JP2007053153A - Solid imaging element and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging element with a simple structure free from deposition of dust/foreign matters and free from noise, and also to provide its manufacturing method. <P>SOLUTION: A flat layer 19 having a roughened surface on a microlens and a shading film is formed on a solid imaging element including a photoelectric conversion element 10, a multicolor filter 14, and the microlens 18 laminated in an effective screen, and including the shading film 17 provided outside the effective screen. The flat layer is formed of fluorine-based acrylic resin. Light transmittance in a visible region of 400-600 nm of the shading film is 10% or less. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image sensor having a light receiving element typified by a CMOS or CCD, and a microlens formed on the image sensor, and in particular, there is no defect due to dust and foreign matter adhesion on the surface of the microlens and no noise. The present invention relates to an image sensor and a manufacturing method thereof.

  A region (opening as a photodiode) that contributes to photoelectric conversion of a light receiving element such as a CMOS is limited to about 20 to 40% of the pixel area converted from the pixel pitch, although it depends on the element size and the number of pixels. It will be. A small aperture leads to a decrease in sensitivity as it is, and therefore it is general to form a microlens for condensing in order to compensate for this.

In an image pickup element having a light receiving element such as a CMOS or a CCD, pixel miniaturization is progressing with an increase in the number of pixels. The pixel pitch is in the direction of progressing to miniaturization of 3 μm to 2 μm or less, and the number of pixels is also progressing to increase to 3 million pixels or 5 million pixels even in cameras for mobile phones. Similarly, the microlens disposed on the light receiving element is inevitably miniaturized and multi-pixeled.
The hemispherical microlens is usually made of an organic resin, but its height is in the range of about 2 μm to 0.2 μm. There are the following representative techniques for forming microlenses. The technique disclosed in JP-A-4-226073 is a technique in which an inorganic film such as SiO ₂ is laminated on an organic resin microlens to increase the aperture ratio of the lens.
JP 60-53073 A JP-A-2-244625 JP-A-4-223371 JP-A-4-226073 Japanese Patent Laid-Open No. 6-112659

  An image sensor represented by a light receiving element such as a CMOS or a CCD has a number of pixels (for example, 2 million pixels) of 8 to 12 or 12 inches on a silicon wafer of hundreds to thousands of chips (in the above example, The chip is multifaceted (one chip has 2 million pixels), and after forming color filters and microlenses, it is cut (diced) into individual chips and further modularized.

In such post-processes such as dicing, modularization, and packaging, dust / foreign matter adheres to the microlens, often reducing the yield. In particular, when dust / foreign matter adheres to a swelled portion of a high microlens, the dust / foreign matter is difficult to remove and tends to be a defect in imaging.
In addition, the technology to form an inorganic film so as to cover the color filter and organic resin microlens has problems such as peeling due to the difference in thermal expansion coefficient between the resin and the inorganic film, and rapid heating after moisture absorption of the organic resin part. There were problems with lack of reliability, such as blistering.

  The present invention has been devised in view of the above-described problems, and provides an image pickup device having a simple configuration and avoiding dust / foreign matter adhesion and noise-free, and a method for manufacturing the same.

  In the present invention, a plurality of color filters and microlenses corresponding to each of the photoelectric conversion elements are stacked at least above the photoelectric conversion elements that are two-dimensionally arranged in the effective imaging screen. A solid-state imaging device having a light-shielding film provided outside an effective imaging screen, wherein a flat layer having a roughened surface is formed on the microlens and the light-shielding film.

  The present invention is the solid-state imaging device according to the invention, wherein the flat layer is formed using a fluorine-based acrylic resin.

  The present invention is the solid-state imaging device according to the invention, wherein the light-shielding film has a light transmittance of 10% or less in a visible light region of 400 nm to 600 nm.

  Further, according to the present invention, in the solid-state imaging device according to the above invention, one color of the plurality of color filters is a white (transparent) color filter, and the white (transparent) color filter uses the same material as the microlens. The solid-state imaging device is formed at the same time as the formation of the lens.

