorption layer, and the infrared absorption layer is subjected to infrared absorption. A method for manufacturing a solid-state imaging device, characterized in that in a process of forming a substantially hemispherical microlens having a function, transfer of a lens matrix pattern is performed halfway in a thickness direction of a color filter layer.
[0018]
Further, the present invention provides the method for manufacturing a solid-state imaging device according to the above invention, wherein the 5) dry etching is performed on the lens matrix, a lens matrix pattern is transferred to an infrared absorption layer, and the infrared absorption layer is subjected to infrared absorption. A method of manufacturing a solid-state imaging device, characterized by adding a step of coating and laminating a thin film of an infrared absorbing layer after a step of forming a substantially hemispherical microlens having a function.
[0019]
Further, the present invention is the method for manufacturing a solid-state imaging device according to the above invention, further comprising a step of laminating a thin film of a low refractive index resin on the outermost layer of the microlens. .
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a solid-state imaging device according to the present invention will be described based on its embodiments.
FIG. 9 is a sectional view showing one embodiment of the solid-state imaging device according to the present invention. As shown in FIG. 9, the solid-state imaging device according to the present invention has a flat surface having an infrared absorption function on a semiconductor substrate (31) having a photoelectric conversion element (32), a light shielding layer (30), etc. formed on the surface thereof. A layer (34), a color filter layer (33), and a substantially hemispherical microlens (39) having an infrared absorbing function are sequentially formed.
As shown in FIG. 9, in one embodiment of this solid-state imaging device, the substantially hemispherical microlens (39) and the flattening layer (34) among the components have an infrared absorbing function. This is a solid-state imaging device that does not require a conventional infrared cut filter without deteriorating color reproducibility.
[0021]
Further, the solid-state imaging device according to the present invention is a solid-state imaging device in which an ultraviolet absorbing layer is provided between the flattening layer and the color filter layer.
In recent years, the miniaturization of solid-state imaging devices has progressed, and pixels (or microlenses) are becoming extremely fine regions with a pitch of 3 μm or less or a pitch of 2 μm or less. In these fine pixels, the fluctuation of the pattern shape has a bad influence on the image quality such as unevenness.
In order to prevent halation in a stepper exposure apparatus (ultraviolet light having an exposure wavelength of 365 nm), which causes pattern pattern fluctuation, it is desirable to form an ultraviolet absorbing layer as a base of the color filter layer in advance.
[0022]
Further, the method for manufacturing a solid-state imaging device according to the present invention is characterized in that a step of forming an ultraviolet absorbing layer by coating is inserted between the step of forming an infrared absorbing layer and the step of forming a lens matrix. By providing an ultraviolet absorbing layer, halation in a stepper exposure apparatus can be prevented, and a high-precision microlens pattern can be formed. Further, a function of protecting the infrared absorbing layer having relatively low light resistance from ultraviolet light can be provided.
[0023]
For the ultraviolet absorbing layer, a transparent resin such as an acrylic resin, an epoxy resin, a polyester resin, a urethane resin, a melamine resin, a urea resin, a styrene resin, a phenol resin, or a copolymer thereof can be used.
The ultraviolet rays include an i-line (365 nm) used in the manufacturing process of the solid-state imaging device and ultraviolet light included in external light when using a camera equipped with the solid-state imaging device. With respect to the former, the ultraviolet absorbing layer prevents the halation of the i-line (365 nm) and secures the pattern shape of the lens matrix. The latter is absorbed to prevent functional deterioration of the infrared absorbing layer.
[0024]
The ultraviolet absorbing function can be achieved by adding an ultraviolet absorbing compound or an ultraviolet absorbing agent to the transparent resin or by a pendant (incorporating a reactive ultraviolet absorbing agent into a resin molecular chain).
Examples of the ultraviolet absorber usable in the present invention include benzotriazole-based compounds, benzophenone-based compounds, salicylic acid-based compounds, coumarin-based compounds, and the like. Among these ultraviolet absorbers, for example, light stabilization such as hinderedamine-based compounds An agent or a quencher (for example, a singlet oxygen quencher) may be added.
Further, an ultraviolet absorber of fine metal oxide particles such as cerium oxide and titanium oxide can also be used.
[0025]
Examples of the infrared absorber usable in the present invention include anthraquinone compounds, phthalocyanine compounds, cyanine compounds, polymethylene compounds, aluminum compounds, diimonium compounds, immonium compounds, and azo compounds.
The infrared absorbing function can be achieved by adding an infrared absorbing compound or an infrared absorbing agent to the transparent resin or by pendant (incorporating a reactive dye such as a reactive dye into a resin molecular chain in the form of a reactive infrared absorbing agent). .
