JP2007311563A - Solid-state imaging apparatus, and electronic information equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To further improve the photosensitivity of each pixel even if the pixel size is further shrunk and suppress a deterioration of characteristics of the pixels due to the F value, in a solid-state imaging apparatus wherein the position of a light receiving portion changes periodically. <P>SOLUTION: In the solid-state imaging apparatus 10 wherein each photo diode 11 has a slanting pixel cell so that the arrangement of each photo diode 11 may change periodically in the row and column directions, four pixels are grouped which have the periodicity. In each group of four pixels, upper-layer microlenses 12A for condensing image light are arranged for the individual pixels, and a lower-layer microlens 12B is so arranged as to cover the four pixels straddling them and bends the lights condensed by the upper-layer microlenses 12A. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a solid-state imaging device such as a CCD image sensor or a CMOS image sensor provided with a microlens above a light-receiving unit that photoelectrically converts light, and the solid-state imaging device used as an image input device in an imaging unit, for example. The present invention relates to electronic information devices such as digital cameras such as digital video cameras and digital still cameras, image input cameras, scanners, facsimiles, and camera-equipped mobile phone devices.

  In general, in a conventional solid-state imaging device such as a CCD type image sensor or a CMOS type image sensor, a light receiving portion such as a photodiode is provided in a pixel cell arranged in an array, and signal charges photoelectrically converted by the light receiving portion. Is output as an output imaging signal.

  For example, in the case of a CCD type image sensor, the pixel cell has the light receiving portion, a channel stop portion for separating adjacent pixels, and a signal charge read from the light receiving portion to transfer charges in the vertical direction. And a plurality of vertical charge transfer units. The signal charge transferred in the vertical charge is transferred in the horizontal direction by the horizontal charge transfer unit, converted into an electrical signal by the MOS transistor in the FD (floating diffusion) unit, and output as an imaging signal from the solid-state imaging device to the outside. The

  In the case of a CMOS type image sensor, since the signal charge is photoelectrically converted into an electrical signal in each pixel, the pixel cell includes the light receiving unit, a channel stop unit for separating adjacent pixels, and the light receiving unit. A transfer gate section for reading signal charges, an FD (floating diffusion) section for converting the read signal charges into electric signals, a MOS transistor, and a metal wiring are included.

  Furthermore, since the light irradiated to the part other than the light receiving part is not photoelectrically converted, each pixel cell has a microlens above the light receiving part in order to efficiently collect the light that becomes an invalid area on the light receiving part. Is provided.

  However, when the positions of the light receiving portions in the unit pixel are not arranged at the same pitch (arrangement interval) in the row direction or the column direction, the central portion of the light receiving portion and the optical axis of the microlens are shifted, and the light receiving sensitivity is increased. There is a problem of lowering.

  In order to solve this problem, for example, Patent Document 1 proposes the following conventional solid-state imaging device.

  FIG. 11 is a top view showing a schematic configuration example of a main part of a conventional solid-state imaging device proposed in Patent Document 1, and FIG. 12 shows a portion of the conventional solid-state imaging device shown in FIG. It is a longitudinal cross-sectional view at the time of cut | disconnecting by.

  11 and 12, in the conventional solid-state imaging device 20, the photodiodes 22a to 22d constituting four pixels having periodicity are grouped into one group among a plurality of pixel cells 21 arranged in an array. The on-chip microlens 23 is formed so that the optical axis C coincides with the central portion of each of the photodiodes 22a to 22d constituting the four pixels. In this case, one microlens 23 corresponds to the four photodiodes 22a to 22d, and the optical axis C of the microlens 23 separates the photodiodes 22a to 22d of the four pixels in plan view. The channel stop portion 24 of the book is located at the cross portion.

  FIG. 13 is a longitudinal sectional view showing a schematic configuration example of a main part of a conventional solid-state imaging device proposed in Patent Document 2.

In FIG. 13, the conventional solid-state imaging device 30 is configured such that the photodiodes 32a and 32b constituting two pixels having periodicity in one direction form one group, and the central portions of the photodiodes 32a and 32b constituting two pixels. Each of the microlenses 33, the interlayer insulating film 34 disposed between the microlenses 33 and the photodiodes 32a and 32b, the protective film 35 thereon, and the color filter layer 36 thereon. Is formed. In this case, the interlayer insulating film 34 and the protective film 35 are made of light transmitting materials having different refractive indexes, and the interface between the interlayer insulating film 34 and the protective film 35 is connected to the microlens 33 and each photodiode 32a or 32b. It is comprised so that it may have an inclination part according to the amount of plane position shift.
JP-A-5-243543 JP 2005-150492 A

  However, the conventional solid-state imaging device 20 proposed in Patent Document 1 has the following problems.

  FIG. 14 is a longitudinal sectional view of the conventional solid-state imaging device 20 shown in FIG. 11 taken along the line AA ′. FIG. 12 shows the center of the light receiving region where the image light is incident from directly above. It is a figure which shows the mode of condensing to each photodiode in a part, whereas it is a figure showing the state of condensing to each photodiode in the peripheral part of the light-receiving region where light enters from an oblique direction is there.

  As shown in FIG. 12, in the conventional solid-state imaging device 20, the image light condensed on the cross portion of the channel stop unit 24 from the microlens 23 around the optical axis C is respectively reflected by the photodiodes 22 a to 22 d. Since photoelectric conversion cannot be performed, the light receiving sensitivity is reduced in each pixel by the amount of light on the cross portion.

  Further, as shown in FIG. 14, when oblique light having a small F (focus) value and a large angle is incident, the photodiodes 21c that are arranged adjacent to each other by an amount corresponding to the defocusing direction of the microlens 23 are shifted. , 21d are different, and the characteristics of each pixel are different. In particular, when the color filter 25 is provided, image light from the color layer adjacent to the color layer of the corresponding color filter 25 may be incident on the photodiodes 22c and 22d and color mixing may occur. Further, the image light incident on the peripheral edge of the microlens 23 is blocked by the metal wiring layers 26a to 26c provided above the photodiodes 22c and 22d depending on the incident direction, and is directed to the photodiode 22c or 22d. There is also a possibility that the incidence of the light is hindered.

  Further, in the solid-state imaging device of Patent Document 2, as shown in FIG. 13, the interface between the interlayer insulating film 34 and the protective film 35 corresponds to the amount of planar positional deviation between the microlens 33 and each photodiode 32a or 32b. Although it has an inclined portion, the valley-shaped inclined portion is configured so that the condensing by the microlens 33 is shifted only in one direction according to the degree of proximity of the photodiodes 32a and 32b. However, in this solid-state imaging device, when the number of pixels having periodicity is not two, but when the number of pixels is four as shown in FIG. 11, the condensed light protrudes from the light receiving unit in another direction different from one direction. Sensitivity decreases, and as a result, the amount of light incident on the photodiodes that are adjacent to each other is different, resulting in different characteristics for each pixel or color mixing. Furthermore, when the pixel size is further reduced, the light condensing protrudes from the light receiving portion even in the one direction, so that the light receiving sensitivity is lowered. The amount of incident light is different, and the characteristics of each pixel are different or color mixing occurs.