In the present invention, a plurality of color filters and microlenses corresponding to each of the photoelectric conversion elements are stacked at least above the photoelectric conversion elements that are two-dimensionally arranged in the effective imaging screen. , In a method of manufacturing a solid-state imaging device in which a light-shielding film is provided outside the effective imaging screen,
1) forming a plurality of color filters, a light shielding film, and a microlens;
2) A step of forming a flat layer on the microlens and the light shielding film,
3) forming a photoresist having a portion corresponding to the pad portion as an opening,
4) removing the photoresist by dry etching to roughen the surface of the flat layer, and removing at least the flat layer and the light-shielding film on the pad portion to expose the pad portion. It is the manufacturing method of the solid-state image sensor characterized.

  According to the present invention, dust / foreign matter adhesion in a post-process such as dicing, which has been a problem with conventional image sensors, is eliminated. Even if dust or foreign matter adheres, it can be removed by simple cleaning. In addition, since the resin surface of the flat layer that has been dry-etched has moisture due to adsorption, electrostatic charge can be suppressed, so that dust and foreign matter can be prevented from adhering due to static electricity. Furthermore, conventionally, it is possible to suppress the reflected light from a microlens or a light shielding film having a high refractive index and a large amount of light reflection, thereby suppressing noise caused by re-reflected light and obtaining a high-quality image.

Hereinafter, embodiments of the present invention will be described in detail.
In the present invention, it is necessary that there is a difference between the refractive index of the microlens and the refractive index of the flat layer. In order to focus light on a photoelectric conversion element (photodiode) below the flat layer, when the microlens is concave, the refractive index of the lens material needs to be lower than the refractive index of the flat layer. When the microlens is convex, the refractive index of the lens material needs to be higher than that of the flat layer.

The material used for the microlens and the flat layer in the present invention is transparent and can be selected from either an inorganic material or a resin material as long as there is a difference in refractive index for condensing. For example, SiO ₂ (silicon dioxide) or SiNx (silicon nitride) is further formed on the semiconductor substrate on which the photoelectric conversion element (light receiving element) is formed by a technique such as CVD, and this is formed into a lens shape by a technique such as dry etching. It is possible to use a microlens that has been processed. Examples of the resin material include acrylic resin, epoxy resin, polyester resin, urethane resin, melamine resin, urea resin, styrene resin, phenol resin, polyimide resin, polyamide resin, and copolymers thereof.

  The material used for the flat layer is preferably a material that can be applied by wet coating such as spin coating when formed on a microlens. For example, an acrylic resin or a fluorine-based acrylic resin coating solution having a flattening effect, for example, having an average molecular weight in the range of 5000 to 10,000 is more preferable. Further, a silicon group or a fluorine group may be introduced for lowering the refractive index. A hybrid (Si and C) resin containing a silicon group may be used. An acrylic resin into which a fluorine group has been introduced is more preferred because the fluorine group is present on the surface of the resin and has the effect of reducing the adhesion of dust and foreign matters such as oils and fats (repelling dirt).

  As a method for roughening the surface of a flat layer made of resin, etc., a method of roughening the resin surface by applying energy such as heat treatment, electron beam or ultraviolet irradiation, or roughing the surface by hitting the surface with plasma or mechanically Any method may be used. By roughening the surface, moisture is adsorbed on the roughened surface, and an antistatic effect, that is, adsorption of dust and foreign matters due to static electricity can be reduced. For this surface roughening, it is extremely effective to use an oxidation treatment with oxygen or a chlorofluorocarbon gas. Moisture adsorption can be further promoted on the oxidized resin surface through hydrates. Dry etching with oxygen or a chlorofluorocarbon gas is suitable for surface roughening. The reason for this will be described in detail in the examples described later.

  From the viewpoint of the resin material, in order to obtain a roughened surface, it is better to have a polymer skeleton with many linear portions. From the viewpoint of the heat resistance of the resin, a polymer containing a large amount of benzene rings is preferable. However, in dry etching and other processes that roughen the surface, a resin / polymer with a large number of straight-chain parts is easier to move, It is easy to obtain a rough surface or a porous surface. In selecting an actual polymer or resin, consideration is given to the difficulty of adhering dust and foreign matter, heat resistance, and a reflectance factor described later.

