US20220059592A1 - Solid-state image sensor, method of manufacturing the same, and electronic device - Google Patents

Solid-state image sensor, method of manufacturing the same, and electronic device Download PDF

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US20220059592A1
US20220059592A1 US17/504,807 US202117504807A US2022059592A1 US 20220059592 A1 US20220059592 A1 US 20220059592A1 US 202117504807 A US202117504807 A US 202117504807A US 2022059592 A1 US2022059592 A1 US 2022059592A1
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pixel
electrode
photoelectric converting
image sensor
solid
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Yukio KANEDA
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Sony Semiconductor Solutions Corp
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    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14601—Structural or functional details thereof
    • H01L27/14603—Special geometry or disposition of pixel-elements, address-lines or gate-electrodes
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    • H01L27/144—Devices controlled by radiation
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    • H01L27/144—Devices controlled by radiation
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    • H01L27/144—Devices controlled by radiation
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    • H01L27/144—Devices controlled by radiation
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    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14643—Photodiode arrays; MOS imagers
    • H01L27/14645—Colour imagers
    • H01L27/14647—Multicolour imagers having a stacked pixel-element structure, e.g. npn, npnpn or MQW elements
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    • H01L27/144—Devices controlled by radiation
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    • H01L27/144—Devices controlled by radiation
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    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof
    • H04N25/10—Circuitry of solid-state image sensors [SSIS]; Control thereof for transforming different wavelengths into image signals
    • H04N25/11—Arrangement of colour filter arrays [CFA]; Filter mosaics
    • H04N25/13—Arrangement of colour filter arrays [CFA]; Filter mosaics characterised by the spectral characteristics of the filter elements
    • H04N25/134—Arrangement of colour filter arrays [CFA]; Filter mosaics characterised by the spectral characteristics of the filter elements based on three different wavelength filter elements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof
    • H04N25/70—SSIS architectures; Circuits associated therewith
    • H04N25/703—SSIS architectures incorporating pixels for producing signals other than image signals
    • H04N25/704—Pixels specially adapted for focusing, e.g. phase difference pixel sets
    • H04N5/36961—
    • H04N9/04557—
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K39/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic radiation-sensitive element covered by group H10K30/00
    • H10K39/30—Devices controlled by radiation
    • H10K39/32—Organic image sensors
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    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures
    • H01L27/14683—Processes or apparatus peculiar to the manufacture or treatment of these devices or parts thereof
    • H01L27/14692—Thin film technologies, e.g. amorphous, poly, micro- or nanocrystalline silicon
    • H01L27/307—

Definitions

  • the present disclosure relates to a solid-state image sensor, a method of manufacturing the same, and an electronic device, and especially relates to the solid-state image sensor capable of forming a more preferable pixel for detecting a focal point by using a photoelectric converting film, the method of manufacturing the same, and the electronic device.
  • a solid-state image sensor in which a semiconductor is used is mounted on many devices such as a digital camera, a video camera, a monitoring camera, a copying machine, and a fax machine.
  • CMOS image sensor manufactured by a complementary metal oxide semiconductor (CMOS) process together with a peripheral circuit is often used as the solid-state image sensor.
  • CMOS image sensor in which a method of using pixels for detecting a focal point with sensitivities asymmetrical with respect to a light incident angle is adopted as an automatic focusing function of a camera.
  • a photodiode in a pixel is divided into two and one of them with a smaller area is used for detecting a focal point as a method of realizing the pixel for detecting a focal point.
  • an image sensor in which an organic semiconductor and an inorganic compound semiconductor are used as a photoelectric converting film is developed.
  • This generally has an element structure including the photoelectric converting film and electrodes interposing the same from above and below in which at least one of the upper and lower electrodes is separated for each pixel.
  • a method of using the pixel for detecting a focal point is suggested.
  • Patent Document 2 an organic photoelectric converting element also having a color filter function arranged with the same optical path length as a silicon photodiode of a certain pixel is divided into two in the pixel and used as a pair, and according to this, light with different phase difference is detected and a focal point may be detected.
  • Patent Document 3 enables focal point detection by using a pair of pixels provided with a light shielding film on a light incident side in an organic photoelectric converting element for detecting phase difference.
  • a photoelectric converting film for detecting a focal point also serves as color filters in Bayer arrangement in the method of realizing in Patent Document 2, it is required to separate the photoelectric converting film for each pixel. Therefore, dark current due to separation of the photoelectric converting film might be deteriorated.
  • the present disclosure is achieved in view of such a condition, and an object thereof is to form a more preferable pixel for detecting a focal point by using the photoelectric converting film.
  • a solid-state image sensor is provided with a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel, and a second pixel including the photoelectric converting unit in which the separated electrode is formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size.
  • a method of manufacturing a solid-state image sensor forms a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel, and a second pixel including the photoelectric converting unit in which the separated electrode is formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size.
  • An electronic device including a solid-state image sensor including a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel, and a second pixel including the photoelectric converting unit in which the separated electrode is formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size.
  • a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel, and a second pixel including the photoelectric converting unit in which the separated electrode formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size are provided.
  • the solid-state image sensor and the electronic device may be independent devices or may be modules incorporated in other devices.
  • a more preferable pixel for detecting a focal point may be formed by using a photoelectric converting film.
  • the effect is not especially limited to the effects described herein; this may also any effect described in the present disclosure.
  • FIG. 1 is a view illustrating a schematic configuration of a solid-state image sensor according to the present disclosure.
  • FIG. 2 is a cross-sectional configuration diagram illustrating a cross-sectional configuration of a normal pixel.
  • FIG. 3 is a view illustrating a planar layout of a lower electrode of a first embodiment.
  • FIG. 4 is a cross-sectional configuration diagram taken along line Y 1 -Y 1 ′ in FIG. 3 .
  • FIG. 5 is a cross-sectional configuration diagram taken along line Y 2 -Y 2 ′ in FIG. 3 .
  • FIG. 6 is a view illustrating a planar layout of a lower electrode of a second embodiment.
  • FIG. 7 is a cross-sectional configuration diagram taken along line Y 11 -Y 11 ′ in FIG. 6 .
  • FIG. 8 is a view illustrating a planar layout of a third embodiment.
  • FIG. 9 is a cross-sectional configuration diagram taken along line X 11 -X 11 ′ in FIG. 8 .
  • FIG. 10 is a cross-sectional configuration diagram taken along line Y 21 -X 21 ′ in FIG. 8 .
  • FIG. 11 is a cross-sectional configuration diagram taken along line Y 22 -Y 22 ′ in FIG. 8 .
  • FIG. 12 is a view illustrating a variation of the third embodiment.
  • FIG. 13 is a view illustrating a variation of the third embodiment.
  • FIG. 14 is a cross-sectional configuration diagram of a pixel of a fourth embodiment.
  • FIG. 15 is a view illustrating a layout example of color filters.
  • FIG. 16 is a cross-sectional configuration diagram of a pixel of a fifth embodiment.
  • FIG. 17 is a cross-sectional configuration diagram of a pixel of a sixth embodiment.
  • FIGS. 18A to 18D are a view illustrating a method of manufacturing of the first embodiment.
  • FIGS. 19A to 19D are a view illustrating the method of manufacturing of the first embodiment.
  • FIGS. 20A to 20D are a view illustrating the method of manufacturing of the first embodiment.
  • FIGS. 21A to 21D are a view illustrating the method of manufacturing of the first embodiment.
  • FIGS. 22A and 22B are a view illustrating the method of manufacturing of the first embodiment.
  • FIGS. 23A and 23B are a view illustrating the method of manufacturing of the first embodiment.
  • FIGS. 24A and 24B are a view illustrating the method of manufacturing of the first embodiment.
  • FIG. 25A and 25B are a view illustrating the method of manufacturing of the first embodiment.
  • FIG. 26 is a block diagram illustrating a configuration example of an imaging device as an electronic device according to the present disclosure.
  • FIG. 1 illustrates a schematic configuration of a solid-state image sensor according to the present disclosure.
  • a solid-state image sensor 1 in FIG. 1 includes a pixel array unit 3 obtained by arranging pixels 2 in a two-dimensional manner to form a matrix on a semiconductor substrate 12 formed of silicon (Si), for example, as a semiconductor, and a peripheral circuit unit around the same.
  • the peripheral circuit unit includes a vertical driving circuit 4 , a column signal processing circuit 5 , a horizontal driving circuit 6 , an output circuit 7 , a control circuit 8 and the like.
  • the pixels 2 arranged in a two-dimensional manner to form a matrix in the pixel array unit 3 include a normal pixel 2 X which generates a signal for generating an image and a phase difference pixel 2 P which generates a signal for detecting a focal point as described later with reference to FIG. 3 and the like. There also is a case in which a dummy pixel 2 D is arranged adjacent to the phase difference pixel 2 P.
  • the vertical driving circuit 4 formed of a shift register selects pixel driving wiring 10 , supplies a pulse for driving the pixel 2 to the selected pixel driving wiring 10 , and drives the pixels 2 in a row unit. That is to say, the vertical driving circuit 4 sequentially selects to scan the pixels 2 in the pixel array unit 3 in a row unit in a vertical direction and supplies a pixel signal based on a signal charge generated according to a light receiving amount by a photoelectric converting unit of each pixel 2 to the column signal processing circuit 5 through a vertical signal line 9 .
  • the column signal processing circuit 5 arranged for each column of the pixels 2 performs signal processing such as noise removal on the signals output from the pixels 2 of one row for each pixel column.
  • the column signal processing circuit 5 performs the signal processing such as correlated double sampling (CDS) for removing a fixed pattern noise specific to the pixel and AD conversion.
  • CDS correlated double sampling
  • the horizontal driving circuit 6 formed of a shift register sequentially selects the column signal processing circuits 5 by sequentially outputting horizontal scanning pulses and outputs the pixel signal from each of the column signal processing circuits 5 to a horizontal signal line 11 .
  • the output circuit 7 performs predetermined signal processing on the signals sequentially supplied from the column signal processing circuits 5 through the horizontal signal line 11 to output through an output terminal 13 .
  • the output circuit 7 merely buffers, for example, or a case in which this performs black level adjustment, column variation correction, and various types of digital signal processing.
  • the control circuit 8 receives an input clock and data which designates an operation mode and the like, and also outputs data such as internal information of the solid-state image sensor 1 . That is, the control circuit 8 generates a clock signal and a control signal which serve as a reference for operation of the vertical driving circuit 4 , the column signal processing circuit 5 , the horizontal driving circuit 6 and the like on the basis of a vertical synchronization signal, a horizontal synchronization signal, and a master clock. The control circuit 8 then outputs the generated clock signal and control signal to the vertical driving circuit 4 , the column signal processing circuit 5 , the horizontal driving circuit 6 , and the like.
  • the solid-state image sensor 1 configured in the above-described manner is a so-called column AD type CMOS image sensor in which the column signal processing circuit 5 which performs the CDS processing and AD conversion processing is arranged for each pixel column.
  • a cross-sectional configuration of a normal pixel of a solid-state image sensor 1 is described with reference to FIG. 2 .
  • FIG. 2 is a view illustrating the cross-sectional configuration of a normal pixel 2 X of the solid-state image sensor 1 in FIG. 1 .
  • Photodiodes PD 1 and PD 2 by PN junction are formed in a depth direction by forming second conductivity type (for example, N-type) semiconductor regions 42 and 43 so as to be stacked in the depth direction in a first conductivity type (for example, P-type) semiconductor region 41 of a semiconductor substrate 12 .
  • the photodiode PD 1 including the semiconductor region 42 as a charge accumulation region is an inorganic photoelectric converting unit which receives blue light to perform photoelectric conversion
  • the photodiode PD 2 including the semiconductor region 43 as a charge accumulation region is an inorganic photoelectric converting unit which receives red light to perform the photoelectric conversion.
  • a plurality of pixel transistors which reads the charges accumulated in the photodiodes PD 1 and PD 2 and a multi-layer wiring layer 44 formed of a plurality of wiring layers and an interlayer insulating film are formed on a surface side (lower side in the drawing) of the semiconductor substrate 12 . Meanwhile, the multi-layer wiring layer 44 is not illustrated in detail in FIG. 2 .
  • a plurality of pixel transistors is formed of four MOS transistors which are a transfer transistor, a selection transistor, a reset transistor, and an amplification transistor, for example.
  • a conductive plug 46 for extracting the charge obtained by the photoelectric conversion by a photoelectric converting film 52 to be described later to a side of the multi-layer wiring layer 44 is formed on the semiconductor substrate 12 so as to penetrate (the semiconductor region 41 of) the semiconductor substrate 12 .
  • An SiO2 or SiN insulating film 47 is formed on an outer periphery of the conductive plug 46 so as to inhibit short-circuit with the semiconductor region 41 .
  • the conductive plug 46 is connected to a floating diffusion unit (FD unit) 49 formed of a second conductivity type (for example, N-type) semiconductor region in the semiconductor substrate 12 by means of metal wiring 48 formed in the multi-layer wiring layer 44 .
  • the FD unit 49 is a region in which the charge obtained by the photoelectric conversion by the photoelectric converting film 52 is temporarily held before being read.
  • the charge held in the FD unit 49 is output to the column signal processing circuit 5 on a subsequent stage through the amplification transistor and the like as is the case with the charges generated by the photodiodes PD 1 and PD 2 .
  • the transfer transistor required in the photodiodes PD 1 and PD 2 is not required when the charge generated by the photoelectric converting film 52 is output as a signal. Therefore, the photoelectric conversion using the photoelectric converting film 52 has an advantage that light receiving areas of the photodiodes PD 1 and PD 2 are not narrowed.
  • a transparent insulating film 51 formed of two or three layers of a hafnium oxide (HfO2) film and a silicon oxide film is formed, for example, on an interface on a rear surface side (upper side in the drawing) of the semiconductor substrate 12 .
  • HfO2 hafnium oxide
  • the photoelectric converting film 52 is arranged above the transparent insulating film 51 so as to be interposed between a lower electrode 53 a below the same and an upper electrode 53 b above the same. Out of a region in which the photoelectric converting film 52 is formed, a region interposed between the lower electrode 53 a and the upper electrode 53 b is the region in which incident light is subjected to the photoelectric conversion; the photoelectric converting film 52 , the lower electrode 53 a , and the upper electrode 53 b form a photoelectric converting unit 61 .
  • the photoelectric converting film 52 is formed of an organic photoelectric converting material containing a rhodamine dye, a merocyanine dye, or quinacridone, for example.
  • the lower electrode 53 a and the upper electrode 53 b are formed of an indium tin oxide (ITO) film, an indium zinc oxide film and the like, for example.
  • the photoelectric converting film 52 is a film which performs the photoelectric conversion on red wavelength light
  • an organic photoelectric converting material containing a phthalocyanine dye may be used, for example.
  • an organic photoelectric converting material containing a coumarin dye, tris(8-hydroxyquinoline) aluminum (Alq3), the merocyanine dye and the like may be used.
  • the lower electrode 53 a is formed for each pixel and is connected to the conductive plug 46 of the semiconductor substrate 12 by means of metal wiring 54 penetrating the transparent insulating film 51 .
  • the metal wiring 54 formed of materials such as tungsten (W), aluminum (Al), and copper (Cu) is also formed in a planar direction at predetermined depth of the transparent insulating film 51 and also serves as an interpixel light shielding film 55 which inhibits the light from entering an adjacent pixel.
  • a high refractive index layer 56 is formed of an inorganic film such as a silicon nitride film (SiN), silicon oxynitride film (SiON), and silicon carbide (SiC) on an upper surface of the upper electrode 53 b .
  • an on-chip lens 57 is formed above the high refractive index layer 56 .
  • the silicon nitride film (SiN) or a resin material such as a styrene resin, an acrylic resin, a styrene acrylic copolymer resin, or a siloxane resin, for example, is used as a material of the on-chip lens 57 .
  • FIG. 2 three normal pixels 2 X configured in the above-described manner are arranged side by side.
  • the solid-state image sensor 1 in which the normal pixels 2 X formed in this manner are arranged in a two-dimensional manner is a rear surface irradiation type CMOS solid-state image sensor in which the light enters from a rear surface side on an opposite side of the surface side of the semiconductor substrate 12 on which the multi-layer wiring layer 44 is formed.