  The present invention solves the above-described conventional problems. In a solid-state imaging device in which the positions of light receiving portions are periodically different, even when the pixel size is further reduced, the light receiving sensitivity of each pixel is further improved. It is an object of the present invention to provide a solid-state imaging device capable of suppressing deterioration of pixel characteristics due to values and an electronic information device using the solid-state imaging device in an imaging unit.

  A solid-state imaging device according to the present invention is a solid-state imaging device including a plurality of light receiving units arranged so that their positions are periodically different, and a microlens for condensing light on each of the plurality of light receiving units. Are grouped into a predetermined number of light receiving units having periodicity, and for each group, the microlens is disposed above the predetermined number of light receiving units with the first microlens arranged for each light receiving unit. A second microlens that covers the cover, thereby achieving the object.

  Preferably, the second microlens in the solid-state imaging device of the present invention has a circular, elliptical, rectangular, or square planar view shape, and at least an outer peripheral portion of the planar view shape is formed into a lens curved surface shape. ing.

  Further preferably, in the second microlens in the solid-state imaging device of the present invention, a central portion inside the outer peripheral portion in the plan view is formed in a lens curved surface shape or a planar shape.

  Still preferably, in a solid-state imaging device of the present invention, the second microlens is provided between the predetermined number of light receiving units and the first microlens.

  Still preferably, in a solid-state imaging device according to the present invention, the first microlens is located in an upper layer than the second microlens.

  Still preferably, in a solid-state imaging device according to the present invention, the second microlens is configured such that light collected by each first microlens arranged for each light receiving unit is arranged inside each predetermined number of light receiving units having the periodicity. It is configured to bend.

  Further, preferably, the cross-sectional shape of the second microlens in the solid-state imaging device of the present invention is a convex lens shape up, down or up and down.

  Furthermore, preferably, the cross-sectional shape of the first microlens in the solid-state imaging device of the present invention is a convex lens shape up, down or up and down.

  Furthermore, preferably, the first microlens and the second microlens in the solid-state imaging device of the present invention are arranged so that light is collected at the center of each light receiving unit.

  Further preferably, in the solid-state imaging device according to the present invention, a metal wiring layer is provided between the light receiving unit and the first micro lens and the second micro lens above the light receiving unit. .

  Further preferably, in the solid-state imaging device of the present invention, the first microlens is provided in an upper layer than the color filter layer, and the second microlens is provided in a lower layer than the color filter layer.

  Further preferably, the plurality of light receiving units in the solid-state imaging device of the present invention are arranged so as to be periodically different in at least one of one direction and a direction crossing the one direction in plan view. .

  Further preferably, the plurality of light receiving units in the solid-state imaging device of the present invention are provided in a matrix in the column direction and the row direction in plan view, and are periodically different in at least one direction of the column direction and the row direction. Has been placed.

  Still preferably, in a solid-state imaging device according to the present invention, the predetermined number of light receiving units having periodicity is a group of a total of four pixels of two pixels each in the column direction and the row direction in plan view.

  Further preferably, in the solid-state imaging device according to the present invention, the predetermined number of light receiving units having the periodicity are grouped into two pixels in the column direction or the row direction in plan view.

  Further preferably, in the solid-state imaging device of the present invention, for each of the grouped four pixels, the four light receiving portions are formed evenly on the cross portion side of the channel stop portion between the adjacent pixels. ing.

  Further preferably, in the solid-state imaging device according to the present invention, the lower-layer microlens extending over the grouped four pixels has a light beam at a cross portion of the channel stop unit, which is the center of the four light receiving units constituting the four pixels. It is provided so that the axes coincide.

  Further preferably, in the solid-state imaging device of the present invention, for each of the two grouped pixels, two of the light receiving portions are formed evenly on the channel stop portion side between adjacent pixels.

  Further preferably, in the solid-state imaging device according to the present invention, the lower-layer microlens straddling the two grouped pixels has an optical axis at the channel stop portion which is the center between the two light receiving portions constituting the two pixels. It is provided to match.

  Further preferably, in the solid-state imaging device of the present invention, the group is arranged such that light incident on the first microlens is condensed through the second microlens at the same position on the light receiving unit corresponding to each of the groups. When some or all of the formed first microlenses adjacent to each other are made to approach each other beyond the peripheral edge portions of the lenses, they are formed in a lens shape in which the overlapping lens portions are cut out and adjacent to each other.

  Further preferably, in the solid-state imaging device according to the present invention, the first microlenses adjacent to each other are formed so that at least a part of the peripheral portion of the first microlens overlaps the adjacent first microlens.

  Further preferably, in the solid-state imaging device according to the present invention, the first microlenses adjacent to each other are arranged such that the lens shapes obtained by cutting out the overlapping lens portions are in contact with each other.

  Further preferably, in the solid-state imaging device of the present invention, the first microlenses adjacent to each other are arranged such that lens shapes obtained by cutting the overlapping lens portions are separated from each other by a predetermined gap.

  Further preferably, in the solid-state imaging device of the present invention, the position of the first microlens is arranged differently according to the interval of the light receiving portions.

  Further preferably, in the solid-state imaging device of the present invention, the light receiving unit and the first microlens are periodically arranged in units of N pixels (N is an integer of 2 or more) so that the positions of the light receiving unit and the first microlens are periodically different from each other. ing.

  Further preferably, in the solid-state imaging device of the present invention, the positions of the light receiving unit and the first microlens are arranged in a matrix, respectively, and I pixels (I is an integer of 2 or more) and columns in the row direction The pixels are periodically arranged in units of K pixels (K = I × J) in J pixels (J is an integer of 2 or more).

  Furthermore, preferably, in the solid-state imaging device of the present invention, one output amplifier is shared for each of the predetermined number of light receiving units.

  Still preferably, in a solid-state imaging device according to the present invention, the light receiving unit is a photoelectric conversion unit that photoelectrically converts light.

  Further preferably, the solid-state imaging device of the present invention is a CCD type image sensor or a CMOS type image sensor.

  An electronic information device according to the present invention uses the solid-state imaging device according to the present invention as an imaging unit, thereby achieving the object.

  The operation of the present invention will be described below with the above configuration.

  In the present invention, a predetermined number (for example, 2 or 4) of pixels having periodicity in a solid-state imaging device in which arrangement intervals of a plurality of light receiving portions are periodically different in at least one of the row direction and the column direction. Are grouped, and each group has a first microlens arranged for each pixel and a second microlens arranged over a predetermined number of grouped pixels.

  In this way, even when the pixel size is further reduced by providing two or more types of microlenses, the light receiving invalid area is reduced while condensing by the two upper and lower microlenses, thereby increasing the light condensing rate. Thus, it is possible to efficiently collect the image light on the central portion of the light receiving portion and improve the light receiving sensitivity of each pixel. In addition, even when oblique light is incident on the periphery of the light receiving region, the image light is collected by the upper first microlens, and the center of the optical axis is centered on the light receiving portion of each pixel by the lower second microlens. Since it can be easily and reliably matched to the part, it is possible to reduce variations in light collection rate and color mixing from pixel to pixel, and to suppress characteristic deterioration of each pixel.

  In addition, since the first microlenses in the upper layer adjacent to each other can be arranged close to the position where the outer peripheral portions overlap each other, even when the pixel size is further reduced, the light receiving sensitivity is improved and the pixel size is reduced. It becomes possible to suppress characteristic deterioration.

