JP3672663B2 - Solid-state imaging device and manufacturing method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to a solid-state imaging device and a manufacturing method thereof.
[0002]
[Prior art]
  In recent years, the solid-state imaging device has been miniaturized. However, since the area of the light receiving portion of each solid-state imaging element is reduced as the size of the solid-state imaging device is reduced, a decrease in light sensitivity in the solid-state imaging device is a problem. In order to solve this problem, a solid-state imaging device including a microlens that collects light in a light receiving unit has already been realized. Currently, the microlens formation technique is an indispensable technique for manufacturing a solid-state imaging device.
[0003]
  Hereinafter, a conventional solid-state imaging device will be described.
[0004]
  FIG. 8 is a cross-sectional view illustrating the structure of an example of a conventional solid-state imaging device. In FIG. 8, 11 is a semiconductor substrate, 12 is a photodiode portion formed on the surface portion of the semiconductor substrate 11 and converts incident light into electric charges, and 13 is a first for flattening the surface of the semiconductor substrate 11. The flattening layer, 14 is a color filter formed on the first flattening layer 13, 15 is a second flattening layer for flattening the steps of the color filter 14, and 50 is the second flattening layer 15. It is a microlens that is formed on top and collects light on the photodiode portion 12.
[0005]
  The first planarizing layer 13 is formed by applying a transparent film material on the semiconductor substrate 11 to a required thickness.
It is formed by cloth. The color filter 14 is formed by, for example, a photolithography technique so as to correspond to each photodiode portion 12. The second planarization layer 15 is formed by applying a transparent film material to the color filter 14 by a required film thickness.
[0006]
  The microlens 50 is made of a phenol resin or the like, and is formed in a hemispherical shape at a position where it hits above each photodiode portion 12. Further, the height is such that the light hitting the surface of the microlens 50 is efficiently collected in the photodiode portion 12.
[0007]
  The hemispherical shape of the microlens 50 is formed by the following process. First, a lens resist is applied on the second planarizing layer 15. Next, an exposure process is performed using a lens mask, and further a development process is performed, thereby patterning the lens resist at a position above each photodiode portion 12. Further, by performing a heat treatment and dissolving the patterned lens resist, the hemispherical shape of the microlens 50 can be formed using the surface tension.
[0008]
  FIG. 9 is a view of a conventional solid-state imaging device as viewed from above. In FIG. 9, reference numeral 50 denotes a microlens. Further, x is a space at the center of the microlens 50, and y is a space at the end.
[0009]
  FIG. 10 is a cross-sectional view for illustrating the structure of another example of a conventional solid-state imaging device. In FIG. 10, 11 is a semiconductor substrate, 12 is a photodiode portion, 13 is a first planarizing layer, 14 is a color filter, and 15 is a second planarizing layer, which is the same as that shown in FIG. It is. 8 is different from the solid-state imaging device shown in FIG. 8 in that an interlayer insulating film 16 is formed between the semiconductor substrate 11 and the first planarization layer 13. The surface of the interlayer insulating film 16 is smooth, but has unevenness along the unevenness of the semiconductor substrate 11. The first planarization layer 13 is formed to flatten the irregularities on the surface of the interlayer insulating film 16.
[0010]
[Problems to be solved by the invention]
  However, the conventional solid-state imaging device and the manufacturing method thereof have the following problems.
[0011]
  In the solid-state imaging device shown in FIG. 8, in order to further improve the photosensitivity, it is desirable to enlarge the light receiving area of the microlens 50 by reducing the space S between the adjacent microlenses 50 as much as possible.
[0012]
  However, conventionally, when the microlens 50 is formed by heating a patterned lens resist (hereinafter referred to as a lens pattern), the heating temperature is set to a temperature at which the lens pattern is completely dissolved. For this reason, the phenomenon that the melt | dissolved lens pattern protrudes from the bottom face when patterning has arisen.
[0013]
  Therefore, as shown in FIG. 9, the space x at the center of the adjacent microlenses 50 is smaller than the space y at the end. For this reason, even if the space x in the central portion is reduced as much as possible, the space y in the end portion is not reduced as much as possible. Therefore, there is a limit in enlarging the light receiving area of the microlens 50.