  • the solid-state image sensor 1 is a longitudinal direction spectral solid-state image sensor which performs the photoelectric conversion by the photoelectric converting film 52 formed above the semiconductor substrate (silicon layer) 12 on the green light and performs the photoelectric conversion by the photodiodes PD 1 and PD 2 in the semiconductor substrate 12 on the blue light and red light.
  • FIG. 3 is a view illustrating a planar layout of the lower electrode in the pixel array unit 3 .
  • the lower electrode 53 a is formed for each pixel.
  • the cross-sectional view illustrated in FIG. 2 corresponds a cross-sectional view of a portion in which the three normal pixels 2 X are arranged in a horizontal direction indicated by line X 1 -X 1 ′ in FIG. 3 , for example.
  • the pixels 2 arranged in a two-dimensional manner in the pixel array unit 3 include the pixel 2 including a lower electrode 53 c a planar size of which is made smaller than that of the lower electrode 53 a of the normal pixel 2 X and the pixel 2 including a lower electrode 53 d enlarged to a region which is vacant due to a decrease in size of the lower electrode 53 c.
  • the pixel 2 including the downsized lower electrode 53 c is the phase difference pixel 2 P which generates a signal for detecting a focal point and the pixel 2 including the enlarged lower electrode 53 d is a dummy pixel 2 D arranged adjacent to the phase difference pixel 2 P.
  • a pair (two) of the phase difference pixels 2 P configured such that sensitivities are asymmetrical with respect to a light incident angle is arranged in the pixel array unit 3 .
  • the two phase difference pixels 2 P which form a pair are represented as a type A phase difference pixel 2 P A and a type B phase difference pixel 2 P B .
  • the dummy pixel 2 D arranged adjacent to the phase difference pixel 2 P A is represented as a dummy pixel 2 D A and the dummy pixel 2 D arranged adjacent to the phase difference pixel 2 P B is represented as a dummy pixel 2 D B .
  • the phase difference pixel 2 P A is the pixel in which the lower electrode 53 c is formed so as to receive light only by a left side in the pixel as compared to the normal pixel 2 X
  • the phase difference pixel 2 P B is the pixel in which the lower electrode 53 c is formed only on a right side in the pixel such that a photoelectric conversion region is symmetrical to that in the phase difference pixel 2 P A .
  • a pair of the phase difference pixel 2 P A and the dummy pixel 2 D A and a pair of the phase difference pixel 2 P B and the dummy pixel 2 D B are arranged so as to be adjacent in a longitudinal direction (vertical direction) in the example in FIG. 3 , they are not necessarily arranged so as to be adjacent in the longitudinal direction.
  • the pair of the phase difference pixel 2 P A and the dummy pixel 2 D A and the pair of the phase difference pixel 2 P B and the dummy pixel 2 D B may be arranged with one or more pixels interposed therebetween or arranged so as to be adjacent in a lateral direction (horizontal direction).
  • the lower electrodes 53 c of the phase difference pixels 2 P A and 2 P B are downsized in the lateral direction (horizontal direction) as compared to the lower electrode 53 a in the normal pixel 2 X in the example in FIG. 3 , they may also be downsized in the longitudinal direction (vertical direction).
  • the phase difference pixel 2 P A and the dummy pixel 2 D A are arranged so as to be adjacent in the longitudinal direction and the phase difference pixel 2 P B and the dummy pixel 2 D B are also arranged so as to be adjacent in the longitudinal direction.
  • the pair of the phase difference pixels 2 P A and 2 P B including the lower electrodes 53 c downsized in the lateral direction and the pair of the phase difference pixels 2 P A and 2 P B including the lower electrodes 53 c downsized in the longitudinal direction may be mixed in the pixel array unit 3 .
  • Displacement in image occurs between the pixel signal from the phase difference pixel 2 P A and the pixel signal from the phase difference pixel 2 P B because the lower electrodes 53 c are formed in different positions. It is possible to realize automatic focusing by calculating a defocusing amount by calculating a phase displacement amount from the displacement in image to adjust (move) an imaging lens.
  • FIG. 4 illustrates a cross-sectional configuration taken along line Y 1 -Y 1 ′ in FIG. 3 in which one normal pixel 2 X and the pair of the phase difference pixel 2 P A and the dummy pixel 2 D A are included.
  • FIG. 5 illustrates a cross-sectional configuration taken along line Y 2 -Y 2 ′ in FIG. 3 in which one normal pixel 2 X and the pair of the phase difference pixel 2 P B and the dummy pixel 2 D B are included.
  • the lower electrode 53 c of the phase difference pixel 2 P ( 2 P A or 2 P B ) is downsized in the lateral direction (horizontal direction) as compared to the lower electrode 53 a of the normal pixel 2 X and the lower electrode 53 d of the dummy pixel 2 D ( 2 D A or 2 D B ) is extended to a region which is vacant due to downsizing to be formed.
  • an interval in the planar direction between the lower electrode 53 c of the phase difference pixel 2 P and the lower electrode 53 d of the dummy pixel 2 D is set to be the same as the interval between the lower electrodes 53 a of two adjacent normal pixels 2 X, they are not necessarily the same.
  • phase difference pixel 2 P and the dummy pixel 2 D the configuration other than the lower electrodes 53 c and 53 d is similar to that of the normal pixel 2 X. Therefore, B signals and R signals generated by the photodiodes PD 1 and PD 2 of the phase difference pixel 2 P and the dummy pixel 2 D may be utilized as the signals for generating an image.
  • a G signal generated by the photoelectric converting unit 61 that is to say, the photoelectric converting film 52 , the upper electrode 53 b , and the lower electrode 53 c of the phase difference pixel 2 P is output to the FD unit 49 through the metal wiring 54 and the conductive plug 46 to be utilized as the signal for detecting a focal point.
  • the G signal for generating an image of the phase difference pixel 2 P is calculated by interpolation from the G signals of a plurality of normal pixels 2 X around the phase difference pixel 2 P, for example.
  • the G signal generated by the photoelectric converting unit 61 that is to say, the photoelectric converting film 52 , the upper electrode 53 b , and the lower electrode 53 d of the dummy pixel 2 D is output to the FD unit 49 through the metal wiring 54 and the conductive plug 46 , but this is discharged without being utilized.
  • the G signal for generating an image of the dummy pixel 2 D is also calculated by the interpolation from the G signals of a plurality of normal pixels 2 X around the dummy pixel 2 D, for example.
  • the phase difference pixel 2 P configured in the above-described manner, it is not required to form a light shielding film on an upper surface of the photoelectric converting film 52 for each color, so that it is possible to realize the phase difference pixel while avoiding an increase in the number of steps for forming the light shielding film. Also, it is not required to separate the photoelectric converting film 52 between the pixels, so that it is possible to inhibit dark current generated when the photoelectric converting film 52 is separated between the pixels.
  • phase difference pixel 2 P for detecting a focal point by using the photoelectric converting film 52 formed on an outer side of the semiconductor substrate 12 .
  • the G signal output from the phase difference pixel 2 P is used as the signal for detecting a focal point; however, it is possible to arbitrarily select the color of the light on which the photoelectric conversion is performed by the photoelectric converting film 52 . That is to say, in the longitudinal direction spectral solid-state image sensor, it is possible to appropriately determine the color of the light on which the photoelectric conversion is performed by the photoelectric converting film 52 formed above the semiconductor substrate 12 and the colors of the light on which the photoelectric conversion is performed by the photodiodes PD 1 and PD 2 in the semiconductor substrate 12 .
  • FIG. 6 is a view illustrating a planar layout of a lower electrode in a pixel array unit 3 .
  • phase difference pixels 2 P A and 2 P B are arranged in a linear manner with a dummy pixel 2 D interposed therebetween. That is to say, the phase difference pixel 2 P A , the dummy pixel 2 D, and the phase difference pixel 2 P B are arranged in the pixel array unit 3 in this order. Therefore, the dummy pixel 2 D is arranged adjacent to the phase difference pixels 2 P A and 2 P B ; this serves as a dummy pixel 2 D A arranged adjacent to the phase difference pixel 2 P A and a dummy pixel 2 D B arranged adjacent to the phase difference pixel 2 P B .
  • Such dummy pixel 2 D is represented as a dummy pixel 2 D AB .
  • the phase difference pixel 2 P A includes a lower electrode 53 c formed so as to receive light only on a left side in the pixel as in the first embodiment.
  • the phase difference pixel 2 P B includes the lower electrode 53 c only on a right side in the pixel such that a photoelectric conversion region is symmetrical to that of the phase difference pixel 2 P A .
  • a lower electrode 53 d of the dummy pixel 2 D AB arranged in the center is extended to regions of the phase difference pixels 2 P A and 2 P B which are vacant due to downsizing of the lower electrodes 53 c to be formed.
  • the lower electrode 53 d of the dummy pixel 2 D AB is formed so as to extend to sides of the phase difference pixels 2 P A and 2 P B to lie across three pixels.
  • phase difference pixel 2 P A , the dummy pixel 2 D, and the phase difference pixel 2 P B are arranged in a linear manner in a horizontal direction in this order in the example in FIG. 6 , it is also possible to configure such that they are arranged in a linear manner in a vertical direction.
  • FIG. 7 illustrates a cross-sectional configuration taken along line Y 11 -Y 11 ′ in FIG. 6 including the phase difference pixel 2 P A , the dummy pixel 2 D AB , and the phase difference pixel 2 P B .
  • the lower electrodes 53 c of the phase difference pixels 2 P A and 2 P B are downsized in a lateral direction (horizontal direction) as compared to a lower electrode 53 a of a normal pixel 2 X and the lower electrode 53 d of the dummy pixel 2 D AB is extended to the regions which are vacant due to the downsizing to be formed.
  • phase difference pixels 2 P A and 2 P B a charge generated in a region interposed between an upper electrode 53 b and the lower electrode 53 c out of a region of a photoelectric converting film 52 is accumulated in a FD unit 49 .
  • Positions in which the lower electrodes 53 c are formed in the phase difference pixels 2 P A and 2 P B are symmetrical to each other. Displacement in image occurs between pixel signals from the phase difference pixels 2 P A and 2 P B because the lower electrodes 53 c are formed in different positions. It is possible to realize automatic focusing by calculating a defocusing amount by calculating a phase displacement amount from the displacement in image to adjust (move) an imaging lens.
  • phase difference pixel 2 P configured in the above-described manner, it is not required to form a light shielding film on an upper surface of the photoelectric converting film 52 for each color, so that it is possible to realize the phase difference pixel while avoiding an increase in the number of steps for forming the light shielding film. Also, it is not required to separate the photoelectric converting film 52 between the pixels, so that it is possible to inhibit dark current generated when the photoelectric converting film 52 is separated between the pixels.
  • phase difference pixel 2 P for detecting a focal point by using the photoelectric converting film 52 formed on an outer side of the semiconductor substrate 12 .
  • FIG. 8 is a view illustrating a planar layout of a lower electrode in a pixel array unit 3 .
  • FIG. 8 a broken line indicating a boundary of each pixel 2 illustrated in FIGS. 3 and 6 is omitted in order to make the drawing more visible.
  • an element separating electrode 81 which separates pixels (elements) is formed between lower electrodes 53 a and 53 c adjacent to each other.
  • a material similar to that of the lower electrodes 53 a and 53 c such as an indium tin oxide (ITO) film and an indium zinc oxide film, for example, may be used as a material of the element separating electrode 81 .
  • the element separating electrode 81 is formed between the lower electrodes 53 a and 53 c adjacent to each other in a vertical direction and in a horizontal direction, so that this is formed into a lattice shape as illustrated in FIG. 8 .
  • Predetermined fixed potential is applied to the element separating electrode 81 . According to this, it is possible to prevent capacity coupling between the adjacent pixels and inhibit an after image by collecting a charge generated between the pixels.
  • a phase difference pixel 2 P A includes the lower electrode 53 c formed so as to receive light only on a left side in the pixel as in the first embodiment.
  • the phase difference pixel 2 P B includes the lower electrode 53 c only on a right side in the pixel such that a photoelectric conversion region is symmetrical to that of the phase difference pixel 2 P A .
  • the element separating electrode 81 is formed in a region which is vacant due to downsizing of the lower electrode 53 c of the phase difference pixel 2 P A so as to be extended from a pixel boundary line.
  • the element separating electrode 81 is formed also in a region which is vacant due to the downsizing of the lower electrode 53 c of the phase difference pixel 2 P B so as to be extended from the pixel boundary line. That is to say, each of the phase difference pixels 2 P A and 2 P B has a configuration in which the element separating electrode 81 adjacent thereto is extended to the region which is vacant due to the downsized lower electrode 53 c to be formed.
  • Positions in which the lower electrodes 53 c are formed in the phase difference pixels 2 P A and 2 P B configured in the above-described manner are symmetrical to each other. Displacement in image occurs between pixel signals from the phase difference pixels 2 P A and 2 P B because the lower electrodes 53 c are formed in different positions. It is possible to realize automatic focusing by calculating a defocusing amount by calculating a phase displacement amount from the displacement in image to adjust (move) an imaging lens.
  • the lower electrodes 53 c of the phase difference pixels 2 P A and 2 P B are downsized in a lateral direction (horizontal direction) as compared to the lower electrode 53 a of a normal pixel 2 X in the example in FIG. 8 , they may also be downsized in a longitudinal direction (vertical direction).
  • the element separating electrode 81 which separates the upper and lower lower electrodes 53 a and 53 c is formed so as to be extended in the longitudinal direction in each of the phase difference pixels 2 P A and 2 P B .
  • FIG. 9 is a cross-sectional configuration diagram taken along line X 11 -X 11 ′ in FIG. 8 including two normal pixels 2 X.
  • FIG. 10 is a cross-sectional configuration diagram taken along line Y 21 -Y 21 ′ in FIG. 8 including one normal pixel 2 X and one phase difference pixel 2 P A .
  • FIG. 11 is a cross-sectional configuration diagram taken along line Y 22 -Y 22 ′ in FIG. 8 including one normal pixel 2 X and one phase difference pixel 2 P B .
  • the element separating electrode 81 is formed in a position on the pixel boundary in a planar direction and in the same position as that of the lower electrode 53 a in a depth direction.
  • the element separating electrode 81 is connected to metal wiring 82 formed below the same and predetermined fixed potential is applied to the element separating electrode 81 through the metal wiring 82 .
  • the element separating electrode 81 is formed in the region which is vacant due to the downsizing of the lower electrode 53 c of the phase difference pixel 2 P A so as to be extended from the pixel boundary line.
  • the element separating electrode 81 is formed in the region which is vacant due to the downsizing of the lower electrode 53 c of the phase difference pixel 2 P B so as to be extended from the pixel boundary line.
  • the extended element separating electrode 81 is connected to the metal wiring 82 formed below the same and predetermined fixed potential is applied to the element separating electrode 81 also in FIGS. 10 and 11 as in FIG. 9 .
  • the charge generated by a photoelectric converting film 52 interposed between the extended element separating electrode 81 and an upper electrode 53 b is not connected to the FD unit 49 and is not extracted as a signal.
  • phase difference pixel 2 P configured in the above-described manner, it is not required to form a light shielding film on an upper surface of the photoelectric converting film 52 for each color, so that it is possible to realize the phase difference pixel while avoiding an increase in the number of steps for forming the light shielding film. Also, it is not required to separate the photoelectric converting film 52 between the pixels, so that it is possible to inhibit dark current generated when the photoelectric converting film 52 is separated between the pixels.
  • phase difference pixel 2 P for detecting a focal point by using the photoelectric converting film 52 formed on an outer side of the semiconductor substrate 12 .
  • a layout is such that a normal pixel 2 X is arranged adjacent to a phase difference pixel 2 P A or 2 P B in a vertical direction and in a horizontal direction in an example illustrated in FIG. 8
  • the layout may also be such that the phase difference pixels 2 P A and 2 P B are arranged adjacent to each other in the vertical direction or in the horizontal direction as illustrated in FIG. 12 .