[0026]
Most of the infrared absorbers have a limited absorption wavelength range, and all the regions in the near-infrared region and the infrared region (for example, 650 nm to 1100 nm) required for a photoelectric conversion element such as a C-MOS or a CCD are a single type of infrared light. It is difficult to cover with an absorbent. Therefore, it is preferable to use a mixture of a plurality of infrared absorbers of about 2 to 6 kinds or to use one constituent element in a multilayer.
[0027]
In order to provide a sufficient infrared absorption function while securing the transmittance in the visible region (400 nm to 700 nm), a plurality of components provided on a photoelectric conversion element such as a C-MOS or a CCD need to have an infrared absorption function. Is preferably shared.
For example, the same infrared absorbing agent is contained in different components to enhance the infrared absorbing function, or the infrared absorbing agents having different absorption wavelength ranges are included in different components to share the infrared absorbing function. Is preferred.
In addition, it is also possible to select which component to include in consideration of the heat resistance and the like of the infrared absorber.
[0028]
Further, in the primary color (RGB) -based or complementary color (YMC) -based color filter layers provided on the photoelectric conversion element, the spectral characteristics (absorption) in the infrared region are different for each color. In the case of having an infrared absorbing agent, it is preferable that the absorbing agent has a different absorption wavelength range, that is, the type and content of the infrared absorbing agent are adjusted.
[0029]
In the present invention, it is basically preferable to make dry etching as deep as possible in order to reduce the distance under the lens. However, when the color filter layer is placed under the ground, the flat surface (effective surface) of the color filter layer becomes small, and the amount of incident light with reduced color purity from around the microlens increases, which leads to deterioration of image quality.
Therefore, it is more preferable that the depth of the dry etching is halfway in the thickness direction of the color filter layer.
[0030]
Further, in the present invention, as a material used for forming the color filter layers of a plurality of colors, a coloring resin using an organic pigment as a coloring material may be employed. However, in the case of organic pigments, there is a difference in the etching rate in dry etching depending on the type thereof, the shape of the microlens is easily changed for each color, and the surface shape is rough, and in addition, the present invention is intended for In a solid-state imaging device with a fine pixel pitch, the particle size (particles) of the pigment itself tends to have a bad effect on the S / N ratio, and the filtration of the material (removal of foreign substances) is difficult, so that the dye is colored. It is more preferable that the material is a colored resin.
[0031]
In the present invention, a thin film of an infrared absorbing layer may be laminated on the microlens by coating in order to reduce the non-opening and increase the aperture ratio of the microlens or to improve the infrared absorbing function.
Further, in the present invention, in order to reduce the re-reflection of incident light from the surface of the microlens and the non-opening, a thin film of a low refractive index resin is further formed on the microlens or the thin film of the infrared absorption layer. It is desirable to form.
In addition, the lower layer exposed between the microlenses absorbs stray light reflected on the surface of the microlens and reduces noise (in this case, re-incident reflected light) generated in the solid-state imaging device to some extent. Alternatively, a thin film of a material having a low refractive index may be laminated.
[0032]
【Example】
Hereinafter, a method for manufacturing a solid-state imaging device according to the present invention will be described in detail with reference to examples.
<Example 1>
As shown in FIG. 1, after a flattening layer (34) is formed on a semiconductor substrate (31) on which a photoelectric conversion element (32) and a light shielding layer (30) are formed, R (red), G (green), Using three color resists of B (blue), color filter layers (33) of three colors were sequentially formed by known photolithography using a stepper exposure apparatus. The thickness of each color filter layer (33) was 0.9 μm to 0.8 μm.
[0033]
For R (red), G (green), and B (blue) of the color filter layer (33), a color resist manufactured by Toyo Ink Mfg. Co., Ltd. using an organic pigment as a coloring material was used. The color arrangement of this embodiment is a so-called Bayer arrangement in which one pixel is composed of a total of four elements of two G (green), one R (red), and one B (blue). FIG. 4A is a plan view from the microlens side of an example of the solid-state imaging device, and also shows a two-dimensional (planar) arrangement of the color filter layers and the microlenses in the Bayer arrangement. .
[0034]
Next, as shown in FIG. 2, an infrared absorbing layer (35) having a thickness of 1 μm was formed on the color filter layer (33) using a resin coating solution containing three types of infrared absorbing agents. Further, a photosensitive phenol resin having a heat flow property was applied by spin coating, exposed, developed, and heat-flowed to obtain a hemispherical lens matrix (20).
The temperature of the heat flow was 200 ° C., and the thickness (lens height) of the lens matrix was 0.7 μm.
As a resin coating liquid having an infrared absorbing function, 100 parts by weight of a thermosetting acrylic resin and three types of infrared absorbers YKR3080, YKR3030, and YKR200 manufactured by Yamamoto Kasei Co., Ltd. were combined and 20 parts by weight of an organic solvent such as cyclohexanone. Was used.