  Since the first microlens and the second microlens are formed above the metal wiring layer, it is possible to prevent light collection from being hindered by the metal wiring above the light receiving portion.

  As described above, according to the present invention, even when the pixel size is further reduced in the solid-state imaging device in which the arrangement intervals of the plurality of light receiving units are periodically different, the two upper and lower first microlenses and second microlenses are used. While condensing, the light reception invalid area is reduced to increase the light collection rate to improve the light reception sensitivity in each pixel, and the light collection rate that occurs when oblique light with a large angle is incident on the periphery of the light reception region, etc. The pixel characteristics can be improved, for example, the variation in color and color mixing can be reduced and the characteristic deterioration of each pixel can be suppressed.

Embodiments 1 to 5 of the solid-state imaging device of the present invention will be described in detail below with reference to the drawings.
(Embodiment 1)
FIG. 1 is a plan view illustrating a schematic configuration example of a main part of a solid-state imaging device according to Embodiment 1 of the present invention, and FIG. 2 illustrates a case where the solid-state imaging device illustrated in FIG. 1 is cut along a line BB ′. FIG.

  1 and 2, the solid-state imaging device 10 according to the first embodiment includes a plurality of photodiodes 11 as a plurality of light receiving units arranged so that positions thereof are periodically different, and a plurality of photodiodes 11 on the plurality of photodiodes 11. Each has a microlens 12 for condensing image light.

  The plurality of photodiodes 11 are photoelectric conversion units that photoelectrically convert light, and are arranged so as to be periodically different in the row direction and the column direction in plan view, and have four photodiodes 11a having periodicity. ˜11d form one group for every four pixels in total in the row direction and the column direction in plan view.

  The microlens 12 covers the upper microlens 12A as a first microlens arranged for each photodiode 11 and the four photodiodes 11a to 11d that are grouped with periodicity. And a lower microlens 12B as a second microlens. The lower microlens 12B has a predetermined number (four in this case) having periodicity of the respective light collections by the four upper microlenses 12A. The photodiodes 11 that are close to each other are bent with respect to each central portion.

  The lower-layer microlens 12B is provided between the photodiode 11 and the upper-layer microlens 12A. The upper-layer microlens 12A and the lower-layer microlens 12B have a rectangular shape or a square shape in plan view, and their cross-sectional shapes are both An upwardly convex lens shape (lower surface is a flat surface).

  These photodiodes 11a to 11d and the microlens 12 constitute a matrix array of pixel cells 14 (14a to 14d) partitioned by two striped channel stop portions 13, and each pixel One photodiode 11 and one upper microlens 12A correspond to each of the cells 14a to 14d. The upper layer microlens 12A is provided for each pixel so as to substantially cover each of the pixel cells 14a to 14d.

  The arrangement intervals of the photodiodes 11a to 11d in the pixel cells 14a to 14d are periodically different in the row direction and the column direction. In the first embodiment, the pixel cells adjacent to each other are grouped by four pixels. The channel stop portion 13 between 14a to 14d is formed close to the cross portion. In other words, the lower microlens 12 </ b> B is grouped as a group for each of the four pixel cells 14 a to 14 d that are adjacent to and close to the channel stop unit 13, and each group covers four pixels. Is provided and shared by the four pixel cells 14a to 14d. The lower layer microlens 12B is provided so that the optical axis C coincides with the center of the four pixel cells 14a to 14d (cross portion of the channel stop portion 13).

  The operation of the above configuration will be described below.

  FIG. 3 is a cross-sectional view of the solid-state imaging device 10 of FIG. 1 taken along the line BB ′, and FIG. 2 shows a state of light condensing on the photodiode when light is incident from directly above. FIG. 4 is a diagram showing a state of light condensing on a photodiode when image light is incident from an oblique direction. Here, it will be described in detail in comparison with FIGS. 11 and 13 showing the conventional solid-state imaging device 20.

  First, when each pixel cell 14 is a central portion of the light receiving area and image light is incident on each pixel cell 14 from directly above, the conventional solid-state imaging device 20 has a center of the optical axis C as shown in FIG. Is located at the center of four pixels having periodicity, this portion corresponds to a cross portion of the channel stop portion 24 for separating the four pixels. Therefore, the image light condensed on the cross portion cannot be photoelectrically converted by the photodiodes 22a to 22d, and the light receiving sensitivity is reduced in each pixel.

  On the other hand, in the solid-state imaging device 10 according to the first embodiment, as shown in FIG. 2, the upper microlenses 12A and the lower microlenses 12B above and below the upper microlens 12A and the upper microlenses 12A on the left and right sides to some extent. Since the condensed image light can be bent so as to be brought inward by one lower microlens 12B, the center of the optical axis C of each of the upper microlenses 12A on the left and right is set to each central portion of each photodiode 22c and 12d. The light beams can be easily and reliably combined, and the image light can be condensed on the photodiodes 11a to 11d with higher light receiving efficiency.

  Next, when each pixel cell 14 is in the periphery of the light receiving region and image light is incident on each pixel cell 14 from an oblique direction, the conventional solid-state imaging device 20 has a small F value as shown in FIG. When oblique light having a large angle is incident from the upper right to the lower left, the amount of light incident on the left photodiode 22c is larger than that on the right photodiode 22d, and the light collection characteristics vary from pixel cell to pixel cell. Arise. In particular, when the color filter 25 is provided, image light that has passed through different color layers may be incident on the photodiode 22 of an adjacent pixel, and color mixing may occur in the photodiode 22.

  On the other hand, in the solid-state imaging device 10 according to the first embodiment, as shown in FIG. 3, the image light collected by the upper microlens 12A is a photodiode that is a light receiving unit by the lower microlens 12B below it. 11 is condensed so that its optical axis C is aligned with the central portion of the light source 11, so that even when oblique light is incident from the upper right to the lower left, the light is incident on the right photodiode 11 d and the left photodiode 11 c. There is no difference in the amount of light, there is little variation in light collection for each pixel, and color mixing can be reduced. Further, since the lower microlens 12B is formed in an upper layer than the metal wirings 8 to 10, the metal wirings 16a to 16d provided above the grouped photodiodes 11a to 11d and the photodiodes 11a to 11d. By 16c, it can prevent that condensing to each photodiode 11a-11d is prevented.

  Next, a method for manufacturing the solid-state imaging device 10 of Embodiment 1 will be described with reference to FIGS. 4A to 4C.

  4A to 4C are main part longitudinal cross-sectional views for explaining the respective manufacturing steps (Nos. 1 to 3) of the method for manufacturing the solid-state imaging device 10 according to the first embodiment. Here, a method of forming the lower-layer microlens 12B and the upper-layer microlens 12A having an upwardly convex lens shape will be described.

  First, as shown in FIG. 4A, the third-layer metal wiring 16c is etched to form a predetermined pattern, and then a planarization film 17 is formed thereon, and a microlens material 12b is formed thereon as a lower layer. Transfer and develop with a predetermined pattern of the microlens 12B.

  Next, as shown in FIG. 4B, the microlens material 12b is baked (heat treated) to form a lower microlens 12B that is convex upward.

  Thereafter, as shown in FIG. 4C, the planarizing film 18 is formed on the planarizing film 17 and the lower microlens 12B, and the microlens material 12a is transferred and developed in a predetermined pattern on the upper microlens 12A. . Further, the microlens material 12a is baked (heat treated) to form four upper-layer microlenses 12A that are convex upward for each lower-layer microlens 12B.

