JP2011009389A - Solid-state image pickup device and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid-state image pickup device improved in sensitivity and excellent in reduction of color mixture, and a method for manufacturing the device with ease.SOLUTION: A silicon lens 40 is provided between a photodiode 31 and an on-chip micro lens 63. Since the silicon lens 40 and a silicon layer 14 are both the same silicon layer, reflection can be suppressed. Reflection of light is suppressed by a reflection preventing film on the surface of the silicon lens 40 to obtain an improved light condensing factor and improved sensitivity. Failure of color mixture is reduced as well since multiplex reflection is suppressed.

Description

  The present invention relates to a solid-state imaging device having a so-called back-illuminated structure and imaging using a photoelectric conversion element, and a method for manufacturing the solid-state imaging device.

  Conventionally, in a solid-state imaging device called a CCD image sensor or a CMOS image sensor, a light receiving sensor and a wiring for connecting each light receiving sensor are formed on the surface of the substrate, and light is irradiated on the surface to be converted in the light receiving sensor region. The surface illumination type structure that picks up and picks up electrical signals is common, but as the solid-state imaging device becomes more miniaturized, the pitch of the wiring becomes narrower and the wiring layer becomes multilayered. It has become difficult to reach the surface of the light receiving sensor region with sufficient strength.

As an improvement plan, there has been proposed a solid-state imaging device having a back-illuminated structure in which light is irradiated from the side opposite to the surface on which the light receiving sensor region and the wiring are formed.
FIG. 22 is a cross-sectional view showing the structure of a conventional back-illuminated solid-state imaging device (Patent Document 1).

  This Patent Document 1 discloses a CMOS type solid-state imaging device to which a backside illumination type structure is applied. As shown in FIG. 22, in the solid-state imaging device of this example, a multilayer wiring layer 130 is provided on one surface (back surface) side of a supporting silicon substrate 110 via a two-layer silicon oxide film 120 such as an antireflection film. A thin flat single crystal silicon substrate 142 is laminated on the multilayer wiring layer 130, and a plurality of photoelectric conversion elements (hereinafter referred to as photodiodes) 150 are formed on the single crystal silicon substrate 142. Each photodiode 150 is formed by using the back surface side of the single crystal silicon substrate 142 as a light receiving portion, and further, the color filter 170 and the on-chip micros are formed on the back surface side of the single crystal silicon substrate 142 via an interlayer insulating film 160. A lens 180 is provided.

Next, a manufacturing method of the solid-state imaging device disclosed in Patent Document 1 will be briefly described with reference to process cross-sectional views illustrating the conventional manufacturing method of the solid-state imaging device shown in FIGS.
First, in FIG. 23, a two-layer substrate of a silicon oxide substrate 141 and a single crystal silicon substrate 142 is manufactured. As the two-layer substrate, one obtained by bonding the substrates or an SOI substrate is used.

Next, in FIG. 24, the single crystal silicon substrate 142 is thinned by overall etching or the like to obtain a silicon substrate 140 having a thickness of about 5 μm.
Subsequently, as shown in FIG. 25, an element such as a photodiode 150 is formed in the single crystal silicon substrate 142. In this case, the light receiving portion of the photodiode 150 is formed toward the silicon oxide substrate 141 side. Then, a multilayer wiring layer 130 is formed on the single crystal silicon substrate 142.

  As shown in FIG. 26, a support silicon substrate 110 is bonded to the upper portion through a two-layer silicon oxide film 120 to improve mechanical strength, and then the back side is obtained by grinding, etching, or using them together. The silicon oxide substrate 141 is removed.

  Thereafter, as shown in FIG. 22, the above-described thin interlayer insulating film 160, color filter 170, and on-chip microlens 180 are formed on the single crystal silicon substrate 142 (on the back surface side), and the conventional back surface irradiation is performed. Type solid-state imaging device is formed.