  • an element separating electrode 81 is extended on the assumption that the element separating electrode 81 is formed into a lattice shape on a pixel boundary in the vertical direction and in the horizontal direction in the description above, the element separating electrode 81 in the lattice shape may be omitted as illustrated in FIG. 13 . Also, it is of course possible to configure such that the element separating electrode 81 in the lattice shape is omitted from the layout illustrated in FIG. 8 and only an element separating electrode 83 having an island shape is provided. In this case, predetermined fixed potential is applied only to the element separating electrode 83 having the island shape. Furthermore, a shape may be such that not an entire element separating electrode 81 in the lattice shape is omitted but only a part of the element separating electrode 81 in the lattice shape is omitted to form a H shape, for example.
  • difference between the element separating electrode 83 in the island shape illustrated in FIG. 13 and a lower electrode 53 c in an island shape of a dummy pixel 2 D AB of the second embodiment illustrated in FIG. 6 is that the former is connected to metal wiring 82 which supplies predetermined fixed potential and the latter is connected to a FD unit 49 which accumulates a charge.
  • the element separating electrode 83 in the island shape illustrated in FIG. 13 may also have an isolated pattern without being connected to the metal wiring 82 formed below the same. Alternatively, it is also possible to configure such that the element separating electrode 83 in the island shape in FIG. 13 is not connected to the metal wiring 82 formed below the same but connected to the FD unit 49 to accumulate the charge to discharge.
  • each pixel 2 receives light of all wavelengths of red (R), green (G), and blue (B) by a photoelectric converting unit 61 and photodiodes PD 1 and PD 2 ; however, fourth to sixth embodiments to be described hereinafter are different in that each pixel 2 receives only light of any of the wavelengths of red (R), green (G), and blue (B).
  • FIG. 14 being a cross-sectional configuration diagram of the pixel 2 of the fourth embodiment illustrates a cross-sectional configuration of a portion corresponding to line Y 1 -Y 1 ′ in FIG. 3 in which one normal pixel 2 X and a pair of a phase difference pixel 2 P A and a dummy pixel 2 D A are included.
  • FIG. 14 Comparing the cross-sectional configuration of the first embodiment illustrated in FIG. 4 with the cross-sectional configuration of the fourth embodiment in FIG. 14 being the cross-sectional configuration diagrams taken along line Y 1 -Y 1 ′ in FIG. 3 , in FIG. 14 , a photoelectric converting film 52 which performs photoelectric conversion on green wavelength light in FIG. 4 is replaced with a photoelectric converting film 91 which performs the photoelectric conversion on the light of all the wavelengths of red (R), green (G), and blue (B). Also, the photodiode PD 1 which receives the blue light and the photodiode PD 2 which receives the red light are not provided in a semiconductor substrate 12 .
  • a color filter 92 which transmits the light of the wavelength of red (R), green (G), or blue (B) is newly provided between a high refractive index layer 56 and an on-chip lens 57 .
  • each pixel 2 receives only the light of any of the wavelengths of red (R), green (G), and blue (B).
  • a rear surface irradiation type configuration in which the photoelectric converting unit 61 and the on-chip lens 57 are formed on a rear surface side opposite to a surface side on which a multi-layer wiring layer 44 is formed is adopted in the first embodiment illustrated in FIG. 4 .
  • a surface irradiation type configuration in which the photoelectric converting unit 61 and the on-chip lens 57 are formed on the surface side of the semiconductor substrate 12 , the side on which the multi-layer wiring layer 44 is formed is adopted.
  • the multi-layer wiring layer 44 is formed on the surface side of the semiconductor substrate 12 and a transparent insulating film 51 , a lower electrode 53 a , the photoelectric converting film 91 , an upper electrode 53 b , the high refractive index layer 56 and the like are formed on an upper surface of the multi-layer wiring layer 44 .
  • the FD unit 49 which holds the charge generated by a photoelectric converting film 52 is also formed on the surface side of the semiconductor substrate 12 . Therefore, in the fourth embodiment, a conductive plug 46 and an insulating film 47 for extracting the charge generated by the photoelectric converting film 91 to the rear surface side of the semiconductor substrate 12 are not provided.
  • FIG. 15 is a view illustrating a layout example of the color filters 92 illustrated so as to correspond to the planar layout in FIG. 3 .
  • the color filters 92 are arranged in Bayer arrangement, for example, as illustrated in FIG. 15 .
  • phase difference pixel 2 P A and a phase difference pixel 2 P B are the pixels which receive a green (Gr, Gb) wavelength
  • the dummy pixel 2 D A is the pixel which receives a red (R) wavelength
  • a dummy pixel 2 D B is the pixel which receives a blue (B) wavelength in the example in FIG. 15
  • the wavelengths (colors) of the light received by the phase difference pixel 2 P and the dummy pixel 2 D are not limited to this example.
  • it is desirable that the wavelength of the light received by the phase difference pixel 2 P A and the wavelength of the light received by the phase difference pixel 2 P B are the same.
  • phase difference pixels 2 P A and 2 P B white pixels which receive the light of all the wavelengths by using a material which transmits all the wavelengths in place of the color filter 92 .
  • the material used in place of the color filter 92 may be the same material as that of the high refractive index layer 56 and the on-chip lens 57 , for example.
  • FIG. 16 being a cross-sectional configuration diagram of a pixel 2 of the fifth embodiment illustrates a cross-sectional configuration of a portion corresponding to line Y 11 -Y 11 ′ in FIG. 6 in which phase difference pixels 2 P A and 2 P B and a dummy pixel 2 D AB interposed therebetween are included.
  • a wavelength of light received by each pixel 2 is configured so as to be similar to that of the fourth embodiment described with reference to FIG. 14 and an arrangement configuration of lower electrodes 53 c and 53 d is similar to that of the second embodiment described with reference to FIG. 7 .
  • color filters 92 in Bayer arrangement is formed between a high refractive index layer 56 and an on-chip lens 57 and a photoelectric converting film 91 which performs photoelectric conversion on light of all the wavelengths of red (R), green (G), and blue (B) is formed between the lower electrode 53 c or 53 d and an upper electrode 53 b .
  • a photoelectric converting unit 61 of each pixel 2 receives only the light of any of the wavelengths of red (R), green (G), and blue (B).
  • phase difference pixels 2 P A and 2 P B are arranged in a linear manner with the dummy pixel 2 D AB interposed therebetween. Then, the lower electrode 53 d of the dummy pixel 2 D AB arranged in the center is extended to regions which are vacant due to downsizing of the lower electrodes 53 c of the phase difference pixels 2 P A and 2 P B to be formed.
  • a pixel structure of the fifth embodiment is a surface irradiation type structure in which the photoelectric converting unit 61 and the on-chip lens 57 are formed on a surface side of a semiconductor substrate 12 , the side on which a multi-layer wiring layer 44 is formed.
  • FIG. 17 being a cross-sectional configuration diagram of a pixel 2 of the sixth embodiment illustrates a cross-sectional configuration of a portion corresponding to line Y 21 -Y 21 ′ in FIG. 8 in which one normal pixel 2 X and one phase difference pixel 2 P A are included.
  • a wavelength of light received by each pixel 2 is configured so as to be similar to that of the fourth embodiment described with reference to FIG. 14 and an arrangement configuration of a lower electrode 53 c and an element separating electrode 81 is similar to that of the third embodiment described with reference to FIG. 10 .
  • color filters 92 in Bayer arrangement are formed between a high refractive index layer 56 and an on-chip lens 57 and a photoelectric converting film 91 which performs photoelectric conversion on light of all the wavelengths of red (R), green (G), and blue (B) is formed between a lower electrode 53 a or 53 c and an upper electrode 53 b .
  • a photoelectric converting unit 61 of each pixel 2 receives only the light of any of the wavelengths of red (R), green (G), and blue (B).
  • the element separating electrode 81 is formed between the phase difference pixel 2 P A and the normal pixel 2 X, and the element separating electrode 81 is formed in a region which is vacant due to downsizing of the lower electrode 53 c of the phase difference pixel 2 P A so as to be extended from a pixel boundary line as illustrated in FIG. 17 .
  • the element separating electrode 81 is formed in a position on the pixel boundary. Also, in a portion in which a phase difference pixel 2 P B and the normal pixel 2 X are adjacent to each other, as in FIG. 11 , the element separating electrode 81 is formed in a region which is vacant due to the downsizing of the lower electrode 53 c of the phase difference pixel 2 P B so as to be extended from the pixel boundary line.
  • a pixel structure of the sixth embodiment is a surface irradiation type structure in which the photoelectric converting unit 61 and the on-chip lens 57 are formed on a surface side of a semiconductor substrate 12 , the side on which a multi-layer wiring layer 44 is formed.
  • positions in which the lower electrodes 53 c are formed in the phase difference pixels 2 P A and 2 P B are symmetrical with each other. Displacement in image occurs between pixel signals from the phase difference pixels 2 P A and 2 P B because the lower electrodes 53 c are formed in different positions. It is possible to realize automatic focusing by calculating a defocusing amount by calculating a phase displacement amount from the displacement in image to adjust (move) an imaging lens.
  • phase difference pixel 2 P for detecting a focal point by using the photoelectric converting film 91 formed on an outer side of the semiconductor substrate 12 also in the fourth to sixth embodiments.
  • the structure illustrated as the fourth to sixth embodiments is the surface irradiation type pixel structure, this may also be a rear surface irradiation type pixel structure as that of the first to third embodiments.
  • phase difference pixels 2 P A and 2 P B are changed to white pixels also in the fifth and sixth embodiments.
  • a lower electrode 53 d of a dummy pixel 2 D of the first to third embodiments and the element separating electrode 81 of the fourth to sixth embodiments are the electrodes extending at least to the boundary of the pixel.
  • FIGS. 18A to 25B a method of manufacturing a power supply unit to an upper electrode 53 b not illustrated in FIG. 4 is also illustrated.
  • photodiodes PD 1 and PD 2 , a conductive plug 46 , a FD unit 49 , a conductive plug 122 for supplying power to the upper electrode 53 b and the like are formed in a semiconductor region 41 of a semiconductor substrate 12 .
  • An outer periphery of the conductive plug 122 is covered with a SiO2 or SiN insulating film 123 .
  • a plurality of pixel transistors which reads charges accumulated in the photodiodes PD 1 and PD 2 and a multi-layer wiring layer 44 formed of a plurality of wiring layers and an interlayer insulating film are formed on a surface side (lower side in the drawing) of the semiconductor substrate 12 .
  • a transparent insulating film 51 A is formed to have a predetermined film thickness on an interface on a rear surface side of the semiconductor substrate 12 .
  • a metal material 201 such as tungsten (W), aluminum (Al), and copper (Cu) is formed on an entire surface of an upper side of the transparent insulating film 51 A including an opened dug portion of the transparent insulating film 51 A.
  • the metal material 201 formed on the entire surface of the transparent insulating film 51 A is patterned with only a desired region left by lithography as illustrated in FIG. 19A , and according to this, an interpixel light shielding film 55 is formed.
  • a transparent insulating film 51 B is stacked above the transparent insulating film 51 A and the interpixel light shielding film 55 as illustrated in FIG. 19B , and thereafter only a region connected to the conductive plug 46 out of the stacked transparent insulating film 51 B is opened again by lithography as illustrated in FIG. 19C .
  • a metal material 202 is formed on an entire surface on an upper side of the transparent insulating film 51 B including an opened dug portion of the transparent insulating film 51 B as illustrated in FIG. 19D , and thereafter, the metal material 202 on a surface layer is removed by chemical mechanical polishing (CMP), so that metal wiring 54 penetrating the transparent insulating films 51 A and 51 B is formed as illustrated in FIG. 20A .
  • CMP chemical mechanical polishing
  • an indium tin oxide (ITO) film 203 is deposited on the transparent insulating film 51 B as illustrated in FIG. 20B and is patterned with only a desired region left by lithography, and according to this, a lower electrode 53 a of a normal pixel 2 X, a lower electrode 53 c of a phase difference pixel 2 P A , and a lower electrode 53 d of a dummy pixel 2 D A are formed as illustrated in FIG. 20C .
  • ITO indium tin oxide
  • the transparent insulating film 51 C is formed to have a predetermined film thickness on the transparent insulating film 51 B including the lower electrodes 53 a , 53 c , and 53 d as illustrated in FIG. 20D .
  • the transparent insulating film 51 C is removed by chemical mechanical polishing (CMP), for example, until this has the same film thickness as that of the lower electrode 53 a and the like.
  • CMP chemical mechanical polishing
  • a photoelectric converting material 204 which performs photoelectric conversion on green wavelength light is formed on upper surfaces of the lower electrodes 53 a , 53 c , and 53 d and the transparent insulating film 51 as illustrated in FIG. 21B , and thereafter, an indium tin oxide (ITO) film 205 is formed thereafter, for example, as illustrated in FIG. 21C .
  • ITO indium tin oxide
  • a photoelectric converting film 52 and the upper electrode 53 b shared by the normal pixel 2 X, the phase difference pixel 2 P, and the dummy pixel 2 D are completed as illustrated in FIG. 21D by etching with only a desired region left.
  • a highly refractive material 206 A of a nitride film and the like serving as a high refractive index layer 56 is formed on upper surfaces of the upper electrode 53 b in a pixel region and the transparent insulating film 51 on an outer peripheral portion of the pixel array unit 3 .
  • a contact opening 207 is formed in a place serving as a contact portion of the upper electrode 53 b and a contact opening 208 is formed in a place serving as a contact portion with the conductive plug 122 as illustrated in FIG. 22B .
  • connection wiring 124 which connects the conductive plug 122 to the upper electrode 53 b is completed.
  • a highly refractive material 206 B of the same material as that of the highly refractive material 206 A is further formed on the highly refractive material 206 A and the connection wiring 124 .
  • the stacked highly refractive materials 206 A and 206 B serve as the high refractive index layer 56 .
  • a resin material 210 being a material of the on-chip lens 57 is further formed on an upper surface of the high refractive index layer 56 as illustrated in FIG. 24B .
  • a photo resist 211 is formed into a lens shape as illustrated in FIG. 25A .
  • the on-chip lens 57 is formed on an uppermost portion of each pixel 2 as illustrated in FIG. 25B by etching back on the basis of the lens-shaped photo resist 211 .
  • the pixel 2 of the first embodiment illustrated in FIG. 4 may be manufactured in the above-described manner. Meanwhile, the photoelectric converting unit 61 of the pixel 2 may be similarly manufactured also in the second to sixth embodiments.
  • the technology of the present disclosure is not limited to that to a solid-state image sensor. That is to say, the technology of the present disclosure is applicable to general electronic devices using the solid-state image sensor as an image capturing unit (photoelectric converting unit) such as an imaging device such as a digital still camera and a video camera, a portable terminal device having an imaging function, and a copying machine using the solid-state image sensor in an image reading unit.
  • the solid-state image sensor may be in a form of a single chip, or may be in a form of a module having the imaging function obtained by packaging an imaging unit, a signal processor, or an optical system.
  • FIG. 26 is a block diagram illustrating a configuration example of the imaging device as the electronic device according to the present disclosure.
  • An imaging device 300 in FIG. 26 is provided with an optical unit 301 formed of a lens group and the like, a solid-state image sensor (imaging device) 302 to which a configuration of the solid-state image sensor 1 in FIG. 1 is adopted, and a digital signal processor (DSP) circuit 303 which is a camera signal processing circuit.
  • the imaging device 300 is also provided with a frame memory 304 , a display unit 305 , a recording unit 306 , an operation unit 307 , and a power supply unit 308 .
  • the DSP circuit 303 , the frame memory 304 , the display unit 305 , the recording unit 306 , the operation unit 307 , and the power supply unit 308 are connected to one another through a bus line 309 .
  • the optical unit 301 captures incident light (image light) from an object and forms an image on an imaging surface of the solid-state image sensor 302 .
  • the solid-state image sensor 302 converts an amount of the incident light the image of which is formed on the imaging surface by the optical unit 301 to an electric signal in pixel unit and outputs the same as a pixel signal.
