WO2022130987A1 - Solid-state imaging device and method for manufacturing same - Google Patents

Solid-state imaging device and method for manufacturing same Download PDF

Info

Publication number
WO2022130987A1
WO2022130987A1 PCT/JP2021/044167 JP2021044167W WO2022130987A1 WO 2022130987 A1 WO2022130987 A1 WO 2022130987A1 JP 2021044167 W JP2021044167 W JP 2021044167W WO 2022130987 A1 WO2022130987 A1 WO 2022130987A1
Authority
WO
WIPO (PCT)
Prior art keywords
light
substrate
shielding film
groove
solid
Prior art date
Application number
PCT/JP2021/044167
Other languages
French (fr)
Japanese (ja)
Inventor
佳之 長濱
Original Assignee
ソニーセミコンダクタソリューションズ株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ソニーセミコンダクタソリューションズ株式会社 filed Critical ソニーセミコンダクタソリューションズ株式会社
Publication of WO2022130987A1 publication Critical patent/WO2022130987A1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
    • H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
    • H01L27/144—Devices controlled by radiation
    • H01L27/146—Imager structures

Definitions

  • This disclosure relates to a solid-state image sensor and a method for manufacturing the same.
  • the solid-state image sensor includes a photoelectric conversion unit and a memory unit in the substrate
  • a groove is provided between the photoelectric conversion unit and the memory unit.
  • This groove may include a penetrating portion that penetrates the substrate and a non-penetrating portion that does not penetrate the substrate.
  • the penetrating portion is provided, for example, in order to prevent light from entering the memory portion.
  • the non-penetrating portion is provided, for example, to secure a path for transferring charges from the photoelectric conversion unit to the memory unit.
  • a light-shielding film is generally embedded in the penetrating portion and the non-penetrating portion.
  • the present disclosure provides a solid-state image sensor capable of forming a suitable light-shielding film and a method for manufacturing the same.
  • the solid-state imaging device on the first side surface of the present disclosure includes a substrate having a first surface opposite to the light incident surface, a second surface serving as the light incident surface, and a first surface provided in the substrate.
  • a first pixel having a photoelectric conversion unit and a first charge storage unit, and a second pixel having a second photoelectric conversion unit and a second charge storage unit provided in the substrate are adjacent to each other in the substrate.
  • the first light-shielding film provided between the second photoelectric conversion unit and the first charge storage unit, the multilayer wiring layer provided on the first surface side of the substrate, and the multilayer wiring layer. It is provided with a second light-shielding film that is provided and is in contact with the first light-shielding film.
  • the solid-state image sensor on the first side surface is provided on the second surface of the substrate, overlaps the first charge storage portion in a plan view, and is in contact with the first light-shielding film.
  • a light-shielding film may be further provided. As a result, for example, it is possible to suppress the formation of a gap between the first light-shielding film and the third light-shielding film, and it is possible to form a suitable light-shielding film.
  • the width of the first light-shielding film may be narrowed as it progresses from the first surface side to the second surface side. This makes it possible to form a first light-shielding film in the substrate from the first surface side of the substrate, for example.
  • the multilayer wiring layer includes an insulating layer provided on the first surface of the substrate, and the first light-shielding film is provided in the substrate and in the insulating layer. You may. Thereby, for example, by forming the first light-shielding film penetrating the substrate and the insulating layer, it is possible to suppress the formation of a gap between the first light-shielding film and the second light-shielding film.
  • the insulating film may function as a gate insulating film of a transistor.
  • the insulating film may function as a gate insulating film of a transistor.
  • the second light-shielding film may be in contact with the first light-shielding film and the electrode layer of the transistor.
  • the second light-shielding film by forming the second light-shielding film so as to cover the first light-shielding film and the electrode layer, it is possible to suppress the formation of a gap between the first light-shielding film and the second light-shielding film. ..
  • the first light-shielding film may be provided in the first groove penetrating the substrate. This makes it possible to form the first light-shielding film in the substrate, for example, by embedding the first light-shielding film in the first groove.
  • the width of the first groove may be narrowed as it progresses from the first surface side to the second surface side. This makes it possible to form a first groove in the substrate from the first surface side of the substrate, for example.
  • the third light-shielding film may be provided on the second surface of the substrate and in the second groove that does not penetrate the substrate. This makes it possible, for example, to prevent light from entering the charge storage unit from the photoelectric conversion unit by the first light-shielding film and the third light-shielding film.
  • the width of the second groove may be widened from the first surface side to the second surface side. This makes it possible to form, for example, a second groove in the substrate from the second surface side of the substrate.
  • the solid-state imaging device on the second side of the present disclosure includes a substrate having a first surface opposite to the light incident surface, a second surface serving as the light incident surface, and a first surface provided in the substrate. It penetrates the first pixel having a photoelectric conversion unit and a first charge storage unit, a second pixel having a second photoelectric conversion unit and a second charge storage unit provided in the substrate, and the substrate. A first groove provided between the adjacent second photoelectric conversion unit and the first charge storage unit, the first portion provided on the first surface side in the substrate, and the said.
  • a first groove including a second portion provided on the second surface side in the substrate, a first light-shielding film provided in the first portion, and a first light-shielding film provided on the first surface side of the substrate. It includes a multi-layer wiring layer and a second light-shielding film provided in the multi-layer wiring layer and in contact with the first light-shielding film. As a result, for example, it is possible to suppress the formation of a gap between the first light-shielding film and the second light-shielding film, and it is possible to form a suitable light-shielding film.
  • the width of the first portion becomes narrower from the first surface side to the second surface side, and the width of the second portion is from the first surface side. It may become wider as it goes to the second surface side. This makes it possible to form a first groove in the substrate from the first surface side and the second surface side of the substrate, for example.
  • the solid-state image sensor on the second side surface is provided on the second surface of the substrate and in the second portion, and is overlapped with the first charge storage portion in a plan view. May be further provided. This makes it possible, for example, to form a first light-shielding film in the first groove from the first surface side of the substrate and to form a third light-shielding film in the first groove from the second surface side of the substrate.
  • the third light-shielding film may be further provided in a second groove that does not penetrate the substrate. This makes it possible, for example, to prevent light from entering the charge storage unit from the photoelectric conversion unit by the first light-shielding film and the third light-shielding film.
  • the width of the second groove may become wider as it progresses from the first surface side to the second surface side. This makes it possible to form, for example, a second groove in the substrate from the second surface side of the substrate.
  • the first groove and the second groove may be connected to each other in the substrate. This makes it possible to suppress light from entering the charge storage portion from the gap between the first light-shielding film in the first groove and the third light-shielding film in the second groove, for example.
  • a substrate having a first surface opposite to the light incident surface and a second surface to be the light incident surface is prepared, and the substrate is provided in the substrate.
  • a first pixel having a first photoelectric conversion unit and a first charge storage unit is formed, a second pixel having a second photoelectric conversion unit and a second charge storage unit is formed in the substrate, and a second pixel having a second photoelectric conversion unit and a second charge storage unit is formed in the substrate.
  • a first light-shielding film is formed between the adjacent second photoelectric conversion unit and the first charge storage unit, a multilayer wiring layer is formed on the first surface side of the substrate, and the inside of the multilayer wiring layer is formed.
  • the method for manufacturing the solid-state image sensor on the third side surface further includes forming a first groove penetrating the substrate, and the first light-shielding film is the first from the first surface side of the substrate. It may be formed in one groove. This makes it possible to form the first light-shielding film in the substrate, for example, by embedding the first light-shielding film in the first groove.
  • a third light-shielding film that overlaps the first charge storage portion in a plan view and is in contact with the first light-shielding film is formed on the second surface of the substrate. It may further include forming. As a result, for example, it is possible to suppress the formation of a gap between the first light-shielding film and the third light-shielding film, and it is possible to form a suitable light-shielding film.
  • the method for manufacturing the solid-state imaging device on the third side surface further includes forming a second groove that does not penetrate the substrate, and the third light-shielding film is formed on the second surface of the substrate. Moreover, it may be formed in the second groove from the second surface side of the substrate. This makes it possible, for example, to prevent light from entering the charge storage unit from the photoelectric conversion unit by the first light-shielding film and the third light-shielding film.
  • FIG. 1 It is a top view which shows the specific example of the setting position of the image pickup part of FIG. It is a figure which shows an example of the schematic structure of an endoscopic surgery system. It is a block diagram which shows an example of the functional structure of a camera head and a CCU.
  • FIG. 1 is a block diagram showing a configuration of a solid-state image sensor according to the first embodiment.
  • the solid-state image sensor of FIG. 1 is a CMOS (Complementary Metal Oxide Semiconductor) type image sensor, which includes a pixel array region 2 having a plurality of pixels 1, a control circuit 3, a vertical drive circuit 4, and a plurality of column signal processes. It includes a circuit 5, a horizontal drive circuit 6, an output circuit 7, a plurality of vertical signal lines 8, and a horizontal signal line 9.
  • CMOS Complementary Metal Oxide Semiconductor
  • Each pixel 1 includes a photodiode that functions as a photoelectric conversion unit and a MOS transistor that functions as a pixel transistor.
  • Examples of pixel transistors are transfer transistors, reset transistors, amplification transistors, selection transistors, and the like. These pixel transistors may be shared by some pixels 1.
  • the pixel array area 2 has a plurality of pixels 1 arranged in a two-dimensional array.
  • the pixel array region 2 is an effective pixel region that receives light and performs photoelectric conversion to amplify and output the signal charge generated by the photoelectric conversion, and a black reference pixel that outputs optical black as a reference for the black level. Includes areas and.
  • the black reference pixel region is arranged on the outer peripheral portion of the effective pixel region.
  • the control circuit 3 generates various signals that serve as reference for the operation of the vertical drive circuit 4, the column signal processing circuit 5, the horizontal drive circuit 6, etc., based on the vertical sync signal, the horizontal sync signal, the master clock, and the like.
  • the signal generated by the control circuit 3 is, for example, a clock signal or a control signal, and is input to the vertical drive circuit 4, the column signal processing circuit 5, the horizontal drive circuit 6, and the like.
  • the vertical drive circuit 4 includes, for example, a shift register, and scans each pixel 1 in the pixel array area 2 in a row unit in the vertical direction.
  • the vertical drive circuit 4 further supplies a pixel signal based on the signal charge generated by each pixel 1 to the column signal processing circuit 5 through the vertical signal line 8.
  • the column signal processing circuit 5 is arranged, for example, for each column of the pixel 1 in the pixel array area 2, and the signal processing of the signal output from the pixel 1 for one row is based on the signal from the black reference pixel area. Do it for each row. Examples of this signal processing are denoising and signal amplification.
  • the horizontal drive circuit 6 includes, for example, a shift register, and supplies pixel signals from each column signal processing circuit 5 to the horizontal signal line 9.
  • the output circuit 7 performs signal processing on the signal supplied from each column signal processing circuit 5 through the horizontal signal line 9, and outputs the signal to which this signal processing has been performed.
  • FIG. 2 is a cross-sectional view showing the structure of the solid-state image sensor of the first embodiment.
  • FIG. 2 shows a vertical cross section of the pixel array region 2 of FIG. 1, specifically, shows a vertical cross section of three pixels 1 in the pixel array region 2.
  • These pixels 1 are examples of the first pixel and the second pixel of the present disclosure.