JP 2005-259828 A

  However, the conventional solid-state imaging device has a structure in which only the on-chip microlens is arranged above the light receiving portion. Therefore, the sensitivity is insufficient due to the miniaturization of the pixel portion, and the interlayer film on the photodiode surface and the color filter bottom surface There is a problem that sensitivity is lowered due to multiple reflections of incident light at the light source and color mixing occurs due to light leakage to adjacent photodiodes.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a solid-state imaging device excellent in sensitivity improvement and color mixing reduction with an easy manufacturing method, and a manufacturing method thereof.

  In order to achieve the above object, a solid-state imaging device according to the present invention includes a semiconductor substrate on which a plurality of light receiving portions are formed, a multilayer wiring layer formed on a first surface of the semiconductor substrate, and the semiconductor An antireflection film formed on a second surface opposite to the first surface of the substrate, and a plurality of antireflection films formed on the antireflection film corresponding to each of the plurality of light receiving portions. A microlens and a plurality of convex portions formed on the second surface of the semiconductor substrate at positions corresponding to the plurality of light receiving portions, respectively.

  Further, a plurality of color filters formed corresponding to each of the plurality of light receiving portions between the second surface of the semiconductor substrate and the microlens, and depending on the colors of the plurality of color filters, The heights of the plurality of convex portions may be different.

  Furthermore, the method for manufacturing a solid-state imaging device according to the present invention includes a step of forming a plurality of light receiving portions on a semiconductor substrate, a step of forming a multilayer wiring layer on the first surface of the semiconductor substrate, Forming an antireflection film on the second surface opposite to the first surface, and forming a plurality of microlenses on the antireflection film corresponding to each of the plurality of light receiving portions. And a step of forming a plurality of convex portions corresponding to each of the plurality of light receiving portions on the second surface of the semiconductor substrate.

The convex portion may have a lens shape.
Further, the step of forming the plurality of convex portions may be performed between the step of forming the laminated wiring layer and the step of forming the antireflection film.

Further, the step of forming the plurality of convex portions may be performed before the step of forming the laminated wiring layer.
Further, the step of forming the plurality of convex portions includes a step of forming a resist pattern at a position corresponding to each of the plurality of light receiving portions on the second surface of the semiconductor substrate, and the resist pattern And the step of simultaneously etching the second surface of the semiconductor substrate.

The resist pattern may be hemispherical.
In addition, after the step of forming the antireflection film, the resist pattern further includes a step of forming a plurality of color filters on the second surface of the semiconductor substrate corresponding to each of the plurality of light receiving portions. In the step of forming the resist pattern, the resist pattern can be formed so that the height of the resist pattern differs depending on the colors of the plurality of color filters.

  As described above, the light collection rate is improved, and the sensitivity can be improved and color mixing can be reduced.

  According to the solid-state imaging device of the present invention, even if the miniaturization and the increase in the number of pixels are advanced, it is easy to form an uneven silicon layer such as a lens shape between the light receiving unit and the on-chip microlens. In the light transmitted through the concavo-convex shape silicon layer in the manufacturing method, the concavo-convex shape portion and the silicon layer on which the light receiving portion is formed are the same material silicon layer, so that reflection by different refractive index film interfaces can be suppressed. it can. Further, an antireflection film can be easily formed on the top of the concavo-convex silicon layer, and reflection of light on the concavo-convex light receiving surface can be suppressed. Due to these reflection suppression effects, the light collection rate can be improved and the sensitivity can be improved. Furthermore, since multiple reflections at different refractive index film interfaces can be suppressed, light entering into adjacent photodiodes can be suppressed, and color mixing defects can be reduced.