  • the solid-state image sensor 1 in FIG. 1 that is to say, the solid-state image sensor which includes a pixel structure of the above-described normal pixel 2 X, phase difference pixel 2 P and the like may be used as the solid-state image sensor 302 .
  • the display unit 305 formed of a panel display device such as a liquid crystal panel and an organic electro luminescence (EL) panel, for example, displays a moving image or a still image imaged by the solid-state image sensor 302 .
  • the recording unit 306 records the moving image or the still image imaged by the solid-state image sensor 302 in a recording medium such as a hard disk and a semiconductor memory.
  • the operation unit 307 issues an operation command regarding various functions of the imaging device 300 under operation by a user.
  • the power supply unit 308 appropriately supplies various power sources serving as operation power sources of the DSP circuit 303 , the frame memory 304 , the display unit 305 , the recording unit 306 , and the operation unit 307 to supply targets.
  • the phase difference pixel As described above, it is possible to realize the phase difference pixel while avoiding an increase in the number of steps by adopting the solid-state image sensor 1 including the pixel 2 according to the above-described embodiments as the solid-state image sensor 302 . Therefore, it is possible to improve a quality of the imaged image also in the imaging device 300 such as the video camera, the digital still camera, and further a camera module for a mobile device such as a cellular phone.
  • the imaging device 300 such as the video camera, the digital still camera, and further a camera module for a mobile device such as a cellular phone.
  • the longitudinal direction spectral solid-state image sensor including one photoelectric converting layer (photoelectric converting film 52 ) above a semiconductor substrate 12 and including two inorganic photoelectric converting layers (photodiodes PD 1 and PD 2 ) in the semiconductor substrate 12 is described.
  • the technology of the present disclosure is similarly applicable to the longitudinal direction spectral solid-state image sensor including two photoelectric converting layers above the semiconductor substrate 12 and including one inorganic photoelectric converting layer in the semiconductor substrate 12 .
  • the organic photoelectric converting material is used as the photoelectric converting film 52 of the photoelectric converting unit 61 formed above the semiconductor substrate 12 in the above-described embodiments, it is also possible to adopt an inorganic photoelectric converting material.
  • the inorganic photoelectric converting material includes crystalline silicon, amorphous silicon, and a compound semiconductor such as a Cu—In—Ga—Se compound (CIGS), a Cu—In—Se compound (CIS), a chalcopyrite structure semiconductor, and GaAs, for example.
  • the planar size of the lower electrode 53 c of the phase difference pixel 2 P is half the size of the lower electrode 53 a of the normal pixel 2 X in the above-described embodiments, there is no limitation. It is sufficient that the sensitivities of the photoelectric converting units 61 of the phase difference pixels 2 P are asymmetrical with respect to the light incident angle and the photoelectric conversion regions of the phase difference pixels 2 P A and 2 P B are symmetrical to each other.
  • the upper electrode 53 b forming the photoelectric converting unit 61 is formed on the entire surface so as to be shared by all the pixels and the lower electrode 53 a is formed for each pixel in the above-described embodiments, it is also possible to form the upper electrode 53 b for each pixel and form the lower electrode 53 a on the entire surface so as to be shared by all the pixels. It is also possible to form both the lower electrode 53 a and the upper electrode 53 b for each pixel.
  • the present disclosure is also applicable to the solid-state image sensor in which a positive hole is used as the signal charge. That is, the first conductivity type may be the N-type, the second conductivity type may be the P-type, and the conductivity types of the above-described respective semiconductor regions may be reversed.
  • the technology of the present disclosure is applicable not only to the solid-state image sensor which senses incident light amount distribution of visible light and images as an image but also to the general solid-state image sensor (physical amount distribution sensing device) such as the solid-state image sensor which images incident amount distribution of infrared rays, X-rays, or particles as an image, or a fingerprint detecting sensor which senses distribution of other physical amounts such as a pressure and capacitance and images as an image in a broad sense.
  • the general solid-state image sensor physical amount distribution sensing device
  • the solid-state image sensor which images incident amount distribution of infrared rays, X-rays, or particles as an image
  • a fingerprint detecting sensor which senses distribution of other physical amounts such as a pressure and capacitance and images as an image in a broad sense.
  • the present disclosure may also have the following configuration.
  • a solid-state image sensor including:
  • a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel;
  • a second pixel including the photoelectric converting unit in which the separated electrode is formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size.
  • the third electrode is connected to a charge holding unit which holds a charge generated by the photoelectric converting unit.
  • the third electrode is the separated electrode of an adjacent pixel.
  • the third electrode lies across three pixels including the second pixel and an adjacent pixel.
  • the third electrode is connected to wiring which supplies fixed potential.
  • the third electrode is an element separating electrode formed between separated electrodes of adjacent pixels.
  • the third electrode is an isolated pattern which is not connected to wiring.
  • the second pixel is a phase difference pixel which generates a signal for detecting a focal point.
  • the photoelectric converting film is a film which performs photoelectric conversion on light of a wavelength of a predetermined color.
  • the photoelectric converting film is a film which performs the photoelectric conversion on green wavelength light.
  • the second pixel is further provided with an inorganic photoelectric converting unit in a semiconductor substrate, and
  • the inorganic photoelectric converting unit performs the photoelectric conversion on light of a wavelength which is not subjected to the photoelectric conversion by the photoelectric converting unit.
  • the photoelectric converting film is a film capable of performing photoelectric conversion on light of wavelengths of red, green, and blue.
  • a red, green, or blue color filter is arranged above the photoelectric converting film, and
  • the photoelectric converting film performs the photoelectric conversion on light which passes through the color filter.
  • a method of manufacturing a solid-state image sensor including:
  • first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel, and
  • a second pixel including the photoelectric converting unit in which the separated electrode is formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size.
  • An electronic device including:
  • a solid-state image sensor including:
  • a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel;
  • a second pixel including the photoelectric converting unit in which the separated electrode is formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size.

Abstract

A more preferable pixel for detecting a focal point may be formed by using a photoelectric converting film. A solid-state image sensor includes a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the same from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel, and a second pixel including the photoelectric converting unit in which the separated electrode is formed to have a planar size smaller than that of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size. The present disclosure is applicable to the solid-state image sensor and the like, for example.

Description

    CROSS REFERENCE TO RELATED APPLICATIONS
  • This application is a continuation of and claims priority to U.S. patent application Ser. No. 16/516,871, filed Jul. 19, 2019, which is a continuation of and claims priority to U.S. patent application Ser. No. 15/521,718, filed Apr. 25, 2017, now U.S. Pat. No. 10,453,890, which is a national stage application under 35 U.S.C. 371 and claims the benefit of PCT Application No. PCT/JP2015/079820 having an international filing date of Oct. 22, 2015, which designated the United States, which PCT application claimed the benefit of Japanese Patent Application No. 2014-225190 filed Nov. 5, 2014, the disclosures of which are incorporated herein by reference in their entirety.
    • TECHNICAL FIELD
  • The present disclosure relates to a solid-state image sensor, a method of manufacturing the same, and an electronic device, and especially relates to the solid-state image sensor capable of forming a more preferable pixel for detecting a focal point by using a photoelectric converting film, the method of manufacturing the same, and the electronic device.
    • BACKGROUND ART
  • A solid-state image sensor in which a semiconductor is used is mounted on many devices such as a digital camera, a video camera, a monitoring camera, a copying machine, and a fax machine. Recently, a so-called CMOS image sensor manufactured by a complementary metal oxide semiconductor (CMOS) process together with a peripheral circuit is often used as the solid-state image sensor.
  • There is the CMOS image sensor in which a method of using pixels for detecting a focal point with sensitivities asymmetrical with respect to a light incident angle is adopted as an automatic focusing function of a camera. For example, in Patent Document 1, a photodiode in a pixel is divided into two and one of them with a smaller area is used for detecting a focal point as a method of realizing the pixel for detecting a focal point.
  • Also, recently, an image sensor in which an organic semiconductor and an inorganic compound semiconductor are used as a photoelectric converting film is developed. This generally has an element structure including the photoelectric converting film and electrodes interposing the same from above and below in which at least one of the upper and lower electrodes is separated for each pixel. Herein also, a method of using the pixel for detecting a focal point is suggested.
  • In Patent Document 2, an organic photoelectric converting element also having a color filter function arranged with the same optical path length as a silicon photodiode of a certain pixel is divided into two in the pixel and used as a pair, and according to this, light with different phase difference is detected and a focal point may be detected. Patent Document 3 enables focal point detection by using a pair of pixels provided with a light shielding film on a light incident side in an organic photoelectric converting element for detecting phase difference.
    • CITATION LIST Patent Document
    • Patent Document 1: Japanese Patent Application Laid-Open No. 2012-37777
    • Patent Document 2: Japanese Patent Application Laid-Open No. 2013-145292
    • Patent Document 3: Japanese Patent Application Laid-Open No. 2014-67948
    SUMMARY OF THE INVENTION Problems to be Solved by the Invention
  • However, since a photoelectric converting film for detecting a focal point also serves as color filters in Bayer arrangement in the method of realizing in Patent Document 2, it is required to separate the photoelectric converting film for each pixel. Therefore, dark current due to separation of the photoelectric converting film might be deteriorated.
  • In the realizing method in Patent Document 3 in which the light shielding film is used, when a photodiode is provided on a silicon layer below a photoelectric converting film, light received there is also shielded and an obtained signal becomes smaller.
  • The present disclosure is achieved in view of such a condition, and an object thereof is to form a more preferable pixel for detecting a focal point by using the photoelectric converting film.
    • Solutions to Problems
  • A solid-state image sensor according a first aspect of the present disclosure is provided with a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel, and a second pixel including the photoelectric converting unit in which the separated electrode is formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size.
  • A method of manufacturing a solid-state image sensor according to a second aspect of the present disclosure forms a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel, and a second pixel including the photoelectric converting unit in which the separated electrode is formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size.
  • An electronic device according to a third aspect of the present disclosure is provided with a solid-state image sensor including a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel, and a second pixel including the photoelectric converting unit in which the separated electrode is formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size.
  • In the first to third aspects of the present disclosure, a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel, and a second pixel including the photoelectric converting unit in which the separated electrode formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size are provided.
  • The solid-state image sensor and the electronic device may be independent devices or may be modules incorporated in other devices.
    • Effects of the Invention
  • According to the first to third aspects of the present disclosure, a more preferable pixel for detecting a focal point may be formed by using a photoelectric converting film.
  • Meanwhile, the effect is not especially limited to the effects described herein; this may also any effect described in the present disclosure.
    • BRIEF DESCRIPTION OF DRAWINGS
  • FIG. 1 is a view illustrating a schematic configuration of a solid-state image sensor according to the present disclosure.
  • FIG. 2 is a cross-sectional configuration diagram illustrating a cross-sectional configuration of a normal pixel.
  • FIG. 3 is a view illustrating a planar layout of a lower electrode of a first embodiment.
  • FIG. 4 is a cross-sectional configuration diagram taken along line Y1-Y1′ in FIG. 3.
  • FIG. 5 is a cross-sectional configuration diagram taken along line Y2-Y2′ in FIG. 3.
  • FIG. 6 is a view illustrating a planar layout of a lower electrode of a second embodiment.
  • FIG. 7 is a cross-sectional configuration diagram taken along line Y11-Y11′ in FIG. 6.
  • FIG. 8 is a view illustrating a planar layout of a third embodiment.
  • FIG. 9 is a cross-sectional configuration diagram taken along line X11-X11′ in FIG. 8.
  • FIG. 10 is a cross-sectional configuration diagram taken along line Y21-X21′ in FIG. 8.
  • FIG. 11 is a cross-sectional configuration diagram taken along line Y22-Y22′ in FIG. 8.
  • FIG. 12 is a view illustrating a variation of the third embodiment.
  • FIG. 13 is a view illustrating a variation of the third embodiment.
  • FIG. 14 is a cross-sectional configuration diagram of a pixel of a fourth embodiment.
  • FIG. 15 is a view illustrating a layout example of color filters.
  • FIG. 16 is a cross-sectional configuration diagram of a pixel of a fifth embodiment.
  • FIG. 17 is a cross-sectional configuration diagram of a pixel of a sixth embodiment.
  • FIGS. 18A to 18D are a view illustrating a method of manufacturing of the first embodiment.
  • FIGS. 19A to 19D are a view illustrating the method of manufacturing of the first embodiment.
  • FIGS. 20A to 20D are a view illustrating the method of manufacturing of the first embodiment.
  • FIGS. 21A to 21D are a view illustrating the method of manufacturing of the first embodiment.
  • FIGS. 22A and 22B are a view illustrating the method of manufacturing of the first embodiment.
  • FIGS. 23A and 23B are a view illustrating the method of manufacturing of the first embodiment.
  • FIGS. 24A and 24B are a view illustrating the method of manufacturing of the first embodiment.
  • FIG. 25A and 25B are a view illustrating the method of manufacturing of the first embodiment.
  • FIG. 26 is a block diagram illustrating a configuration example of an imaging device as an electronic device according to the present disclosure.
    •  MODE FOR CARRYING OUT THE INVENTION
  • A mode for carrying out the present disclosure (hereinafter, referred to as an embodiment) is hereinafter described. Meanwhile, the description is given in the following order.
  • 1. Schematic Configuration Example of Solid-State Image Sensor
  • 2. First Embodiment of Pixel (Configuration in Which Each of Pair of Phase Difference Pixels Includes Dummy Pixel)
  • 3. Second Embodiment of Pixel (Configuration in Which Pair of Phase Difference Pixels Includes Shared Dummy Pixel)
  • 4. Third Embodiment of Pixel (Configuration in Which Element Separating Electrode Is Extended to Phase Difference Pixel)
  • 5. Fourth Embodiment of Pixel (First Configuration in Which Photoelectric Converting Film Receives Light of All Wavelengths)
  • 6. Fifth Embodiment of Pixel (Second Configuration in Which Photoelectric Converting Film Receives Light of All Wavelengths)
  • 7. Sixth Embodiment of Pixel (Third Configuration in Which Photoelectric Converting Film Receives Light of All Wavelengths)
  • 8. Manufacturing Method of First Embodiment
  • 9. Application Example to Electronic Device
  • <1. Schematic Configuration Example of Solid-State Image Sensor>
  • FIG. 1 illustrates a schematic configuration of a solid-state image sensor according to the present disclosure.
  • A solid-state image sensor 1 in FIG. 1 includes a pixel array unit 3 obtained by arranging pixels 2 in a two-dimensional manner to form a matrix on a semiconductor substrate 12 formed of silicon (Si), for example, as a semiconductor, and a peripheral circuit unit around the same. The peripheral circuit unit includes a vertical driving circuit 4, a column signal processing circuit 5, a horizontal driving circuit 6, an output circuit 7, a control circuit 8 and the like.
  • The pixels 2 arranged in a two-dimensional manner to form a matrix in the pixel array unit 3 include a normal pixel 2X which generates a signal for generating an image and a phase difference pixel 2P which generates a signal for detecting a focal point as described later with reference to FIG. 3 and the like. There also is a case in which a dummy pixel 2D is arranged adjacent to the phase difference pixel 2P.
  • The vertical driving circuit 4 formed of a shift register, for example, selects pixel driving wiring 10, supplies a pulse for driving the pixel 2 to the selected pixel driving wiring 10, and drives the pixels 2 in a row unit. That is to say, the vertical driving circuit 4 sequentially selects to scan the pixels 2 in the pixel array unit 3 in a row unit in a vertical direction and supplies a pixel signal based on a signal charge generated according to a light receiving amount by a photoelectric converting unit of each pixel 2 to the column signal processing circuit 5 through a vertical signal line 9.
  • The column signal processing circuit 5 arranged for each column of the pixels 2 performs signal processing such as noise removal on the signals output from the pixels 2 of one row for each pixel column. For example, the column signal processing circuit 5 performs the signal processing such as correlated double sampling (CDS) for removing a fixed pattern noise specific to the pixel and AD conversion.
  • The horizontal driving circuit 6 formed of a shift register, for example, sequentially selects the column signal processing circuits 5 by sequentially outputting horizontal scanning pulses and outputs the pixel signal from each of the column signal processing circuits 5 to a horizontal signal line 11.