  • the solid-state imaging device of the present embodiment includes a substrate 11, a plurality of photoelectric conversion units 12, a p + type semiconductor region 13, an n-type semiconductor region 14, and a p-type semiconductor region 15 included in each photoelectric conversion unit 12. It includes a plurality of memory units 16, a p + type semiconductor region 17, an n ⁇ type semiconductor region 18, and a p-type semiconductor region 19 included in each memory unit 16, and another semiconductor region 20 in the substrate 11.
  • These photoelectric conversion units 12 are examples of the first photoelectric conversion unit and the second photoelectric conversion unit of the present disclosure.
  • these memory units 16 are examples of the first charge storage unit and the second charge storage unit of the present disclosure.
  • the solid-state image pickup device of the present embodiment further includes a plurality of grooves 21, an insulating film 22 and a light-shielding film 23 provided in each groove 21, and a plurality of grooves 24 (FIG. 2 shows one of them).
  • a first insulating film 25, a second insulating film 26, and a light-shielding film 27 provided in each groove 24 or the like, a flattening film 28, a plurality of color filters 29, and a plurality of on-chip lenses 30 are provided.
  • the groove 21 is an example of the first groove of the present disclosure
  • the groove 24 is an example of the second groove of the present disclosure.
  • the light-shielding film 23 is an example of the first light-shielding film of the present disclosure
  • the light-shielding film 27 is an example of the third light-shielding film of the present disclosure.
  • the solid-state imaging device of the present embodiment further includes an insulating layer 31 that functions as a gate insulating film, an interlayer insulating film 32, an electrode layer 33 that functions as a gate electrode, and a light-shielding film 34 provided in the vicinity of each groove 21.
  • a plurality of contact plugs 35, a plurality of wiring layers 36, 37, 38, 39, a plurality of via plugs 40, and a support substrate 41 are provided.
  • the light-shielding film 34 is an example of the second light-shielding film of the present disclosure.
  • the layer 42 including the insulating layer 31, the interlayer insulating film 32, the electrode layer 33, the light-shielding film 34, the contact plug 35, the wiring layers 36 to 39, and the via plug 40 is an example of the multilayer wiring layer of the present disclosure.
  • FIG. 2 shows the X-axis, Y-axis, and Z-axis that are perpendicular to each other.
  • the X and Y directions correspond to the horizontal direction (horizontal direction), and the Z direction corresponds to the vertical direction (vertical direction). Further, the + Z direction corresponds to the upward direction, and the ⁇ Z direction corresponds to the downward direction.
  • the ⁇ Z direction may or may not exactly coincide with the direction of gravity.
  • FIG. 3 is an enlarged cross-sectional view showing the structure of the solid-state image sensor of the first embodiment.
  • the substrate 11 is, for example, a semiconductor substrate such as a silicon (Si) substrate.
  • FIG. 2 shows the front surface S1 and the back surface S2 of the substrate 11.
  • the front surface S1 of the substrate 11 is a surface (lower surface) in the ⁇ Z direction of the substrate 11
  • the back surface S2 of the substrate 11 is a surface (upper surface) in the + Z direction of the substrate 11. Since the solid-state image sensor of this embodiment is a back-illuminated type, the back surface S2 of the substrate 11 is the light incident surface (light receiving surface) of the substrate 11.
  • the front surface S1 of the substrate 11 is an example of the first surface of the present disclosure
  • the back surface S2 of the substrate 11 is an example of the second surface of the present disclosure.
  • the photoelectric conversion unit 12 is provided in the substrate 11 for each pixel 1.
  • Each photoelectric conversion unit 12 includes a p + type semiconductor region 13 formed in the substrate 11 in order from the front surface S1 side to the back surface S2 side of the substrate 11, an n ⁇ type semiconductor region 14, and a p-type semiconductor region 15. ing.
  • a photodiode is realized by a pn junction between the p + type semiconductor region 13 and the n-type semiconductor region 14 and a pn junction between the n-type semiconductor region 14 and the p-type semiconductor region 15. And the photodiode converts light into a charge.
  • the photoelectric conversion unit 12 receives light from the back surface S2 side of the substrate 11, generates a signal charge according to the amount of the received light, and stores the generated signal charge in the n-type semiconductor region 14.
  • the memory unit 16 is also provided in the substrate 11 for each pixel 1.
  • Each memory unit 16 includes a p + type semiconductor region 17 formed in the substrate 11 in order from the front surface S1 side to the back surface S2 side of the substrate 11, an n ⁇ type semiconductor region 18, and a p-type semiconductor region 19. There is. However, the total thickness of the p + type semiconductor region 17, the n-type semiconductor region 18, and the p-type semiconductor region 19 in the Z direction is the Z of the p + type semiconductor region 13, the n-type semiconductor region 14, and the p-type semiconductor region 15. It is thinner than the total thickness in the direction.
  • the memory unit 16 in each pixel 1 accumulates the signal charge transferred from the photoelectric conversion unit 12 in the same pixel 1.
  • the other semiconductor region 20 in the substrate 11 includes, for example, a floating diffusion portion FD described later (see FIG. 16).
  • the groove 21 is provided in the substrate 11 and the insulating layer 31, and penetrates the substrate 11 and the insulating layer 31.
  • Each groove 21 is provided in the substrate 11 between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other.
  • Each groove 21 shown in FIG. 2 is provided between the photoelectric conversion unit 12 and the memory unit 16 in different pixels 1, but each groove 21 of the present embodiment has the photoelectric conversion unit 12 in the same pixel 1. It may be provided between the memory unit 16 and the memory unit 16.
  • the groove 21 is formed, for example, by forming a recess in the substrate 11 from the surface S1 side of the substrate 11 by dry etching. Therefore, the width of the groove 21 of the present embodiment in the X direction becomes narrower from the front surface S1 side to the back surface S2 side of the substrate.
  • the groove 21 of the present embodiment has a shape extending in the Y direction and the Z direction.
  • the insulating film 22 and the light-shielding film 23 are sequentially formed in each groove 21. Specifically, the insulating film 22 is formed on the side surface of the substrate 11 and the insulating layer 31 in each groove 21, and the light-shielding film 23 is embedded in each groove 21 via the insulating film 22.
  • the insulating film 22 is, for example, a silicon oxide film (SiO 2 film) formed by oxidizing the substrate 11 and the insulating layer 31.
  • the light-shielding film 23 is a film containing a metal element such as tungsten (W), aluminum (Al), or copper (Cu), and has an effect of blocking light.
  • the shape of the light-shielding film 23 of this embodiment is almost the same as the shape of the groove 21. Therefore, the width of the light-shielding film 23 of the present embodiment in the X direction becomes narrower from the front surface S1 side to the back surface S2 side of the substrate. Further, the light-shielding film 23 of the present embodiment has a shape extending in the Y direction and the Z direction.
  • the reference numeral W shown in FIG. 2 indicates the width of the light-shielding film 23 in the X direction.
  • the shapes of the groove 21, the insulating film 22, and the light-shielding film 23 are also shown in FIG. FIG.
  • FIG 3 shows, as an example of the width W of the light-shielding film 23, the width W1 of the light-shielding film 23 near the lower end of the light-shielding film 23 and the width W2 of the light-shielding film 23 near the upper end of the light-shielding film 23 (W2 ⁇ . W1).
  • the groove 24 is provided in the substrate 11 and does not penetrate the substrate 11. Each groove 24 is provided in the substrate 11 between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other.
  • the groove 24 shown in FIG. 2 is provided between the photoelectric conversion unit 12 and the memory unit 16 in the same pixel 1, but each groove 24 of the present embodiment has a photoelectric conversion unit 12 in different pixels 1. It may be provided between the memory unit 16 and the memory unit 16.
  • the groove 24 is formed, for example, by forming a recess in the substrate 11 from the back surface S2 side of the substrate 11 by dry etching. Therefore, the width of the groove 24 of the present embodiment in the X direction becomes wider from the front surface S1 side to the back surface S2 side of the substrate.
  • the groove 24 of the present embodiment has a shape extending in the Y direction and the Z direction. When forming the groove 24, for example, the groove 24 is formed from the back surface side S2 of the substrate 11 into the substrate 11 by the above-mentioned dry etching so as not to penetrate the substrate 11.
  • the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are sequentially formed in the back surface S2 of the substrate 11 and in each groove 24 of the substrate 11. Specifically, the first insulating film 25 and the second insulating film 26 are sequentially formed on the side surface and the bottom surface of the substrate 11 in each groove 24, and the light-shielding film 27 is a first insulating film in each groove 24. It is embedded via the 25 and the second insulating film 26. Further, the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are sequentially laminated on the back surface S2 of the substrate 11 outside the groove 24.
  • the first insulating film 25 and the second insulating film 26 have an opening on the light-shielding film 23, and the light-shielding film 27 is embedded in the opening. Therefore, the light-shielding film 27 is in contact with the light-shielding film 23 within this opening.
  • the shapes of the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are also shown in FIG.
  • the first insulating film 25 is, for example, a fixed charge film having a negative fixed charge.
  • the fixed charge film has an effect of suppressing the generation of noise called dark current due to minute defects existing at the interface of the substrate 11.
  • the fixed charge film is, for example, an oxide film or a nitride film containing a metal element such as hafnium (Hf), aluminum (Al), zirconium (Zr), tantalum (Ta), or titanium (Ti).
  • the second insulating film 26 is, for example, a silicon oxide film (SiO 2 film), a silicon nitride film (SiN film), a silicon nitride film (SiON film), or a resin film.
  • the first insulating film 25 and the second insulating film 26 are formed by, for example, ALD (Atomic Layer Deposition).
  • the light-shielding film 27 is a film containing a metal element such as tungsten (W), aluminum (Al), or copper (Cu), and has an effect of blocking light.
  • the shape of the light-shielding film 27 in the groove 24 of the present embodiment is substantially the same as the shape of the groove 24. Therefore, the width of the light-shielding film 27 of the present embodiment in the X direction becomes wider from the front surface S1 side to the back surface S2 side of the substrate. Further, the light-shielding film 27 of the present embodiment has a shape extending in the Y direction and the Z direction. On the other hand, the light-shielding film 27 outside the groove 24 of the present embodiment is provided at a position where it overlaps with the memory unit 16 in a plan view.
  • the flattening film 28 is formed on the substrate 11 via a first insulating film 25, a second insulating film 26, and a light-shielding film 27 so as to cover the back surface S2 of the substrate 11, whereby the back surface S2 of the substrate 11 is formed.
  • the upper surface is flat.
  • the flattening film 28 is, for example, an organic film such as a resin film.
  • the color filter 29 has a function of transmitting light having a predetermined wavelength, and is formed on the flattening film 28 for each pixel 1.
  • the color filters 29 for red (R), green (G), and blue (B) are arranged above the photoelectric conversion unit 12 of the red, green, and blue pixels 1, respectively.
  • the color filter 29 for infrared light may be arranged above the photoelectric conversion unit 12 of the infrared light pixel 1. The light transmitted through each color filter 29 is incident on the photoelectric conversion unit 12 via the flattening film 28.
  • the on-chip lens 30 has a function of condensing incident light, and is formed on the color filter 29 for each pixel 1.
  • the light collected by each on-chip lens 30 is incident on the photoelectric conversion unit 12 via the color filter 29 and the flattening film 28.
  • Each on-chip lens 30 of the present embodiment is made of a material through which light is transmitted, and the on-chip lenses 37 are connected to each other via this material.