The difference in refractive index between the material used for the microlens and the material used for the flat layer (the flat layer is preferably a transparent organic resin as described above) is preferably large in order to obtain a light collecting effect. From this point of view, the material used for the microlens is preferably an inorganic material such as silicon nitride (SiN _x ) that can be easily formed by CVD, and an organic material such as phenol resin, polystyrene resin, and high refractive index acrylic resin. Polyimide resin is preferable. These resin skeletons may be introduced with a halogen group, sulfur group or the like introduced to increase the refractive index.

  The difference in refractive index between the microlens and the flat layer laminated on the microlens is preferably 0.1 or more. Taking a large difference in refractive index in combination with an existing transparent material or organic resin can increase the light collection effect and the degree of freedom in microlens manufacturing design. Generally, phenolic and polystyrene resins having photosensitivity, alkali developability, and heat reflow are used as materials for the microlens or lens matrix.

  The most common method is to form a pattern having a rectangular cross-sectional shape by a known photolithography technique and heat-treat the pattern to form a hemispherical cross-sectional shape by thermal reflow (melting). At the time of thermal reflow, it is simultaneously required to reduce the gap (gap) between adjacent microlenses and to have a hemispherical lens with a good cross-sectional shape.

However, in the thermal reflow method, it is relatively difficult to form a lens that is too thin and a lens that is too thick. A lens that is too thin, for example, a microlens having an aspect ratio expressed below of 0.14 or less and a thickness of 2 μm and a thickness of less than 0.3 μm is difficult to be hemispherical and has a trapezoidal cross-sectional shape. Prone.
In addition, a lens that is too thick, for example, a lens having an aspect ratio of 0.4 or more, is likely to be thickened during thermal reflow, and it is difficult to form a microlens with a narrow gap of about 0.3 μm. Adjacent microlenses are fused and become defective.
Aspect ratio = microlens height / macrolens diameter.

  Moreover, if the refractive index resin difference between the refractive index of the lens and the flat layer laminated thereon is small, an extremely thick lens is required to secure the necessary focal distance to the light receiving element, which is not practical. . Therefore, in order to set the thickness of the microlens to a thickness that is not too practical, the difference between the refractive index of the lens material and the refractive index of the flat layer laminated thereon is 0.1 or more, preferably 0. It is desirable to make it 15 or more.

Further, although the refractive index of the flat layer that can be employed in the present invention is not limited, since it is located on the outermost surface of the image sensor, a lower refractive index is better in order to reduce reflected light from the surface. The reflected light is re-reflected by the cover glass of the image sensor module or the imaging lens and re-enters the light receiving section, which causes noise.
The roughening of the surface of the flat layer according to the present invention contributes to the reduction of the adhesion of dust particles and at the same time the effect of reducing the reflected light by roughening the surface to irregularities of about λ / 4 wavelength at the light wavelength level. It can also be obtained.

  In the present invention, a resin layer to which a dye having an infrared absorbing function or an ultraviolet absorbing function (such as an organic pigment or a dye) is added may be provided. Anthracenes and quinones may be pendant to a monomer or polymer, or may be incorporated at the time of polymer polymerization in order to impart an ultraviolet absorbing function.

  Infrared absorbing functions include fine particles of metal oxides such as indium oxide, tin oxide, antimony oxide, zirconia, and ceria, as well as phthalocyanine organic pigments such as cyan pigments, all of which are in the form of fine particles. It is applicable to the present invention. Examples of dye-based infrared absorbers include anthraquinone compounds, phthalocyanine compounds, cyanine compounds, polymethylene compounds, azo compounds, diimonium compounds, and imonium compounds, and these can be applied.

  Metal oxide fine particles such as cerium oxide and titanium oxide may be used as those having an ultraviolet absorbing function. Examples include benzotriazole-based, benzophenone-based, triazine-based, salicylate-based, coumarin-based, xanthene-based, or methoxycinnamic acid-based organic compounds, and these materials may be added or may be pendant to a polymer.