As described above, according to the first embodiment, by forming two types of microlenses 12, that is, the upper microlens 12 </ b> A disposed for each pixel and the lower microlens 12 </ b> B that covers the four pixels, Even in the solid-state imaging device 10 in which the arrangement of the photodiodes 11 as the light receiving portions in the cell 14 is periodically different in the row direction (horizontal direction) and the column direction (vertical direction), the light receiving sensitivity of each pixel is improved. It is possible to reduce color mixing and reduce color mixing.
(Embodiment 2)
In the first embodiment, the case of the upper microlens 12A and the lower microlens 12B having a convex lens shape has been described, but in the second embodiment, the upper microlens 12A has a convex lens shape. However, the case where the lower microlens 12C having a convex lens shape is used instead of the lower microlens 12B having a convex lens shape will be described.

  5 and FIG. 6 are longitudinal sectional views of the main part of the solid-state imaging device according to the second embodiment of the present invention, which is the same as that cut along the line BB ′ shown in FIG. 1, and FIG. FIG. 6 is a diagram showing a state of light condensing on each photodiode when image light is incident from FIG. 6, and FIG. 6 is a diagram showing a state of condensing on each photodiode when image light is incident from an oblique direction. . 5 and FIG. 6 correspond to FIG. 2 and FIG. 3 of the first embodiment, and members having the same operational effects as those of FIG. 2 and FIG. Yes.

  5 and 6, the solid-state imaging device 10A according to the second embodiment includes a plurality of photodiodes 11 as a plurality of light receiving units arranged so that positions thereof are periodically different, and a plurality of photodiodes 11 on the plurality of photodiodes 11. Each has a microlens 121 for condensing image light.

  The plurality of photodiodes 11 are photoelectric conversion units that photoelectrically convert light, and are arranged so as to be periodically different in the row direction and the column direction in plan view, and have four photodiodes 11a having periodicity. ˜11d form one group for every four pixels in total in the row direction and the column direction in plan view.

  The microlens 121 includes an upper microlens 12A serving as a first microlens arranged for each photodiode 11, and a second microlens that covers the upper part of each of the grouped four photodiodes 11a to 11d. And a lower-layer microlens 12C.

  The lower-layer microlens 12C is provided between the photodiode 11 and the upper-layer microlens 12A. The upper-layer microlens 12A has a rectangular shape or a square shape in plan view, and its cross-sectional shape is convex upward (single-sided The lower microlens 12C has a rectangular shape or a square shape in plan view, and its cross-sectional shape is a convex (upward convex on both sides) lens shape. Thus, when the lower layer microlens 12C is convex on both sides, the light condensing rate on the photodiode 11 is better than when the lower layer microlens 12B of the first embodiment is convex on one side. It becomes.

  Next, a method for manufacturing the solid-state imaging device 10A of Embodiment 2 will be described with reference to FIGS. 7A to 7E.

  7A to 7F are main part longitudinal cross-sectional views for describing each manufacturing process (Nos. 1 to 6) of the manufacturing method of the solid-state imaging device 10A of the second embodiment. Here, a method of forming the lower microlens 12C having a convex lens shape in the vertical direction and the upper microlens 12A having a convex lens shape in the upward direction will be described.

  First, as shown in FIG. 7A, after the third-layer metal wiring 16c is etched to form a predetermined pattern, a planarizing film 17 is formed thereon, and the planarizing film 17 is formed on the planarizing film 17. The resist film 7 having a selection ratio with respect to 17 of about 0.5 to 2.0 is transferred and developed. At this time, the resist film 7 is formed in a predetermined pattern so that the opening of the resist film 7 is disposed on the cross portion of the channel stop portion 13 between the photodiodes 11c and 11d adjacent to the left and right.

  Next, as shown in FIG. 7B, the resist film 7 is baked (heat treated) to form a resist film 7a having a concave-convex lens surface shape in which the channel stop portion 13 is most recessed. . At this time, the lowest position of the concave portion (center portion of the lens) is provided above the cross portion of the channel stop portion 13 between the photodiodes 11c and 11d adjacent to the left and right, and convex portions are provided on both sides thereof (around the lens). Yes.

  Further, as shown in FIG. 7C, anisotropic etching is performed on the concavo-convex resist film 7a to transfer the concavo-convex shape of the resist film 7a to the flattening film 17 to form a flattening film 17a.

  Subsequently, as shown in FIG. 7D, the microlens material 12a is transferred onto the planarizing film 17a in a predetermined pattern of the lower layer microlens 12C and developed.

  Thereafter, as shown in FIG. 7E, the microlens material 12a is baked (heat treated) to form a lower microlens 12C that is convex upward and downward (both sides convex).

  Further, as shown in FIG. 7F, the planarizing film 18 is formed on the planarizing film 17a and the lower microlens 12C, and the microlens material 12a is transferred and developed in a predetermined pattern of the upper microlens 12A. . Further, the microlens material 12a is baked (heat treated) to form four upper microlenses 12A that are convex upward for each lower microlens 12C.

As described above, according to the second embodiment, by forming the two types of microlenses 121, that is, the upper microlens 12 </ b> A arranged for each pixel and the lower microlens 12 </ b> C covering the four pixels, In the solid-state imaging device 10A in which the arrangement of the photodiodes 11 as the light receiving portions in the cell 14 is periodically different in the row direction (horizontal direction) and the column direction (vertical direction), as in the case of the first embodiment, It is possible to improve the light receiving sensitivity of each pixel, reduce the variation in light collection for each pixel, and reduce color mixing. In the second embodiment, the upper microlens 12A has an upwardly convex lens shape, but instead of the lower microlens 12B having a convex lens shape on the upper side (one side) of the first embodiment, the upper microlens 12A has a convex lens shape on the upper and lower sides (both sides). Since the lower microlens 12C is a double-sided convex shape, the light condensing rate on each of the photodiodes 11a to 11d is further improved as compared with the case of the single-sided convex shape of the first embodiment. Thus, even when the pixel size is further reduced, it is possible to improve the light receiving sensitivity of each pixel, reduce the variation in light collection for each pixel, and reduce color mixing.
(Embodiment 3)
In the first embodiment, the case of the upper-layer microlens 12A and the lower-layer microlens 12B having a convex lens shape has been described. However, in the third embodiment, the upper-layer microlens 12A having a convex lens shape, and A description will be given of the case of the lower-layer microlens 12D having a downward convex lens shape.

  FIG. 8 is a longitudinal sectional view of the main part of the solid-state imaging device according to the third embodiment of the present invention, which is the same as that cut along the line BB ′ shown in FIG. 1, and image light is incident from an oblique direction. It is a figure which shows the mode of condensing to each photodiode at the time. In addition, in FIG. 8, it respond | corresponds to FIG. 3 of the said Embodiment 1, and the same code | symbol is attached | subjected to the member which show | plays the same effect as the effect of FIG. In addition, regarding the state of light condensing on each photodiode when image light is incident from directly above corresponding to FIG. 2 of the first embodiment, the lower microlens having a lens shape convex upward in FIG. Although 12B will be described later with reference to FIG. 8, the lower microlens 12D having a downwardly convex lens shape may be used.