  • the insulating layer 31 is formed on the surface S1 of the substrate 11 and functions as a gate insulating film of each pixel transistor.
  • FIG. 2 shows a cross section of the gate insulating film of the transfer transistor TRY, which will be described later (see FIG. 16).
  • the insulating layer 31 is, for example, a laminated film including a first insulating film 31a, a second insulating film 31b, and a third insulating film 31c laminated in order on the surface S1 of the substrate 11.
  • the first insulating film 31a is, for example, a silicon oxide film (SiO 2 film).
  • the second insulating film 31b is, for example, a silicon nitride film (SiN film).
  • the third insulating film 31c is, for example, a silicon oxide film (SiO 2 film).
  • the interlayer insulating film 32 is formed on the surface S1 of the substrate 11 so as to cover the insulating layer 31, the electrode layer 33, and the light-shielding film 34.
  • the interlayer insulating film 32 is, for example, a laminated film including a silicon oxide film (SiO 2 film) and another insulating film.
  • the electrode layer 33 is formed on the surface S1 of the substrate 11 via the insulating layer 31, and functions as a gate electrode of each pixel transistor.
  • FIG. 2 shows a cross section of the gate electrode of the transfer transistor TRY, which will be described later (see FIG. 16).
  • the electrode layer 33 is, for example, a polysilicon layer or a metal layer.
  • the light-shielding film 34 is formed on the surface S1 of the substrate 11 via the insulating layer 31 and the electrode layer 33, and is in contact with the electrode layer 33. Further, since the light-shielding film 23 penetrates the insulating layer 31 as described above, the light-shielding film 34 is in contact with the light-shielding film 23 on the lower surface of the light-shielding film 23. As a result, the light-shielding film 34 of the present embodiment is electrically connected to the light-shielding film 27 via the light-shielding film 23.
  • the light-shielding film 34 is a film containing a metal element such as tungsten (W), aluminum (Al), or copper (Cu), and has an effect of blocking light.
  • the light-shielding film 34 is formed in a different process from the light-shielding film 23 as described later in the present embodiment, the light-shielding film 34 may be formed in the same process as the light-shielding film 23.
  • the light-shielding film 23 and the light-shielding film 34 in this case are also examples of the first and second light-shielding films of the present disclosure, respectively.
  • the light-shielding film 27 outside the substrate 11 is formed in the same process as the light-shielding film 27 inside the substrate 11 in the present embodiment, but may be formed in a different process from the light-shielding film 27 inside the substrate 11.
  • the light-shielding film 27 inside the substrate 11 and the light-shielding film 27 outside the substrate 11 in this case are also examples of the third light-shielding film of the present disclosure.
  • the wiring layers 36 to 39 are sequentially provided on the surface S1 of the substrate 11 to form a multi-layer wiring structure.
  • the wiring layers 36 to 39 are provided in the interlayer insulating film 32, and are arranged below the insulating layer 31, the electrode layer 33, and the light-shielding film 34.
  • the contact plug 35 electrically connects between the wiring layer 36 and the electrode layer 33, and between the wiring layer 36 and the light-shielding film 34.
  • the via plug 40 electrically connects between the wiring layers 36 to 39.
  • the multilayer wiring structure of the present embodiment includes four wiring layers 36 to 39, but may include three or less or five or more wiring layers. Each of the wiring layers 36 to 39 contains various wirings, and each pixel transistor is driven by using these wirings.
  • the support substrate 41 is provided on the surface S1 of the substrate 11 via an interlayer insulating film 32 or the like, and is provided to ensure the strength of the substrate 11.
  • the support substrate 41 is, for example, a semiconductor substrate such as a silicon (Si) substrate.
  • the layer 42 includes an insulating layer 31, an interlayer insulating film 32, an electrode layer 33, a light-shielding film 34, a contact plug 35, wiring layers 36 to 39, and a via plug 40.
  • the layer 42 of the present embodiment is a multi-layer wiring layer including a multi-layer wiring structure formed by the wiring layers 36 to 39.
  • the light incident on the on-chip lens 30 is collected by the on-chip lens 30, passes through the color filter 29, and is incident on the photoelectric conversion unit 12.
  • the photoelectric conversion unit 12 converts this light into an electric charge by photoelectric conversion to generate a signal charge.
  • the signal charge is output as a pixel signal via the vertical signal line 8 in the wiring layers 36 to 39.
  • FIG. 4 is a cross-sectional view showing the structure of the solid-state image sensor of the comparative example.
  • FIG. 4 shows a vertical cross section of the pixel array region 2 of FIG. 1, specifically, shows a vertical cross section of three pixels 1 in the pixel array region 2.
  • FIG. 5 is also referred to as appropriate.
  • FIG. 5 is an enlarged cross-sectional view showing the structure of the solid-state image sensor of this comparative example.
  • the groove 21 of this comparative example is formed in the substrate 11 from the back surface S2 side of the substrate 11 and is filled with the first insulating film 25, the second insulating film 26, and the light-shielding film 27. There is. Further, the groove 21 of this comparative example penetrates the substrate 11, but does not penetrate the insulating layer 31. Specifically, as shown in FIG. 5, the groove 21 of this comparative example reaches the second insulating film 31b but does not reach the third insulating film 31c, and as a result, the light-shielding film 34 Not in contact with.
  • the solid-state image sensor of the first embodiment is compared with the solid-state image sensor of this comparative example.
  • the solid-state image sensor is used between the portion where the SiN break occurs and the portion where the SiN break does not occur. Variations in white characteristics will occur.
  • the insulating film covering the side surface of the groove 21 of this comparative example is the first insulating film 25 and the second insulating film 26 formed by ALD, it is difficult to thin the insulating film covering the side surface of the groove 21. It becomes a problem. As a result, it becomes necessary to increase the size of the groove 21 and reduce the size of the photoelectric conversion unit 12, and the amount of saturation signal decreases.
  • the groove 21 of this comparative example penetrates the insulating layer 31, the following problems occur.
  • the groove 21 is formed in the substrate 11 from the back surface S2 side of the substrate 11.
  • the groove 21 penetrates the insulating layer 31 and reaches the light-shielding film 34, the light-shielding film 34 is exposed to the chemical solution when the inside of the groove 21 is treated with a chemical solution such as a thermal phosphoric acid aqueous solution. ..
  • a chemical solution such as a thermal phosphoric acid aqueous solution. ..
  • the groove 21 of this comparative example is formed so as not to penetrate the insulating layer 31.
  • the groove 21 of the present embodiment penetrates the substrate 11 and the insulating layer 31, as shown in FIGS. 2 and 3, the light-shielding film 23 in the groove 21 and the surface S1 of the substrate 11 are shielded from light. There is no gap between the film 34 and the film 34 where the light-shielding film does not exist. Therefore, it is possible to suppress the phenomenon that light enters the memory unit 16 through the gap. Further, since each groove 21 is formed so as to penetrate the second insulating film 31b, it is possible to suppress variations in white characteristics due to SiN break.
  • the insulating film covering the side surface of the groove 21 of the present embodiment is the insulating film 22 formed by oxidation, the insulating film covering the side surface of the groove 21 can be easily thinned. Further, since the first insulating film 25 and the second insulating film 26 of the present embodiment do not need to be formed in the groove 21, the first insulating film 25 and the second insulating film 26 do not consider the size of the groove 21. It is possible to adjust the film thickness of.
  • the groove 21 is formed in the substrate 11 from the surface S1 side of the substrate 11 before the light-shielding film 34 is formed on the surface S1 of the substrate 11. Therefore, when the inside of the groove 21 is treated with a chemical solution such as a hot phosphoric acid aqueous solution, the light-shielding film 34 does not yet exist, so that the light-shielding film 34 is not exposed to the chemical solution. This makes it possible to avoid the problem that the light-shielding film 34 is damaged by the chemical solution.
  • a chemical solution such as a hot phosphoric acid aqueous solution
  • the present embodiment it is possible to suppress the formation of a gap between the light-shielding film 23 and the light-shielding film 34, and it is possible to form a suitable light-shielding film.
  • 6 to 11 are cross-sectional views showing a method of manufacturing the solid-state image sensor of the first embodiment.
  • each groove 21 is formed in the substrate 11 from the surface S1 side of the substrate 11, and is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other.
  • the groove 21 of the present embodiment is formed so as not to penetrate the substrate 11 in the step B of FIG.
  • the insulating film 51 is formed on the entire surface of the substrate 11 (A in FIG. 7). As a result, the insulating film 51 is formed in the surface S1 of the substrate 11 and in the groove 21 of the substrate 11.
  • the insulating film 51 is, for example, a silicon nitride film (SiN film).
  • the insulating film 51 of the present embodiment is formed to recover the crystal defect damage of the substrate 11.
  • the insulating film 51 is removed from the substrate 11 using a chemical solution such as a hot phosphoric acid aqueous solution, and then the insulating layer 31 is formed on the surface S1 of the substrate 11 (B in FIG. 7).
  • the insulating layer 31 is formed by forming the first insulating film 31a, the second insulating film 31b, and the third insulating film 31c in this order on the surface S1 of the substrate 11 (see FIG. 3).
  • the insulating layer 31 of the present embodiment is not formed in the groove 21, and a structure in which the groove 21 exists in the substrate 11 and the insulating layer 31 is realized.
  • the insulating film 22 and the light-shielding film 23 are sequentially formed in each groove 21 (A in FIG. 8). Specifically, an insulating film 22 is formed on the side surface and the bottom surface of each groove 21, and the light-shielding film 23 is embedded in each groove 21 via the insulating film 22.
  • the insulating film 22 is formed, for example, by oxidizing the side surface and the bottom surface of each groove 21. In this way, the light-shielding film 23 is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other.
  • the electrode layer 33 is formed on the surface S1 of the substrate 11 via the insulating layer 31, and the light-shielding film 34 is formed on the surface S1 of the substrate 11 via the insulating layer 31 and the electrode layer 33 (B in FIG. 8). .. In this way, the transfer transistor TRY and other pixel transistors are formed on the surface S1 of the substrate 11 (see FIG. 16).
  • the light-shielding film 34 of the present embodiment is formed so as to be in contact with the electrode layer 33 and the light-shielding film 23.
  • the light-shielding film 23 is formed by the step shown in FIG. 8A
  • the light-shielding film 34 is formed by the step shown in FIG. 8B. Instead, both the light-shielding films 23 and 34 are formed. It may be formed after the electrode layer 33 is formed in the step shown in FIG. 8B.
  • the interlayer insulating film 32, the contact plug 35, the wiring layers 36 to 39, and the via plug 40 are formed on the surface S1 of the substrate 11 (A in FIG. 9).
  • the step shown in FIG. 9A is formed, for example, by alternately forming the interlayer insulating film 32 and the wiring layers 36 to 39 on the surface S1 of the substrate 11.
  • the substrate 11 is turned upside down (B in FIG. 9). As a result, the front surface S1 of the substrate 11 faces downward, and the back surface S2 of the substrate 11 faces upward.
  • the above-mentioned support substrate 41 may be adhered to the surface S1 of the substrate 11 via an interlayer insulating film 32 or the like immediately before the step shown in FIG. 9B is performed.
  • the substrate 11 is thinned from the back surface S2 (A in FIG. 10).
  • the back surface S2 of the substrate 11 is lowered to the groove 21, the insulating film 22 is removed from the bottom surface of the groove 21, and the light-shielding film 23 is exposed on the back surface S2 of the substrate 11.