[0014]
  In addition, when the space between adjacent lens patterns is too small, the lens patterns protruding by heating and melting come into contact with each other and flow out. For this reason, the shape of the microlens 50 collapses, and the surface area of the hemispherical portion is reduced and the height is also reduced. Therefore, the amount of light collected in the photodiode portion 12 is reduced, and the photosensitivity is lowered.
[0015]
  Further, according to our study, it is known that when the surface area of the light receiving portion is small, the photosensitivity is better when the height of the microlens is higher and the distance between the microlens and the light receiving portion is smaller.
[0016]
  However, according to the prior art, since the lens pattern is completely dissolved, the height H of the microlens 50 cannot be made larger than half the width R of the bottom surface in the light receiving portion arrangement direction due to surface tension. For this reason, when the distance between the microlens 50 and the photodiode portion 12 is small, there is a possibility that the optimal shape of the microlens 50 for collecting light cannot be formed.
[0017]
  When the interlayer insulating film 16 is formed on the semiconductor substrate 11 as in the solid-state imaging device shown in FIG. 10, the distance from the microlens 50 to the photodiode portion 12 is the film thickness of the interlayer insulating film 16. It will be longer by For this reason, even if the shape of the microlens 50 is optimized, the incident light may not be collected in the photodiode portion 12 due to the influence of scattering or the like. In particular, when the refractive index of the interlayer insulating film 16 is higher than the refractive indexes of the first planarizing layer 13 and the color filter 14, such a phenomenon appears remarkably and the photosensitivity is lowered.
[0018]
  In view of the above problems, the present inventionHalfIt is an object of the present invention to suppress a decrease in photosensitivity and obtain high photosensitivity even in a solid-state imaging device in which an interlayer insulating film is formed on a conductor substrate.
[0019]
[Means for Solving the Problems]
  In order to solve the above problems, the present invention,layerThe material of the flattening layer formed on the interlayer insulating film is made to have a higher refractive index than that of the interlayer insulating film, thereby forming a pseudo convex lens that collects light at the light receiving portion. Furthermore, the material of the flattening layer is dissolved in a liquid state by heating, and the flattening layer is formed extremely thin by performing heat treatment in the manufacturing process, thereby reducing the distance from the microlens to the light receiving portion. .
[0020]
  Specifically, Claim 1The solution provided by the present invention is a semiconductor substrate having a light receiving portion for converting incident light into electric charges and having a light receiving portion region formed in a concave shape, and a light receiving portion region formed on the semiconductor substrate and recessed in a concave shape. As a solid-state imaging device comprising a flat insulating layer and a flattening layer formed on the insulating film and flattening the surface of the insulating film, the flattening layer is made of a material having a refractive index higher than that of the insulating film. Formed byIn the concave portion of the insulating film, a pseudo convex lens is formed by the insulating film and the planarizing layer.
[0021]
  Claim 1According to the invention, since the planarizing layer is formed of a material having a higher refractive index than that of the insulating film, a pseudo-convex lens is formed in the light receiving portion region that is recessed in a concave shape. With this pseudo-convex lens, in the conventional solid-state imaging device, the light scattered inside the device and not reaching the light receiving portion can be concentrated on the light receiving portion.
[0022]
  According to a second aspect of the present invention, in the solid-state imaging device according to the first aspect, the insulating film and the planarizing layer include a silicon oxide film and a phenol-based resin film, a fluorine-based resin film and a silicon oxide film, and a fluorine-based resin film. And acrylic resin film, fluorine resin film and phenol resin film, fluorine resin film and polyimide resin film, silicon oxide film and acrylic resin film, silicon oxide film and polyimide resin film, and acrylic resin film And a phenolic resin film.
[0023]
  According to a third aspect of the present invention, in the solid-state imaging device of the first aspect, the material for forming the planarization layer is a material that dissolves in a liquid state by heating.
[0024]
  Claim 3According to the invention,flatSince the carrier layer is formed of a material that dissolves by heating, the planarization layer can be formed extremely thin by heating in the manufacturing process, so the distance from the microlens to the light receiving portion is reduced, and the light incident on the microlens Can be easily collected in the light receiving part.