  In FIG. 8, the solid-state imaging device 10 </ b> B according to the third embodiment includes a plurality of photodiodes 11 as a plurality of light receiving units arranged so that their positions are periodically different, and image light on each of the plurality of photodiodes 11. And a microlens 122 for condensing the light.

  The plurality of photodiodes 11 are photoelectric conversion units that photoelectrically convert light, and are arranged so as to be periodically different in the row direction and the column direction in plan view, and have four photodiodes 11a having periodicity. ˜11d form one group for every four pixels in total in the row direction and the column direction in plan view.

  The microlens 122 includes an upper microlens 12A as a first microlens arranged for each photodiode 11, and a second microlens that covers the grouped four photodiodes 11a to 11d so as to cover the upper part thereof. And a lower layer microlens 12D.

  The lower-layer microlens 12D is provided between the photodiode 11 and the upper-layer microlens 12A. The upper-layer microlens 12A has a rectangular shape or a square shape in plan view, and its cross-sectional shape is convex upward (single-sided Convex lens shape (lower surface is flat), the lower microlens 12D is rectangular or square in plan view, and its cross-sectional shape is convex downward (single-sided convex) lens shape (upper surface is Plane). As described above, when the lower microlens 12D is convex downward, as in the case of the convex lower microlens 12B above the first embodiment, in accordance with the grouped photodiodes 11c and 11d, The light collected by the upper microlenses 12A can be bent toward each other (the light collected can be made closer to each other). Further, the refractive index of the transparent material of the lower layer microlens 12D is set larger than the refractive index of the transparent material in contact with the lens curved surface side of the lower layer microlens 12D.

As described above, according to the third embodiment, by forming the two types of microlenses 122 of the upper microlens 12A arranged for each pixel and the lower microlens 12D that covers the four pixels, the pixel In the solid-state imaging device 10B in which the arrangement of the photodiodes 11 as the light receiving portions in the cell 14 is periodically different in the row direction (horizontal direction) and the column direction (vertical direction), as in the case of the first embodiment, It is possible to improve the light receiving sensitivity of each pixel, reduce the variation in light collection for each pixel, and reduce color mixing.
(Embodiment 4)
In the first embodiment, the case of the upper-layer microlens 12A and the lower-layer microlens 12B having a convex lens shape has been described. However, in the third embodiment, the upper-layer microlens 12A having a convex lens shape, and A description will be given of the case of the lower microlens 12E that is convex downward and has a lens curved surface only at the outer peripheral portion.

  FIG. 9 is a longitudinal sectional view of the main part of the solid-state imaging device according to the fourth embodiment of the present invention, which is the same as that cut along the line BB ′ shown in FIG. 1, and image light is incident from directly above. It is a figure which shows the mode of condensing to each photodiode at the time. In addition, in FIG. 9, it respond | corresponds to FIG. 2 of the said Embodiment 1, and the same code | symbol is attached | subjected to the member which show | plays the same effect as the effect of FIG. In addition, regarding the state of light condensing on each photodiode when image light is incident from an oblique direction corresponding to FIG. 3 of the first embodiment, the lower microlens having a lens shape convex upward in FIG. Although 12B will be described later with reference to FIG. 9, it is only necessary to replace the lower microlens 12 </ b> E with a convex downward shape and a lens curved surface only at the outer peripheral portion.

  In FIG. 9, the solid-state imaging device 10 </ b> C according to the fourth embodiment includes a plurality of photodiodes 11 as a plurality of light receiving units arranged so that their positions are periodically different, and image light on each of the plurality of photodiodes 11. And a microlens 123 for condensing the light.

  The plurality of photodiodes 11 are photoelectric conversion units that photoelectrically convert light, and are arranged so as to be periodically different in the row direction and the column direction in plan view, and have four photodiodes 11a having periodicity. ˜11d form one group for every four pixels in total in the row direction and the column direction in plan view.

  The microlens 123 includes an upper microlens 12A serving as a first microlens arranged for each photodiode 11, and a second microlens that covers the upper portion of each of the grouped four photodiodes 11a to 11d. And a lower-layer microlens 12E.

  The lower-layer microlens 12E is provided between the photodiode 11 and the upper-layer microlens 12A. The upper-layer microlens 12A has a rectangular shape or a square shape in plan view, and its cross-sectional shape is convex upward (single-sided Convex lens shape (lower surface is flat), the lower microlens 12E is rectangular or square in plan view, and its cross-sectional shape is convex downward (single-sided convex) lens shape (upper surface is Plane). In the lower microlens 12E, a circular or elliptical outer peripheral portion 12Ea is formed in a convex lens curved surface shape, and a circular or elliptical central portion 12Eb is formed in a flat shape in a planar view. As described above, when the lower microlens 12E is convex downward and only the outer peripheral portion has a convex lens curved surface in a plan view, only the grouped photodiodes 11c and 11d (11c and 11d are shown). (All four of 11a to 11d) can be made to converge light by the upper microlens 12A on the outer peripheral portion of the outer peripheral portion by bending inward (condensing light toward each other). Further, the refractive index of the transparent material of the lower layer microlens 12E is set larger than the refractive index of the transparent material in contact with the lens curved surface side of the lower layer microlens 12E.

Therefore, according to the fourth embodiment, the two types of microlenses 123 are formed, that is, the upper microlens 12A disposed for each pixel and the lower microlens 12E that covers the upper portion of the pixel every four pixels. Thus, even in the solid-state imaging device 10C in which the arrangement of the photodiodes 11 as the light receiving portions in the pixel cell 14 is periodically different in the row direction (horizontal direction) and the column direction (vertical direction), as in the case of the first embodiment. Similarly, it is possible to improve the light receiving sensitivity of each pixel, reduce the variation in light collection for each pixel, and reduce color mixing. In this case, when manufacturing the large lower layer microlens 12E, since the central portion is a flat surface, the formation becomes easier.
(Embodiment 5)
In the first embodiment, the case where the upper microlens 12A having a convex lens shape is provided individually has been described, but in the fifth embodiment, four upper microlenses having a convex lens shape are provided. A description will be given of a case where the lenses are adjacent to each other as a group and approach each other beyond the peripheral edge of each lens, such as overlapping each other.

  10 is a longitudinal sectional view of a main part similar to the case where the solid-state imaging device according to Embodiment 5 of the present invention is cut along the line BB ′ shown in FIG. 1, and image light is incident from directly above. It is a figure which shows the mode of condensing to each photodiode at the time of being carried out. In addition, in FIG. 10, it respond | corresponds to FIG. 2 of the said Embodiment 1, and the same code | symbol is attached | subjected to the member which show | plays the same effect as the effect of FIG. Further, the state of light condensing on each photodiode when image light is incident from an oblique direction corresponding to FIG. 3 of the first embodiment is omitted here.

  In FIG. 10, the solid-state imaging device 10 </ b> D according to the fifth embodiment includes a plurality of photodiodes 11 as a plurality of light receiving units arranged so that positions are periodically different, and image light on each of the plurality of photodiodes 11. And a microlens 124 for condensing the light.

  The plurality of photodiodes 11 are photoelectric conversion units that photoelectrically convert light, and are arranged so as to be periodically different in the row direction and the column direction in plan view, and have four photodiodes 11a having periodicity. ˜11d form one group for every four pixels in total in the row direction and the column direction in plan view.