  • the groove 21 and the light-shielding film 23 are processed into a shape that penetrates the substrate 11 and the insulating layer 31.
  • a plurality of grooves 24 are formed in the substrate 11 (B in FIG. 10).
  • B in FIG. 10 shows one of these plurality of grooves 24.
  • Each groove 24 is formed in the substrate 11 from the back surface S2 side of the substrate 11, and is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other.
  • the groove 24 of the present embodiment is formed so as not to penetrate the substrate 11.
  • the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are sequentially formed in the back surface S2 of the substrate 11 and in each groove 24 of the substrate 11 (A in FIG. 11). Specifically, the first insulating film 25 and the second insulating film 26 are sequentially formed on the side surface and the bottom surface of each groove 24, and a light-shielding film is formed in each groove 24 via the first insulating film 25 and the second insulating film 26. 27 is embedded. At the same time, the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are sequentially laminated on the back surface S2 of the substrate 11 outside the groove 24. In this way, the light-shielding film 27 is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other.
  • the first insulating film 25 and the second insulating film 26 are formed by, for example, ALD.
  • an opening penetrating the first insulating film 25 and the second insulating film 26 is formed on the light-shielding film 23 by etching, and the light-shielding film 23 is exposed in the opening, and then the second insulating film 23 is exposed.
  • a light-shielding film 27 is formed on the insulating film 26.
  • the light-shielding film 27 is formed so as to be in contact with the light-shielding film 23 within this opening.
  • the light-shielding film 27 inside the substrate 11 and the light-shielding film 27 outside the substrate 11 are formed in the same step, but instead, the step of forming the light-shielding film 27 inside the substrate 11 is executed. Therefore, the step of forming the light-shielding film 27 outside the substrate 11 may be executed thereafter.
  • a flattening film 28 is formed on the substrate 11 via the first insulating film 25, the second insulating film 26, and the light-shielding film 27 so as to cover the back surface S2 of the substrate 11 (B in FIG. 10). As a result, a flat surface is formed on the back surface S2 of the substrate 11.
  • the color filter 29 and the on-chip lens 30 shown in FIG. 2 are sequentially formed on the flattening film 28. In this way, the solid-state image sensor of the present embodiment is manufactured.
  • 12 to 15 are cross-sectional views showing a method of manufacturing a solid-state image sensor according to a modified example of the first embodiment. 12 to 15 will be described focusing on the differences from FIGS. 6 to 10, and the description of common points with FIGS. 6 to 10 will be omitted as appropriate.
  • the substrate 11 (A in FIG. 12).
  • the p + type semiconductor region 13, the n-type semiconductor region 14, and the p-type semiconductor region 15 of each photoelectric conversion unit 12, and the p + type semiconductor region 17, n-type semiconductor of each memory unit 16 A region 18, a p-type semiconductor region 19, another semiconductor region 20, and a first portion 21a of each groove 21 are formed (B in FIG. 12).
  • the first portion 21a of each groove 21 is formed in the substrate 11 from the surface S1 side of the substrate 11 and is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other.
  • the first portion 21a of each groove 21 shown in FIG. 12B is formed so as not to penetrate the substrate 11 like each groove 21 shown in FIG. 6B, but from each groove 21 shown in FIG. 6B. Is also shallowly formed.
  • the first portion 21a is formed, for example, from the surface S1 side of the substrate 11 into the substrate 11 by dry etching. Therefore, the width of the first portion 21a in the X direction becomes narrower from the front surface S1 side to the back surface S2 side of the substrate 11.
  • the steps shown in FIGS. 7A and 7B are executed to form the insulating layer 31 on the surface S1 of the substrate 11, and then the insulating film 22 and the light-shielding film 23 are formed in the first portion 21a of each groove 21. It is formed in order (A in FIG. 13). Further, the electrode layer 33 is formed on the surface S1 of the substrate 11 via the insulating layer 31, and the light-shielding film 34 is formed on the surface S1 of the substrate 11 via the insulating layer 31 and the electrode layer 33 (A in FIG. 13). The light-shielding film 34 of this modification is formed so as to be in contact with the electrode layer 33 and the light-shielding film 23, similarly to the light-shielding film 34 of the first embodiment.
  • the light-shielding film 34 of this modification is formed in the first portion 21a of each groove 21, the width of the light-shielding film 34 in the X direction becomes narrower from the front surface S1 side to the back surface S2 side of the substrate 11. It has become.
  • the light-shielding films 23 and 34 of this modification are examples of the first and second light-shielding films of the present disclosure, respectively.
  • the substrate 11 is thinned from the back surface S2 (A in FIG. 14). As a result, the back surface S2 of the substrate 11 is lowered to some extent, but the first portion 21a of the groove 21 is not lowered.
  • a plurality of grooves 24 and a second portion 21b of each groove 21 are formed in the substrate 11 (B in FIG. 14). B in FIG. 14 shows one of these plurality of grooves 24.
  • Each groove 24 is formed in the substrate 11 from the back surface S2 side of the substrate 11, and is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other.
  • the groove 24 of this modification is formed so as not to penetrate the substrate 11 like the groove 24 of the first embodiment.
  • the groove 24 is formed, for example, from the back surface S2 side of the substrate 11 into the substrate 11 by dry etching. Therefore, the width of the groove 24 in the X direction becomes wider from the front surface S1 side to the back surface S2 side of the substrate 11.
  • each groove 21 is formed in the substrate 11 from the back surface S2 side of the substrate 11, and is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other.
  • the second portion 21b of each groove 21 of this modification is formed so as to reach the corresponding first portion 21a.
  • each groove 21 includes the first portion 21a and the second portion 21b, and is processed into a shape that penetrates the inside of the substrate 11 and the inside of the insulating layer 31.
  • the second portion 21b is formed, for example, from the back surface S2 side of the substrate 11 into the substrate 11 by dry etching. Therefore, the width of the second portion 21b in the X direction becomes wider from the front surface S1 side to the back surface S2 side of the substrate 11.
  • the groove 21 of this modification is formed at substantially the same position as the groove 21 of the first embodiment, but the shape of the side surface of each groove 21 of this modification is different from the side surface of each groove 21 of the first embodiment. It has a different shape.
  • the groove 24 and the second portion 21b of the groove 21 may be formed at the same time or in order, but it is desirable that the grooves 24 and the second portion 21b are formed at the same time.
  • the depth of the first portion 21a of the groove 21 may be set so that the depth of the groove 24 and the depth of the second portion 21b are the same. desirable.
  • the insulating film 22 may or may not be removed from the bottom surface of the first portion 21a of each groove 21.
  • the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are placed in the back surface S2 of the substrate 11, in each groove 24 of the substrate 11, and in the second portion 21b of each groove 21 of the substrate 11. It is formed in order (A in FIG. 15). Specifically, the first insulating film 25 and the second insulating film 26 are sequentially formed on the side surfaces and the bottom surface of each groove 24 and each second portion 21b, and the first insulation is formed in each groove 24 and each second portion 21b.
  • the light-shielding film 27 is embedded via the film 25 and the second insulating film 26.
  • the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are sequentially laminated on the back surface S2 of the substrate 11 outside the groove 24.
  • the light-shielding film 27 is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other in the groove 24 or the second portion 21b. Since the light-shielding film 27 of this modification is formed in each groove 24 and in each second portion 21b, the width of the light-shielding film 27 in the substrate 11 in the X direction is widened in each groove 24 as well in each second portion 21b. Even inside, it becomes wider as it goes from the front surface S1 side of the substrate 11 to the back surface S2 side.
  • the light-shielding film 27 of this modification is an example of the third light-shielding film of the present disclosure.
  • the light-shielding film 27 is formed on the second insulating film 26 without forming the opening penetrating the first insulating film 25 and the second insulating film 26 on the light-shielding film 23.
  • the light-shielding film 27 is formed so as not to come into contact with the light-shielding film 23.
  • an opening penetrating the first insulating film 25 and the second insulating film 26 may be formed on the light-shielding film 23, and then the light-shielding film 27 may be formed on the second insulating film 26. This opening is formed so as to penetrate the first insulating film 25 and the second insulating film 26 formed on the bottom surface of the second portion 21b.
  • this opening is formed in the groove 21.
  • the insulating film 22 is removed from the bottom surface of the first portion 21b when the second portion 21b is formed or the opening is formed, the light-shielding film 27 is formed so as to be in contact with the light-shielding film 23.
  • the flattening film 28 is formed on the substrate 11 via the first insulating film 25, the second insulating film 26, and the light-shielding film 27 (B in FIG. 15). After that, the color filter 29 and the on-chip lens 30 shown in FIG. 2 are sequentially formed on the flattening film 28. In this way, the solid-state image sensor of this modification is manufactured.
  • FIG. 16 is a plan view showing the structure of the solid-state image sensor of the first embodiment.
  • FIG. 16 schematically shows the planar structure of the four pixels 1 in the pixel array 2 of FIG.
  • the photoelectric conversion unit 12 and the memory unit 16 in each pixel 1 are adjacent to each other in the X direction.
  • the groove 21 and the groove 24 of the present embodiment are provided between the photoelectric conversion unit 12 and the memory unit 16 in the same pixel 1 and between the photoelectric conversion unit 12 and the memory unit 16 in different pixels 1. .. This is the same as the groove 21 and the groove 24 shown in FIG. FIG. 2 shows an XZ cross section along the AA'line shown in FIG.
  • FIG. 16 shows the transfer transistors TRG, TRX, and TRG of each pixel 1, the transfer transistor (emission transistor) OFG shared between the pixels 1, the reset transistor RST, the amplification transistor AMP, the selection transistor SEL, and the dummy transistor (Dummy). ) And. These pixel transistors are provided on the surface S1 of the substrate 11.
  • FIG. 16 further shows a floating diffusion unit FD shared between pixels 1 and another diffusion unit OFD. These diffusion portions are provided in the semiconductor region 20 in the substrate 11.
  • the grooves 21 and the grooves 24 of the present embodiment are arranged on a plurality of straight lines extending in the Y direction, and the grooves 21 and the grooves 24 are alternately arranged on each straight line. Therefore, on each straight line, the groove 21 and the groove 24 are connected to each other in the substrate 11. Details of such grooves 21 and 24 will be described with reference to FIG.
  • the arrangement of the grooves 21 and 24 shown in FIG. 16 may be the solid-state image sensor of the first embodiment shown in FIGS. 6 to 11 or the solid-state image sensor of the modified example of the first embodiment shown in FIGS. 12 to 15. It is common.
  • FIG. 17 is a cross-sectional view showing the structure of the solid-state image sensor of the first embodiment (A in FIG. 17) and the structure of the solid-state image sensor of the modified example of the first embodiment (B in FIG. 17). 17A and B show a YZ cross section along the BB'line shown in FIG.
  • the groove 21 penetrates the substrate 11 and the insulating layer 31, and the insulating film 22 and the light-shielding film 23 are formed in each groove 21. Further, in A of FIG. 17, the groove 24 does not penetrate the substrate 11, and the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are formed in each groove 24.
  • the groove 21 and the groove 24 shown in A of FIG. 17 are connected to each other in the substrate 11.
  • the insulating film 22, the first insulating film 25, and the second insulating film 26 are interposed between the light-shielding film 23 in the groove 21 and the light-shielding film 27 in the groove 24.