  • The output circuit 7 performs predetermined signal processing on the signals sequentially supplied from the column signal processing circuits 5 through the horizontal signal line 11 to output through an output terminal 13. There is a case in which the output circuit 7 merely buffers, for example, or a case in which this performs black level adjustment, column variation correction, and various types of digital signal processing.
  • The control circuit 8 receives an input clock and data which designates an operation mode and the like, and also outputs data such as internal information of the solid-state image sensor 1. That is, the control circuit 8 generates a clock signal and a control signal which serve as a reference for operation of the vertical driving circuit 4, the column signal processing circuit 5, the horizontal driving circuit 6 and the like on the basis of a vertical synchronization signal, a horizontal synchronization signal, and a master clock. The control circuit 8 then outputs the generated clock signal and control signal to the vertical driving circuit 4, the column signal processing circuit 5, the horizontal driving circuit 6, and the like.
  • The solid-state image sensor 1 configured in the above-described manner is a so-called column AD type CMOS image sensor in which the column signal processing circuit 5 which performs the CDS processing and AD conversion processing is arranged for each pixel column.
  • <2. First Embodiment of Pixel>
  • <Cross-Sectional Configuration of Normal Pixel>
  • A cross-sectional configuration of a normal pixel of a solid-state image sensor 1 is described with reference to FIG. 2.
  • FIG. 2 is a view illustrating the cross-sectional configuration of a normal pixel 2X of the solid-state image sensor 1 in FIG. 1.
  • Photodiodes PD1 and PD2 by PN junction are formed in a depth direction by forming second conductivity type (for example, N-type) semiconductor regions 42 and 43 so as to be stacked in the depth direction in a first conductivity type (for example, P-type) semiconductor region 41 of a semiconductor substrate 12. The photodiode PD1 including the semiconductor region 42 as a charge accumulation region is an inorganic photoelectric converting unit which receives blue light to perform photoelectric conversion, and the photodiode PD2 including the semiconductor region 43 as a charge accumulation region is an inorganic photoelectric converting unit which receives red light to perform the photoelectric conversion.
  • A plurality of pixel transistors which reads the charges accumulated in the photodiodes PD1 and PD2 and a multi-layer wiring layer 44 formed of a plurality of wiring layers and an interlayer insulating film are formed on a surface side (lower side in the drawing) of the semiconductor substrate 12. Meanwhile, the multi-layer wiring layer 44 is not illustrated in detail in FIG. 2. A plurality of pixel transistors is formed of four MOS transistors which are a transfer transistor, a selection transistor, a reset transistor, and an amplification transistor, for example.
  • A conductive plug 46 for extracting the charge obtained by the photoelectric conversion by a photoelectric converting film 52 to be described later to a side of the multi-layer wiring layer 44 is formed on the semiconductor substrate 12 so as to penetrate (the semiconductor region 41 of) the semiconductor substrate 12. An SiO2 or SiN insulating film 47 is formed on an outer periphery of the conductive plug 46 so as to inhibit short-circuit with the semiconductor region 41.
  • The conductive plug 46 is connected to a floating diffusion unit (FD unit) 49 formed of a second conductivity type (for example, N-type) semiconductor region in the semiconductor substrate 12 by means of metal wiring 48 formed in the multi-layer wiring layer 44. The FD unit 49 is a region in which the charge obtained by the photoelectric conversion by the photoelectric converting film 52 is temporarily held before being read. The charge held in the FD unit 49 is output to the column signal processing circuit 5 on a subsequent stage through the amplification transistor and the like as is the case with the charges generated by the photodiodes PD1 and PD2. However, the transfer transistor required in the photodiodes PD1 and PD2 is not required when the charge generated by the photoelectric converting film 52 is output as a signal. Therefore, the photoelectric conversion using the photoelectric converting film 52 has an advantage that light receiving areas of the photodiodes PD1 and PD2 are not narrowed.
  • A transparent insulating film 51 formed of two or three layers of a hafnium oxide (HfO2) film and a silicon oxide film is formed, for example, on an interface on a rear surface side (upper side in the drawing) of the semiconductor substrate 12.
  • The photoelectric converting film 52 is arranged above the transparent insulating film 51 so as to be interposed between a lower electrode 53 a below the same and an upper electrode 53 b above the same. Out of a region in which the photoelectric converting film 52 is formed, a region interposed between the lower electrode 53 a and the upper electrode 53 b is the region in which incident light is subjected to the photoelectric conversion; the photoelectric converting film 52, the lower electrode 53 a, and the upper electrode 53 b form a photoelectric converting unit 61. As a film which performs the photoelectric conversion on green wavelength light, the photoelectric converting film 52 is formed of an organic photoelectric converting material containing a rhodamine dye, a merocyanine dye, or quinacridone, for example. The lower electrode 53 a and the upper electrode 53 b are formed of an indium tin oxide (ITO) film, an indium zinc oxide film and the like, for example.
  • Meanwhile, in a case in which the photoelectric converting film 52 is a film which performs the photoelectric conversion on red wavelength light, an organic photoelectric converting material containing a phthalocyanine dye may be used, for example. Also, in a case of the film which performs the photoelectric conversion on blue wavelength light, an organic photoelectric converting material containing a coumarin dye, tris(8-hydroxyquinoline) aluminum (Alq3), the merocyanine dye and the like may be used.
  • Although the upper electrode 53 b is formed on an entire surface so as to be shared by all the pixels, the lower electrode 53 a is formed for each pixel and is connected to the conductive plug 46 of the semiconductor substrate 12 by means of metal wiring 54 penetrating the transparent insulating film 51. The metal wiring 54 formed of materials such as tungsten (W), aluminum (Al), and copper (Cu) is also formed in a planar direction at predetermined depth of the transparent insulating film 51 and also serves as an interpixel light shielding film 55 which inhibits the light from entering an adjacent pixel.
  • A high refractive index layer 56 is formed of an inorganic film such as a silicon nitride film (SiN), silicon oxynitride film (SiON), and silicon carbide (SiC) on an upper surface of the upper electrode 53 b. Also, an on-chip lens 57 is formed above the high refractive index layer 56. The silicon nitride film (SiN) or a resin material such as a styrene resin, an acrylic resin, a styrene acrylic copolymer resin, or a siloxane resin, for example, is used as a material of the on-chip lens 57. In this pixel structure, since a distance between the photoelectric converting film 52 and the on-chip lens 57 is short, light incident angle dependency is smaller in a phase difference pixel 2P, so that the high refractive index layer 56 has an effect of enlarging a refraction angle and improving light condensing efficiency.
  • In FIG. 2, three normal pixels 2X configured in the above-described manner are arranged side by side.
  • The solid-state image sensor 1 in which the normal pixels 2X formed in this manner are arranged in a two-dimensional manner is a rear surface irradiation type CMOS solid-state image sensor in which the light enters from a rear surface side on an opposite side of the surface side of the semiconductor substrate 12 on which the multi-layer wiring layer 44 is formed.
  • Also, the solid-state image sensor 1 is a longitudinal direction spectral solid-state image sensor which performs the photoelectric conversion by the photoelectric converting film 52 formed above the semiconductor substrate (silicon layer) 12 on the green light and performs the photoelectric conversion by the photodiodes PD1 and PD2 in the semiconductor substrate 12 on the blue light and red light.
  • <Planar Layout of Lower Electrode>
  • FIG. 3 is a view illustrating a planar layout of the lower electrode in the pixel array unit 3.
  • As illustrated in FIG. 3, out of the pixels 2 arranged in a two-dimensional manner in the pixel array unit 3, in the normal pixel 2X, the lower electrode 53 a is formed for each pixel. The cross-sectional view illustrated in FIG. 2 corresponds a cross-sectional view of a portion in which the three normal pixels 2X are arranged in a horizontal direction indicated by line X1-X1′ in FIG. 3, for example.
  • On the other hand, the pixels 2 arranged in a two-dimensional manner in the pixel array unit 3 include the pixel 2 including a lower electrode 53 c a planar size of which is made smaller than that of the lower electrode 53 a of the normal pixel 2X and the pixel 2 including a lower electrode 53 d enlarged to a region which is vacant due to a decrease in size of the lower electrode 53 c.
  • The pixel 2 including the downsized lower electrode 53 c is the phase difference pixel 2P which generates a signal for detecting a focal point and the pixel 2 including the enlarged lower electrode 53 d is a dummy pixel 2D arranged adjacent to the phase difference pixel 2P.
  • A pair (two) of the phase difference pixels 2P configured such that sensitivities are asymmetrical with respect to a light incident angle is arranged in the pixel array unit 3. The two phase difference pixels 2P which form a pair are represented as a type A phase difference pixel 2PA and a type B phase difference pixel 2PB. Also, the dummy pixel 2D arranged adjacent to the phase difference pixel 2PA is represented as a dummy pixel 2DA and the dummy pixel 2D arranged adjacent to the phase difference pixel 2PB is represented as a dummy pixel 2DB.
  • In an example in FIG. 3, the phase difference pixel 2PA is the pixel in which the lower electrode 53 c is formed so as to receive light only by a left side in the pixel as compared to the normal pixel 2X, and the phase difference pixel 2PB is the pixel in which the lower electrode 53 c is formed only on a right side in the pixel such that a photoelectric conversion region is symmetrical to that in the phase difference pixel 2PA.
  • Meanwhile, although a pair of the phase difference pixel 2PA and the dummy pixel 2DA and a pair of the phase difference pixel 2PB and the dummy pixel 2DB are arranged so as to be adjacent in a longitudinal direction (vertical direction) in the example in FIG. 3, they are not necessarily arranged so as to be adjacent in the longitudinal direction. For example, the pair of the phase difference pixel 2PA and the dummy pixel 2DA and the pair of the phase difference pixel 2PB and the dummy pixel 2DB may be arranged with one or more pixels interposed therebetween or arranged so as to be adjacent in a lateral direction (horizontal direction).
  • Also, although the lower electrodes 53 c of the phase difference pixels 2PA and 2PB are downsized in the lateral direction (horizontal direction) as compared to the lower electrode 53 a in the normal pixel 2X in the example in FIG. 3, they may also be downsized in the longitudinal direction (vertical direction). When the lower electrodes 53 c of the phase difference pixels 2PA and 2PB are downsized in the longitudinal direction, the phase difference pixel 2PA and the dummy pixel 2DA are arranged so as to be adjacent in the longitudinal direction and the phase difference pixel 2PB and the dummy pixel 2DB are also arranged so as to be adjacent in the longitudinal direction.
  • Furthermore, the pair of the phase difference pixels 2PA and 2PB including the lower electrodes 53 c downsized in the lateral direction and the pair of the phase difference pixels 2PA and 2PB including the lower electrodes 53 c downsized in the longitudinal direction may be mixed in the pixel array unit 3.
  • Displacement in image occurs between the pixel signal from the phase difference pixel 2PA and the pixel signal from the phase difference pixel 2PB because the lower electrodes 53 c are formed in different positions. It is possible to realize automatic focusing by calculating a defocusing amount by calculating a phase displacement amount from the displacement in image to adjust (move) an imaging lens.
  • <Cross-Sectional Configuration of Phase Difference Pixel>
  • FIG. 4 illustrates a cross-sectional configuration taken along line Y1-Y1′ in FIG. 3 in which one normal pixel 2X and the pair of the phase difference pixel 2PA and the dummy pixel 2DA are included.
  • FIG. 5 illustrates a cross-sectional configuration taken along line Y2-Y2′ in FIG. 3 in which one normal pixel 2X and the pair of the phase difference pixel 2PB and the dummy pixel 2DB are included.
  • As illustrated in FIGS. 4 and 5, the lower electrode 53 c of the phase difference pixel 2P (2PA or 2PB) is downsized in the lateral direction (horizontal direction) as compared to the lower electrode 53 a of the normal pixel 2X and the lower electrode 53 d of the dummy pixel 2D (2DA or 2DB) is extended to a region which is vacant due to downsizing to be formed. Although an interval in the planar direction between the lower electrode 53 c of the phase difference pixel 2P and the lower electrode 53 d of the dummy pixel 2D is set to be the same as the interval between the lower electrodes 53 a of two adjacent normal pixels 2X, they are not necessarily the same.
  • In the phase difference pixel 2P and the dummy pixel 2D, the configuration other than the lower electrodes 53 c and 53 d is similar to that of the normal pixel 2X. Therefore, B signals and R signals generated by the photodiodes PD1 and PD2 of the phase difference pixel 2P and the dummy pixel 2D may be utilized as the signals for generating an image.
  • A G signal generated by the photoelectric converting unit 61, that is to say, the photoelectric converting film 52, the upper electrode 53 b, and the lower electrode 53 c of the phase difference pixel 2P is output to the FD unit 49 through the metal wiring 54 and the conductive plug 46 to be utilized as the signal for detecting a focal point. The G signal for generating an image of the phase difference pixel 2P is calculated by interpolation from the G signals of a plurality of normal pixels 2X around the phase difference pixel 2P, for example.
  • On the other hand, the G signal generated by the photoelectric converting unit 61, that is to say, the photoelectric converting film 52, the upper electrode 53 b, and the lower electrode 53 d of the dummy pixel 2D is output to the FD unit 49 through the metal wiring 54 and the conductive plug 46, but this is discharged without being utilized. The G signal for generating an image of the dummy pixel 2D is also calculated by the interpolation from the G signals of a plurality of normal pixels 2X around the dummy pixel 2D, for example.
  • According to the first embodiment of the phase difference pixel 2P configured in the above-described manner, it is not required to form a light shielding film on an upper surface of the photoelectric converting film 52 for each color, so that it is possible to realize the phase difference pixel while avoiding an increase in the number of steps for forming the light shielding film. Also, it is not required to separate the photoelectric converting film 52 between the pixels, so that it is possible to inhibit dark current generated when the photoelectric converting film 52 is separated between the pixels.
  • Therefore, it is possible to form a more preferable phase difference pixel 2P for detecting a focal point by using the photoelectric converting film 52 formed on an outer side of the semiconductor substrate 12.
  • Meanwhile, in the pixel structure illustrated as the first embodiment, since the photoelectric converting film 52 performs the photoelectric conversion on the green light, the G signal output from the phase difference pixel 2P is used as the signal for detecting a focal point; however, it is possible to arbitrarily select the color of the light on which the photoelectric conversion is performed by the photoelectric converting film 52. That is to say, in the longitudinal direction spectral solid-state image sensor, it is possible to appropriately determine the color of the light on which the photoelectric conversion is performed by the photoelectric converting film 52 formed above the semiconductor substrate 12 and the colors of the light on which the photoelectric conversion is performed by the photodiodes PD1 and PD2 in the semiconductor substrate 12.
  • <3. Second Embodiment of Pixel>
  • <Planar Layout of Lower Electrode>
  • Next, a second embodiment is described. Meanwhile, in the description of the second embodiment and thereafter, the description of a portion corresponding to that in other embodiments indicated with the same reference sign as that of the above-described other embodiments is appropriately omitted and only a different portion is described. A normal pixel of the second embodiment is similar to that of the above-described first embodiment, so that only a phase difference pixel is described.
  • FIG. 6 is a view illustrating a planar layout of a lower electrode in a pixel array unit 3.
  • In the second embodiment, phase difference pixels 2PA and 2PB are arranged in a linear manner with a dummy pixel 2D interposed therebetween. That is to say, the phase difference pixel 2PA, the dummy pixel 2D, and the phase difference pixel 2PB are arranged in the pixel array unit 3 in this order. Therefore, the dummy pixel 2D is arranged adjacent to the phase difference pixels 2PA and 2PB; this serves as a dummy pixel 2DA arranged adjacent to the phase difference pixel 2PA and a dummy pixel 2DB arranged adjacent to the phase difference pixel 2PB. Such dummy pixel 2D is represented as a dummy pixel 2DAB.
  • In the second embodiment, the phase difference pixel 2PA includes a lower electrode 53 c formed so as to receive light only on a left side in the pixel as in the first embodiment. The phase difference pixel 2PB includes the lower electrode 53 c only on a right side in the pixel such that a photoelectric conversion region is symmetrical to that of the phase difference pixel 2PA.