  The microlens 124 includes an upper microlens 12F as a first microlens arranged for each photodiode 11, and a second microlens that covers the grouped four photodiodes 11a to 11d so as to cover the upper part thereof. And a lower-layer microlens 12B.

  The upper microlens 12F is a part of the upper microlenses 12F adjacent to each other so that the incident light is condensed at the same position on each of the four photodiodes 11a to 11d for each corresponding group. (E.g., 2 out of 4) or all (e.g., all 4) approach each other beyond the peripheral edge of each lens (if the photodiodes are too close to each other, even if the lenses themselves overlap) In the case of further approach, lens portions that overlap each other are cut out and formed into adjacent lens shapes. The adjacent upper microlenses 12F are formed such that at least a part of the peripheral edge of the upper microlens 12F overlaps the adjacent upper microlens 12F. Further, the adjacent upper microlenses 12F are arranged such that the lens shapes obtained by cutting the overlapping lens portions are in contact with each other or separated by a predetermined gap. Further, the positions of the upper microlenses 12F are arranged differently according to the interval between the photodiodes 11.

  The lower-layer microlens 12B is provided between the photodiode 11 and the upper-layer microlens 12F, and the upper-layer microlens 12F has a rectangular shape or a square shape in plan view, and its cross-sectional shape is convex upward (one side Convex lens shape (lower surface is flat), the lower microlens 12B is rectangular or square in plan view, and its cross-sectional shape is convex upward (single-sided convex) lens shape (lower surface is Plane). As described above, the lower-layer microlens 12B can bend the light collected by the upper-layer microlenses 12F inward in accordance with the positions of the grouped photodiodes 11a to 11d (make the light-collected closer to each other). it can. Further, the refractive index of the transparent material of the lower layer microlens 12B is set to be larger than the refractive index of the transparent material in contact with the lens curved surface side of the lower layer microlens 12B.

  An example of a method for forming the upper microlens 12F will be briefly described.

  Conventionally, when microlenses are stacked on top of each other, they are pulled together after being solidified, causing the surface to deform or internal stress, causing cracks, or becoming unusable as a lens. In the fifth embodiment, when the arrangement interval of the upper microlenses 12F is reduced and overlapped with each other, the overlapping one upper microlens 12F is formed and solidified, and then the other upper microlens 12F is formed and solidified. Thus, the above-mentioned problem is solved by forming the upper microlenses 12F separately in two times (if the four upper microlenses 12F are grouped, form and harden them two by two). Even when one overlaps the other, the position of the adjacent upper-layer microlens 12F can be made arbitrarily close to facilitate the interval between the optical axes C. It can be constant.

  That is, the method of forming the upper microlens 12F includes a first step of forming the upper microlenses 12F that are not in contact with each other among the upper microlenses 12F and a contact with each other of the upper microlenses 12F that are not formed. The upper-layer microlens 12F in the non-overlapping position overlaps or comes into contact with the adjacent upper-layer microlens 12F that has already been formed in at least one of the row direction and the column direction (here, both the row direction and the column direction). The second step is repeated until there is no upper microlens 12F that is not formed.

  Further, as a method of forming the upper microlens 12F, in the case where the lens shapes obtained by cutting the overlapping lens portions are arranged with a minute gap by a predetermined gap, at least one of the row direction and the column direction ( In this case, there is a step of forming, as upper layer microlenses 12F adjacent to each other in both the row direction and the column direction), the lens shapes obtained by cutting the overlapping lens portions apart from each other by a predetermined gap.

  As described above, since the interval between the upper microlenses 12F can be arbitrarily reduced and set, for example, the center of each photodiode 11 is considered in consideration of the position of each photodiode 11, light receiving sensitivity, and shading characteristics. It can be easily arranged at the optimum position of the upper microlens 12F so that the position C1 coincides with the optical axis position C2 of the upper microlens 12F.

  Therefore, according to the fifth embodiment, the pixel cell is formed by forming the two types of microlenses 124, that is, the upper microlens 12F disposed for each pixel and the lower microlens 12B covering the four pixels. In the solid-state imaging device 10 </ b> D in which the arrangement of the photodiodes 11 as the light receiving portions in the 14 is periodically different in the row direction (horizontal direction) and the column direction (vertical direction), It is possible to improve the light receiving sensitivity of the pixels, reduce the variation in light collection for each pixel, and reduce color mixing.

  As described above, according to the first to fifth embodiments, the solid-state imaging device 10 (or the pixel device 14) having the pixel cells 14 in which the photodiodes 11 are biased so that the arrangement of the photodiodes 11 periodically differs in the row direction and the column direction. 10A, 10B, 10C, and 10D), the upper microlens 12A (or 12F) that groups four pixels having periodicity, is arranged for each pixel in each group, and collects image light. The lower layer microlens 12B (or 12C, 12D, 12E) for covering the four pixels and bending the light collected by the upper layer microlens 12A (or 12F) inward is provided. As a result, even when the pixel size is further reduced, the light receiving invalid area is reduced while condensing by the two upper and lower microlenses to improve the light receiving sensitivity of each pixel by the F value. Pixel characteristic deterioration can be suppressed.

  In addition, although the central portion of the light receiving region, the peripheral portion thereof, and the peripheral portion thereof have different colors of the three primary colors RGB (a state where R is mixed with G or B is mixed with G), the above embodiment is different. According to 1-4, since it can be easily and reliably focused on the central portion of the light receiving portion (each photodiode 11) in the central portion of the light receiving portion region and its peripheral portion, not only the light receiving sensitivity, Decrease in luminance shading characteristics and unevenness can be prevented. Therefore, complicated correction control is not required if this is solved by correction processing.

  In the first to fifth embodiments, the lower-layer microlenses 12B to 12D have a rectangular or square plan view shape, and the outer peripheral portion of the plan view shape and the central portion inside thereof are both curved lens surfaces. The lower-layer microlens 12E has a rectangular or square plan view shape. The outer peripheral portion of the plan view shape is a lens curved surface shape, and the central portion inside the outer peripheral portion of the plan view shape is a flat shape. Although the case has been described, the present invention is not limited thereto, and the lower layer microlens of the present invention may have a circular (including approximate circular) or elliptical planar view shape, and an outer peripheral portion of the planar view shape and Both inner central portions may have a curved lens surface shape, and the central portion may have a planar shape. In short, the lower-layer microlens of the present invention has a circle (including an approximate circle), an ellipse (including an approximate ellipse), a rectangle (including an approximate rectangle); at least one of the four corners is rounded. ) Or a square (including an approximate square; at least one corner is rounded or the like) in a plan view shape, and at least an outer peripheral portion of the plan view shape is formed in a lens curved surface shape.

  In the first to fifth embodiments, the plurality of photodiodes 11 as the plurality of light receiving units are provided in a matrix (two-dimensional) in the column direction and the row direction in plan view, and in the column direction and the row direction. Although the case where both are arranged so as to be periodically different has been described, the present invention is not limited to this, and the position of the light receiving portion (photodiode 11) in the pixel cell 14 is in any one of the row direction and the column direction. The present invention can also be applied to all solid-state imaging devices that are periodically different. In addition to the direction orthogonal to the column direction and the row direction, the plurality of photodiodes 11 are periodically arranged in one direction and at least one of the directions crossing the one direction in plan view. The present invention can also be applied to a case where they are arranged differently.