The light-shielding film in the present invention first cuts light in the range of about visible light including the ultraviolet region in the vicinity of about 350 nm to 600 nm, and prevents the light from entering the light receiving element of the semiconductor device as stray light and causing noise. It is righteousness. Therefore, the light transmittance from 400 nm to 600 nm is set to 10% or less.
Although it is possible to use one color of a plurality of colors, for example, blue (Blue) also as a light shielding film, it is preferable to cut the wavelength of the light.

In addition, as a means for forming the light shielding film, there is a photolithography method in which pattern exposure and development are performed. For pattern exposure, a stepper exposure apparatus is often used, but light having a wavelength of 364 nm is often used for stepper exposure. Therefore, if the light shielding film does not transmit light having a wavelength of 364 nm, pattern formation cannot be performed even if pattern exposure is performed. Therefore, the light transmittance of the light shielding film with a wavelength of 364 nm is preferably 1% or more.

In general, an infrared cut filter that is frequently used uses a filter that gradually absorbs light from around 550 nm and cuts a long wavelength after 700 nm. As the absorption region of the film, a range of approximately visible light including the ultraviolet region in the vicinity of approximately 350 nm to 600 nm is sufficient.
In addition, when the infrared cut filter is not used in an external form of the imaging element module, it is preferable to cut the light including light having a long wavelength of 600 nm or longer.

However, the light-shielding film obtained by mixing a plurality of organic pigments, or the light-shielding film using carbon or graphite that imparts infrared absorptivity as a pigment, and the surface reflectivity thereof are considerably large at about 6 to 7%. The main purpose of the flat layer according to the present invention is to prevent dust from adhering to the dicing process in the post-process. However, the flat layer is also formed flat on the light shielding film formed outside the effective screen of the image sensor. The reflectance from the layer interface is extremely small. For example, the reflectance from the interface can be 0.5% or less.
Further, by using a material having a low refractive index for the flat layer, and by devising roughening of the surface of the flat layer, reflection from the flat layer surface can be suppressed.

For roughening to suppress reflection from the flat layer surface, for example, the flat layer surface is dry-etched in an oxygen plasma atmosphere. Depending on the amount of the curing agent of the flat layer, it shows a texture in which columnar resin protrusions with a height of 0.1 μm or columnar resins with a height of 0.03 to 0.3 nm are arranged, or a surface appearance of fine irregularities. .
Such a surface appearance can be adjusted by the kind and amount of the resin and the curing agent, the coating film thickness, the film hardening condition, the dry etching condition, and the like.

  The columnar resin formed by dry etching preferably has a size and a pitch of about λ / 4 of the wavelength of light in order to increase the antireflection curing of light. Even if the size and pitch are not exactly λ / 4, the apparent refractive index of the surface of the flat layer is lowered by the gap between the columnar resins, so that it has a function of suppressing reflection.

The following examples illustrate the invention in detail.
In the first embodiment, an image sensor having four color filters of cyan, yellow, magenta, and black is formed. In the second embodiment, four color filters of white (transparent), yellow, red, and black are formed. However, the present invention may be applied to an image sensor having a three-color configuration of green, blue, and red as shown in FIG.
Further, although the light shielding film is shown as a black single color configuration different from the above black or black, a configuration in which a plurality of colors used for a color filter are superimposed may be used. The light-shielding film may be a single blue color in an image sensor having a three-color configuration of green, blue, and red.

Further, in the following examples, the flat layer is exemplified only by the fluorine-based acrylic resin, but substantially the same effect can be obtained even if it is formed by a highly heat-resistant acrylic resin or the like.
In addition, in the fluorine-based acrylic resin and the high heat-resistant acrylic resin, since the refractive index of the latter resin material is high, the material used for the microlens has a higher refractive index (for example, silicon nitride having a refractive index of 2.1). ).