[0035]
Next, as shown in FIG. 3, the semiconductor substrate (31) on which the lens matrix (20) was formed was subjected to an etching process (white arrow) using an O ₂ gas in a dry etching apparatus. The substrate was processed under the conditions of normal temperature, pressure of 1 Pa, RF power of 500 W, and bias of 50 W, and the lens matrix was completely transferred to the infrared absorption layer below to obtain a microlens (39).
It is to be noted that a resin material having a different etching rate such as a resin having a low etching rate such as a phenolic resin is used as a material of the lens matrix (or a material having a high etching rate of a resin of a lower infrared absorption layer). This makes it possible to adjust the shape of the microlens to optimal optical characteristics.
[0036]
<Example 2>
FIG. 7 is a cross-sectional view of the solid-state imaging device according to the second embodiment. On the semiconductor substrate (71) on which the photoelectric conversion element (72) is formed, a flattening layer (74) having an infrared absorption function is applied with an average thickness of 0.6 μm and an ultraviolet absorption layer (70) is applied with a thickness of 0.5 μm. And a color filter layer (73) of three colors using a coloring material of a reactive dye (FIG. 7 is a Bayer arrangement, that is, G (B) because of the cross section taken along the line BB in FIG. 4A). (Green) only pixels are displayed) with a thickness of 0.9 μm.
[0037]
On the color filter layer (73), a thin film of an infrared absorbing layer (76) and a thin film of a low refractive index resin (77) are further formed with a thickness of about 0.1 μm.
These thin films are formed by spin coating, but the thin film of the infrared absorbing layer is slightly thicker at about 0.5 μm in the concave portion between the microlenses (75). This is an effect that a recess having a depth of about 0.4 μm is formed in advance between colors of the color filter layer by dry etching, as described later.
[0038]
First, as shown in FIG. 5, a planarizing layer (74) having an infrared absorbing function and an ultraviolet absorbing layer (70) were both formed on a semiconductor substrate (71) by coating using a spin coating method. The hardening of these layers was performed on a hot plate at 230 ° C. Further, color filter layers (73) of three colors were sequentially formed by the same photolithography as in Example 1 using a color resist (acrylic photosensitive resin base) using a dye as a coloring material.
After forming the infrared absorbing layer and the lens matrix in the same manner as in Example 1, the lens matrix was transferred by dry etching to form a microlens (75). In this case, etching was performed to a part of the color filter layer (73). A recess having a depth of about 0.4 μm was formed between pixels of the color filter layer (73).
[0039]
Next, as shown in FIG. 6, a thin film (76) of the infrared absorbing layer was formed to a thickness of about 0.1 μm (the recesses between the microlenses became thicker).
Next, as shown in FIG. 7, a low-refractive-index resin (fluorine-based acrylic resin, refractive index 1.45) (77) was formed to a thickness of about 0.1 μm by coating. The lamination of the low-refractive-index resin (77) reduces the light reflectance by approximately 2% (light-transmittance) as compared with a configuration without the low-refractive-index resin (77) (for example, the configuration in FIG. 6). Increased by 2%).
[0040]
【The invention's effect】
According to the present invention, since the microlens and the flattening layer, which are components of the solid-state imaging device, have an infrared absorbing function, the conventional infrared cut filter is unnecessary, and the camera can be easily reduced in size.
[0041]
The present invention also includes a step of forming a flattening layer having an infrared absorbing function on a photoelectric conversion element of a semiconductor substrate, a step of forming a color filter layer, a step of forming an infrared absorbing layer, Forming a mold, performing dry etching, transferring the lens matrix pattern to the infrared absorbing layer, and forming the infrared absorbing layer into a microlens having an infrared absorbing function. In addition, the present invention provides a method for manufacturing a solid-state imaging device in which a microlens and a flattening layer, which are components of the solid-state imaging device, have an infrared absorption function and do not require a conventional infrared cut filter.
[0042]
Further, according to the present invention, a plurality of infrared absorbers having different infrared absorption wavelength ranges are divided into respective constituent elements to provide an absorption performance, so that the solid-state imaging device can easily set a wide range of infrared absorption function without difficulty. In addition, due to the heat resistance and light resistance of each infrared absorber, there is a merit that it can be disposed at an optimum location.
Further, according to the present invention, since the lens matrix is transferred to the infrared absorption layer using dry etching, an imaging element having a thin film configuration with high light use efficiency can be provided. Further, since etching is performed on a part of the color filter, the thickness can be further reduced, and a solid-state imaging device with higher image quality can be provided.