  • the light-shielding film 23 of the present embodiment is in contact with the light-shielding film 27 outside the groove 24, not with the light-shielding film 27 inside the groove 24 (see FIG. 2).
  • the groove 21 penetrates the substrate 11 and the insulating layer 31, but not only the region including the insulating film 22 and the light-shielding film 23, but also the first insulating film 25, the second insulating film 26, and the insulating film 26. It also includes a region including the light-shielding film 27.
  • the former region is the first portion 21a and the latter region is the second portion 21b.
  • B shows the latter region (second portion 21b) with a broken line.
  • the groove 24 does not penetrate the substrate 11, and the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are formed in each groove 24.
  • the groove 21 and the groove 24 shown in FIG. 17B are connected to each other at the points indicated by the broken lines in the substrate 11.
  • the insulating film 22, the first insulating film 25, and the first insulating film 25 are between the light-shielding film 23 in the first portion 21a of the groove 21 and the light-shielding film 27 in the second portion 21b of the groove 21 and in the groove 24.
  • 2 Insulating film 26 is interposed.
  • the insulating film 22, the first insulating film 25, and the second insulating film 26 are not interposed between the light-shielding film 27 in the second portion 21b of the groove 21 and the light-shielding film 27 in the groove 24. ..
  • the structure shown in A of FIG. 17 has an advantage that the groove 21 does not need to be formed separately from the first portion 21a and the second portion 21b, and the groove 21 can be easily formed.
  • it is generally required to align the position of the groove 21 in the Y direction with the position of the groove 24 in the Y direction with high accuracy.
  • the structure shown in FIG. 17B has an advantage that such alignment is not required.
  • the light-shielding film 21 in the substrate 11 and the light-shielding film 34 on the surface S1 of the substrate 11 are formed so as to be in contact with each other. Therefore, according to the present embodiment and its modifications, it is possible to form a suitable light-shielding film, such as suppressing the formation of a gap between the light-shielding film 23 and the light-shielding film 34. ..
  • FIG. 18 is a block diagram showing a configuration example of an electronic device.
  • the electrical device shown in FIG. 18 is a camera 100.
  • the camera 100 includes an optical unit 101 including a lens group and the like, an image pickup device 102 which is a solid-state image pickup device of the first embodiment, a DSP (Digital Signal Processor) circuit 103 which is a camera signal processing circuit, a frame memory 104, and the like. It includes a display unit 105, a recording unit 106, an operation unit 107, and a power supply unit 108. Further, the DSP circuit 103, the frame memory 104, the display unit 105, the recording unit 106, the operation unit 107, and the power supply unit 108 are connected to each other via the bus line 109.
  • DSP Digital Signal Processor
  • the optical unit 101 takes in incident light (image light) from the subject and forms an image on the image pickup surface of the image pickup device 102.
  • the image pickup apparatus 102 converts the amount of incident light imaged on the image pickup surface by the optical unit 101 into an electric signal in pixel units, and outputs the light amount as a pixel signal.
  • the DSP circuit 103 performs signal processing on the pixel signal output by the image pickup device 102.
  • the frame memory 104 is a memory for storing one screen of a moving image or a still image captured by the image pickup apparatus 102.
  • the display unit 105 includes a panel-type display device such as a liquid crystal panel or an organic EL panel, and displays a moving image or a still image captured by the image pickup device 102.
  • the recording unit 106 records a moving image or a still image captured by the image pickup apparatus 102 on a recording medium such as a hard disk or a semiconductor memory.
  • the operation unit 107 issues operation commands for various functions of the camera 100 under the operation of the user.
  • the power supply unit 108 appropriately supplies various power sources that serve as operating power sources for the DSP circuit 103, the frame memory 104, the display unit 105, the recording unit 106, and the operation unit 107 to these supply targets.
  • the solid-state image sensor can be applied to various other products.
  • the solid-state imaging device may be mounted on various moving objects such as automobiles, electric vehicles, hybrid electric vehicles, motorcycles, bicycles, personal mobility, airplanes, drones, ships, and robots.
  • FIG. 19 is a block diagram showing a configuration example of a mobile control system.
  • the mobile control system shown in FIG. 19 is a vehicle control system 200.
  • the vehicle control system 200 includes a plurality of electronic control units connected via the communication network 201.
  • the vehicle control system 200 includes a drive system control unit 210, a body system control unit 220, an outside information detection unit 230, an in-vehicle information detection unit 240, and an integrated control unit 250.
  • FIG. 19 further shows a microcomputer 251, an audio image output unit 252, and an in-vehicle network I / F (Interface) 253 as components of the integrated control unit 250.
  • the drive system control unit 210 controls the operation of the device related to the drive system of the vehicle according to various programs.
  • the drive system control unit 210 includes a driving force generator for generating a driving force of a vehicle such as an internal combustion engine and a driving motor, a driving force transmission mechanism for transmitting the driving force to wheels, and a steering wheel of the vehicle. It functions as a control device such as a steering mechanism that adjusts the angle and a braking device that generates braking force for the vehicle.
  • the body system control unit 220 controls the operation of various devices mounted on the vehicle body according to various programs.
  • the body system control unit 220 functions as a control device such as a smart key system, a keyless entry system, a power window device, and various lamps (for example, a headlamp, a back lamp, a brake lamp, a winker, and a fog lamp).
  • a radio wave transmitted from a portable device that substitutes for a key or a signal of various switches may be input to the body system control unit 220.
  • the body system control unit 220 receives such radio wave or signal input and controls a vehicle door lock device, a power window device, a lamp, and the like.
  • the outside information detection unit 230 detects information outside the vehicle equipped with the vehicle control system 200.
  • an image pickup unit 231 is connected to the vehicle outside information detection unit 230.
  • the vehicle outside information detection unit 230 causes the image pickup unit 231 to capture an image of the outside of the vehicle, and receives the captured image from the image pickup unit 231.
  • the vehicle outside information detection unit 230 may perform object detection processing or distance detection processing such as a person, a vehicle, an obstacle, a sign, or a character on a road surface based on the received image.
  • the image pickup unit 231 is an optical sensor that receives light and outputs an electric signal according to the amount of the light received.
  • the image pickup unit 231 can output an electric signal as an image or can output it as distance measurement information.
  • the light received by the image pickup unit 231 may be visible light or invisible light such as infrared light.
  • the image pickup unit 231 includes the solid-state image pickup device of the first embodiment.
  • the in-vehicle information detection unit 240 detects information inside the vehicle equipped with the vehicle control system 200.
  • a driver state detection unit 241 that detects the state of the driver is connected to the in-vehicle information detection unit 240.
  • the driver state detection unit 241 includes a camera that images the driver, and the in-vehicle information detection unit 240 has a degree of fatigue or concentration of the driver based on the detection information input from the driver state detection unit 241. May be calculated, or it may be determined whether or not the driver has fallen asleep.
  • This camera may include the solid-state image sensor of the first embodiment, and may be, for example, the camera 100 shown in FIG.
  • the microcomputer 251 calculates a control target value of the driving force generator, the steering mechanism, or the braking device based on the information inside and outside the vehicle acquired by the information detection unit 230 outside the vehicle or the information inside the vehicle 240, and controls the drive system.
  • a control command can be output to the unit 210.
  • the microcomputer 251 is a coordinated control for the purpose of realizing ADAS (Advanced Driver Assistance System) functions such as vehicle collision avoidance, impact mitigation, follow-up driving based on inter-vehicle distance, vehicle speed maintenance driving, collision warning, and lane deviation warning. It can be performed.
  • ADAS Advanced Driver Assistance System
  • the microcomputer 251 controls the driving force generator, the steering mechanism, or the braking device based on the information around the vehicle acquired by the vehicle exterior information detection unit 230 or the vehicle interior information detection unit 240, thereby controlling the driver. It is possible to perform coordinated control for the purpose of automatic driving that runs autonomously without depending on the operation.
  • the microcomputer 251 can output a control command to the body system control unit 220 based on the information outside the vehicle acquired by the vehicle outside information detection unit 230.
  • the microcomputer 251 controls the headlamps according to the position of the preceding vehicle or the oncoming vehicle detected by the outside information detection unit 230, and performs cooperative control for the purpose of anti-glare such as switching the high beam to the low beam. It can be carried out.
  • the audio image output unit 252 transmits an output signal of at least one of audio and image to an output device capable of visually or audibly notifying the passenger of the vehicle or the outside of the vehicle.
  • an audio speaker 261, a display unit 262, and an instrument panel 263 are shown as such an output device.
  • the display unit 262 may include, for example, an onboard display or a head-up display.
  • FIG. 20 is a plan view showing a specific example of the set position of the image pickup unit 231 of FIG.
  • the vehicle 300 shown in FIG. 20 includes image pickup units 301, 302, 303, 304, and 305 as image pickup units 231.
  • the image pickup units 301, 302, 303, 304, and 305 are provided, for example, at positions such as the front nose, side mirrors, rear bumpers, back doors, and the upper part of the windshield in the vehicle interior of the vehicle 300.
  • the image pickup unit 301 provided in the front nose mainly acquires an image in front of the vehicle 300.
  • the image pickup unit 302 provided in the left side mirror and the image pickup section 303 provided in the right side mirror mainly acquire an image of the side of the vehicle 300.
  • the image pickup unit 304 provided on the rear bumper or the back door mainly acquires an image of the rear of the vehicle 300.
  • the image pickup unit 305 provided on the upper part of the windshield in the vehicle interior mainly acquires an image in front of the vehicle 300.
  • the image pickup unit 305 is used, for example, to detect a preceding vehicle, a pedestrian, an obstacle, a traffic light, a traffic sign, a lane, or the like.
  • FIG. 20 shows an example of the imaging range of the imaging units 301, 302, 303, 304 (hereinafter referred to as “imaging unit 301 to 304”).
  • the imaging range 311 indicates the imaging range of the imaging unit 301 provided on the front nose.
  • the image pickup range 312 indicates the image pickup range of the image pickup unit 302 provided on the left side mirror.
  • the image pickup range 313 indicates the image pickup range of the image pickup unit 303 provided on the right side mirror.
  • the image pickup range 314 indicates the image pickup range of the image pickup unit 304 provided on the rear bumper or the back door.
  • the imaging range 311, 312, 313, 314 will be referred to as "imaging range 311 to 314".
  • At least one of the image pickup units 301 to 304 may have a function of acquiring distance information.
  • at least one of the image pickup units 301 to 304 may be a stereo camera including a plurality of image pickup devices, or may be an image pickup device having pixels for phase difference detection.
  • the microcomputer 251 (FIG. 19) is based on the distance information obtained from the imaging units 301 to 304, the distance to each three-dimensional object within the imaging range 311 to 314, and the temporal change of this distance (vehicle 300). Relative velocity to) is calculated. Based on these calculation results, the microcomputer 251 is the closest three-dimensional object on the traveling path of the vehicle 300, and is a three-dimensional object traveling at a predetermined speed (for example, 0 km / h or more) in almost the same direction as the vehicle 300. , Can be extracted as a preceding vehicle.
  • a predetermined speed for example, 0 km / h or more
  • the microcomputer 251 can set an inter-vehicle distance to be secured in front of the preceding vehicle in advance, and can perform automatic brake control (including follow-up stop control), automatic acceleration control (including follow-up start control), and the like. As described above, according to this example, it is possible to perform coordinated control for the purpose of automatic driving or the like that autonomously travels without the operation of the driver.