As shown in FIG. 1, the solid-state imaging device of the present embodiment has an ultraviolet absorption film 13, a color filter 14, a light shielding film 17, a microlens 18, and a semiconductor substrate 11 having a photoelectric conversion element 10.
A flat layer 19 is laminated.
The ultraviolet absorbing film 13 is used to form the color filter 14 with good pattern accuracy and shape in the photolithography process, and is applied and formed before forming the color filter. The ultraviolet absorbing film 13 is a material in which an ultraviolet absorbing function is incorporated into the transparent resin as described above, and is formed with a film thickness of, for example, 0.06 nm.

The color filter 14 uses a color resist (acrylic photosensitive resin) in which organic pigments of cyan C, yellow Y, magenta M, and black Bl are dispersed, and performs processes such as coating, drying, exposure, development, and hardening. After that, it was formed with a film thickness of about 1 μm.
Black is a so-called infrared transmission filter that transmits light having a long wavelength in the near-infrared region of about 700 nm or more with a transmittance of 10% or less in the light wavelength range of 400 nm to 600 nm. That is, an arithmetic process is performed to subtract the black output value from the respective integrated values (output values of the photoelectric conversion elements) of cyan, yellow, and magenta obtained by the light receiving elements that have received the light that has passed through each color filter. This is a filter for performing correction, particularly infrared correction for the above three colors.

  Further, the black color resist may be used as a material for forming the light shielding film 17. The light shielding film 17 was formed to a thickness of 1 μm. The black organic pigment is composed of a plurality of organic pigments such as cyan and red.

  The microlens 18 is made of a thermosetting acrylic resin (refractive index of 1.58) containing 5% of a UV absorber. The acrylic resin contains a UV absorber to increase the refractive index, and similarly, a benzene ring is introduced into the polymer skeleton in order to increase the refractive index. In Example 1, the addition of the UV absorber to the resin material of the microlens 18 is not an essential condition.

  FIG. 8 shows a schematic plan view of one chip of the image sensor. A planar positional relationship among an effective imaging screen 88 in which a photoelectric conversion element, a color filter, and a microlens are stacked, a light shielding film 89, and an aluminum pad 82 is shown.

  The flat layer 19 is made of a fluorine-based acrylic resin (thermosetting type) having a refractive index of 1.47. As shown in the SEM image of FIG. 3, the surface of the flat layer 19 has irregularities close to λ / 4.

  When the semiconductor substrate on which the solid-state imaging device according to the present example was formed was diced, almost no dust or foreign matter such as dicing dust was observed on the surface of the flat layer 19. Even when dust / foreign matter adhesion was observed, it could be easily removed by washing with pure water guided by ultrasonic waves.

Further, when the reflectance of the flat layer 19 of the present example was measured using an integrating sphere of Murakami Color Co., Ltd., and the total reflectance by diffused light was measured, the reflectance of the surface was about 3%.
The surface reflectance of the flat layer (without surface roughening) made of phenol resin (refractive index of 1.6) used as a normal microlens material was about 6%. In addition, the reflectance measurement did not use the semiconductor substrate of this example, but applied a black paint to a silicon wafer and formed a flat layer thereon. The flat layer 19 was subjected to dry etching described later to roughen the surface.

Below, the manufacturing method of a present Example is demonstrated in detail using FIG.
As shown in FIG. 2A, a semiconductor substrate on which an ultraviolet absorbing film 13 having a thickness of 0.06 μm, a color filter 14 having a thickness of 1 μm, a light shielding film 17 having a thickness of 1 μm, and a macro lens 18 having an ultraviolet absorbing function are formed. 11 was prepared.
As shown in FIG. 2 (2), a flat layer 19 was applied and formed with a film thickness of 1.5 μm by a spin coating method using a fluorine-based acrylic resin liquid.

