JP2006351855A - Solid state imaging device and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a solid state imaging device comprising an intra-layer lens between a top lens and a photoelectric conversion device capable of efficiently condensing light on the photoelectric conversion device, even when the light is incident obliquely. <P>SOLUTION: The solid state imaging device 1 comprises the photoelectric conversion device 11 arranged on a semiconductor substrate 10, a light-shielding layer 13, a second protective film 17, the intra-layer lens 20 formed on the second protective film 17 correspondingly to the location wherein the photoelectric conversion device 11 is formed, a surface planarizing layer 30, and the top lens 40 formed on the surface planarizing layer 30 correspondingly to the location wherein the photoelectric conversion device 11 is formed. The intra-layer lens 20 is constructed of a material having a refractive index equal or nearly equal to that of the surface planarizing layer 30, and is constructed of a convex lens having an upwardly convex lens-shape and a side wall constructed of a material having a refractive index larger than that of the convex lens portion and covering around the side face of the convex lens portion. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a solid-state imaging device having an in-layer lens that efficiently collects light on a photoelectric conversion device, and a method for manufacturing the same.

  Since the solid-state imaging device in which the photoelectric conversion elements are arranged two-dimensionally includes the photoelectric conversion unit and the signal reading unit on the surface of the semiconductor substrate, the region actually contributing to the photoelectric conversion has an aperture ratio of about 20 to 40%. Limited to In order to limit the aperture ratio, a method of condensing incident light on a photoelectric conversion unit by providing a condensing lens for each pixel is generally employed. Also, a method using an in-layer lens in addition to the above-mentioned condensing lens is proposed to improve the condensing rate with respect to incident light incident obliquely on the surface of the solid-state imaging device (semiconductor substrate). (For example, refer to Patent Document 1).

  FIG. 8 is a cross-sectional view schematically showing the structure of a solid-state imaging device having a conventional intralayer lens. The solid-state imaging device 101 includes a first insulating layer 112, a metal wiring 113 patterned in a predetermined shape, and a metal wiring 113 that protects the metal wiring 113 on a semiconductor substrate 110 in which photoelectric conversion elements 111 are two-dimensionally arranged. One protective film 114, a planarization layer 115, a light shielding layer 116 for shielding the metal wiring 113, and a second protective film 117 for protecting the light shielding layer 116 are sequentially stacked, and photoelectric conversion is performed. An in-layer lens 120 is formed at a position on the second protective film 117 corresponding to a position at which the element 111 is formed, and a surface flattening layer 130 is formed on the light-shielding layer 116 and the in-layer lens 120. The top lens 140 is formed at a position on the surface flattening layer 130 corresponding to the position at which 111 is formed. Of these, the intralayer lens 120 is formed at a position on the planarization layer 115 corresponding to the position where the photoelectric conversion element 111 is formed, and has a core 121 having a rectangular cross-sectional shape, and a side surface of the core 121. The side wall 122 is formed in a curved shape in contact with the periphery. In the intralayer lens 120, the interface between the core portion 121 and the sidewall 122 is linear and extends in a direction perpendicular to the substrate surface of the semiconductor substrate 110.

JP 2003-204050 A

  The in-layer lens 120 is configured to have a refractive index equal to or greater than a predetermined value in order to collect light that cannot be collected by the top lens 140 onto the photoelectric conversion element 111. Therefore, when light is incident on the surface of the solid-state imaging device 101 at an angle, the incident light passes through the top lens 140 and the in-layer lens 120 and is collected on the photoelectric conversion device 111 formed on the surface of the semiconductor substrate 110. To be lighted.

  However, as shown in the left half of FIG. 8, when light having an angle larger than a predetermined angle is incident on the surface of the solid-state imaging device 101, the core portion 121 of the in-layer lens 120. And the sidewall 122 extend linearly in a direction perpendicular to the substrate surface of the semiconductor substrate 110, so that light cannot be reflected to the photoelectric conversion element 111, and There is a problem that it becomes impossible to collect light.

  The present invention has been made in view of the above, and in a solid-state imaging device including an in-layer lens between a top lens and a photoelectric conversion device, the light collection efficiency of light incident perpendicularly to the surface of the solid-state imaging device An object of the present invention is to obtain a solid-state imaging device capable of efficiently condensing light incident obliquely on a photoelectric conversion device and a method for manufacturing the same without dropping the light.