  • the microcomputer 251 classifies three-dimensional object data related to a three-dimensional object into two-wheeled vehicles, ordinary vehicles, large vehicles, pedestrians, electric poles, and other three-dimensional objects based on the distance information obtained from the imaging units 301 to 304. It can be extracted and used for automatic avoidance of obstacles. For example, the microcomputer 251 distinguishes obstacles around the vehicle 300 into obstacles that can be seen by the driver of the vehicle 300 and obstacles that are difficult to see. Then, the microcomputer 251 determines the collision risk indicating the risk of collision with each obstacle, and when the collision risk is equal to or higher than the set value and there is a possibility of collision, the microcomputer 251 is used via the audio speaker 261 or the display unit 262. By outputting an alarm to the driver and performing forced deceleration and avoidance steering via the drive system control unit 210, driving support for collision avoidance can be provided.
  • At least one of the image pickup units 301 to 304 may be an infrared camera that detects infrared rays.
  • the microcomputer 251 can recognize a pedestrian by determining whether or not a pedestrian is present in the captured images of the imaging units 301 to 304. Such recognition of a pedestrian is, for example, whether or not the pedestrian is a pedestrian by performing a procedure for extracting feature points in the captured images of the image pickup units 301 to 304 as an infrared camera and a pattern matching process on a series of feature points showing the outline of the object. It is performed by the procedure for determining.
  • the audio image output unit 252 When the microcomputer 251 determines that a pedestrian is present in the captured images of the imaging units 301 to 304 and recognizes the pedestrian, the audio image output unit 252 has a square contour line for emphasizing the recognized pedestrian.
  • the display unit 262 is controlled so as to superimpose and display. Further, the audio image output unit 252 may control the display unit 262 so as to display an icon or the like indicating a pedestrian at a desired position.
  • FIG. 21 is a diagram showing an example of a schematic configuration of an endoscopic surgery system to which the technique according to the present disclosure (the present technique) can be applied.
  • FIG. 21 illustrates how the surgeon (doctor) 531 is performing surgery on patient 532 on patient bed 533 using the endoscopic surgery system 400.
  • the endoscopic surgery system 400 includes an endoscope 500, other surgical tools 510 such as an abdominal tube 511 and an energy treatment tool 512, and a support arm device 520 that supports the endoscope 500.
  • a cart 600 equipped with various devices for endoscopic surgery.
  • the endoscope 500 is composed of a lens barrel 501 in which a region having a predetermined length from the tip is inserted into the body cavity of the patient 532, and a camera head 502 connected to the base end of the lens barrel 501.
  • the endoscope 500 configured as a so-called rigid mirror having a rigid lens barrel 501 is shown, but the endoscope 500 may be configured as a so-called flexible mirror having a flexible lens barrel. good.
  • An opening in which an objective lens is fitted is provided at the tip of the lens barrel 501.
  • a light source device 603 is connected to the endoscope 500, and the light generated by the light source device 603 is guided to the tip of the lens barrel by a light guide extending inside the lens barrel 501, and is an objective. It is irradiated toward the observation target in the body cavity of the patient 532 through the lens.
  • the endoscope 500 may be a direct endoscope, a perspective mirror, or a side endoscope.
  • An optical system and an image sensor are provided inside the camera head 502, and the reflected light (observation light) from the observation target is focused on the image sensor by the optical system.
  • the observation light is photoelectrically converted by the image pickup device, and an electric signal corresponding to the observation light, that is, an image signal corresponding to the observation image is generated.
  • the image signal is transmitted as RAW data to the camera control unit (CCU: Camera Control Unit) 601.
  • the CCU 601 is composed of a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), and the like, and comprehensively controls the operations of the endoscope 500 and the display device 602. Further, the CCU 601 receives an image signal from the camera head 502, and performs various image processing on the image signal for displaying an image based on the image signal, such as a development process (demosaic process).
  • a development process demosaic process
  • the display device 602 displays an image based on the image signal processed by the CCU 601 under the control of the CCU 601.
  • the light source device 603 is composed of, for example, a light source such as an LED (Light Emitting Diode), and supplies irradiation light for photographing an operating part or the like to the endoscope 500.
  • a light source such as an LED (Light Emitting Diode)
  • LED Light Emitting Diode
  • the input device 604 is an input interface for the endoscopic surgery system 11000.
  • the user can input various information and input instructions to the endoscopic surgery system 400 via the input device 604.
  • the user inputs an instruction to change the imaging conditions (type of irradiation light, magnification, focal length, etc.) by the endoscope 500.
  • the treatment tool control device 605 controls the drive of the energy treatment tool 512 for cauterizing tissue, incising, sealing a blood vessel, or the like.
  • the pneumoperitoneum device 606 gas in the body cavity through the pneumoperitoneum tube 511 in order to inflate the body cavity of the patient 532 for the purpose of securing the field of view by the endoscope 500 and securing the work space of the operator. Is sent.
  • the recorder 607 is a device capable of recording various information related to surgery.
  • the printer 608 is a device capable of printing various information related to surgery in various formats such as text, images, and graphs.
  • the light source device 603 that supplies the irradiation light to the endoscope 500 when photographing the surgical site can be composed of, for example, an LED, a laser light source, or a white light source composed of a combination thereof.
  • a white light source is configured by a combination of RGB laser light sources, the output intensity and output timing of each color (each wavelength) can be controlled with high accuracy. Therefore, the light source device 603 adjusts the white balance of the captured image. It can be carried out.
  • the laser light from each of the RGB laser light sources is irradiated to the observation target in a time-division manner, and the drive of the image sensor of the camera head 502 is controlled in synchronization with the irradiation timing to correspond to each of RGB. It is also possible to capture the image in a time-division manner. According to this method, a color image can be obtained without providing a color filter in the image pickup device.
  • the drive of the light source device 603 may be controlled so as to change the intensity of the output light at predetermined time intervals.
  • the drive of the image sensor of the camera head 502 in synchronization with the timing of the change of the light intensity to acquire an image in time division and synthesizing the image, so-called high dynamic without blackout and overexposure. Range images can be generated.
  • the light source device 603 may be configured to be able to supply light in a predetermined wavelength band corresponding to special light observation.
  • special light observation for example, by utilizing the wavelength dependence of light absorption in body tissue, the surface layer of the mucous membrane is irradiated with light in a narrower band than the irradiation light (that is, white light) during normal observation.
  • a so-called narrow band imaging is performed in which a predetermined tissue such as a blood vessel is photographed with high contrast.
  • fluorescence observation may be performed in which an image is obtained by fluorescence generated by irradiating with excitation light.
  • the body tissue is irradiated with excitation light to observe the fluorescence from the body tissue (autofluorescence observation), or a reagent such as indocyanine green (ICG) is locally injected into the body tissue and the body tissue is injected. It is possible to obtain a fluorescence image by irradiating the excitation light corresponding to the fluorescence wavelength of the reagent.
  • the light source device 603 may be configured to be capable of supplying narrowband light and / or excitation light corresponding to such special light observation.
  • FIG. 22 is a block diagram showing an example of the functional configuration of the camera head 502 and CCU601 shown in FIG. 21.
  • the camera head 502 includes a lens unit 701, an image pickup unit 702, a drive unit 703, a communication unit 704, and a camera head control unit 705.
  • the CCU 601 has a communication unit 711, an image processing unit 712, and a control unit 713.
  • the camera head 502 and the CCU 601 are communicably connected to each other by a transmission cable 700.
  • the lens unit 701 is an optical system provided at a connection portion with the lens barrel 501.
  • the observation light taken in from the tip of the lens barrel 501 is guided to the camera head 502 and incident on the lens unit 701.
  • the lens unit 701 is configured by combining a plurality of lenses including a zoom lens and a focus lens.
  • the image pickup unit 702 is composed of an image pickup element.
  • the image pickup element constituting the image pickup unit 702 may be one (so-called single plate type) or a plurality (so-called multi-plate type).
  • each image pickup element may generate an image signal corresponding to each of RGB, and a color image may be obtained by synthesizing them.
  • the image pickup unit 702 may be configured to have a pair of image pickup elements for acquiring image signals for the right eye and the left eye corresponding to 3D (Dimensional) display, respectively.
  • the 3D display enables the operator 531 to more accurately grasp the depth of the living tissue in the surgical site.
  • a plurality of lens units 701 may be provided corresponding to each image pickup element.
  • the image pickup unit 702 is, for example, the solid-state image pickup device of the first embodiment.
  • the image pickup unit 702 does not necessarily have to be provided on the camera head 502.
  • the image pickup unit 702 may be provided inside the lens barrel 501 immediately after the objective lens.
  • the drive unit 703 is composed of an actuator, and the zoom lens and the focus lens of the lens unit 701 are moved by a predetermined distance along the optical axis under the control of the camera head control unit 705. As a result, the magnification and focus of the image captured by the image pickup unit 702 can be adjusted as appropriate.
  • the communication unit 704 is configured by a communication device for transmitting and receiving various information to and from the CCU 601.
  • the communication unit 704 transmits the image signal obtained from the image pickup unit 702 as RAW data to the CCU 601 via the transmission cable 700.
  • the communication unit 704 receives a control signal for controlling the drive of the camera head 502 from the CCU 601 and supplies the control signal to the camera head control unit 705.
  • the control signal includes, for example, information to specify the frame rate of the captured image, information to specify the exposure value at the time of imaging, and / or information to specify the magnification and focus of the captured image. Contains information about the condition.
  • the image pickup conditions such as the frame rate, exposure value, magnification, and focus may be appropriately specified by the user, or may be automatically set by the control unit 713 of the CCU 601 based on the acquired image signal. good.
  • the endoscope 500 is equipped with a so-called AE (Auto Exposure) function, an AF (Auto Focus) function, and an AWB (Auto White Balance) function.
  • the camera head control unit 705 controls the drive of the camera head 502 based on the control signal from the CCU 601 received via the communication unit 704.
  • the communication unit 711 is composed of a communication device for transmitting and receiving various information to and from the camera head 502.
  • the communication unit 711 receives an image signal transmitted from the camera head 502 via the transmission cable 700.
  • the communication unit 711 transmits a control signal for controlling the drive of the camera head 502 to the camera head 502.
  • Image signals and control signals can be transmitted by telecommunications, optical communication, or the like.
  • the image processing unit 712 performs various image processing on the image signal which is the RAW data transmitted from the camera head 502.
  • the control unit 713 performs various controls related to the imaging of the surgical site and the like by the endoscope 500 and the display of the captured image obtained by the imaging of the surgical site and the like. For example, the control unit 713 generates a control signal for controlling the drive of the camera head 502.
  • control unit 713 causes the display device 602 to display an image captured by the surgical unit or the like based on the image signal processed by the image processing unit 712.
  • the control unit 713 may recognize various objects in the captured image by using various image recognition techniques.
  • the control unit 713 detects a surgical tool such as forceps, a specific biological part, bleeding, mist when using the energy treatment tool 512, etc. by detecting the shape, color, etc. of the edge of the object included in the captured image. Can be recognized.
  • the control unit 713 displays the captured image on the display device 602
  • the control unit 713 may superimpose and display various surgical support information on the image of the surgical unit by using the recognition result. By superimposing and displaying the surgery support information and presenting it to the surgeon 531 it is possible to reduce the burden on the surgeon 531 and to ensure that the surgeon 531 can proceed with the surgery.