  Furthermore, in Embodiments 1 to 5, four pixels are grouped as a plurality of pixels having periodicity. However, the present invention is not limited to this, and a plurality of pixels having two or more pixels having periodicity are provided. The present invention can be applied to all the solid-state imaging devices.

  For example, as a predetermined number of light receiving portions (photodiodes 11) having periodicity, two pixels may be grouped in the column direction or the row direction in plan view. In this case, for each grouped two pixels, two light receiving portions (photodiodes 11) are formed evenly on the channel stop portion 13 side between adjacent pixels. Further, the lower microlens extending over the grouped two pixels is provided so that the optical axis C coincides with the channel stop portion 13 which is the center between the two light receiving portions (photodiodes 11) constituting the two pixels. ing.

  In addition, as described above, as a predetermined number of light receiving units (photodiodes 11) having periodicity, when a total of four pixels, each of two pixels in the column direction and the row direction in a plan view, are grouped, For each grouped four pixels, four light receiving portions (photodiodes 11) are formed evenly on the cross portion side of two channel stop portions 13 between adjacent pixels. Further, the lower-layer microlens extending over the grouped four pixels has an optical axis C at the center position of the cross portion of the two channel stop portions 13 which are the centers of the four light receiving portions (photodiodes 11) constituting the four pixels. Are provided to match.

  Furthermore, in the first to fifth embodiments, the cross-sectional shape of the upper microlens 12A (or 12F) as the first microlens is an upward convex lens shape, and the lower microlens 12B or 12C, 12D, 12E as the second microlens. In the above description, the case where the cross-sectional shape is a convex lens shape in the upper, lower, or upper and lower directions (a combination of the upper microlens 12F and the lower microlens 12B or 12C, 12D, and 12E may be used) is not limited thereto, and the upper microlens is not limited thereto. The cross-sectional shape of 12A (or 12F) may be a convex lens shape below or above and below, or a combination of any of these and the lower microlenses 12B or 12C, 12D, 12E.

  Furthermore, although the present invention has not been particularly described in the first to fifth embodiments, the N pixel unit (N) so that the positions of the photodiodes 11 and the upper microlenses 12A or 12F are periodically different from each other. Is an integer of 2 or more). Further, the positions of the photodiodes 11 and the upper microlenses 12A or 12F are arranged in a matrix, respectively, I pixels (I is an integer of 2 or more) in the row direction, and J pixels (J is The number of pixels is periodically arranged in units of K pixels (K = I × J). These N pixels or K pixels are grouped as a predetermined number of pixels.

  Furthermore, the present invention is not limited to the manufacturing method described in the first, second, and fifth embodiments, and may be applied to all solid-state imaging devices in which microlenses are formed by a known process technique such as photolithography and etching. Can do.

  Further, the present invention is not particularly described in the first to fifth embodiments, but can be applied to either a CCD image sensor or a CMOS image sensor.

  Further, although not particularly described in the first to fifth embodiments, next, for example, digital video using the solid-state imaging device 10 (or 10A, 10B, 10C, 10D) of the first to fourth embodiments as an imaging unit. An electronic information device having a digital camera such as a camera or a digital still camera, or an image input device such as an image input camera, a scanner, a facsimile, or a camera-equipped mobile phone device will be described. The electronic information device of the present invention is, for example, high-quality image data obtained by using any of the solid-state imaging devices 10 (or 10A, 10B, 10C, and 10D) of Embodiments 1 to 5 of the present invention as an imaging unit. A memory unit such as a recording medium for recording data after performing predetermined signal processing for recording, and a liquid crystal display device for displaying the image data on a display screen such as a liquid crystal display screen after performing predetermined signal processing for display A display unit, a communication unit such as a transmission / reception apparatus that performs communication processing after performing predetermined signal processing on the image data for communication, and an image output unit that prints (prints) and outputs (prints out) the image data. Have at least one of them.

  As mentioned above, although this invention has been illustrated using preferable Embodiment 1-5 of this invention, this invention should not be limited and limited to this Embodiment 1-5. It is understood that the scope of the present invention should be construed only by the claims. It is understood that those skilled in the art can implement an equivalent range based on the description of the present invention and the common general technical knowledge from the description of specific preferred embodiments 1 to 5 of the present invention. Patents, patent applications, and documents cited herein should be incorporated by reference in their entirety, as if the contents themselves were specifically described herein. Understood.

  The present invention relates to a solid-state imaging device such as a CCD-type image sensor or a CMOS-type image sensor provided with a microlens on a light-receiving unit, and a digital video camera and a digital device using this solid-state imaging device as an image input device in an imaging unit In the field of electronic information equipment such as a digital camera such as a still camera, an image input camera, a scanner, a facsimile, and a camera-equipped mobile phone device, even when the pixel size is further reduced, the upper and lower first microlenses and 2 Condensing light by a microlens and reducing the light reception invalid area to increase the light collection rate to improve the light reception sensitivity in each pixel, and when oblique light having a large angle is incident on the periphery of the light reception area, etc. It is possible to reduce variations in light collection rate and color mixing, and to suppress deterioration of the characteristics of each pixel. It can be improve the characteristics of the unit.

It is a top view which shows the example of a schematic principal part structure of the solid-state imaging device which concerns on Embodiment 1 of this invention. FIG. 2 is a cross-sectional view of a main part of a central portion of a light receiving region where light is incident from directly above, when the solid-state imaging device of FIG. 1 is cut along a B-B ′ line portion. FIG. 2 is a cross-sectional view of a main part of a peripheral portion of a light receiving region where light is incident from an oblique direction when the solid-state imaging device of FIG. 1 is cut along a B-B ′ line portion. It is a principal part longitudinal cross-sectional view for demonstrating the manufacturing process (the 1) of the manufacturing method of the solid-state imaging device of this Embodiment 1. FIG. FIG. 6 is a longitudinal sectional view of a main part for explaining a manufacturing process (No. 2) of the manufacturing method of the solid-state imaging device according to the first embodiment. It is a principal part longitudinal cross-sectional view for demonstrating the manufacturing process (the 3) of the manufacturing method of the solid-state imaging device of this Embodiment 1. FIG. It is a solid-state imaging device concerning Embodiment 2 of this invention, Comprising: It is principal part sectional drawing of the light-receiving region center part into which light injects from right above. It is a solid-state imaging device concerning Embodiment 2 of this invention, Comprising: It is principal part sectional drawing of the light-receiving region periphery part into which light injects from the diagonal direction. It is a principal part longitudinal cross-sectional view for demonstrating the manufacturing process (the 1) of the manufacturing method of the solid-state imaging device of this Embodiment 2. It is a principal part longitudinal cross-sectional view for demonstrating the manufacturing process (the 2) of the manufacturing method of the solid-state imaging device of this Embodiment 2. It is a principal part longitudinal cross-sectional view for demonstrating the manufacturing process (the 3) of the manufacturing method of the solid-state imaging device of this Embodiment 2. It is a principal part longitudinal cross-sectional view for demonstrating the manufacturing process (the 4) of the manufacturing method of the solid-state imaging device of this Embodiment 2. It is a principal part longitudinal cross-sectional view for demonstrating the manufacturing process (the 5) of the manufacturing method of the solid-state imaging device of this Embodiment 2. It is a principal part longitudinal cross-sectional view for demonstrating the manufacturing process (the 6) of the manufacturing method of the solid-state imaging device of this Embodiment 2. The solid-state imaging device according to Embodiment 3 of the present invention is a main part longitudinal cross-sectional view similar to that cut along the line BB ′ shown in FIG. 1, and each when image light is incident from directly above. It is a figure which shows the mode of condensing to a photodiode. About the solid-state imaging device which concerns on Embodiment 4 of this invention, it is the principal part longitudinal cross-sectional view similar to the case where it cut | disconnects by the BB 'line part shown in FIG. 1, and each when image light injects from right above. It is a figure which shows the mode of condensing to a photodiode. About the solid-state imaging device concerning Embodiment 5 of this invention, it is the principal part longitudinal cross-sectional view similar to the case where it cut | disconnects by the BB 'line | wire part shown in FIG. 1, and each when image light injects from right above. It is a figure which shows the mode of condensing to a photodiode. It is a top view which shows the example of a schematic principal part structure of the conventional solid-state imaging device. FIG. 12 is a cross-sectional view of a central portion of a light receiving region where light is incident from directly above, when the conventional solid-state imaging device of FIG. It is a top view which shows the example of a general principal part structure of the other conventional solid-state imaging device. FIG. 12 is a cross-sectional view of a peripheral portion of a light receiving region where light is incident from an oblique direction when the conventional solid-state imaging device of FIG.