As shown in FIG. 2 (3), a resist pattern having a thickness of 1.5 μm was formed using a novolak photosensitive resin so as to cover the flat layer and to exclude the aluminum pad 12 portion. In the portion corresponding to the position of the aluminum pad 12, an opening 22 was formed by an exposure / development photolithography process.
The semiconductor substrate shown in FIG. 2 (3) is dry-etched with a dry etching apparatus to expose the surface of the aluminum pad 12, and at the same time, the resist pattern 20 is removed, thereby obtaining the solid-state imaging device shown in FIG. It was. Both dry gas and oxygen gas were used for the dry etching.
A columnar rough surface having a height of approximately 0.1 μm to 0.2 μm shown in FIG. 3 was formed on the surface of the flat layer of this example.

As shown in FIG. 5, the solid-state imaging device of this embodiment is obtained by laminating an ultraviolet absorbing film 53, a color filter, a light shielding film 57, a microlens 58, and a flat layer 59 on a semiconductor substrate 51 having a photoelectric conversion element 50. It is.
As shown in FIG. 6, the color filter includes a yellow color filter 54, a white (transparent) color filter 55, a red color filter 56, and a black color filter (Bl).

  The ultraviolet absorbing film 53 is for forming a color filter with good pattern accuracy and shape in the photolithography process, and is applied and formed before forming the color filter. The ultraviolet absorbing film 53 is a material in which an ultraviolet absorbing function is incorporated into the transparent resin as described above, and is formed with a film thickness of, for example, 0.06 μm.

The color filter is formed with a film thickness of approximately 1 μm through processes such as coating, drying, exposure, development, and hardening using a color resist in which organic pigments of yellow, red, and black are dispersed. . Black is a so-called infrared transmission filter that transmits light of a long wavelength in the near infrared region after about 700 nm with a transmittance of 10% or less in a light wavelength range of 400 nm to 600 nm. This is a filter for performing color correction by performing a subtraction calculation process from the red 'integral value (output value of the photoelectric conversion element).
The black color is composed of a plurality of organic pigments such as violet and yellow.

A black color resist was used as a material for forming the light shielding film 57. The black color resist can obtain a light-shielding film that absorbs and cuts not only visible light but also near-infrared light by dispersing carbon fine particles in a pigment.
The light shielding film 57 was formed with a black color resist to a thickness of 1 μm.

  In this embodiment, the colors of blue, green, and red corresponding to the image sensor are the light receiving elements to which the light that has passed through the white (transparent), yellow ', red', and black color filters is input. Is obtained by performing an arithmetic process of blue = white-yellow ', green = yellow'-red', and red = red'-black.

  When the semiconductor substrate on which the solid-state imaging device according to this example was formed was diced, dust and foreign matter such as dicing trash were hardly observed on the surface of the flat layer 59. Even if dust / foreign matter adhesion was observed, it could be easily cleaned by flowing ultrasonic cleaning water of pure water.

Below, the manufacturing method of a present Example is demonstrated in detail using FIG.
As shown in FIG. 7 (1), an ultraviolet absorbing film 53 having a thickness of 0.06 μm, a yellow color filter 54 having a thickness of 1 μm, a red color filter (not shown), a black color filter (not shown), A semiconductor substrate 51 on which a light-shielding film 57 having a film thickness of 1 μm using carbon as a pigment was prepared.

As shown in FIG. 7 (2), a transfer layer 60 having a film thickness of 1.8 μm is formed on a transfer layer 60 having a film thickness of 1.8 μm by a spin coating method using a fluorine-based acrylic resin liquid, and an etching control layer 61 having a thickness of 1 μm by a phenol-based thermosetting resin. And a lens matrix 62 of the thermal reflow lens were formed by a known thermal flow process technique.
Next, using the lens matrix 62 as a mask, the etching control layer 61 was anisotropically etched by dry etching using a chlorofluorocarbon gas to form the intermediate lens 63 shown in FIG. Adjacent intermediate lenses are in a state of sticking between the lenses of the intermediate lens 63.

  Etching was further performed to copy the shape of the intermediate lens 63 onto the transfer layer 60, whereby a microlens 58 shown in FIG. The resin material of the transfer layer 60 was an acrylic resin containing 5% of a UV absorber as in Example 1.