  In order to achieve the above object, a solid-state imaging device according to the present invention includes a photoelectric conversion element disposed on a semiconductor substrate, a light shielding layer that shields light to a predetermined position on the semiconductor substrate, and the light shielding layer. A protective film formed so as to cover; a first lens formed on the protective film corresponding to a formation position of the photoelectric conversion element; and a surface flatness covering the first lens and flattening the surface And a second lens formed on the surface flattening layer corresponding to a formation position of the photoelectric conversion element, wherein the first lens is the surface flattening layer. A convex lens portion having a convex lens shape and a material having a refractive index larger than that of the convex lens portion, and a side surface portion of the convex lens portion. Around A sidewall covering the, characterized in that it is constituted by.

  According to the present invention, the convex lens portion has a convex lens portion having a curved outer peripheral surface between the photoelectric conversion element and the top lens formed on the surface of the solid-state imaging device, and the material having a refractive index larger than that of the convex lens portion. Since an intra-layer lens composed of sidewalls formed around the side surfaces is provided, light that is incident obliquely on the surface of the solid-state imaging device is formed into a curved surface shape between the convex lens portion and the sidewalls. Reflection can be caused at the interface and the light can be condensed on the photoelectric conversion element on the semiconductor substrate. As a result, it has the effect that it can respond to the light of the incident angle of the wide range which injects into a solid-state image sensor.

  Exemplary embodiments of a solid-state imaging device and a method for manufacturing the same according to the present invention will be described below in detail with reference to the accompanying drawings. However, the cross-sectional views of the solid-state imaging device used in the following embodiments are schematic, and the relationship between the thickness and width of the layers, the ratio of the thicknesses of the layers, and the like are different from the actual ones.

Embodiment 1 FIG.
FIG. 1 is a diagram schematically showing a cross-sectional structure of a first embodiment of a solid-state imaging device according to the present invention. The solid-state imaging device 1 includes an insulating layer 12, a metal wiring 13 patterned in a predetermined shape at a predetermined position, and a metal wiring 13 on a semiconductor substrate 10 on which a photoelectric conversion element 11 is formed two-dimensionally on the surface. A first protective film 14 for protecting the metal, a planarization layer 15 for planarizing unevenness caused by the metal wiring 13 on the insulating layer 12, and a predetermined shape at a predetermined position to block light from entering the metal wiring 13 The second light-shielding layer 16 patterned in the second protective film 17 for protecting the surface of the light-shielding layer 16 (corresponding to the protective film in the claims), the second corresponding to the formation position of the photoelectric conversion element 11 An in-layer lens 20 (corresponding to the first lens in the claims) formed on the protective film 17, a surface flattening layer 30 for flattening irregularities due to the light shielding layer 16 and the in-layer lens 20, and Photoelectric conversion element 1 correspond to the positions of formation of the topped lens 40 formed on the surface planarization layer 30 (corresponding to the second lens in the claims) is, which are stacked in this order.

  FIG. 2 is a cross-sectional view schematically showing the structure of the in-layer lens. The intralayer lens 20 used for the solid-state imaging device 1 is formed between the semiconductor substrate 10 and the top lens 40 in correspondence with the formation position of the photoelectric conversion element 11 on the semiconductor substrate 10 as described above. . The intra-layer lens 20 is formed corresponding to the formation position of the photoelectric conversion element 11, and the side surface of the inner layer lens 20 is perpendicular to the substrate surface of the semiconductor substrate 10 and is in contact with the side surface of the core portion 21. First sidewall 22 formed (corresponding to the sidewall portion in the convex lens portion in the claims) and second sidewall 23 formed in contact with the outer side surface of the first sidewall 22 (patent Corresponding to the sidewalls in the claims). Among these, the core portion 21 and the first sidewall 22 are formed of the same material, such as plasma Si—O, having a value that is the same as or close to the refractive index of the surface planarization layer 30, and the second sidewall. 23 is formed of a material such as plasma Si—N having a higher refractive index than the first sidewall 22. In addition, the interface between the first sidewall 22 and the second sidewall 23 is configured by a curved surface so that light reflected by this interface is guided to the photoelectric conversion element.