Sectional drawing which shows the structure of the solid-state imaging device in 1st Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 1st Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 1st Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 1st Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 1st Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 1st Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 1st Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 1st Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 1st Example of this invention Sectional drawing which shows the structure of the solid-state imaging device in 2nd Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 2nd Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 2nd Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 2nd Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 2nd Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 2nd Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 2nd Example of this invention Sectional drawing which shows the structure of the solid-state imaging device in 3rd Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 3rd Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 3rd Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 3rd Example of this invention Process sectional drawing which shows the manufacturing method of the solid-state imaging device in 3rd Example of this invention Sectional view showing the structure of a conventional back-illuminated solid-state imaging device Process sectional drawing which shows the manufacturing method of the conventional solid-state imaging device Process sectional drawing which shows the manufacturing method of the conventional solid-state imaging device Process sectional drawing which shows the manufacturing method of the conventional solid-state imaging device Process sectional drawing which shows the manufacturing method of the conventional solid-state imaging device

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Here, an example of a lens-shaped structure will be described with respect to the concavo-convex shape formed of the silicon layer above the light receiving portion.
(First embodiment)
FIG. 1 is a cross-sectional view showing the structure of a solid-state imaging device according to the first embodiment of the present invention.

  FIG. 1 shows a part of a solid-state imaging device having a light receiving sensor, wherein 14 is a silicon layer (single crystal silicon layer), 31 is a photodiode, 32 is a first insulating film, 33 is a contact plug, and 34 is Second insulating film, 35 is wiring, 36 is a multilayer wiring layer, 37 is a first adhesive layer, 38 is a second adhesive layer, 39 is a supporting silicon substrate, 40 is a silicon lens made of a silicon layer, 52 is an oxide Antireflection film comprising two layers of silicon film 50 and silicon nitride film 51, 60 is a color filter (compatible with Blue), 61 is a color filter (compatible with Green), 62 is a color filter (compatible with Red), and 63 is an on-chip microlens It is.

Next, a first embodiment of the solid-state imaging device and the manufacturing method thereof according to the present invention described above will be described in detail.
2 to 9 are process cross-sectional views illustrating the method of manufacturing the solid-state imaging device according to the first embodiment of the present invention, and portions corresponding to those in FIG.

  First, as shown in FIG. 2, an SOI substrate 15 comprising a silicon substrate 12, a silicon oxide film 13, and a silicon layer 11 is prepared, and an impurity region constituting a light receiving sensor such as a photodiode 31 is formed in the silicon layer 11. To do. Although not shown, a transistor gate electrode and the like are also formed on the surface of the silicon layer 11 and impurity regions constituting the transistor in the silicon layer 11.

  Next, as shown in FIG. 3, a first insulating film 32 such as a silicon oxide film is formed on the surface of the silicon layer 11, and a contact plug 33 is formed in the first insulating film 32. Then, a second insulating film 34 such as a silicon oxide film is formed on the first insulating film 32, and the light receiving sensor region is electrically connected to the second insulating film 34, for example, a wiring 35 such as copper. And the multilayer wiring layer 36 is formed.

  Next, as shown in FIG. 4, a first adhesive layer 37 such as a silicon oxide film is formed on the surface of the multilayer wiring layer 36, and the surface is polished flat. Then, a supporting silicon substrate 39 on which a second adhesive layer 38 such as a silicon oxide film is formed is prepared so that the silicon oxide films of the first adhesive layer 37 and the second adhesive layer 38 are connected to each other. The multilayer wiring layer 36 formed on the surface of the SOI substrate 15 and the support substrate 39 are bonded together.

  Next, as shown in FIG. 5, the SOI substrate 15 and the support substrate 39 are turned upside down, and the silicon substrate 12 of the SOI substrate 15 on the upper surface is subjected to CMP, RIE, BGR, or these three methods. Then, the silicon oxide film 13 on the back surface of the silicon substrate 12 is removed by a CMP method, an RIE method, or the like. As a result, since the silicon layer 11 is exposed on the light receiving side of the light receiving portion, the light receiving surface of the silicon layer 11 can be formed into a lens shape thereafter.