[0043]
In addition, the present invention can provide an effect of protecting an infrared absorbing agent having slightly poor light resistance by imparting an ultraviolet absorbing function to the surface of the microlens or the base of the color filter. Further, by forming a thin film of a low refractive index resin on the surface of the microlens and the non-opening portion, reflected light can be reduced, and the image quality of the solid-state imaging device is improved. Also, the reflected light from the microlens or the surface of the thin film of the infrared absorbing layer becomes re-reflected light from the cover glass of the solid-state image sensor and re-enters the solid-state image sensor, causing noise and deteriorating image quality. The solid-state imaging device of the present invention can reduce such noise, and thus can obtain high image quality.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a method for manufacturing a solid-state imaging device according to the present invention.
FIG. 2 is an explanatory diagram of a method for manufacturing a solid-state imaging device according to the present invention.
FIG. 3 is an explanatory diagram of a method for manufacturing a solid-state imaging device according to the present invention.
FIG. 4A is a plan view of another example of the solid-state imaging device as viewed from the microlens side. FIG. 4B is a cross-sectional view taken along line BB in FIG.
FIG. 5 is an explanatory diagram of the method for manufacturing the solid-state imaging device according to the second embodiment.
FIG. 6 is an explanatory diagram of the method for manufacturing the solid-state imaging device according to the second embodiment.
FIG. 7 is a sectional view of a solid-state imaging device according to a second embodiment.
FIG. 8 is a sectional view of an example of a solid-state imaging device according to a known technique.
FIG. 9 is a sectional view showing one embodiment of a solid-state imaging device according to the present invention.
[Explanation of symbols]
20 ... Lens matrix 30 ... Light shielding layers 31, 71 ... Semiconductor substrates 32, 52, 72, 82 ... Photoelectric conversion elements 33, 73, 83 ... Color filter layers 34, 74, 84 85 flattening layers 35, 70 infrared absorbing layers 39, 55, 75, 89 microlenses 49 non-opening 76 thin film of infrared absorbing layer 77 low Refractive index resin 78: Distance under lens

Claims (8)

In a solid-state imaging device in which at least a flattening layer, a color filter layer, and a substantially hemispherical microlens are sequentially arranged as constituent elements on a plurality of photoelectric conversion elements, the substantially hemispherical microlens and the flattening layer are provided. A solid-state imaging device characterized by having an infrared absorption function. The solid-state imaging device according to claim 1, wherein an ultraviolet absorbing layer is provided between the flattening layer and the color filter layer. On a plurality of photoelectric conversion elements, at least a flattening layer, a color filter layer, a substantially hemispherical microlens is sequentially arranged as a component in a method for manufacturing a solid-state imaging device,
1) a step of forming a flattening layer having an infrared absorbing function on a photoelectric conversion element of a semiconductor substrate by using a resin coating solution having an infrared absorbing function;
2) a step of forming a color filter layer of a plurality of colors by photolithography on the flattening layer using a photosensitive colored resist using a coloring material as a coloring material;
3) forming an infrared absorbing layer on the color filter layers of the plurality of colors using a resin coating solution having an infrared absorbing function;
4) using an alkali-soluble, photosensitive, and heat-flowable lens material on the infrared absorption layer to form a lens matrix by photolithography and heat treatment;
5) a step of performing dry etching on the lens matrix, transferring the lens matrix pattern to the infrared absorbing layer, and forming the infrared absorbing layer into a substantially hemispherical microlens having an infrared absorbing function;
A method for manufacturing a solid-state imaging device, comprising: 3) a step of forming an infrared absorbing layer on the color filter layers of the plurality of colors using a resin coating solution having an infrared absorbing function; and 4) an alkali-soluble, photosensitive, and 4. The solid according to claim 3, wherein a step of forming an ultraviolet absorbing layer by coating is inserted between the step of forming a lens matrix by photolithography and heat treatment using a lens material having a heat flow property. A method for manufacturing an image sensor. The method according to claim 3, wherein the resin coating liquid is a resin coating liquid containing a plurality of infrared absorbers having different infrared absorption wavelength ranges. 5) In the step of performing dry etching on the lens matrix, transferring the lens matrix pattern to the infrared absorbing layer, and forming the infrared absorbing layer into a substantially hemispherical microlens having an infrared absorbing function, 6. The method for manufacturing a solid-state imaging device according to claim 3, wherein the transfer of the pattern is performed halfway in the thickness direction of the color filter layer. 5) Dry etching is performed on the lens matrix, a lens matrix pattern is transferred to an infrared absorbing layer, and the infrared absorbing layer is converted into a substantially hemispherical microlens having an infrared absorbing function. 7. The method for manufacturing a solid-state imaging device according to claim 3, further comprising a step of laminating layers by coating. 8. The solid-state imaging device according to claim 3, wherein a step of laminating a thin film of a low refractive index resin is added to the outermost layer of the microlens. Manufacturing method.

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