  By configuring the intralayer lens 20 as described above, the difference in refractive index between the core portion 21 and the surface flattening layer 30 can be reduced, and the incident light is perpendicular to the surface of the solid-state imaging device 1. For the light to be reflected, reflection on the surface of the inner lens 20 can be suppressed. Further, for light incident obliquely on the surface of the solid-state imaging device 1, the incident light is converted at the interface by the difference in refractive index between the first and second sidewalls 22 and 23. The light reflected by the curved interface can be condensed onto the photoelectric conversion element 11.

  Next, a method for manufacturing the solid-state imaging device 1 having such a structure will be described. 3A to 3D are cross-sectional views schematically showing an example of the procedure of the method for manufacturing the solid-state imaging device according to the present invention. However, in the following, a procedure for forming the intralayer lens 20 which is a feature of the first embodiment is mainly shown. First, the photoelectric conversion element 11 is formed on the semiconductor substrate 10 by a known method, and the insulating layer 12 is formed on the upper surface thereof. A metal wiring 13 having a predetermined shape is formed at a predetermined position on the upper surface of the insulating layer 12 by a photolithography technique and an etching technique, and the metal wiring 13 and the insulating layer 12 on which the metal wiring 13 is not formed are covered. After forming the first protective film 14, a planarizing layer 15 for planarizing the unevenness caused by the metal wiring 13 is formed. Thereafter, a light shielding layer 16 having a predetermined shape is formed on the planarization layer 15 by a photolithography technique and an etching technique so as to cover the formation position of the lower metal wiring 13, and the planarization layer on which the light shielding layer 16 is formed. A second protective film 17 is formed on the substrate 15 (FIG. 3A).

  Next, a transparent film for forming a lens such as plasma Si—O having a predetermined thickness is formed on the second protective film 17, and a resist is formed at a predetermined position by photolithography. This resist is left only at a position where the core portion 21 of the intralayer lens 20 is formed in a position corresponding to the position where the photoelectric conversion element 11 is formed on the semiconductor substrate 10 and is removed at other portions. Thereafter, the unnecessary transparent film for lens formation is removed by a reactive ion etching method (hereinafter referred to as RIE method). After removing the unnecessary lens forming transparent film, the resist is removed to form a portion corresponding to the core portion 21 having the columnar structure of the in-layer lens 20 (FIG. 3-2).

  Next, a first sidewall-forming transparent film 22a made of plasma Si—O or the like of the same material as the core 21 is formed so as to cover the core 21 of the in-layer lens 20 (FIG. 3-3). The first sidewall forming transparent film 22a is also formed with an unnecessary first sidewall so as to have a sidewall shape surrounding the side surface of the core portion 21 by using a photolithography method and an RIE method. The first sidewall 22 is formed by etching the transparent film 22a for use.

Next, a second sidewall forming film such as Si ₃ N ₄ having a refractive index higher than that of the core 21 of the inner lens 20 and the first sidewall 22 is formed on the core 21 of the inner lens 20 and the second film. A film is formed so as to cover one side wall 22. Also for the second sidewall formation film, unnecessary second sidewall formation is performed around the side surface of the first sidewall 22 by using a photolithography method, an RIE method, or the like. The second sidewall 23 is formed by etching the working film (FIGS. 3-4). Thus, the in-layer lens 20 is formed.

  Thereafter, a surface flattening layer 30 is formed on the inner lens 20 formed on the second protective film 17 by flattening the surface with a predetermined thickness. Then, by forming the top lens 40 at a position on the surface flattening layer 30 corresponding to the formation position of the photoelectric conversion element 11 on the semiconductor substrate 10, the solid-state imaging element 1 as shown in FIG. 1 is formed. The

  According to the first embodiment, between the photoelectric conversion element 11 and the top lens 40 formed on the surface of the solid-state imaging device 1, the core 21 and the side surface of the core 21 are made of the same material as the core 21. Around the side surface of the first side wall 22 with a material having a refractive index larger than that of the core 21 and the first side wall 22. Since the in-layer lens 20 composed of the formed second sidewall 23 is provided, the light incident obliquely with respect to the surface of the solid-state imaging device 1 is converted into the first and second sidewalls. It is possible to cause reflection at the curved interface with 22 and 23 and to focus on the photoelectric conversion element 11 on the semiconductor substrate 10. As a result, there is an effect that it can be operated corresponding to light having a wide range of incident angles incident on the solid-state imaging device 1.