  Next, as shown in FIG. 6, after forming a resist pattern on the dots by lithography technology on the surface of the silicon layer 11 on the light receiving side of the photodiode 31, for example, hemisphere or lens by melting by heat treatment such as melt baking. A resist pattern 23 having a shape like the shape is formed.

  Next, as shown in FIG. 7, the resist pattern 23 and the silicon layer 11 are etched to form the silicon layer 14 by dry etching technology under the condition that, for example, a chlorine or bromine halogen gas is added with a CF or oxygen gas. Form. At this time, a silicon lens 40 made of a hemispherical or lens-shaped silicon layer is formed on the surface of the silicon layer 14 on the light receiving side of the photodiode 31.

Next, as shown in FIG. 8, a two-layer antireflection film 52 composed of a silicon oxide film 50 and a silicon nitride film 51 is formed on the silicon lens 40.
Next, as shown in FIG. 9, a color filter 60 corresponding to Blue, a color filter 61 corresponding to Green, and a color filter 62 corresponding to Red are formed on the antireflection film 52 which is an upper region of each photodiode. Then, an on-chip microlens 63 is formed thereon to complete the solid-state imaging device.

  As described above, in the method for manufacturing a solid-state imaging device of the present invention, the silicon lens 40 is provided between the photodiode 31 and the on-chip microlens 63, and the silicon layer 14 on which the photodiode 31 is formed is a silicon lens. Since the light is transmitted through the silicon lens 40, reflection from a different refractive index film interface can be suppressed. Further, since the lens shape (convex shape) of the silicon lens 40 is formed on the silicon layer 14, oblique light or the like can be efficiently collected on the photodiode 31, and the structure of the silicon lens can be maintained while maintaining the structure. An antireflection film can be easily formed on the upper portion, light reflection on the surface of the silicon lens can be suppressed, and the light collection rate can be further improved, so that the sensitivity can be improved.

  Further, since the silicon lens 40 having a lens shape (convex shape) formed of the same material is formed on the silicon layer 14, multiple reflections at different refractive index film interfaces can be suppressed, so that light enters an adjacent photodiode. And color mixing defects can be reduced.

In this way, it is possible to improve sensitivity and prevent color mixing with an easy manufacturing method, thus enabling further miniaturization and higher pixel count, and further enhancement of functions for mobile phone cameras, movie cameras, and digital still cameras. Can contribute.
(Second embodiment)
Next, FIG. 10 is a cross-sectional view showing the structure of the solid-state imaging device in the second embodiment of the present invention.

FIG. 10 shows a part of a solid-state imaging device having a light receiving sensor. In this embodiment, lens-shaped irregularities are previously formed in the silicon back surface layer when the SOI substrate is formed.
17 is a silicon layer (single crystal silicon layer) having a lens-shaped silicon lens 41 on the back surface, 31 is a photodiode, 32 is a first insulating film, 33 is a contact plug, 34 is a second insulating film, and 35 is Wiring, 36 is a multilayer wiring layer, 37 is a first adhesive layer, 38 is a second adhesive layer, 39 is a supporting silicon substrate, 41 is a silicon lens made of a silicon layer, 52 is a silicon oxide film 50 and a silicon nitride film 51. 2 is an antireflection film, 60 is a color filter (compatible with Blue), 61 is a color filter (compatible with Green), 62 is a color filter (compatible with Red), and 63 is an on-chip microlens.

Next, a second embodiment of the method for manufacturing the solid-state imaging device according to the present invention will be described in detail.
FIGS. 11 to 16 are process cross-sectional views illustrating a method of manufacturing a solid-state imaging device according to the second embodiment of the present invention, and portions corresponding to those in FIG.

  First, as shown in FIG. 11, an SOI substrate 18 comprising a silicon substrate 12, a silicon oxide film 16, and a silicon layer 17 having a lens shape in advance on the back side is prepared, and a photodiode 31 and the like are provided in the silicon layer 17. Impurity regions constituting the light receiving sensor are formed. Although not shown, a transistor gate electrode and the like are also formed on the surface of the silicon layer 17 and the impurity region constituting the transistor in the silicon layer 17.