[0025]
  According to a fourth aspect of the present invention, in the solid-state imaging device according to the third aspect, the insulating film is a fluorine-based resin film, a silicon oxide film, or an acrylic resin film, and the planarizing layer is a phenol-based thermoplastic resin. It shall consist of
[0026]
  Claim 5The solution provided by the invention is that an insulating film is formed on a semiconductor substrate having a light receiving portion and the light receiving portion region is formed in a concave shape, and the surface of the insulating film is flattened on the insulating film. As a method for manufacturing a solid-state imaging device including a planarizing layer forming step for forming a planarizing layer, the planarizing layer forming step includes forming the planarizing layer from a material having a higher refractive index than the insulating film. The process to perform is included.Further, in the insulating film forming step and the flattening layer forming step, the insulating film and the flattening layer are divided into a silicon oxide film and a phenol resin film, a fluorine resin film and a silicon oxide film, a fluorine resin film and an acrylic film. Resin film, fluorine resin film and phenol resin film, fluorine resin film and polyimide resin film, silicon oxide film and acrylic resin film, silicon oxide film and polyimide resin film, and acrylic resin film and phenol It shall be formed by a combination of any one of the system resin films.
[0027]
  Claim 5According to the invention, since the planarizing layer is formed of a material having a higher refractive index than that of the insulating film, a pseudo-convex lens is formed in the light receiving portion region that is recessed in a concave shape. The pseudo-convex lens can concentrate light that has been scattered inside the device and has not reached the light receiving unit in the conventional solid-state imaging device, on the light receiving unit.
[0028]
  Claim 6The solution provided by the invention is that an insulating film is formed on a semiconductor substrate having a light receiving portion and the light receiving portion region is formed in a concave shape, and the surface of the insulating film is flattened on the insulating film. As a method for manufacturing a solid-state imaging device including a planarizing layer forming step for forming a planarizing layer, the planarizing layer forming step has a refractive index higher than that of the insulating film and is heated by heating. It includes a step of forming the surface of the flattening layer by melting the material by heating and dissolving the material by heating.Further, in the insulating film forming step, a fluorine-based resin film, a silicon oxide film, or an acrylic resin film is formed as the insulating film, and the planarizing layer forming process is performed. In the meantime, the planarizing layer is formed of a phenolic thermoplastic resin.
[0029]
  Claim 6According to the invention, the planarizing layer is formed of a material having a refractive index higher than that of the insulating film and dissolved in a liquid state by heating. Therefore, a pseudo-convex lens is formed in the light-receiving part region that is recessed in a concave shape, and the distance from the microlens to the light-receiving part is reduced. it can.
[0030]
DETAILED DESCRIPTION OF THE INVENTION
  (First embodiment)
  FIG. 1 is a diagram illustrating a manufacturing process of a microlens in the method for manufacturing a solid-state imaging device according to the first embodiment of the present invention, and is a cross-sectional view of the solid-state imaging device in each step.
[0031]
  In FIG. 1A, 11 is a semiconductor substrate, 12 is formed on the surface portion of the semiconductor substrate 11, and is a photodiode portion as a light receiving portion that converts incident light into electric charge, and 13 is a flat surface on the semiconductor substrate 11. 14 is a color filter formed on the first planarization layer 13 by, for example, photolithography, and 15 is a second flattening step on the color filter 14. It is a planarization layer. 1B to 1D, the semiconductor substrate 11, the photodiode portion 12, the first planarizing layer 13, and the color filter 14 are omitted.
[0032]
  First, as shown in FIG. 1A, a lens resist 10 a made of a phenolic thermoplastic resin is applied to the surface of the second planarizing layer 15. The lens resist 10a is deformed by heating, and the refractive index is 1.3 or more.
[0033]
  Next, as shown in FIG. 1B, a lens mask 18 is disposed above the lens resist 10a. The lens masks 18 are arranged at a pitch corresponding to the position of the photodiode portion 12.
[0034]
  By performing an exposure process using this lens mask 18 and further performing a development process, a lens pattern 10b is formed as shown in FIG. Further, in order to improve the light transmittance, the lens pattern 10b is irradiated with UV light. As a result, the lens pattern 10b becomes colorless and transparent as the contained photosensitive agent is decomposed.