  • the transmission cable 700 connecting the camera head 502 and the CCU 601 is an electric signal cable compatible with electric signal communication, an optical fiber compatible with optical communication, or a composite cable thereof.
  • the communication is performed by wire using the transmission cable 700, but the communication between the camera head 502 and the CCU 601 may be performed wirelessly.
  • a substrate having a first surface that is opposite to the light incident surface and a second surface that is the light incident surface.
  • a first pixel having a first photoelectric conversion unit and a first charge storage unit provided in the substrate, and A second pixel having a second photoelectric conversion unit and a second charge storage unit provided in the substrate, and A first light-shielding film provided between the second photoelectric conversion unit and the first charge storage unit adjacent to each other in the substrate.
  • a multilayer wiring layer provided on the first surface side of the substrate, and A second light-shielding film provided in the multilayer wiring layer and in contact with the first light-shielding film, and A solid-state image sensor.
  • the multilayer wiring layer includes an insulating layer provided on the first surface of the substrate.
  • a substrate having a first surface that is opposite to the light incident surface and a second surface that is the light incident surface.
  • a first pixel having a first photoelectric conversion unit and a first charge storage unit provided in the substrate, and A second pixel having a second photoelectric conversion unit and a second charge storage unit provided in the substrate, and A first groove that penetrates the substrate and is provided between the adjacent second photoelectric conversion unit and the first charge storage unit, and is provided on the first surface side in the substrate.
  • a first groove including a first portion and a second portion provided on the second surface side in the substrate.
  • the width of the first portion becomes narrower from the first surface side to the second surface side.
  • the width of the second portion becomes wider from the first surface side to the second surface side.
  • a substrate having a first surface opposite to the light incident surface and a second surface to be the light incident surface is prepared.
  • a first pixel having a first photoelectric conversion unit and a first charge storage unit is formed in the substrate.
  • a second pixel having a second photoelectric conversion unit and a second charge storage unit is formed in the substrate.
  • a first light-shielding film is formed between the adjacent second photoelectric conversion unit and the first charge storage unit.
  • a multilayer wiring layer is formed on the first surface side of the substrate, and the multilayer wiring layer is formed.
  • a second light-shielding film in contact with the first light-shielding film is formed in the multilayer wiring layer.
  • Pixel 2 Pixel array area 3: Control circuit, 4: Vertical drive circuit, 5: Column signal processing circuit, 6: Horizontal drive circuit, 7: Output circuit, 8: Vertical signal line, 9: Horizontal signal line, 11: Substrate, 12: Photoelectric conversion unit, 13: p + type semiconductor region, 14: n-type semiconductor region, 15: p-type semiconductor area, 16: memory unit, 17: p + type semiconductor area, 18: n-type semiconductor region, 19: p-type semiconductor region, 20: other semiconductor region, 21: groove, 21a: first part, 21b: second part, 22: insulating film, 23: light-shielding film, 24: groove, 25: first insulating film, 26: second insulating film, 27: light-shielding film, 28: Flattening film, 29: Color filter, 30: On-chip lens, 31: Insulation layer, 31a: First insulating film, 31b: Second insulating film, 31c: Third insulating film, 32: interlayer insulating film, 32:

Abstract

[Problem] To provide a solid-state imaging device which enables formation of a suitable light shielding film, and a method for manufacturing the solid-state imaging device. [Solution] A solid-state imaging device according to the present disclosure comprises: a substrate that has a first surface which is the reverse surface from a light incidence surface, and a second surface which is a light incidence surface; a first pixel that has a first charge storage part and a first photoelectric conversion part provided in the substrate; a second pixel that has a second charge storage part and a second photoelectric conversion part provided in the substrate; a first light shielding film that is provided in the substrate between the adjacent second photoelectric conversion part and first charge storage part; a multilayer wiring layer what is provided on the first surface side of the substrate; and a second light shielding film that is provided in the multilayer wiring layer and that is in contact with the first light shielding film.

Description

固体撮像装置およびその製造方法Solid-state image sensor and its manufacturing method
　本開示は、固体撮像装置およびその製造方法に関する。 This disclosure relates to a solid-state image sensor and a method for manufacturing the same.
　固体撮像装置が光電変換部とメモリ部とを基板内に備える場合、光電変換部とメモリ部との間に溝が設けられることが一般的である。この溝は、基板を貫通する貫通部と、基板を貫通しない非貫通部とを含む場合がある。貫通部は例えば、メモリ部内に光が入り込むことを抑制するために設けられる。非貫通部は例えば、光電変換部からメモリ部に電荷を転送する経路を確保するために設けられる。貫通部および非貫通部には、一般に遮光膜が埋め込まれる。 When the solid-state image sensor includes a photoelectric conversion unit and a memory unit in the substrate, it is common that a groove is provided between the photoelectric conversion unit and the memory unit. This groove may include a penetrating portion that penetrates the substrate and a non-penetrating portion that does not penetrate the substrate. The penetrating portion is provided, for example, in order to prevent light from entering the memory portion. The non-penetrating portion is provided, for example, to secure a path for transferring charges from the photoelectric conversion unit to the memory unit. A light-shielding film is generally embedded in the penetrating portion and the non-penetrating portion.
特開２０１５－０２３２５９号公報Japanese Unexamined Patent Publication No. 2015-0232559 特開２０１８－１６０４８５号公報Japanese Unexamined Patent Publication No. 2018-160485
　しかしながら、貫通部および非貫通部内に遮光膜を設けるだけでは、固体撮像装置内の遮光が不十分になるおそれがある。また、貫通部内には薄い絶縁膜を形成しにくいことも問題となる。 However, simply providing a light-shielding film in the penetrating portion and the non-penetrating portion may result in insufficient light-shielding in the solid-state image sensor. Another problem is that it is difficult to form a thin insulating film in the penetrating portion.
　そこで、本開示は、好適な遮光膜を形成することが可能な固体撮像装置およびその製造方法を提供する。 Therefore, the present disclosure provides a solid-state image sensor capable of forming a suitable light-shielding film and a method for manufacturing the same.
　本開示の第１の側面の固体撮像装置は、光入射面の反対面となる第１面と、前記光入射面となる第２面とを有する基板と、前記基板内に設けられた第１光電変換部と第１電荷蓄積部とを有する第１画素と、前記基板内に設けられた第２光電変換部と第２電荷蓄積部とを有する第２画素と、前記基板内にて、隣接する前記第２光電変換部と前記第１電荷蓄積部との間に設けられた第１遮光膜と、前記基板の前記第１面側に設けられた多層配線層と、前記多層配線層内に設けられ、前記第１遮光膜に接している第２遮光膜とを備える。これにより例えば、第１遮光膜と第２遮光膜との間に隙間が生じることを抑制することが可能となり、好適な遮光膜を形成することが可能となる。 The solid-state imaging device on the first side surface of the present disclosure includes a substrate having a first surface opposite to the light incident surface, a second surface serving as the light incident surface, and a first surface provided in the substrate. A first pixel having a photoelectric conversion unit and a first charge storage unit, and a second pixel having a second photoelectric conversion unit and a second charge storage unit provided in the substrate are adjacent to each other in the substrate. In the first light-shielding film provided between the second photoelectric conversion unit and the first charge storage unit, the multilayer wiring layer provided on the first surface side of the substrate, and the multilayer wiring layer. It is provided with a second light-shielding film that is provided and is in contact with the first light-shielding film. As a result, for example, it is possible to suppress the formation of a gap between the first light-shielding film and the second light-shielding film, and it is possible to form a suitable light-shielding film.
　また、この第１の側面の固体撮像装置は、前記基板の前記第２面上に設けられ、前記第１電荷蓄積部と平面視で重なっており、前記第１遮光膜に接している第３遮光膜をさらに備えていてもよい。これにより例えば、第１遮光膜と第３遮光膜との間に隙間が生じることを抑制することが可能となり、好適な遮光膜を形成することが可能となる。 Further, the solid-state image sensor on the first side surface is provided on the second surface of the substrate, overlaps the first charge storage portion in a plan view, and is in contact with the first light-shielding film. A light-shielding film may be further provided. As a result, for example, it is possible to suppress the formation of a gap between the first light-shielding film and the third light-shielding film, and it is possible to form a suitable light-shielding film.
　また、この第１の側面において、前記第１遮光膜の幅は、前記第１面側から前記第２面側に進むにつれ狭くなっていてもよい。これにより例えば、基板の第１面側から基板内に第１遮光膜を形成することが可能となる。 Further, on the first side surface, the width of the first light-shielding film may be narrowed as it progresses from the first surface side to the second surface side. This makes it possible to form a first light-shielding film in the substrate from the first surface side of the substrate, for example.
　また、この第１の側面において、前記多層配線層は、前記基板の前記第１面に設けられた絶縁層を含み、前記第１遮光膜は、前記基板内および前記絶縁層内に設けられていてもよい。これにより例えば、基板および絶縁層を貫通する第１遮光膜を形成することで、第１遮光膜と第２遮光膜との間に隙間が生じることを抑制することが可能となる。 Further, on the first side surface, the multilayer wiring layer includes an insulating layer provided on the first surface of the substrate, and the first light-shielding film is provided in the substrate and in the insulating layer. You may. Thereby, for example, by forming the first light-shielding film penetrating the substrate and the insulating layer, it is possible to suppress the formation of a gap between the first light-shielding film and the second light-shielding film.
　また、この第１の側面において、前記絶縁膜は、トランジスタのゲート絶縁膜として機能してもよい。これにより例えば、基板の第１面にトランジスタが形成される場合にも、第１遮光膜と第２遮光膜との間に隙間が生じることを抑制することが可能となる。 Further, in this first aspect, the insulating film may function as a gate insulating film of a transistor. As a result, for example, even when a transistor is formed on the first surface of the substrate, it is possible to suppress the formation of a gap between the first light-shielding film and the second light-shielding film.
　また、この第１の側面において、前記第２遮光膜は、前記第１遮光膜と、前記トランジスタの電極層とに接していてもよい。これにより例えば、第１遮光膜および電極層を覆うように第２遮光膜を形成することで、第１遮光膜と第２遮光膜との間に隙間が生じることを抑制することが可能となる。 Further, on the first side surface, the second light-shielding film may be in contact with the first light-shielding film and the electrode layer of the transistor. As a result, for example, by forming the second light-shielding film so as to cover the first light-shielding film and the electrode layer, it is possible to suppress the formation of a gap between the first light-shielding film and the second light-shielding film. ..
　また、この第１の側面において、前記第１遮光膜は、前記基板を貫通する第１溝内に設けられていてもよい。これにより例えば、第１溝内に第１遮光膜を埋め込むことで、基板内に第１遮光膜を形成することが可能となる。 Further, on the first side surface, the first light-shielding film may be provided in the first groove penetrating the substrate. This makes it possible to form the first light-shielding film in the substrate, for example, by embedding the first light-shielding film in the first groove.
　また、この第１の側面において、前記第１溝の幅は、前記第１面側から前記第２面側に進むにつれ狭くなっていてよい。これにより例えば、基板の第１面側から基板内に第１溝を形成することが可能となる。 Further, on the first side surface, the width of the first groove may be narrowed as it progresses from the first surface side to the second surface side. This makes it possible to form a first groove in the substrate from the first surface side of the substrate, for example.