7 (2), on the semiconductor substrate 51 on which the yellow color filter 54, the red color filter 56 (not shown), the black color filter (black) (not shown), and the light shielding film 57 are formed. The provided transfer layer 60 is formed on the micro lens 58 corresponding to each of the yellow color filter 54, the red color filter 56, and the black color filter (black) by etching in FIG. .
On the other hand, in the case of the white (transparent) color filter 55, the upper half portion of the transfer layer 60 is formed on the microlens 58, and the remaining lower half portion is the white (transparent) color filter 55. That is, the same material as that used for forming the microlens 58 is used, and the white (transparent) color filter 55 is formed simultaneously with the formation of the microlens 58.

The following steps are the same as in Example 1.
As shown in FIG. 7 (5), using a novolac photosensitive resin, a resist pattern 64 having a thickness of 2 μm is covered with a flat layer 59 made of a fluorine-based acrylic resin, and the portion of the aluminum pad 52 is removed. Formed as follows. In the portion corresponding to the position of the aluminum pad 52, an opening 65 was formed by a photolithographic process of exposure and development.

  The semiconductor substrate shown in FIG. 7 (5) is dry-etched by a dry etching apparatus to expose the surface of the aluminum pad 52, and at the same time, the resist pattern 64 is removed, and the solid-state imaging shown in FIG. 7 (6). An element was obtained. Both dry gas and oxygen gas were used for the dry etching.

It is a fragmentary sectional view of Example 1 of the solid-state image sensing device by the present invention. FIG. 6 is a partial cross-sectional view showing a process of the manufacturing method of Example 1. It is a SEM image of the roughened flat layer surface. FIG. 3 is a plan view showing a color filter arrangement of Example 1. It is a fragmentary sectional view of Example 2 of the solid-state image sensing device by the present invention. FIG. 6 is a plan view showing a color filter arrangement of Example 2. 6 is a partial cross-sectional view showing a process of a manufacturing method of Example 2. FIG. It is a schematic plan view of an image sensor 1 chip. It is a top view which shows the color filter arrangement | sequence of green, blue, and red.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 50 ... Photoelectric conversion element 11, 51 ... Semiconductor substrate 12, 52, 82 ... Aluminum pad 13, 53 ... Ultraviolet absorption film 14 ... Color filter 17, 57 of Example 1 , 89..., Light shielding films 18 and 58... Microlenses 19 and 59... Flat layer 20... Resist pattern 22 and 65. (Transparent) Color filter 56 ... Red 'color filter 60 ... Transfer layer 61 ... Etching control layer 63 ... Intermediate lens 64 ... Regist pattern 88 ... Effective imaging screen Bl ... Black color filter

Claims (5)

  At least above the photoelectric conversion elements that are two-dimensionally arranged in the effective imaging screen, a plurality of color filters and microlenses corresponding to each of the photoelectric conversion elements are stacked, and the effective imaging screen A solid-state imaging device provided with a light-shielding film outside, wherein a flat layer having a roughened surface is formed on the microlens and the light-shielding film.   The solid-state imaging device according to claim 1, wherein the flat layer is formed using a fluorine-based acrylic resin.   3. The solid-state imaging device according to claim 1, wherein the light shielding film has a light transmittance of 10% or less in a visible light region of 400 nm to 600 nm.   One color of the plurality of color filters is a white (transparent) color filter, and the white (transparent) color filter is formed of the same material as the microlens and is formed simultaneously with the formation of the microlens. The solid-state imaging device according to claim 1, claim 2, or claim 3. At least above the photoelectric conversion elements that are two-dimensionally arranged in the effective imaging screen, a plurality of color filters and microlenses corresponding to each of the photoelectric conversion elements are stacked, and the effective imaging screen In the manufacturing method of the solid-state imaging device provided with a light shielding film outside,
1) forming a plurality of color filters, a light shielding film, and a microlens;
2) A step of forming a flat layer on the microlens and the light shielding film,
3) forming a photoresist having a portion corresponding to the pad portion as an opening,
4) removing the photoresist by dry etching to roughen the surface of the flat layer, and removing at least the flat layer and the light-shielding film on the pad portion to expose the pad portion. A method for manufacturing a solid-state imaging device.