  • Then, a lower electrode 53 d of the dummy pixel 2DAB arranged in the center is extended to regions of the phase difference pixels 2PA and 2PB which are vacant due to downsizing of the lower electrodes 53 c to be formed. In other words, the lower electrode 53 d of the dummy pixel 2DAB is formed so as to extend to sides of the phase difference pixels 2PA and 2PB to lie across three pixels.
  • Meanwhile, although the phase difference pixel 2PA, the dummy pixel 2D, and the phase difference pixel 2PB are arranged in a linear manner in a horizontal direction in this order in the example in FIG. 6, it is also possible to configure such that they are arranged in a linear manner in a vertical direction.
  • <Cross-Sectional Configuration of Phase Difference Pixel>
  • FIG. 7 illustrates a cross-sectional configuration taken along line Y11-Y11′ in FIG. 6 including the phase difference pixel 2PA, the dummy pixel 2DAB, and the phase difference pixel 2PB.
  • As illustrated in FIG. 7, the lower electrodes 53 c of the phase difference pixels 2PA and 2PB are downsized in a lateral direction (horizontal direction) as compared to a lower electrode 53 a of a normal pixel 2X and the lower electrode 53 d of the dummy pixel 2DAB is extended to the regions which are vacant due to the downsizing to be formed.
  • In the phase difference pixels 2PA and 2PB, a charge generated in a region interposed between an upper electrode 53 b and the lower electrode 53 c out of a region of a photoelectric converting film 52 is accumulated in a FD unit 49. Positions in which the lower electrodes 53 c are formed in the phase difference pixels 2PA and 2PB are symmetrical to each other. Displacement in image occurs between pixel signals from the phase difference pixels 2PA and 2PB because the lower electrodes 53 c are formed in different positions. It is possible to realize automatic focusing by calculating a defocusing amount by calculating a phase displacement amount from the displacement in image to adjust (move) an imaging lens.
  • According to the second embodiment of the phase difference pixel 2P configured in the above-described manner, it is not required to form a light shielding film on an upper surface of the photoelectric converting film 52 for each color, so that it is possible to realize the phase difference pixel while avoiding an increase in the number of steps for forming the light shielding film. Also, it is not required to separate the photoelectric converting film 52 between the pixels, so that it is possible to inhibit dark current generated when the photoelectric converting film 52 is separated between the pixels.
  • Therefore, it is possible to form a more preferable phase difference pixel 2P for detecting a focal point by using the photoelectric converting film 52 formed on an outer side of the semiconductor substrate 12.
  • <4. Third Embodiment of Pixel>
  • <Planar Layout of Lower Electrode>
  • Next, a third embodiment is described.
  • FIG. 8 is a view illustrating a planar layout of a lower electrode in a pixel array unit 3.
  • Meanwhile, in FIG. 8, a broken line indicating a boundary of each pixel 2 illustrated in FIGS. 3 and 6 is omitted in order to make the drawing more visible.
  • In the third embodiment, an element separating electrode 81 which separates pixels (elements) is formed between lower electrodes 53 a and 53 c adjacent to each other. A material similar to that of the lower electrodes 53 a and 53 c such as an indium tin oxide (ITO) film and an indium zinc oxide film, for example, may be used as a material of the element separating electrode 81. The element separating electrode 81 is formed between the lower electrodes 53 a and 53 c adjacent to each other in a vertical direction and in a horizontal direction, so that this is formed into a lattice shape as illustrated in FIG. 8.
  • Predetermined fixed potential is applied to the element separating electrode 81. According to this, it is possible to prevent capacity coupling between the adjacent pixels and inhibit an after image by collecting a charge generated between the pixels.
  • A phase difference pixel 2PA includes the lower electrode 53 c formed so as to receive light only on a left side in the pixel as in the first embodiment. The phase difference pixel 2PB includes the lower electrode 53 c only on a right side in the pixel such that a photoelectric conversion region is symmetrical to that of the phase difference pixel 2PA.
  • Then, the element separating electrode 81 is formed in a region which is vacant due to downsizing of the lower electrode 53 c of the phase difference pixel 2PA so as to be extended from a pixel boundary line. The element separating electrode 81 is formed also in a region which is vacant due to the downsizing of the lower electrode 53 c of the phase difference pixel 2PB so as to be extended from the pixel boundary line. That is to say, each of the phase difference pixels 2PA and 2PB has a configuration in which the element separating electrode 81 adjacent thereto is extended to the region which is vacant due to the downsized lower electrode 53 c to be formed.
  • Positions in which the lower electrodes 53 c are formed in the phase difference pixels 2PA and 2PB configured in the above-described manner are symmetrical to each other. Displacement in image occurs between pixel signals from the phase difference pixels 2PA and 2PB because the lower electrodes 53 c are formed in different positions. It is possible to realize automatic focusing by calculating a defocusing amount by calculating a phase displacement amount from the displacement in image to adjust (move) an imaging lens.
  • Meanwhile, although the lower electrodes 53 c of the phase difference pixels 2PA and 2PB are downsized in a lateral direction (horizontal direction) as compared to the lower electrode 53 a of a normal pixel 2X in the example in FIG. 8, they may also be downsized in a longitudinal direction (vertical direction). In this case, the element separating electrode 81 which separates the upper and lower lower electrodes 53 a and 53 c is formed so as to be extended in the longitudinal direction in each of the phase difference pixels 2PA and 2PB.
  • <Cross-Sectional Configuration of Pixel>
  • FIG. 9 is a cross-sectional configuration diagram taken along line X11-X11′ in FIG. 8 including two normal pixels 2X.
  • FIG. 10 is a cross-sectional configuration diagram taken along line Y21-Y21′ in FIG. 8 including one normal pixel 2X and one phase difference pixel 2PA.
  • FIG. 11 is a cross-sectional configuration diagram taken along line Y22-Y22′ in FIG. 8 including one normal pixel 2X and one phase difference pixel 2PB.
  • As illustrated in FIG. 9, in a portion in which the normal pixels 2X are adjacent to each other, the element separating electrode 81 is formed in a position on the pixel boundary in a planar direction and in the same position as that of the lower electrode 53 a in a depth direction. The element separating electrode 81 is connected to metal wiring 82 formed below the same and predetermined fixed potential is applied to the element separating electrode 81 through the metal wiring 82.
  • As illustrated in FIG. 10, in a portion in which the phase difference pixel 2PA and the normal pixel 2X are adjacent to each other, the element separating electrode 81 is formed in the region which is vacant due to the downsizing of the lower electrode 53 c of the phase difference pixel 2PA so as to be extended from the pixel boundary line.
  • Also, as illustrated in FIG. 11, in a portion in which the phase difference pixel 2PB and the normal pixel 2X are adjacent to each other, the element separating electrode 81 is formed in the region which is vacant due to the downsizing of the lower electrode 53 c of the phase difference pixel 2PB so as to be extended from the pixel boundary line.
  • The extended element separating electrode 81 is connected to the metal wiring 82 formed below the same and predetermined fixed potential is applied to the element separating electrode 81 also in FIGS. 10 and 11 as in FIG. 9. The charge generated by a photoelectric converting film 52 interposed between the extended element separating electrode 81 and an upper electrode 53 b is not connected to the FD unit 49 and is not extracted as a signal.
  • According to the third embodiment of the phase difference pixel 2P configured in the above-described manner, it is not required to form a light shielding film on an upper surface of the photoelectric converting film 52 for each color, so that it is possible to realize the phase difference pixel while avoiding an increase in the number of steps for forming the light shielding film. Also, it is not required to separate the photoelectric converting film 52 between the pixels, so that it is possible to inhibit dark current generated when the photoelectric converting film 52 is separated between the pixels.
  • Therefore, it is possible to form a more preferable phase difference pixel 2P for detecting a focal point by using the photoelectric converting film 52 formed on an outer side of the semiconductor substrate 12.
  • <Variation of Third Embodiment>
  • Although a layout is such that a normal pixel 2X is arranged adjacent to a phase difference pixel 2PA or 2PB in a vertical direction and in a horizontal direction in an example illustrated in FIG. 8, the layout may also be such that the phase difference pixels 2PA and 2PB are arranged adjacent to each other in the vertical direction or in the horizontal direction as illustrated in FIG. 12.
  • Also, although it is described that an element separating electrode 81 is extended on the assumption that the element separating electrode 81 is formed into a lattice shape on a pixel boundary in the vertical direction and in the horizontal direction in the description above, the element separating electrode 81 in the lattice shape may be omitted as illustrated in FIG. 13. Also, it is of course possible to configure such that the element separating electrode 81 in the lattice shape is omitted from the layout illustrated in FIG. 8 and only an element separating electrode 83 having an island shape is provided. In this case, predetermined fixed potential is applied only to the element separating electrode 83 having the island shape. Furthermore, a shape may be such that not an entire element separating electrode 81 in the lattice shape is omitted but only a part of the element separating electrode 81 in the lattice shape is omitted to form a H shape, for example.
  • Meanwhile, difference between the element separating electrode 83 in the island shape illustrated in FIG. 13 and a lower electrode 53 c in an island shape of a dummy pixel 2DAB of the second embodiment illustrated in FIG. 6 is that the former is connected to metal wiring 82 which supplies predetermined fixed potential and the latter is connected to a FD unit 49 which accumulates a charge. The element separating electrode 83 in the island shape illustrated in FIG. 13 may also have an isolated pattern without being connected to the metal wiring 82 formed below the same. Alternatively, it is also possible to configure such that the element separating electrode 83 in the island shape in FIG. 13 is not connected to the metal wiring 82 formed below the same but connected to the FD unit 49 to accumulate the charge to discharge.
  • <5. Fourth Embodiment of Pixel>
  • <Cross-Sectional Configuration of Pixel>
  • Next, a fourth embodiment is described.
  • In the above-described first to third embodiments, each pixel 2 receives light of all wavelengths of red (R), green (G), and blue (B) by a photoelectric converting unit 61 and photodiodes PD1 and PD2; however, fourth to sixth embodiments to be described hereinafter are different in that each pixel 2 receives only light of any of the wavelengths of red (R), green (G), and blue (B).
  • FIG. 14 being a cross-sectional configuration diagram of the pixel 2 of the fourth embodiment illustrates a cross-sectional configuration of a portion corresponding to line Y1-Y1′ in FIG. 3 in which one normal pixel 2X and a pair of a phase difference pixel 2PA and a dummy pixel 2DA are included.
  • Comparing the cross-sectional configuration of the first embodiment illustrated in FIG. 4 with the cross-sectional configuration of the fourth embodiment in FIG. 14 being the cross-sectional configuration diagrams taken along line Y1-Y1′ in FIG. 3, in FIG. 14, a photoelectric converting film 52 which performs photoelectric conversion on green wavelength light in FIG. 4 is replaced with a photoelectric converting film 91 which performs the photoelectric conversion on the light of all the wavelengths of red (R), green (G), and blue (B). Also, the photodiode PD1 which receives the blue light and the photodiode PD2 which receives the red light are not provided in a semiconductor substrate 12.
  • Furthermore, in FIG. 14, a color filter 92 which transmits the light of the wavelength of red (R), green (G), or blue (B) is newly provided between a high refractive index layer 56 and an on-chip lens 57.
  • Therefore, only the light of any of the wavelengths of red (R), green (G), and blue (B) which passes the color filter 92 achieves the photoelectric converting film 91, so that each pixel 2 receives only the light of any of the wavelengths of red (R), green (G), and blue (B).
  • Also, a rear surface irradiation type configuration in which the photoelectric converting unit 61 and the on-chip lens 57 are formed on a rear surface side opposite to a surface side on which a multi-layer wiring layer 44 is formed is adopted in the first embodiment illustrated in FIG. 4. On the other hand, in the fourth embodiment in FIG. 14, a surface irradiation type configuration in which the photoelectric converting unit 61 and the on-chip lens 57 are formed on the surface side of the semiconductor substrate 12, the side on which the multi-layer wiring layer 44 is formed is adopted.
  • More specifically, the multi-layer wiring layer 44 is formed on the surface side of the semiconductor substrate 12 and a transparent insulating film 51, a lower electrode 53 a, the photoelectric converting film 91, an upper electrode 53 b, the high refractive index layer 56 and the like are formed on an upper surface of the multi-layer wiring layer 44.
  • Since the multi-layer wiring layer 44 is formed on the surface side of the semiconductor substrate 12, the FD unit 49 which holds the charge generated by a photoelectric converting film 52 is also formed on the surface side of the semiconductor substrate 12. Therefore, in the fourth embodiment, a conductive plug 46 and an insulating film 47 for extracting the charge generated by the photoelectric converting film 91 to the rear surface side of the semiconductor substrate 12 are not provided.
  • FIG. 15 is a view illustrating a layout example of the color filters 92 illustrated so as to correspond to the planar layout in FIG. 3.
  • The color filters 92 are arranged in Bayer arrangement, for example, as illustrated in FIG. 15.
  • Meanwhile, although the phase difference pixel 2PA and a phase difference pixel 2PB are the pixels which receive a green (Gr, Gb) wavelength, the dummy pixel 2DA is the pixel which receives a red (R) wavelength, and a dummy pixel 2DB is the pixel which receives a blue (B) wavelength in the example in FIG. 15, the wavelengths (colors) of the light received by the phase difference pixel 2P and the dummy pixel 2D are not limited to this example. However, it is desirable that the wavelength of the light received by the phase difference pixel 2PA and the wavelength of the light received by the phase difference pixel 2PB are the same. Also, it is possible to make the phase difference pixels 2PA and 2PB white pixels which receive the light of all the wavelengths by using a material which transmits all the wavelengths in place of the color filter 92. When the phase difference pixels 2PA and 2PB are made the white pixels, the material used in place of the color filter 92 may be the same material as that of the high refractive index layer 56 and the on-chip lens 57, for example.
  • <6. Fifth Embodiment of Pixel>
  • <Cross-Sectional Configuration of Pixel>
  • Next, a fifth embodiment is described.
  • FIG. 16 being a cross-sectional configuration diagram of a pixel 2 of the fifth embodiment illustrates a cross-sectional configuration of a portion corresponding to line Y11-Y11′ in FIG. 6 in which phase difference pixels 2PA and 2PB and a dummy pixel 2DAB interposed therebetween are included.
  • In the fifth embodiment, a wavelength of light received by each pixel 2 is configured so as to be similar to that of the fourth embodiment described with reference to FIG. 14 and an arrangement configuration of lower electrodes 53 c and 53 d is similar to that of the second embodiment described with reference to FIG. 7.
  • That is to say, in FIG. 16, color filters 92 in Bayer arrangement is formed between a high refractive index layer 56 and an on-chip lens 57 and a photoelectric converting film 91 which performs photoelectric conversion on light of all the wavelengths of red (R), green (G), and blue (B) is formed between the lower electrode 53 c or 53 d and an upper electrode 53 b. According to this, a photoelectric converting unit 61 of each pixel 2 receives only the light of any of the wavelengths of red (R), green (G), and blue (B).
  • Also, the phase difference pixels 2PA and 2PB are arranged in a linear manner with the dummy pixel 2DAB interposed therebetween. Then, the lower electrode 53 d of the dummy pixel 2DAB arranged in the center is extended to regions which are vacant due to downsizing of the lower electrodes 53 c of the phase difference pixels 2PA and 2PB to be formed.
  • Also, a pixel structure of the fifth embodiment is a surface irradiation type structure in which the photoelectric converting unit 61 and the on-chip lens 57 are formed on a surface side of a semiconductor substrate 12, the side on which a multi-layer wiring layer 44 is formed.
  • <7. Sixth Embodiment of Pixel>
  • <Cross-Sectional Configuration of Pixel>
  • Next, a sixth embodiment is described.
  • FIG. 17 being a cross-sectional configuration diagram of a pixel 2 of the sixth embodiment illustrates a cross-sectional configuration of a portion corresponding to line Y21-Y21′ in FIG. 8 in which one normal pixel 2X and one phase difference pixel 2PA are included.