Explanation of symbols

10, 10A, 10B, 10C, 10D Solid-state imaging device 11, 11a to 11d Photodiode (light receiving unit)
12, 121, 122, 123, 124 Microlens 12a Microlens material 12A, 12F Upper microlens 12B, 12C, 12D, 12E Lower microlens 13 Channel stop portion 14, 14a-14d Pixel cell 15 Color filter 16a Metal wiring (1 Layer)
16b Metal wiring (second layer)
16c Metal wiring (3rd layer)
17-19 Planarizing film 17a Uneven planarized film 7, 7a Resist film

Claims (30)

In a solid-state imaging device including a plurality of light receiving units arranged so that their positions are periodically different and a microlens for condensing light on each of the plurality of light receiving units,
A predetermined number of light receiving units having periodicity are grouped, and for each group, the microlens covers a first microlens arranged for each light receiving unit and above the predetermined number of light receiving units. A solid-state imaging device having a second microlens that straddles.   2. The solid-state imaging device according to claim 1, wherein the second microlens has a circular, elliptical, rectangular, or square planar view shape, and at least an outer peripheral portion of the planar view shape is formed in a lens curved surface shape. .   3. The solid-state imaging device according to claim 2, wherein the second microlens is formed such that a central portion inside an outer peripheral portion of the planar view shape is a curved lens surface or a planar shape.   The solid-state imaging device according to claim 1, wherein the second microlens is provided between the predetermined number of light receiving units and the first microlens.   The solid-state imaging device according to claim 1, wherein the first microlens is located in an upper layer than the second microlens.   The said 2nd micro lens becomes a structure which bends the condensing by each 1st micro lens arrange | positioned for every said light-receiving part inside every predetermined number of light-receiving parts which have the said periodicity. The solid-state imaging device according to any one of the above.   The solid-state imaging device according to claim 1, wherein a cross-sectional shape of the second microlens is a convex lens shape upward, downward, or vertically.   The solid-state imaging device according to claim 1, wherein a cross-sectional shape of the first microlens is a convex lens shape upward, downward, or vertically.   2. The solid-state imaging device according to claim 1, wherein the first microlens and the second microlens are arranged so that light is collected at a central portion of each light receiving unit.   2. The solid-state imaging device according to claim 1, wherein a metal wiring layer is provided between the light receiving portions and between the first microlens and the second microlens above the light receiving portions.   The solid-state imaging device according to claim 1, wherein the first microlens is provided above the color filter layer, and the second microlens is provided below the color filter layer.   2. The solid-state imaging device according to claim 1, wherein the plurality of light receiving units are arranged so as to be periodically different in at least one of a direction and a direction intersecting the one direction in a plan view.   The plurality of light receiving units are provided in a matrix in the column direction and the row direction in a plan view, and are arranged so as to be periodically different in at least one direction of the column direction and the row direction. Solid-state imaging device.   14. The solid according to claim 1, wherein the predetermined number of light-receiving portions having periodicity are a group of a total of four pixels of two pixels each in a column direction and a row direction in a plan view. Imaging device.   14. The solid-state imaging device according to claim 1, wherein the predetermined number of light receiving units having the periodicity are grouped in two pixels in a column direction or a row direction in a plan view.   The solid-state imaging device according to claim 14, wherein four of the light receiving portions are formed evenly on the cross portion side of the channel stop portion between adjacent pixels for every four pixels grouped.   The lower-layer microlens extending over the grouped four pixels is provided so that an optical axis thereof coincides with a cross portion of the channel stop portion that is a center of four light receiving portions constituting the four pixels. The solid-state imaging device described in 1.   The solid-state imaging device according to claim 15, wherein, for each of the two grouped pixels, two of the light receiving portions are formed equally on the channel stop portion side between adjacent pixels.   The lower-layer microlens straddling the grouped two pixels is provided so that an optical axis coincides with the channel stop portion which is a center between two light receiving portions constituting the two pixels. Solid-state imaging device.   One of the grouped first microlenses adjacent to each other so that the light incident on the first microlens is condensed through the second microlens at the same position on the corresponding light receiving unit. 2. The solid-state imaging device according to claim 1, wherein when a part or all of the lens parts are made to approach each other beyond the peripheral edge part of the lens, the lens parts that overlap each other are cut and adjacent to each other.   21. The solid-state imaging device according to claim 20, wherein the first microlenses adjacent to each other are formed such that at least a part of a peripheral portion of the first microlens overlaps the adjacent first microlens.   21. The solid-state imaging device according to claim 20, wherein the first microlenses adjacent to each other are arranged in contact with lens shapes obtained by cutting out the overlapping lens portions.   21. The solid-state imaging device according to claim 20, wherein the first microlenses adjacent to each other are arranged such that lens shapes obtained by cutting out the overlapping lens portions are separated by a predetermined gap.   The solid-state imaging device according to claim 20, wherein the position of the first microlens is arranged differently according to the interval between the light receiving portions.   21. The solid-state imaging device according to claim 1 or 20, wherein the light receiving unit and the first microlens are periodically arranged in units of N pixels (N is an integer of 2 or more) so that the positions of the light receiving unit and the first microlens are periodically different. .   The respective positions of the light receiving section and the first microlens are arranged in a matrix, and I pixels (I is an integer of 2 or more) in the row direction and J pixels (J is an integer of 2 or more) in the column direction. The solid-state imaging device according to claim 1, wherein the solid-state imaging device is periodically arranged in K pixel units (K = I × J).   21. The solid-state imaging device according to claim 1, wherein one output amplifier is shared by the predetermined number of light receiving units.   The solid-state imaging device according to claim 1, wherein the light receiving unit is a photoelectric conversion unit that photoelectrically converts light.   The solid-state imaging device according to claim 1 or 20, which is a CCD image sensor or a CMOS image sensor.   An electronic information device using the solid-state imaging device according to claim 1 for an imaging unit.

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