  In addition, since the core portion 21 and the first sidewall 22 of the intralayer lens 20 are formed in separate steps, it is possible to divert the sidewall formation step of the gate electrode structure in the conventional semiconductor device. In addition, the conventional process and apparatus can be effectively used.

Embodiment 2. FIG.
FIG. 4 is a diagram schematically showing a cross-sectional structure of the second embodiment of the solid-state imaging device according to the present invention. This solid-state imaging device 1A is a convex lens in which the core 21 and the first sidewall 22 of the inner lens 20 formed on the second protective film 17 are integrally formed in FIG. 1 of the first embodiment. It has an intra-layer lens 20 </ b> A constituted by the portion 24 and a sidewall 25 corresponding to the second sidewall 23. In addition, the same code | symbol is attached | subjected to the component same as Embodiment 1, and the description is abbreviate | omitted.

  The intralayer lens 20A according to the second embodiment includes a convex lens portion 24 that is formed into a convex lens shape that is convex upward using a material having a refractive index that is the same as or close to that of the surface planarizing layer 30, and a side surface of the convex lens portion 24. And a sidewall 25 made of a material having a refractive index larger than that of the convex lens portion 24. Since the sidewall 25 is formed around the outer side surface of the convex lens portion 24, the interface between the convex lens portion 24 and the sidewall 25 is curved as in the first embodiment.

  Next, a manufacturing method of the solid-state imaging device 1A having such a structure will be described. 5A to 5C are cross-sectional views schematically showing an example of the procedure of the method for manufacturing the solid-state imaging device according to the present invention. As shown in FIG. 3A of the first embodiment, a photoelectric device in which an insulating layer 12, a metal wiring 13, a first protective film 14, a planarizing layer 15, a light shielding layer 16, and a second protective film 17 are formed in this order. A convex lens portion constituting film 24A made of plasma Si—O or the like for forming the convex lens portion 24 is formed on the semiconductor substrate 10 having the conversion element 11 with a predetermined thickness (FIG. 5-1). Thereafter, a resist 26 having a convex lens shape is formed at a position on the convex lens portion constituting film 24A corresponding to the formation position of the photoelectric conversion element 11 by photolithography (FIG. 5-2). Next, the convex lens portion constituting film 24A and the resist 26 are simultaneously etched by the RIE method or the like to form the convex lens portion 24 at a position corresponding to the formation position of the photoelectric conversion element 11 (FIG. 5-3). For example, by adjusting the etching rate of the convex lens portion constituting film 24A and the convex lens-shaped resist 26 to substantially the same ratio, the portion covered with the resist 26 of the convex lens portion constituting film 24A and the convex lens portion 24 having the convex lens shape are formed. can do.

  Thereafter, as described with reference to FIGS. 3-4 of the first embodiment, a sidewall forming film constituted by a refractive index larger than that of the convex lens portion 24 is formed on the second protective film 17 on which the convex lens portion 24 is formed. Then, a sidewall 25 is formed on the outer periphery of the side surface of the convex lens portion 24 by a photolithography method, an RIE method, or the like. Thus, the in-layer lens 20A is formed. Next, a surface flattening layer 30 having a predetermined thickness is formed on the intralayer lens 20 </ b> A formed on the second protective film 17. Then, the top lens 40 is formed at a position on the surface flattening layer 30 corresponding to the formation position of the photoelectric conversion element 11 on the semiconductor substrate 10, thereby forming the solid-state imaging element 1 </ b> A as shown in FIG. 4. The

  According to the second embodiment, in addition to the effects of the first embodiment, the convex lens portion 24 of the in-layer lens 20A is separated from the core portion 21 and the first sidewall 22 as in the first embodiment. It can be manufactured in a single process without forming.

Embodiment 3 FIG.
FIG. 6 is a diagram schematically showing a cross-sectional structure of the solid-state imaging device according to the third embodiment of the present invention. In FIG. 4 of the second embodiment, the solid-state imaging device 1B integrally forms the convex lens portion 24 of the in-layer lens 20A with the second protective film 17A (corresponding to the protective film in the claims). It is characterized by that. In addition, the same code | symbol is attached | subjected to the component same as Embodiment 1, 2, and the description is abbreviate | omitted.