  Next, as shown in FIG. 12, a first insulating film 32 such as a silicon oxide film is formed on the surface of the silicon layer 17, and a contact plug 33 is formed in the first insulating film 32. Then, a second insulating film 34 such as a silicon oxide film is formed on the first insulating film 32, and the light receiving sensor region is electrically connected to the second insulating film 34, for example, a wiring 35 such as copper. And the multilayer wiring layer 36 is formed.

  Next, as shown in FIG. 13, a first adhesive layer 37 such as a silicon oxide film is formed on the surface of the multilayer wiring layer 36, and the surface is polished flat. Then, a supporting silicon substrate 39 on which a second adhesive layer 38 such as a silicon oxide film is formed is prepared so that the silicon oxide films of the first adhesive layer 37 and the second adhesive layer 38 are connected to each other. A multilayer wiring layer 36 formed on the SOI substrate 18 and a supporting silicon substrate 39 are bonded together.

  Next, as shown in FIG. 14, the SOI substrate 18 and the supporting silicon substrate 39 are turned upside down, and the silicon substrate 12 of the SOI substrate 18 on the upper surface is subjected to CMP, RIE, BGR, or these three Then, the silicon oxide film 16 on the back surface of the silicon substrate 12 is removed by a CMP method, an RIE method, or the like. As a result, the silicon lens 41 made of a silicon layer having a lens shape is exposed on the light receiving side of the light receiving unit.

Next, as shown in FIG. 15, a two-layer antireflection film 52 including a silicon oxide film 50 and a silicon nitride film 51 is formed on the light receiving surface of the silicon lens 41.
Next, as shown in FIG. 16, a color filter 60 corresponding to Blue, a color filter 61 corresponding to Green, and a color filter 62 corresponding to Red are formed on the light receiving surface of the antireflection film 52, On-chip microlenses 63 are formed thereon to complete the solid-state imaging device.

  As described above, in the method of manufacturing the solid-state imaging device according to the present invention, the lens shape is previously formed on the back surface of the silicon layer 17 when the SOI substrate is created so that the positional relationship between the light receiving unit and the silicon lens 41 can be easily controlled. Even in this case, the same structure as that of the first embodiment can be created, and the light collection efficiency can be improved and the color mixing failure can be reduced by an easy manufacturing method.

(Third embodiment)
Next, FIG. 17 is a cross-sectional view showing the structure of a solid-state imaging device according to the third embodiment of the present invention.

  FIG. 17 shows a part of a solid-state imaging device having a light receiving sensor, 19 is a silicon layer (single crystal silicon layer), 31 is a photodiode, 32 is a first insulating film, 33 is a contact plug, and 34. Is a second insulating film, 35 is a wiring, 36 is a multilayer wiring layer, 37 is a first adhesive layer, 38 is a second adhesive layer, 39 is a supporting silicon substrate, and 42 is a first silicon lens made of a silicon layer. 43 is a second silicon lens made of a silicon layer, 44 is a third silicon lens made of a silicon layer, 52 is an antireflection film made of two layers of a silicon oxide film 50 and a silicon nitride film 51, and 60 is a color filter ( (Blue), 61 is a color filter (green), 62 is a color filter (red), and 63 is an on-chip microlens.

Next, a third embodiment of the solid-state imaging device and the manufacturing method thereof according to the present invention described above will be described in detail.
18 to 21 are process cross-sectional views illustrating the method of manufacturing the solid-state imaging device according to the third embodiment of the present invention, and portions corresponding to those in FIG.