[0035]
  Subsequently, heat treatment is performed to form a microlens 10c as shown in FIG.
To do. The heating temperature at this time shall be 130-140 degreeC. The lens pattern 10b starts to melt when the heating temperature reaches 120 to 130 ° C, and completely dissolves when the heating temperature reaches 150 to 160 ° C. By setting the heating temperature to 130 to 140 ° C., which is 10 to 20 ° C. lower than the temperature at which it is completely dissolved, the lens pattern 10b does not protrude from the bottom surface when it is patterned. For this reason, adjacent lens patterns do not flow out in contact with each other, and the shape of the formed microlens 10c does not collapse. That is, the microlens 10c having a hemispherical shape and sufficiently high can be reliably formed.
[0036]
  The space S2 between the adjacent microlenses 10c has the same size as the space S1 between the adjacent lens patterns 10b. For this reason, the space S2 of the microlens 10c can be brought close to 0 by making the space S1 of the lens pattern 10b close to 0. That is, the surface area of the microlens 10c can be enlarged.
[0037]
  Thus, by setting the heating temperature at the time of forming the microlens 10c to a temperature at which the lens pattern 10b is not completely dissolved, it is possible to form the microlens 10c that can efficiently collect light on the photodiode portion 12. In addition, by controlling the heating temperature in the range of 130 to 140 ° C., the shape of the microlens 10 c can be controlled.
[0038]
  2 is a top view of the solid-state imaging device manufactured by the manufacturing method shown in FIG. In FIG. 2, 10 is a microlens. X is the size of the space at the center of the microlens 10, and y is the size of the space at the end.
[0039]
  When the heating temperature is set to 130 to 140 ° C., the lens pattern 10b is not completely dissolved, so that the space x at the center and the space y at the end are equal. Therefore, both the space x at the center and the space y at the end can be reduced, so that the light receiving area of the microlens 10 can be increased as compared with the conventional case.
[0040]
  (Second Embodiment)
  FIG. 3 is a schematic diagram of a solid-state imaging device manufacturing method according to the second embodiment of the present invention.
It is a figure which shows the manufacturing process of a kuro lens, and is sectional drawing of the solid-state imaging device in each process.
[0041]
  In FIG. 3A, 11 is a semiconductor substrate, 12 is a photodiode portion, 13 is a first planarizing layer, 14 is a color filter, and 15 is a second planarizing layer, which are shown in FIG. Is the same as 3B to 3D, the semiconductor substrate 11, the photodiode portion 12, the first planarization layer 13, and the color filter 14 are omitted.
[0042]
  The difference between the second embodiment and the first embodiment is that the lens resist 20a is applied thickly.
[0043]
  First, as shown in FIG. 3A, a lens resist 20a made of a thermoplastic resin is applied on the surface of the second planarizing layer 15 to a thickness of 2 to 4 μm.
[0044]
  Next, as shown in FIG. 3B, a lens mask 18 is disposed above the lens resist 20a. The lens masks 18 are arranged at a pitch corresponding to the position of the photodiode portion 12.
[0045]
  By performing an exposure process using this lens mask 18 and further performing a development process, a lens pattern 20b is formed as shown in FIG. Furthermore, in order to improve the light transmittance, the lens pattern 20b is irradiated with UV light. As a result, the lens pattern 20b becomes colorless and transparent as the contained photosensitive agent is decomposed.
[0046]
  Subsequently, heat treatment is performed to form a microlens 20c as shown in FIG. By setting the heating temperature at this time to 130 to 140 ° C. which is 10 to 20 ° C. lower than the temperature at which the lens pattern 20 b is completely dissolved, the lens pattern 20 b does not flow out of the bottom surface when patterned, A microlens 20c having a hemispherical shape and a sufficiently high height is formed.
[0047]
  According to the manufacturing method shown in FIG. 3, when the cell size is small, the height H of the microlens 20c is larger than half R of the width of the bottom surface of the microlens 20c in the light receiving portion arrangement direction. In addition, the shape of the microlens 20c does not collapse due to surface tension. For this reason, a vertically long microlens is formed.
[0048]
  FIG. 4 is a cross-sectional view for illustrating the structure of the solid-state imaging device manufactured by the manufacturing method according to the second embodiment.