  The intralayer lens 20B of the third embodiment is formed simultaneously with the formation of the second protective film 17A by using the same material as that of the second protective film 17A. That is, the convex lens portion 27 of the in-layer lens 20B is formed on the second protective film 17A. More specifically, an upward convex convex lens portion 27 is formed at a position on the second protective film 17A corresponding to the formation position of the photoelectric conversion element 11 on the semiconductor substrate 10, and this convex lens portion 27 is formed. By forming the sidewall 28 made of a material having a refractive index larger than that of the convex lens portion 27 so as to cover the periphery of the side surface of the lens, the in-layer lens 20B is formed. Since the side wall 28 is formed around the side surface of the convex lens portion 27, the interface between the convex lens portion 27 and the side wall 28 is curved as in the first embodiment.

  Next, a manufacturing method of the solid-state imaging device 1B having such a structure will be described. 7A to 7D are cross-sectional views schematically showing an example of the procedure of the method for manufacturing the solid-state imaging device according to the present invention. However, in the following, a procedure for forming the intralayer lens 20B, which is a feature of the third embodiment, is mainly shown. Similar to the procedure described in FIG. 3A of Embodiment 1, the insulating layer 12, the metal wiring 13, the first protective film 14, the planarization layer 15, and the light shielding are formed on the semiconductor substrate 10 having the photoelectric conversion element 11. The layer 16 is formed in order (FIG. 7-1). Next, a second protective film 17A made of plasma Si—O or the like having a predetermined thickness is formed on the planarizing layer 15 on which the light shielding layer 16 is formed (FIG. 7-2). The second protective film 17A needs to be thicker than the thickness of the second protective film 17A in the case of the first embodiment, and the thickness thereof is higher than the upper surface portion of the light shielding layer 16. is there. For example, as shown in FIG. 6, the thickness of the second protective film 17A on the upper surface of the light shielding layer 16 is the same as that of the second protective film 17A formed in the first embodiment. The height (thickness) is added or thicker. Further, the surface of the second protective film 17A at this time is flattened.

  Thereafter, a resist 26 having a convex lens shape is formed at a position on the second protective film 17A corresponding to the photoelectric conversion element 11 on the semiconductor substrate 10 (FIG. 7-3). Next, the convex lens part 27 is formed at a position corresponding to the photoelectric conversion element 11 by simultaneously etching the convex lens part constituting film 24A and the resist 26 by the RIE method or the like (FIG. 7-4). Also in this case, as in the second embodiment, for example, the etching rate of the second protective film 17A and the convex lens-shaped resist 26 is adjusted to approximately the same ratio to cover the second protective film 17A with the resist 26. The broken portion can be processed into a convex lens portion 27 having a convex lens shape.

  Thereafter, as described with reference to FIGS. 3-4 of the first embodiment, a sidewall forming film having a refractive index larger than that of the convex lens portion 27 is formed on the second protective film 17A on which the convex lens portion 27 is formed. The sidewall 28 is formed on the outer periphery of the side surface of the convex lens portion 27 by photolithography and RIE. Then, a surface flattening layer 30 having a predetermined thickness is formed on the second protective film 17A having the intralayer lens 20B so that the surface is flattened, and the photoelectric conversion element 11 on the semiconductor substrate 10 is formed. By forming the top lens 40 at a position on the surface flattening layer 30 corresponding to the position, the solid-state imaging device 1 as shown in FIG. 6 is formed.

  According to the third embodiment, in addition to the effects of the first embodiment, the convex lens portion 27 of the in-layer lens 20B can be manufactured in the same process as the second protective film 17A, and the in-layer lens 20B. The manufacturing process can be simplified.

  As described above, the solid-state imaging device according to the present invention is useful for an imaging apparatus for efficiently collecting light incident from various angles with respect to the surface.