  In the third embodiment, from the preparation of the SOI substrate 15 (see FIG. 2 and the like), the formation of the photodiode 31, the formation of the multilayer wiring layer 36, the bonding of the supporting silicon substrate 39, and the silicon oxide film 13 of the SOI substrate 15 (FIG. 2). Since the manufacturing method is the same as the manufacturing method described in FIGS. 2 to 5 of the first embodiment until the removal, the description by illustration is omitted, and the light receiving surface of the silicon layer 11 of the SOI substrate 15 is exposed. The process will be described.

  As shown in FIG. 18, a dot-like resist pattern is formed on the light receiving surface side surface of the light receiving portion of the photodiode 31 in the silicon layer 11 by lithography. At this time, by exposing a photodiode corresponding to each color to a mask corresponding to each color, for example, by exposing a mask having a different light transmittance to each photodiode, the resist height of the dot-shaped resist pattern corresponds to each color. Change by diode. Thus, for example, three kinds of resist patterns 25, 26, and 27 having a hemispherical shape with different heights are formed by melting by heat treatment such as melt baking.

  Next, as shown in FIG. 19, resist patterns 25, 26, and 27 are formed by dry etching technique, for example, under the condition that CF and oxygen gases are added to the chlorine and bromine halogen gases described in the first embodiment. The surface of the silicon layer 11 is etched to form a silicon layer 19. At this time, silicon lenses 42, 43, and 44 made of a hemispherical or lens-shaped silicon layer are formed on the light receiving surface of the photodiode 31, and each of the silicon lenses 42, 43, and 44 has a lens height corresponding to each color. It depends on the photodiode. For example, when the silicon lens 42 corresponds to blue, the silicon lens 43 corresponds to green, and the silicon lens 44 corresponds to red, the silicon lens 42 is the lowest and the silicon lens 44 is the highest.

Next, as shown in FIG. 20, a two-layer antireflection film 52 composed of a silicon oxide film 50 and a silicon nitride film 51 is formed on the light receiving surfaces of the silicon lenses 42, 43, 44.
Next, as shown in FIG. 21, the light receiving surface of the antireflection film 52 corresponds to each photodiode, the light receiving surface of the silicon lens 42 corresponds to the color filter 60 corresponding to Blue, and the light receiving surface of the silicon lens 43. The color filter 61 corresponding to Green and the color filter 62 corresponding to Red are formed on the light receiving surface of the silicon lens 44, and the on-chip microlens 63 is formed thereon to complete the solid-state imaging device.

  As described above, in the method for manufacturing a solid-state imaging device according to the present invention, first, as in the case of the embodiment, it is possible to improve the light collection rate and reduce the color mixing failure with an easy manufacturing method. Further, by adjusting the height of the silicon lens shape of the light receiving surface of the photodiode corresponding to each color, the distance from the top of the silicon lens shape to the photodiode 31 is set to a distance suitable for the wavelength of each color, so that each color The photoelectric conversion efficiency of each light receiving sensor can also be improved.

  More specifically, it is preferable that the longer the wavelength of light, the higher the silicon lens. In addition, although the present embodiment shows an example in which the height of the lens-shaped silicon lens is changed, the height may be made equal and the curvature of the lens may be changed. It is preferable to form the lens with a large curvature.

  Further, in the manufacturing method of the present embodiment, the silicon lens having a different shape for each color is formed after the multilayer wiring layer is formed as in the first embodiment, but is formed before the multilayer wiring is formed as in the second embodiment. Is also possible.

  In the above description, an example in which an SOI substrate is used has been described. However, even when a normal silicon substrate is used, it is possible to form a silicon lens by processing and forming the back surface. Needless to say.

  Furthermore, although the CMOS image sensor is premised as a manufacturing method of the solid-state imaging device of the present invention, the present invention can be similarly applied to solid-state imaging devices having other configurations having a backside illumination structure.

  For example, the present invention can be applied to form a silicon lens in a CCD solid-state imaging device or the like having a back-illuminated structure.