[0049]
  In FIG. 4, 11 is a semiconductor substrate, 12 is a photodiode portion, 13 is a first planarization layer, 14 is a color filter, and 15 is a second planarization layer, as shown in FIG. Is the same. Reference numeral 20 denotes a microlens formed on the second planarizing layer. R1 is half the width of the bottom surface of the microlens 20 in the light receiving portion arrangement direction, R2 is half the width of the cell size in the light receiving portion arrangement direction, and H is the height of the microlens 20. The adjacent microlenses 20 are actually provided with a space of 0.1 to 1.5 μm so as not to contact each other.
[0050]
  The shape of the microlens 20 is a vertically long semi-ellipse that can be expressed by a cycloid curve or a parabola, and the height H is larger than half the width R1 of the bottom surface in the light receiving portion arrangement direction. Further, according to the present embodiment, the height H of the microlens 20 can be made larger than half the width R2 of the cell size in the light receiving portion arrangement direction. By forming a vertically long microlens, incident light can be concentrated on the photodiode portion 12 even in a solid-state imaging device having a small distance from the microlens 20 to the photodiode portion 12.
[0051]
  (Third embodiment)
  FIG. 5 is a cross-sectional view showing the structure of a solid-state imaging device according to the third embodiment of the present invention. In FIG. 5, 11 is a semiconductor substrate, 12 is a photodiode portion as a light receiving portion formed on the surface portion of the semiconductor substrate 11, 16 is an interlayer insulating film as an insulating film formed on the semiconductor substrate 11, and 30 is an interlayer. A first flattening layer as a flattening layer for flattening irregularities on the surface of the insulating film 16, 14 is a color filter formed on the first flattening layer 30, and 15 is a step on the surface of the color filter 14. A second flattening layer 50 to be flattened is a microlens formed on the second flattening layer 15.
[0052]
  The first planarizing layer 30 is made of a material having a higher refractive index than that of the interlayer insulating film 16. For example, the interlayer insulating film 16 and the first planarizing layer 30 are respectively a silicon oxide film and a phenol resin film, a fluorine resin film and a silicon oxide film, a fluorine resin film and an acrylic resin film, or a fluorine resin. Resin film and phenol resin film, fluorine resin film and polyimide resin film, silicon oxide film and acrylic resin film, silicon oxide film and polyimide resin film, acrylic resin film and phenol resin film, etc. Form in combination.
[0053]
  The interlayer insulating film 16 has a thickness of about 0.1 to 1.5 μm. The first planarization layer 30 formed on the interlayer insulating film 16 has a higher refractive index than the interlayer insulating film 16, the color filter 14, and the second planarization layer 15.
[0054]
  Since the first planarization layer 30 is formed of a material having a refractive index higher than that of the interlayer insulating film 16, a downward pseudo convex lens 31 is formed in the concave portion of the interlayer insulating film 16. The center of the pseudo convex lens 31 coincides with the center of the photodiode portion 12. The pseudo-convex lens 31 allows light that was not collected in the photodiode unit 12 in the conventional solid-state imaging device to be collected in the photodiode unit 12. Even if the pseudo convex lens 31 is formed, the distance from the microlens 50 to the photodiode portion 12 does not change, so that the light condensing effect by the microlens 50 can be obtained as usual.
[0055]
  Further, the curvature and depth of the pseudo convex lens 31 can be changed by changing the thickness of the interlayer insulating film 16. By optimizing the shape of the microlens 50 and the pseudo-convex lens 31 and the distance from the microlens 50 and the pseudo-convex lens 31 to the photodiode unit 12, the solid-state imaging device having high photosensitivity regardless of the shape of the photodiode unit 12. Can be obtained.
[0056]
  Further, by combining this embodiment with the first or second embodiment, the light sensitivity of the solid-state imaging device can be further improved.
[0057]
  The present invention can be applied not only to a color solid-state imaging device having a color filter but also to a monochrome solid-state imaging device having no color filter.