  • In the sixth embodiment, a wavelength of light received by each pixel 2 is configured so as to be similar to that of the fourth embodiment described with reference to FIG. 14 and an arrangement configuration of a lower electrode 53 c and an element separating electrode 81 is similar to that of the third embodiment described with reference to FIG. 10.
  • That is to say, in FIG. 17, color filters 92 in Bayer arrangement are formed between a high refractive index layer 56 and an on-chip lens 57 and a photoelectric converting film 91 which performs photoelectric conversion on light of all the wavelengths of red (R), green (G), and blue (B) is formed between a lower electrode 53 a or 53 c and an upper electrode 53 b. According to this, a photoelectric converting unit 61 of each pixel 2 receives only the light of any of the wavelengths of red (R), green (G), and blue (B).
  • Also, the element separating electrode 81 is formed between the phase difference pixel 2PA and the normal pixel 2X, and the element separating electrode 81 is formed in a region which is vacant due to downsizing of the lower electrode 53 c of the phase difference pixel 2PA so as to be extended from a pixel boundary line as illustrated in FIG. 17.
  • Although not illustrated, in a portion in which the normal pixels 2X of the sixth embodiment are adjacent to each other, as in FIG. 9, the element separating electrode 81 is formed in a position on the pixel boundary. Also, in a portion in which a phase difference pixel 2PB and the normal pixel 2X are adjacent to each other, as in FIG. 11, the element separating electrode 81 is formed in a region which is vacant due to the downsizing of the lower electrode 53 c of the phase difference pixel 2PB so as to be extended from the pixel boundary line.
  • Also, a pixel structure of the sixth embodiment is a surface irradiation type structure in which the photoelectric converting unit 61 and the on-chip lens 57 are formed on a surface side of a semiconductor substrate 12, the side on which a multi-layer wiring layer 44 is formed.
  • In the above-described fourth to sixth embodiments also, positions in which the lower electrodes 53 c are formed in the phase difference pixels 2PA and 2PB are symmetrical with each other. Displacement in image occurs between pixel signals from the phase difference pixels 2PA and 2PB because the lower electrodes 53 c are formed in different positions. It is possible to realize automatic focusing by calculating a defocusing amount by calculating a phase displacement amount from the displacement in image to adjust (move) an imaging lens.
  • It is not required to form a light shielding film on an upper surface of the photoelectric converting film 91 also in the fourth to sixth embodiments, so that it is possible to realize the phase difference pixel while avoiding an increase in the number of steps. Also, it is not required to separate the photoelectric converting film 91 between the pixels, so that it is possible to inhibit dark current generated when the photoelectric converting film 91 is separated between the pixels.
  • Therefore, it is possible to form a more preferable phase difference pixel 2P for detecting a focal point by using the photoelectric converting film 91 formed on an outer side of the semiconductor substrate 12 also in the fourth to sixth embodiments.
  • Meanwhile, although the structure illustrated as the fourth to sixth embodiments is the surface irradiation type pixel structure, this may also be a rear surface irradiation type pixel structure as that of the first to third embodiments.
  • It is possible to change the phase difference pixels 2PA and 2PB to white pixels also in the fifth and sixth embodiments.
  • Also, a lower electrode 53 d of a dummy pixel 2D of the first to third embodiments and the element separating electrode 81 of the fourth to sixth embodiments are the electrodes extending at least to the boundary of the pixel.
  • <8. Manufacturing Method of First Embodiment>
  • Next, a method of manufacturing a pixel 2 according to the first embodiment illustrated in FIG. 4 is described with reference to FIGS. 18A to 25B.
  • Meanwhile, in FIGS. 18A to 25B, a method of manufacturing a power supply unit to an upper electrode 53 b not illustrated in FIG. 4 is also illustrated.
  • First, as illustrated in FIG. 18A, photodiodes PD1 and PD2, a conductive plug 46, a FD unit 49, a conductive plug 122 for supplying power to the upper electrode 53 b and the like are formed in a semiconductor region 41 of a semiconductor substrate 12. An outer periphery of the conductive plug 122 is covered with a SiO2 or SiN insulating film 123.
  • Also, a plurality of pixel transistors which reads charges accumulated in the photodiodes PD1 and PD2 and a multi-layer wiring layer 44 formed of a plurality of wiring layers and an interlayer insulating film are formed on a surface side (lower side in the drawing) of the semiconductor substrate 12.
  • Then, as illustrated in FIG. 18B, a transparent insulating film 51A is formed to have a predetermined film thickness on an interface on a rear surface side of the semiconductor substrate 12.
  • Next, as illustrated in FIG. 18C, only a region connected to the conductive plug 46 out of the transparent insulating film 51A formed on the interface on the rear surface side of the semiconductor substrate 12 is opened by lithography.
  • Then, as illustrated in FIG. 18D, a metal material 201 such as tungsten (W), aluminum (Al), and copper (Cu) is formed on an entire surface of an upper side of the transparent insulating film 51A including an opened dug portion of the transparent insulating film 51A.
  • The metal material 201 formed on the entire surface of the transparent insulating film 51A is patterned with only a desired region left by lithography as illustrated in FIG. 19A, and according to this, an interpixel light shielding film 55 is formed.
  • Furthermore, a transparent insulating film 51B is stacked above the transparent insulating film 51A and the interpixel light shielding film 55 as illustrated in FIG. 19B, and thereafter only a region connected to the conductive plug 46 out of the stacked transparent insulating film 51B is opened again by lithography as illustrated in FIG. 19C.
  • Then, a metal material 202 is formed on an entire surface on an upper side of the transparent insulating film 51B including an opened dug portion of the transparent insulating film 51B as illustrated in FIG. 19D, and thereafter, the metal material 202 on a surface layer is removed by chemical mechanical polishing (CMP), so that metal wiring 54 penetrating the transparent insulating films 51A and 51B is formed as illustrated in FIG. 20A.
  • Then, an indium tin oxide (ITO) film 203, for example, is deposited on the transparent insulating film 51B as illustrated in FIG. 20B and is patterned with only a desired region left by lithography, and according to this, a lower electrode 53 a of a normal pixel 2X, a lower electrode 53 c of a phase difference pixel 2PA, and a lower electrode 53 d of a dummy pixel 2DA are formed as illustrated in FIG. 20C.
  • Furthermore, after the transparent insulating film 51C is formed to have a predetermined film thickness on the transparent insulating film 51B including the lower electrodes 53 a, 53 c, and 53 d as illustrated in FIG. 20D, the transparent insulating film 51C is removed by chemical mechanical polishing (CMP), for example, until this has the same film thickness as that of the lower electrode 53 a and the like. As a result, as illustrated in FIG. 21A, the transparent insulating film 51 in FIG. 4 is completed by the remained transparent insulating film 51C and the transparent insulating films 51B and 51A below the same.
  • Subsequently, a photoelectric converting material 204 which performs photoelectric conversion on green wavelength light is formed on upper surfaces of the lower electrodes 53 a, 53 c, and 53 d and the transparent insulating film 51 as illustrated in FIG. 21B, and thereafter, an indium tin oxide (ITO) film 205 is formed thereafter, for example, as illustrated in FIG. 21C.
  • Then, a photoelectric converting film 52 and the upper electrode 53 b shared by the normal pixel 2X, the phase difference pixel 2P, and the dummy pixel 2D are completed as illustrated in FIG. 21D by etching with only a desired region left.
  • Subsequently, as illustrated in FIG. 22A, a highly refractive material 206A of a nitride film and the like serving as a high refractive index layer 56 is formed on upper surfaces of the upper electrode 53 b in a pixel region and the transparent insulating film 51 on an outer peripheral portion of the pixel array unit 3.
  • Thereafter, a contact opening 207 is formed in a place serving as a contact portion of the upper electrode 53 b and a contact opening 208 is formed in a place serving as a contact portion with the conductive plug 122 as illustrated in FIG. 22B.
  • Then, a metal material 209 such as tungsten (W) is conformally deposited on an upper surface of the highly refractive material 206A after the contact openings 207 and 208 are formed as illustrated in FIG. 23A, and thereafter, this is patterned such that only the outer peripheral portion of the pixel array unit 3 is left as illustrated in FIG. 23B, and according to this, connection wiring 124 which connects the conductive plug 122 to the upper electrode 53 b is completed.
  • Then, as illustrated in FIG. 24A, a highly refractive material 206B of the same material as that of the highly refractive material 206A is further formed on the highly refractive material 206A and the connection wiring 124. The stacked highly refractive materials 206A and 206B serve as the high refractive index layer 56.
  • Next, after a resin material 210 being a material of the on-chip lens 57 is further formed on an upper surface of the high refractive index layer 56 as illustrated in FIG. 24B, a photo resist 211 is formed into a lens shape as illustrated in FIG. 25A. Then, the on-chip lens 57 is formed on an uppermost portion of each pixel 2 as illustrated in FIG. 25B by etching back on the basis of the lens-shaped photo resist 211.
  • The pixel 2 of the first embodiment illustrated in FIG. 4 may be manufactured in the above-described manner. Meanwhile, the photoelectric converting unit 61 of the pixel 2 may be similarly manufactured also in the second to sixth embodiments.
  • <Application Example to Electronic Device>
  • Application of the technology of the present disclosure is not limited to that to a solid-state image sensor. That is to say, the technology of the present disclosure is applicable to general electronic devices using the solid-state image sensor as an image capturing unit (photoelectric converting unit) such as an imaging device such as a digital still camera and a video camera, a portable terminal device having an imaging function, and a copying machine using the solid-state image sensor in an image reading unit. The solid-state image sensor may be in a form of a single chip, or may be in a form of a module having the imaging function obtained by packaging an imaging unit, a signal processor, or an optical system.
  • FIG. 26 is a block diagram illustrating a configuration example of the imaging device as the electronic device according to the present disclosure.
  • An imaging device 300 in FIG. 26 is provided with an optical unit 301 formed of a lens group and the like, a solid-state image sensor (imaging device) 302 to which a configuration of the solid-state image sensor 1 in FIG. 1 is adopted, and a digital signal processor (DSP) circuit 303 which is a camera signal processing circuit. The imaging device 300 is also provided with a frame memory 304, a display unit 305, a recording unit 306, an operation unit 307, and a power supply unit 308. The DSP circuit 303, the frame memory 304, the display unit 305, the recording unit 306, the operation unit 307, and the power supply unit 308 are connected to one another through a bus line 309.
  • The optical unit 301 captures incident light (image light) from an object and forms an image on an imaging surface of the solid-state image sensor 302. The solid-state image sensor 302 converts an amount of the incident light the image of which is formed on the imaging surface by the optical unit 301 to an electric signal in pixel unit and outputs the same as a pixel signal. The solid-state image sensor 1 in FIG. 1, that is to say, the solid-state image sensor which includes a pixel structure of the above-described normal pixel 2X, phase difference pixel 2P and the like may be used as the solid-state image sensor 302.
  • The display unit 305 formed of a panel display device such as a liquid crystal panel and an organic electro luminescence (EL) panel, for example, displays a moving image or a still image imaged by the solid-state image sensor 302. The recording unit 306 records the moving image or the still image imaged by the solid-state image sensor 302 in a recording medium such as a hard disk and a semiconductor memory.
  • The operation unit 307 issues an operation command regarding various functions of the imaging device 300 under operation by a user. The power supply unit 308 appropriately supplies various power sources serving as operation power sources of the DSP circuit 303, the frame memory 304, the display unit 305, the recording unit 306, and the operation unit 307 to supply targets.
  • As described above, it is possible to realize the phase difference pixel while avoiding an increase in the number of steps by adopting the solid-state image sensor 1 including the pixel 2 according to the above-described embodiments as the solid-state image sensor 302. Therefore, it is possible to improve a quality of the imaged image also in the imaging device 300 such as the video camera, the digital still camera, and further a camera module for a mobile device such as a cellular phone.
  • The embodiment of the present disclosure is not limited to the above-described embodiments and may be variously changed without departing from the gist of the present disclosure.
  • In the above-described first to third embodiments, the longitudinal direction spectral solid-state image sensor including one photoelectric converting layer (photoelectric converting film 52) above a semiconductor substrate 12 and including two inorganic photoelectric converting layers (photodiodes PD1 and PD2) in the semiconductor substrate 12 is described.
  • However, the technology of the present disclosure is similarly applicable to the longitudinal direction spectral solid-state image sensor including two photoelectric converting layers above the semiconductor substrate 12 and including one inorganic photoelectric converting layer in the semiconductor substrate 12.
  • Also, although it is described that the organic photoelectric converting material is used as the photoelectric converting film 52 of the photoelectric converting unit 61 formed above the semiconductor substrate 12 in the above-described embodiments, it is also possible to adopt an inorganic photoelectric converting material. The inorganic photoelectric converting material includes crystalline silicon, amorphous silicon, and a compound semiconductor such as a Cu—In—Ga—Se compound (CIGS), a Cu—In—Se compound (CIS), a chalcopyrite structure semiconductor, and GaAs, for example.
  • Although the planar size of the lower electrode 53 c of the phase difference pixel 2P is half the size of the lower electrode 53 a of the normal pixel 2X in the above-described embodiments, there is no limitation. It is sufficient that the sensitivities of the photoelectric converting units 61 of the phase difference pixels 2P are asymmetrical with respect to the light incident angle and the photoelectric conversion regions of the phase difference pixels 2PA and 2PB are symmetrical to each other.
  • Furthermore, although the upper electrode 53 b forming the photoelectric converting unit 61 is formed on the entire surface so as to be shared by all the pixels and the lower electrode 53 a is formed for each pixel in the above-described embodiments, it is also possible to form the upper electrode 53 b for each pixel and form the lower electrode 53 a on the entire surface so as to be shared by all the pixels. It is also possible to form both the lower electrode 53 a and the upper electrode 53 b for each pixel.
  • Although the solid-state image sensor in which the first conductivity type is the P-type and the second conductivity type is the N-type, and an electron is used as a signal charge is described in the above-described example, the present disclosure is also applicable to the solid-state image sensor in which a positive hole is used as the signal charge. That is, the first conductivity type may be the N-type, the second conductivity type may be the P-type, and the conductivity types of the above-described respective semiconductor regions may be reversed.
  • Also, the technology of the present disclosure is applicable not only to the solid-state image sensor which senses incident light amount distribution of visible light and images as an image but also to the general solid-state image sensor (physical amount distribution sensing device) such as the solid-state image sensor which images incident amount distribution of infrared rays, X-rays, or particles as an image, or a fingerprint detecting sensor which senses distribution of other physical amounts such as a pressure and capacitance and images as an image in a broad sense.
  • The embodiment of the present disclosure is not limited to the above-described embodiments and may be variously changed without departing from the gist of the present disclosure.
  • For example, it is possible to adopt a combination of all or some of a plurality of embodiments described above.
  • Meanwhile, the effects described in this specification are illustrative only and are not limited; the effects other than those described in this specification may also be included.
  • Meanwhile, the present disclosure may also have the following configuration.
    • (1)
  • A solid-state image sensor including:
  • a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel; and
  • a second pixel including the photoelectric converting unit in which the separated electrode is formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size.
    • (2)
  • The solid-state image sensor according to (1) described above, wherein
  • the third electrode is connected to a charge holding unit which holds a charge generated by the photoelectric converting unit.
    • (3)
  • The solid-state image sensor according to (1) or (2) described above, wherein
  • the third electrode is the separated electrode of an adjacent pixel.
    • (4)
  • The solid-state image sensor according to (1) or (2) described above, wherein
  • the third electrode lies across three pixels including the second pixel and an adjacent pixel.
    • (5)
  • The solid-state image sensor according to (1) described above, wherein
  • the third electrode is connected to wiring which supplies fixed potential.
    • (6)
  • The solid-state image sensor according to (1) or (5) described above, wherein
  • the third electrode is an element separating electrode formed between separated electrodes of adjacent pixels.
    • (7)
  • The solid-state image sensor according to (1) described above, wherein
  • the third electrode is an isolated pattern which is not connected to wiring.
    • (8)
  • The solid-state image sensor according to any one of (1) to (7) described above, wherein
  • the second pixel is a phase difference pixel which generates a signal for detecting a focal point.