  INDUSTRIAL APPLICABILITY The present invention can improve sensitivity and reduce color mixing, has a so-called back-illuminated structure, and is useful for a solid-state imaging device that captures an image using a photoelectric conversion element, a method for manufacturing the solid-state imaging device, and the like.

11, 14, 17, 19 Silicon layer (single crystal silicon layer)
DESCRIPTION OF SYMBOLS 12 Silicon substrate 13, 16 Silicon oxide film 15, 18 SOI substrate 23 Resist pattern 25 Resist pattern 26 Resist pattern 27 Resist pattern 31 Photodiode 32 1st insulating film 33 Contact plug 34 2nd insulating film 35 Wiring 36 Multilayer wiring layer 37 first adhesive layer 38 second adhesive layer 39 support silicon substrate 40 silicon lens 41 silicon lens 42 silicon lens 43 silicon lens 44 silicon lens 50 silicon oxide film 51 silicon nitride film 52 antireflection film 60 color filter (Blue)
61 Color filter (Green)
62 Color filter (Red)
63 On-chip microlens 110 Support silicon substrate 120 Silicon oxide film 130 Multilayer wiring layer 140 Silicon substrate 141 Silicon oxide substrate 142 Single crystal silicon substrate 150 Photodiode 160 Interlayer insulating film 170 Color filter 180 On-chip microlens

Claims (10)

A semiconductor substrate on which a plurality of light receiving portions are formed;
A multilayer wiring layer formed on the first surface of the semiconductor substrate;
An antireflection film formed on a second surface opposite to the first surface of the semiconductor substrate;
A plurality of microlenses formed on the antireflection film corresponding to each of the plurality of light receiving units,
A solid-state imaging device comprising: a plurality of convex portions formed on the second surface of the semiconductor substrate at positions corresponding to the plurality of light receiving portions.   The solid-state imaging device according to claim 1, wherein the convex portion has a lens shape. A plurality of color filters formed corresponding to each of the plurality of light receiving portions between the second surface of the semiconductor substrate and the microlens;
The solid-state imaging device according to claim 1, wherein heights of the plurality of convex portions are different depending on colors of the plurality of color filters. Forming a plurality of light receiving portions on a semiconductor substrate;
Forming a multilayer wiring layer on the first surface of the semiconductor substrate;
Forming an antireflection film on a second surface opposite to the first surface of the semiconductor substrate;
Forming a plurality of microlenses corresponding to each of the plurality of light receiving portions on the antireflection film, and corresponding to each of the plurality of light receiving portions on the second surface of the semiconductor substrate. The manufacturing method of the solid-state imaging device characterized by further including the process of forming a plurality of convex parts.   The method of manufacturing a solid-state imaging device according to claim 4, wherein the convex portion has a lens shape.   6. The step of forming the plurality of convex portions is performed between the step of forming the laminated wiring layer and the step of forming the antireflection film. Manufacturing method of solid-state imaging device.   6. The method for manufacturing a solid-state imaging device according to claim 4, wherein the step of forming the plurality of convex portions is performed before the step of forming the laminated wiring layer. The step of forming the plurality of convex portions includes:
Forming a resist pattern on the second surface of the semiconductor substrate at a position corresponding to each of the plurality of light receiving portions;
8. The method of manufacturing a solid-state imaging device according to claim 4, further comprising a step of simultaneously etching the resist pattern and the second surface of the semiconductor substrate.   The method of manufacturing a solid-state imaging device according to claim 8, wherein the resist pattern is hemispherical. After the step of forming the antireflection film, further comprising the step of forming a plurality of color filters on the second surface of the semiconductor substrate corresponding to each of the plurality of light receiving portions,
10. The solid-state imaging according to claim 8, wherein, in the step of forming the resist pattern, the resist pattern is formed so that a height of the resist pattern varies depending on colors of the plurality of color filters. Device manufacturing method.

Images