[0058]
  (Fourth embodiment)
  FIG. 6 is a cross-sectional view showing the structure of a solid-state imaging device according to the fourth embodiment of the present invention. In FIG. 6, 11 is a semiconductor substrate, 12 is a photodiode portion as a light receiving portion formed on the surface portion of the semiconductor substrate 11, 16 is an interlayer insulating film as an insulating film formed on the semiconductor substrate 11, and 32 is an interlayer. A first flattening layer as a flattening layer for flattening irregularities on the surface of the insulating film 16, 14 is a color filter formed on the first flattening layer 32, and 15 is a step on the surface of the color filter 14. A second flattening layer 50 to be flattened is a microlens formed on the second flattening layer 15.
[0059]
  The interlayer insulating film 16 is made of a fluorine resin film, a silicon oxide film, or an acrylic resin film, and has a thickness of about 0.1 to 1.5 μm. The first planarization layer 32 formed on the interlayer insulation film 16 is made of a thermoplastic resin such as phenol, and has a higher refractive index than the interlayer insulation film 16, the color filter 14, and the second planarization layer 15. It has.
[0060]
  Since the first planarizing layer 32 is formed of a material having a higher refractive index than the interlayer insulating film 16, the downward pseudo convex lens 33 is formed in the concave portion of the interlayer insulating film 16. The center of the pseudo convex lens 33 coincides with the center of the photodiode portion 12. The pseudo-convex lens 33 can collect light that has not been collected in the photodiode unit 12 in the conventional solid-state imaging device. In addition, since the first planarization layer 32 has thermoplasticity, when heated, it dissolves in a liquid and can be completely planarized with a very thin film. As a result, the distance from the microlens 50 to the photodiode portion 12 can be reduced, so that the distance from the microlens 50 to the photodiode portion 12 can be optimized and light can be concentrated.
[0061]
  Further, the curvature and depth of the pseudo convex lens 33 can be changed by changing the thickness of the interlayer insulating film 16. By optimizing the shape of the microlens 50 and the pseudo-convex lens 33 and the distance from the microlens 50 and the pseudo-convex lens 33 to the photodiode unit 12, the solid-state imaging device having high photosensitivity regardless of the shape of the photodiode unit 12. Can be obtained.
[0062]
  FIG. 7 is a diagram illustrating a manufacturing process of the first planarization layer in the manufacturing method of the solid-state imaging device according to the present embodiment, and is a cross-sectional view of the solid-state imaging device in each process. As shown in FIG. 7A, it is assumed that the interlayer insulating film 16 has already been formed on the semiconductor substrate 11 on which the photodiode portion 12 is formed on the surface portion.
[0063]
  Next, as shown in FIG. 7B, a first planarizing resist 32 a made of a thermoplastic resin such as phenol is applied on the interlayer insulating film 16. At this time, the flatness of the surface of the first planarizing resist 32a is not good just by coating. Next, as shown in FIG. 7C, the first planarization resist 32a is dissolved in a liquid state by heating to form a first planarization layer 32b. Through such a process, the first planarization layer 32b having a flat surface and a thin film can be formed.
[0064]
  Further, by combining this embodiment with the first or second embodiment, the light sensitivity of the solid-state imaging device can be further improved.
[0065]
  The present invention can be applied not only to a color solid-state imaging device having a color filter but also to a monochrome solid-state imaging device having no color filter.
[0066]
【The invention's effect】
  As described above, according to the present invention,,flatSince the pseudo-convex lens can be formed by the carrier layer, and the planarization layer can be made thinner and the surface can be formed more flat, high photosensitivity can be obtained even when an insulating film is formed on the semiconductor substrate.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a manufacturing process of a microlens in a method for manufacturing a solid-state imaging device according to a first embodiment of the present invention, and is a cross-sectional view of the solid-state imaging device in each step.
FIG. 2 is a top view of the solid-state imaging device manufactured by the manufacturing method according to the first embodiment of the present invention.
FIG. 3 is a diagram illustrating a manufacturing process of a microlens in a method for manufacturing a solid-state imaging device according to a second embodiment of the present invention, and is a cross-sectional view of the solid-state imaging device in each step.
FIG. 4 is a cross-sectional view illustrating a structure of a solid-state imaging device manufactured by a manufacturing method according to a second embodiment of the present invention.
FIG. 5 is a cross-sectional view showing a structure of a solid-state imaging device according to a third embodiment of the present invention.