It is a figure which shows typically the cross-section of Embodiment 1 of the solid-state image sensor by this invention. It is sectional drawing which shows the structure of a 1st lens typically. It is sectional drawing which shows typically an example of the procedure of the manufacturing method of the solid-state image sensor by this invention (the 1). It is sectional drawing which shows typically an example of the procedure of the manufacturing method of the solid-state image sensor by this invention (the 2). It is sectional drawing which shows typically an example of the procedure of the manufacturing method of the solid-state image sensor by this invention (the 3). It is sectional drawing which shows typically an example of the procedure of the manufacturing method of the solid-state image sensor by this invention (the 4). It is a figure which shows typically the cross-section of Embodiment 2 of the solid-state image sensor by this invention. It is sectional drawing which shows typically an example of the procedure of the manufacturing method of the solid-state image sensor by this invention (the 1). It is sectional drawing which shows typically an example of the procedure of the manufacturing method of the solid-state image sensor by this invention (the 2). It is sectional drawing which shows typically an example of the procedure of the manufacturing method of the solid-state image sensor by this invention (the 3). It is a figure which shows typically the cross-section of Embodiment 3 of the solid-state image sensor by this invention. It is sectional drawing which shows typically an example of the procedure of the manufacturing method of the solid-state image sensor by this invention (the 1). It is sectional drawing which shows typically an example of the procedure of the manufacturing method of the solid-state image sensor by this invention (the 2). It is sectional drawing which shows typically an example of the procedure of the manufacturing method of the solid-state image sensor by this invention (the 3). It is sectional drawing which shows typically an example of the procedure of the manufacturing method of the solid-state image sensor by this invention (the 4). It is sectional drawing which shows typically the structure of the solid-state image sensor which has the conventional intralayer lens.

Explanation of symbols

1, 1A, 1B Solid-state imaging device 10 Semiconductor substrate 11 Photoelectric conversion device 12 Insulating layer 13 Metal wiring 14 First protective film 15 Planarizing layer 16 Light-shielding layer 17, 17A Second protective film 20, 20A, 20B Intralayer lens 21 Core 22 First Side Wall 23 Second Side Wall 24 Convex Lenses 25, 28 Side Wall 27 Convex Lens Part 30 Surface Flattening Layer 40 Top Lens

Claims (6)

A photoelectric conversion element disposed on a semiconductor substrate;
A light shielding layer for shielding light to a predetermined position on the semiconductor substrate;
A protective film formed to cover the light shielding layer;
A first lens formed on the protective film corresponding to the formation position of the photoelectric conversion element;
A surface planarization layer covering the first lens and planarizing the surface;
A second lens formed on the surface flattening layer corresponding to the formation position of the photoelectric conversion element;
In a solid-state imaging device comprising:
The first lens is
A convex lens portion made of a material having a material having the same or close refractive index as that of the surface planarization layer and having a convex lens shape;
A side wall made of a material having a refractive index larger than that of the convex lens part and covering the periphery of the side part of the convex lens part,
A solid-state imaging device comprising: The convex lens part is
A columnar core portion made of a material having a refractive index equal to or close to that of the surface planarizing layer;
Consists of the same material as the core part, covers the side surface of the core part, the outer side surface has a curved surface in the convex lens part sidewall,
The solid-state imaging device according to claim 1, comprising:   The solid-state imaging device according to claim 1, wherein the convex lens portion is integrally formed with the protective film. Convex lens part forming step of forming a convex lens part on the top by laminating a predetermined layer on a semiconductor substrate on which a photoelectric conversion element is arranged, and forming an in-layer lens at a position corresponding to the formation position of the photoelectric conversion element When,
A sidewall forming step of forming a sidewall around the side surface of the convex lens portion with a material having a refractive index larger than that of the material constituting the convex lens portion;
A surface flattening layer forming step of forming a surface flattening layer covering the convex lens portion and flattening the surface with a material having a refractive index which is the same as or close to the refractive index of the material constituting the convex lens portion;
A top lens forming step of forming a top lens convex upward at a position corresponding to the formation position of the photoelectric conversion element on the surface flattening layer;
The manufacturing method of the solid-state image sensor characterized by including. The convex lens part forming step includes
Forming a layer made of a convex lens component material on the semiconductor substrate, leaving a columnar core having a side surface perpendicular to the substrate surface at a position corresponding to the position where the photoelectric conversion element is formed. A core forming step for processing;
A convex lens part side wall forming step of forming the convex lens part side wall part so as to cover the side surface of the core part and have an outer side surface having a curved surface by the same material as the core part;
The manufacturing method of the solid-state image sensor of Claim 4 characterized by the above-mentioned. The convex lens part forming step includes
A protective film forming step of forming a protective film for protecting a lower layer formed on the semiconductor substrate;
A convex lens part processing step of processing the protective film so as to form the convex lens part at a position corresponding to the formation position of the photoelectric conversion element in the protective film;
The manufacturing method of the solid-state image sensor of Claim 4 characterized by the above-mentioned.

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