    • (9)
  • The solid-state image sensor according to any one of (1) to (8) described above, wherein
  • the photoelectric converting film is a film which performs photoelectric conversion on light of a wavelength of a predetermined color.
    • (10)
  • The solid-state image sensor according to (9) described above, wherein
  • the photoelectric converting film is a film which performs the photoelectric conversion on green wavelength light.
    • (11)
  • The solid-state image sensor according to any one of (1) to (10) described above, wherein
  • the second pixel is further provided with an inorganic photoelectric converting unit in a semiconductor substrate, and
  • the inorganic photoelectric converting unit performs the photoelectric conversion on light of a wavelength which is not subjected to the photoelectric conversion by the photoelectric converting unit.
    • (12)
  • The solid-state image sensor according to any one of (1) to (7) described above, wherein
  • the photoelectric converting film is a film capable of performing photoelectric conversion on light of wavelengths of red, green, and blue.
    • (13)
  • The solid-state image sensor according to (12) described above, wherein
  • a red, green, or blue color filter is arranged above the photoelectric converting film, and
  • the photoelectric converting film performs the photoelectric conversion on light which passes through the color filter.
    • (14)
  • A method of manufacturing a solid-state image sensor including:
  • forming a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel, and
  • a second pixel including the photoelectric converting unit in which the separated electrode is formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size.
    • (15)
  • An electronic device including:
  • a solid-state image sensor including:
  • a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes which interpose the photoelectric converting film from above and below in which at least one of the first and second electrodes is a separated electrode separated for each pixel; and
  • a second pixel including the photoelectric converting unit in which the separated electrode is formed to have a planar size smaller than the planar size of the separated electrode of the first pixel and a third electrode extending at least to a boundary of the pixel is formed in a region which is vacant due to a smaller planar size.
    • REFERENCE SIGNS LIST
    • 1 Solid-state image sensor
    • 2 Pixel
    • 2X Normal pixel
    • 2P Phase difference pixel
    • 2D Dummy pixel
    • 3 Pixel array unit
    • 12 Semiconductor substrate
    • PD1, PD2 Photodiode
    • 41 to 43 Semiconductor region
    • 49 FD unit
    • 52 Photoelectric converting film
    • 53 a Lower electrode
    • 53 b Upper electrode
    • 53 c, 53 d Lower electrode
    • 54 Metal wiring
    • 56 High refractive index layer
    • 57 On-chip lens
    • 61 Photoelectric converting unit
    • 81 Element separating electrode
    • 82 Metal wiring
    • 83 Element separating electrode
    • 91 Photoelectric converting film
    • 92 Color filter
    • 300 Imaging device
    • 302 Solid-state image sensor

Claims (20)

1. A solid-state image sensor comprising:
a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes, wherein the first and second electrodes sandwich the photoelectric converting film from below and above, respectively, wherein the first electrode is a separated electrode that includes a first portion overlapping the first pixel; and
a second pixel including the photoelectric converting unit, wherein a second portion of the separated electrode that overlaps the second pixel is formed to have a planar size smaller than a planar size of the separated electrode of the first pixel, the second pixel including the first portion of the separated electrode extending to a region of the second pixel which is vacant due to the smaller planar size of the second portion of the separated electrode.
2. The solid-state image sensor according to claim 1, wherein the first portion of the separated electrode is connected to wiring which supplies a fixed potential.
3. The solid-state image sensor according to claim 1, wherein the first portion of the separated electrode is an isolated pattern which is not connected to wiring.
4. The solid-state image sensor according to claim 1, wherein the first pixel and the second pixel are adjacent to one another in a row direction.
5. The solid-state image sensor according to claim 1, wherein the first pixel and the second pixel are diagonally adjacent to one another.
6. The solid-state image sensor according to claim 1, wherein a third portion of the separated electrode extends between the first and second pixels and at least one other pixel.
7. The solid-state image sensor according to claim 1, wherein the second electrode is a contiguous electrode that overlaps the first and second pixels.
8. The solid-state image sensor according to claim 1, wherein the first portion of the separated electrode overlaps a boundary between the first pixel and the second pixel and a boundary between the second pixel and a third pixel.
9. The solid-state image sensor according to claim 8, wherein the first pixel, the second pixel, and the third pixel are adjacent to one another in a row direction.
10. The solid-state image sensor according to claim 9, wherein the first portion of the separated electrode is electrically connected to a floating diffusion region.
11. An imaging device, comprising:
a solid-state image sensor including:
a first pixel including a photoelectric converting unit formed of a photoelectric converting film and first and second electrodes, wherein the first and second electrodes sandwich the photoelectric converting film from below and above, respectively, wherein the first electrode is a separated electrode that includes a first portion overlapping the first pixel; and
a second pixel including the photoelectric converting unit, wherein a second portion of the separated electrode that overlaps the second pixel is formed to have a planar size smaller than a planar size of the separated electrode of the first pixel, the second pixel including the first portion of the separated electrode extending to a region of the second pixel which is vacant due to the smaller planar size of the second portion of the separated electrode.
12. The imaging device according to claim 11, wherein the first portion of the separated electrode is connected to wiring which supplies a fixed potential.
13. The imaging device according to claim 11, wherein the first portion of the separated electrode is an isolated pattern which is not connected to wiring.
14. The imaging device according to claim 11, wherein the first pixel and the second pixel are adjacent to one another in a row direction.
15. The imaging device according to claim 11, wherein the first pixel and the second pixel are diagonally adjacent to one another.
16. The imaging device according to claim 11, wherein a third portion of the separated electrode extends between the first and second pixels and at least one other pixel.
17. The imaging device according to claim 11, wherein the second electrode is a contiguous electrode that overlaps the first and second pixels.
18. The imaging device according to claim 11, wherein the first portion of the separated electrode overlaps a boundary between the first pixel and the second pixel and a boundary between the second pixel and a third pixel.
19. The imaging device according to claim 18, wherein the first pixel, the second pixel, and the third pixel are adjacent to one another in a row direction.
20. The imaging device according to claim 19, wherein the first portion of the separated electrode is electrically connected to a floating diffusion region.
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Families Citing this family (38)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI788994B (en) * 2014-11-05 2023-01-01 日商索尼半導體解決方案公司 Solid-state imaging element, manufacturing method thereof, and electronic device
US20160181309A1 (en) * 2014-12-22 2016-06-23 Canon Kabushiki Kaisha Microlens and method of manufacturing microlens
WO2016115338A1 (en) 2015-01-14 2016-07-21 Emanuele Mandelli Phase-detect autofocus
WO2016121521A1 (en) 2015-01-29 2016-08-04 ソニー株式会社 Solid-state imaging element and electronic device
JP6595804B2 (en) * 2015-05-27 2019-10-23 ソニーセミコンダクタソリューションズ株式会社 Solid-state imaging device and imaging apparatus
JP6706482B2 (en) 2015-11-05 2020-06-10 ソニーセミコンダクタソリューションズ株式会社 Solid-state imaging device and electronic device
US10063763B2 (en) 2016-07-07 2018-08-28 Tdk Taiwan Corp. Camera module
US11251218B2 (en) * 2016-10-20 2022-02-15 Invisage Technologies, Inc. Image sensors with enhanced wide-angle performance
WO2018075581A1 (en) 2016-10-20 2018-04-26 Invisage Technologies, Inc. Noise mitigation in image sensors with selectable row readout
JP6857341B2 (en) * 2016-12-22 2021-04-14 株式会社シグマ Imaging device and signal processing method
KR102549541B1 (en) 2017-01-11 2023-06-29 삼성전자주식회사 Image sensors
KR102652981B1 (en) * 2017-01-16 2024-04-02 삼성전자주식회사 Image sensor
JP7187440B2 (en) * 2017-03-31 2022-12-12 ソニーセミコンダクタソリューションズ株式会社 Solid-state imaging device, electronic device, and manufacturing method
JP7026336B2 (en) * 2017-06-06 2022-02-28 パナソニックＩｐマネジメント株式会社 Imaging device and camera system
KR20190012812A (en) * 2017-07-28 2019-02-11 에스케이하이닉스 주식회사 Image sensor having phase difference detection pixel
JP2019041142A (en) * 2017-08-22 2019-03-14 ソニーセミコンダクタソリューションズ株式会社 Solid-state imaging device, manufacturing method of solid-state imaging device, and electronic apparatus
JP2019040897A (en) 2017-08-22 2019-03-14 ソニーセミコンダクタソリューションズ株式会社 Solid state imaging device and electronic equipment
DE112018004434T5 (en) * 2017-10-04 2020-05-20 Sony Semiconductor Solutions Corporation SOLID IMAGING ELEMENT AND ELECTRONIC DEVICE
CN107919374A (en) * 2017-12-15 2018-04-17 德淮半导体有限公司 A kind of imaging sensor and forming method thereof
JP2019133982A (en) * 2018-01-29 2019-08-08 キヤノン株式会社 Imaging apparatus, imaging system, and mobile body
JP2019165136A (en) * 2018-03-20 2019-09-26 ソニーセミコンダクタソリューションズ株式会社 Solid state imaging device, manufacturing method therefor, and electronic apparatus
EP3806153A4 (en) * 2018-06-05 2021-07-21 Sony Semiconductor Solutions Corporation Imaging device
KR20210018238A (en) * 2018-06-06 2021-02-17 소니 세미컨덕터 솔루션즈 가부시키가이샤 Imaging device, electronic device
CN112369011B (en) * 2018-07-03 2024-04-19 索尼半导体解决方案公司 Solid-state image pickup device
JP2020016681A (en) * 2018-07-23 2020-01-30 セイコーエプソン株式会社 Liquid crystal device, method for driving liquid crystal device, and electronic apparatus
KR102553314B1 (en) * 2018-08-29 2023-07-10 삼성전자주식회사 Image sensor
CN111582010B (en) * 2019-02-19 2023-10-03 群创光电股份有限公司 Method for enabling electronic device to receive fingerprint data and related electronic device
WO2020179282A1 (en) * 2019-03-06 2020-09-10 パナソニックＩｐマネジメント株式会社 Light detection device, light detection system, and filter array
US11297219B2 (en) 2019-06-11 2022-04-05 Samsung Electronics Co., Ltd. Image sensor
JPWO2021014849A1 (en) * 2019-07-24 2021-01-28
KR20210047483A (en) * 2019-10-22 2021-04-30 에스케이하이닉스 주식회사 Image sensor for supporting plural capturing modes
JP2021141552A (en) * 2020-03-09 2021-09-16 キヤノン株式会社 Image pickup device, imaging apparatus, computer program, and storage medium
JP2021190483A (en) * 2020-05-26 2021-12-13 株式会社ジャパンディスプレイ Detection device
JP2022000873A (en) * 2020-06-19 2022-01-04 ソニーセミコンダクタソリューションズ株式会社 Solid state imaging device
US11728362B2 (en) * 2021-04-22 2023-08-15 Taiwan Semiconductor Manufacturing Company Ltd Image sensor pixel and metal shielding of charge storage device of image sensor pixel formed by one step process
US20230029820A1 (en) * 2021-08-02 2023-02-02 Visera Technologies Company Limited Image sensor and method of forming the same
US20230110102A1 (en) * 2021-10-07 2023-04-13 Visera Technologies Company Limited Solid-state image sensor
TWI792651B (en) * 2021-11-01 2023-02-11 友達光電股份有限公司 Photosensitive device

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150195466A1 (en) * 2013-06-24 2015-07-09 Panasonic Intellectual Property Management Co., Ltd. Solid-state imaging device
US20150255498A1 (en) * 2014-03-04 2015-09-10 Kabushiki Kaisha Toshiba Solid-state imaging device

Family Cites Families (30)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60123059A (en) * 1983-12-08 1985-07-01 Toshiba Corp Adhesion type color image sensor
JPH0258381A (en) * 1988-08-24 1990-02-27 Hitachi Ltd Photoelectric conversion element and line image sensor
JPH10115552A (en) * 1996-08-19 1998-05-06 Hamamatsu Photonics Kk Optical detector and solid-state image sensing device
JPH1197664A (en) * 1997-09-20 1999-04-09 Semiconductor Energy Lab Co Ltd Electronic apparatus and manufacture thereof
JP2001284562A (en) 2000-03-30 2001-10-12 Toshiba Corp Array substrate for x-ray detector and inspecting method therefor
US8848047B2 (en) * 2006-09-28 2014-09-30 Fujifilm Corporation Imaging device and endoscopic apparatus
JP4961590B2 (en) 2007-04-13 2012-06-27 力晶科技股▲ふん▼有限公司 Image sensor and manufacturing method thereof
WO2008132812A1 (en) * 2007-04-20 2008-11-06 Nikon Corporation Solid-state imaging element and imaging device using same
JP5040458B2 (en) * 2007-06-16 2012-10-03 株式会社ニコン Solid-state imaging device and imaging apparatus using the same
JP5359465B2 (en) * 2009-03-31 2013-12-04 ソニー株式会社 Solid-state imaging device, signal processing method for solid-state imaging device, and imaging device
JP5564847B2 (en) * 2009-07-23 2014-08-06 ソニー株式会社 SOLID-STATE IMAGING DEVICE, ITS MANUFACTURING METHOD, AND ELECTRONIC DEVICE
JP5537905B2 (en) 2009-11-10 2014-07-02 富士フイルム株式会社 Imaging device and imaging apparatus
JP2011210748A (en) * 2010-03-26 2011-10-20 Fujifilm Corp Ccd type solid-state imaging element and method of manufacturing the same, and imaging device
JP2011216701A (en) * 2010-03-31 2011-10-27 Sony Corp Solid-state imaging apparatus and electronic device
JP4779054B1 (en) * 2010-03-31 2011-09-21 富士フイルム株式会社 Solid-state imaging device and imaging apparatus
JP5651986B2 (en) * 2010-04-02 2015-01-14 ソニー株式会社 SOLID-STATE IMAGING DEVICE, ITS MANUFACTURING METHOD, ELECTRONIC DEVICE, AND CAMERA MODULE
JP2011249445A (en) * 2010-05-25 2011-12-08 Fujifilm Corp Solid state imaging device manufacturing method
US8908070B2 (en) * 2010-06-18 2014-12-09 Fujifilm Corporation Solid state imaging device and digital camera
JP5693082B2 (en) 2010-08-09 2015-04-01 キヤノン株式会社 Imaging device
JP2014029351A (en) * 2010-11-18 2014-02-13 Fujifilm Corp Solid state imaging element and imaging apparatus
JP5682327B2 (en) * 2011-01-25 2015-03-11 ソニー株式会社 Solid-state imaging device, manufacturing method of solid-state imaging device, and electronic apparatus
CN103460703B (en) 2011-03-24 2015-03-11 富士胶片株式会社 Color image capturing element and image capturing device
JP5466338B2 (en) * 2011-03-31 2014-04-09 富士フイルム株式会社 Solid-state imaging device and method for manufacturing solid-state imaging device
JP5556823B2 (en) 2012-01-13 2014-07-23 株式会社ニコン Solid-state imaging device and electronic camera
KR102221993B1 (en) * 2012-01-23 2021-03-02 소니 주식회사 Solid-state image pickup apparatus, method for manufacturing same, and electronic apparatus
JP2014067948A (en) * 2012-09-27 2014-04-17 Fujifilm Corp Solid-state imaging device and imaging apparatus
TWI636557B (en) * 2013-03-15 2018-09-21 新力股份有限公司 Solid-state imaging device, manufacturing method thereof, and electronic device
JP6108172B2 (en) * 2013-09-02 2017-04-05 ソニー株式会社 Solid-state imaging device, manufacturing method thereof, and electronic device
KR102328769B1 (en) * 2014-06-20 2021-11-18 삼성전자주식회사 Image sensor and image processing system including the same
TWI788994B (en) * 2014-11-05 2023-01-01 日商索尼半導體解決方案公司 Solid-state imaging element, manufacturing method thereof, and electronic device

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150195466A1 (en) * 2013-06-24 2015-07-09 Panasonic Intellectual Property Management Co., Ltd. Solid-state imaging device
US20150255498A1 (en) * 2014-03-04 2015-09-10 Kabushiki Kaisha Toshiba Solid-state imaging device

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