FIG. 6 is a cross-sectional view showing a structure of a solid-state imaging device according to a fourth embodiment of the present invention.
FIG. 7 is a diagram showing a planarization layer manufacturing process in a method for manufacturing a solid-state imaging device according to a fourth embodiment of the present invention, and is a cross-sectional view of the solid-state imaging device in each step.
FIG. 8 is a cross-sectional view illustrating an exemplary structure of a conventional solid-state imaging device.
FIG. 9 is a view of a conventional solid-state imaging device as viewed from above.
FIG. 10 is a cross-sectional view illustrating the structure of another example of a conventional solid-state imaging device.
[Explanation of symbols]
  10 Micro lens
  10a Lens resist
  10b Lens pattern
  10c micro lens
  11 Semiconductor substrate
  12 Photodiode section
  13 First planarization layer
  14 Color filter
  15 Second planarization layer
  16 Interlayer insulation film
  18 Lens mask
  20 Microlens
  20a Lens resist
  20b Lens pattern
  20c micro lens
  30 First planarization layer
  31 Pseudo-convex lens
  32 First planarization layer
  33 Pseudo-convex lens
  50 micro lens

Claims (6)

A semiconductor substrate having a light receiving portion for converting incident light into electric charge and having a light receiving portion region formed in a concave shape; an insulating film formed on the semiconductor substrate and having the light receiving portion region recessed in a concave shape; and the insulating film In a solid-state imaging device provided with a planarizing layer formed on the insulating film and planarizing the surface of the insulating film,
The planarizing layer is made of a material having a higher refractive index than the insulating film ,
A solid-state imaging device , wherein a pseudo convex lens is formed by the insulating film and the planarizing layer in a concave portion of the insulating film . The insulating film and the planarizing layer include a silicon oxide film and a phenol resin film, a fluorine resin film and a silicon oxide film, a fluorine resin film and an acrylic resin film, a fluorine resin film and a phenol resin film, and fluorine. A resin film and a polyimide resin film, a silicon oxide film and an acrylic resin film, a silicon oxide film and a polyimide resin film, and an acrylic resin film and a phenolic resin film. Have
The solid-state imaging device according to claim 1. The material for forming the planarizing layer is a material that dissolves in a liquid state by heating.
The solid-state imaging device according to claim 1. The insulating film is a fluorine resin film, a silicon oxide film or an acrylic resin film,
The planarizing layer is made of a phenol-based thermoplastic resin.
The solid-state imaging device according to claim 3. An insulating film forming step of forming an insulating film on a semiconductor substrate having a light receiving portion and having a light receiving portion region formed in a concave shape, and a flattening layer for forming a flattening layer for flattening the surface of the insulating film on the insulating film In a method for manufacturing a solid-state imaging device comprising a formation layer forming step,
The planarization layer formation step, viewed contains a step of forming the planarizing layer of a material having a refractive index higher than that of the insulating film,
In the insulating film forming step and the flattening layer forming step, the insulating film and the flattening layer are divided into a silicon oxide film and a phenol resin film, a fluorine resin film and a silicon oxide film, a fluorine resin film and an acrylic resin. Film, fluorine resin film and phenol resin film, fluorine resin film and polyimide resin film, silicon oxide film and acrylic resin film, silicon oxide film and polyimide resin film, and acrylic resin film and phenol resin A method for manufacturing a solid-state imaging device, wherein the solid-state imaging device is formed by a combination of any one of the films . An insulating film forming step of forming an insulating film on a semiconductor substrate having a light receiving portion and having a light receiving portion region formed in a concave shape, and a flattening layer for forming a flattening layer for flattening the surface of the insulating film on the insulating film In a method for manufacturing a solid-state imaging device comprising a formation layer forming step,
In the planarizing layer forming step, the planarizing layer is formed of a material having a refractive index higher than that of the insulating film and dissolved in a liquid state by heating, and the material is dissolved by heating to flatten the surface of the planarizing layer. the step of viewing including,
In the insulating film forming step, a fluorine resin film, a silicon oxide film or an acrylic resin film is formed as the insulating film,
The method for manufacturing a solid-state imaging device , wherein in the planarization layer forming step, the planarization layer is formed of a phenol-based thermoplastic resin .

Images