　また、この第１の側面において、前記第３遮光膜は、前記基板の前記第２面上と、前記基板を貫通しない第２溝内とに設けられていてもよい。これにより例えば、光電変換部から電荷蓄積部内に光が入り込むことを、第１遮光膜と第３遮光膜により抑制することが可能となる。 Further, on the first side surface, the third light-shielding film may be provided on the second surface of the substrate and in the second groove that does not penetrate the substrate. This makes it possible, for example, to prevent light from entering the charge storage unit from the photoelectric conversion unit by the first light-shielding film and the third light-shielding film.
　また、この第１の側面において、前記第２溝の幅は、前記第１面側から前記第２面側に進むにつれ広くなっていてもよい。これにより例えば、基板の第２面側から基板内に第２溝を形成することが可能となる。 Further, on the first side surface, the width of the second groove may be widened from the first surface side to the second surface side. This makes it possible to form, for example, a second groove in the substrate from the second surface side of the substrate.
　本開示の第２の側面の固体撮像装置は、光入射面の反対面となる第１面と、前記光入射面となる第２面とを有する基板と、前記基板内に設けられた第１光電変換部と第１電荷蓄積部とを有する第１画素と、前記基板内に設けられた第２光電変換部と第２電荷蓄積部とを有する第２画素と、前記基板を貫通しており、隣接する前記第２光電変換部と前記第１電荷蓄積部との間に設けられた第１溝であって、前記基板内にて前記第１面側に設けられた第１部分と、前記基板内にて前記第２面側に設けられた第２部分とを含む第１溝と、前記第１部分内に設けられた第１遮光膜と、前記基板の前記第１面側に設けられた多層配線層と、前記多層配線層内に設けられ、前記第１遮光膜に接している第２遮光膜とを備える。これにより例えば、第１遮光膜と第２遮光膜との間に隙間が生じることを抑制することが可能となり、好適な遮光膜を形成することが可能となる。 The solid-state imaging device on the second side of the present disclosure includes a substrate having a first surface opposite to the light incident surface, a second surface serving as the light incident surface, and a first surface provided in the substrate. It penetrates the first pixel having a photoelectric conversion unit and a first charge storage unit, a second pixel having a second photoelectric conversion unit and a second charge storage unit provided in the substrate, and the substrate. A first groove provided between the adjacent second photoelectric conversion unit and the first charge storage unit, the first portion provided on the first surface side in the substrate, and the said. A first groove including a second portion provided on the second surface side in the substrate, a first light-shielding film provided in the first portion, and a first light-shielding film provided on the first surface side of the substrate. It includes a multi-layer wiring layer and a second light-shielding film provided in the multi-layer wiring layer and in contact with the first light-shielding film. As a result, for example, it is possible to suppress the formation of a gap between the first light-shielding film and the second light-shielding film, and it is possible to form a suitable light-shielding film.
　また、この第２の側面において、前記第１部分の幅は、前記第１面側から前記第２面側に進むにつれ狭くなっており、前記第２部分の幅は、前記第１面側から前記第２面側に進むにつれ広くなっていてもよい。これにより例えば、基板の第１面側および第２面側から基板内に第１溝を形成することが可能となる。 Further, on the second side surface, the width of the first portion becomes narrower from the first surface side to the second surface side, and the width of the second portion is from the first surface side. It may become wider as it goes to the second surface side. This makes it possible to form a first groove in the substrate from the first surface side and the second surface side of the substrate, for example.
　また、この第２の側面の固体撮像装置は、前記基板の前記第２面上と、前記第２部分内とに設けられ、前記第１電荷蓄積部と平面視で重なっている第３遮光膜をさらに備えていてもよい。これにより例えば、基板の第１面側から第１溝内に第１遮光膜を形成し、基板の第２面側から第１溝内に第３遮光膜を形成することが可能となる。 Further, the solid-state image sensor on the second side surface is provided on the second surface of the substrate and in the second portion, and is overlapped with the first charge storage portion in a plan view. May be further provided. This makes it possible, for example, to form a first light-shielding film in the first groove from the first surface side of the substrate and to form a third light-shielding film in the first groove from the second surface side of the substrate.
　また、この第２の側面において、前記第３遮光膜はさらに、前記基板を貫通しない第２溝内に設けられていてもよい。これにより例えば、光電変換部から電荷蓄積部内に光が入り込むことを、第１遮光膜と第３遮光膜により抑制することが可能となる。 Further, on the second side surface, the third light-shielding film may be further provided in a second groove that does not penetrate the substrate. This makes it possible, for example, to prevent light from entering the charge storage unit from the photoelectric conversion unit by the first light-shielding film and the third light-shielding film.
　また、この第２の側面において、前記第２溝の幅は、前記第１面側から前記第２面側に進むにつれ広くなっていてもよい。これにより例えば、基板の第２面側から基板内に第２溝を形成することが可能となる。 Further, on this second side surface, the width of the second groove may become wider as it progresses from the first surface side to the second surface side. This makes it possible to form, for example, a second groove in the substrate from the second surface side of the substrate.
　また、この第２の側面において、前記第１溝と前記第２溝は、前記基板内で互いにつながっていてもよい。これにより例えば、第１溝内の第１遮光膜と第２溝内の第３遮光膜との間の隙間から、電荷蓄積部内に光が入り込むことを抑制することが可能となる。 Further, on the second side surface, the first groove and the second groove may be connected to each other in the substrate. This makes it possible to suppress light from entering the charge storage portion from the gap between the first light-shielding film in the first groove and the third light-shielding film in the second groove, for example.
　本開示の第３の側面の固体撮像装置の製造方法は、光入射面の反対面となる第１面と、前記光入射面となる第２面とを有する基板を用意し、前記基板内に第１光電変換部と第１電荷蓄積部とを有する第１画素を形成し、前記基板内に第２光電変換部と第２電荷蓄積部とを有する第２画素を形成し、前記基板内にて、隣接する前記第２光電変換部と前記第１電荷蓄積部との間に第１遮光膜を形成し、前記基板の前記第１面側に多層配線層を形成し、前記多層配線層内に、前記第１遮光膜に接する第２遮光膜を形成することを含む。これにより例えば、第１遮光膜と第２遮光膜との間に隙間が生じることを抑制することが可能となり、好適な遮光膜を形成することが可能となる。 In the method for manufacturing a solid-state image pickup device having a third aspect surface of the present disclosure, a substrate having a first surface opposite to the light incident surface and a second surface to be the light incident surface is prepared, and the substrate is provided in the substrate. A first pixel having a first photoelectric conversion unit and a first charge storage unit is formed, a second pixel having a second photoelectric conversion unit and a second charge storage unit is formed in the substrate, and a second pixel having a second photoelectric conversion unit and a second charge storage unit is formed in the substrate. A first light-shielding film is formed between the adjacent second photoelectric conversion unit and the first charge storage unit, a multilayer wiring layer is formed on the first surface side of the substrate, and the inside of the multilayer wiring layer is formed. Includes forming a second light-shielding film in contact with the first light-shielding film. As a result, for example, it is possible to suppress the formation of a gap between the first light-shielding film and the second light-shielding film, and it is possible to form a suitable light-shielding film.
　また、この第３の側面の固体撮像装置の製造方法は、前記基板を貫通する第１溝を形成することをさらに含み、前記第１遮光膜は、前記基板の前記第１面側から前記第１溝内に形成されてもよい。これにより例えば、第１溝内に第１遮光膜を埋め込むことで、基板内に第１遮光膜を形成することが可能となる。 Further, the method for manufacturing the solid-state image sensor on the third side surface further includes forming a first groove penetrating the substrate, and the first light-shielding film is the first from the first surface side of the substrate. It may be formed in one groove. This makes it possible to form the first light-shielding film in the substrate, for example, by embedding the first light-shielding film in the first groove.
　また、この第３の側面の固体撮像装置の製造方法は、前記基板の前記第２面上に、前記第１電荷蓄積部と平面視で重なり、前記第１遮光膜に接する第３遮光膜を形成することをさらに含んでいてもよい。これにより例えば、第１遮光膜と第３遮光膜との間に隙間が生じることを抑制することが可能となり、好適な遮光膜を形成することが可能となる。 Further, in the method of manufacturing the solid-state image sensor on the third side surface, a third light-shielding film that overlaps the first charge storage portion in a plan view and is in contact with the first light-shielding film is formed on the second surface of the substrate. It may further include forming. As a result, for example, it is possible to suppress the formation of a gap between the first light-shielding film and the third light-shielding film, and it is possible to form a suitable light-shielding film.
　また、この第３の側面の固体撮像装置の製造方法は、前記基板を貫通しない第２溝を形成することをさらに含み、前記第３遮光膜は、前記基板の前記第２面に形成され、かつ、前記基板の前記第２面側から前記第２溝内に形成されてもよい。これにより例えば、光電変換部から電荷蓄積部内に光が入り込むことを、第１遮光膜と第３遮光膜により抑制することが可能となる。 Further, the method for manufacturing the solid-state imaging device on the third side surface further includes forming a second groove that does not penetrate the substrate, and the third light-shielding film is formed on the second surface of the substrate. Moreover, it may be formed in the second groove from the second surface side of the substrate. This makes it possible, for example, to prevent light from entering the charge storage unit from the photoelectric conversion unit by the first light-shielding film and the third light-shielding film.
第１実施形態の固体撮像装置の構成を示すブロック図である。It is a block diagram which shows the structure of the solid-state image sensor of 1st Embodiment. 第１実施形態の固体撮像装置の構造を示す断面図である。It is sectional drawing which shows the structure of the solid-state image pickup apparatus of 1st Embodiment. 第１実施形態の固体撮像装置の構造を示す拡大断面図である。It is an enlarged sectional view which shows the structure of the solid-state image sensor of 1st Embodiment. 比較例の固体撮像装置の構造を示す断面図である。It is sectional drawing which shows the structure of the solid-state image sensor of the comparative example. 比較例の固体撮像装置の構造を示す拡大断面図である。It is an enlarged sectional view which shows the structure of the solid-state image sensor of the comparative example. 第１実施形態の固体撮像装置の製造方法を示す断面図(1/6)である。It is sectional drawing (1/6) which shows the manufacturing method of the solid-state image sensor of 1st Embodiment. 第１実施形態の固体撮像装置の製造方法を示す断面図(2/6)である。It is sectional drawing (2/6) which shows the manufacturing method of the solid-state image sensor of 1st Embodiment. 第１実施形態の固体撮像装置の製造方法を示す断面図(3/6)である。It is sectional drawing (3/6) which shows the manufacturing method of the solid-state image sensor of 1st Embodiment. 第１実施形態の固体撮像装置の製造方法を示す断面図(4/6)である。It is sectional drawing (4/6) which shows the manufacturing method of the solid-state image sensor of 1st Embodiment. 第１実施形態の固体撮像装置の製造方法を示す断面図(5/6)である。It is sectional drawing (5/6) which shows the manufacturing method of the solid-state image sensor of 1st Embodiment. 第１実施形態の固体撮像装置の製造方法を示す断面図(6/6)である。It is sectional drawing (6/6) which shows the manufacturing method of the solid-state image sensor of 1st Embodiment. 第１実施形態の変形例の固体撮像装置の製造方法を示す断面図(1/4)である。It is sectional drawing (1/4) which shows the manufacturing method of the solid-state image sensor of the modification of 1st Embodiment. 第１実施形態の変形例の固体撮像装置の製造方法を示す断面図(2/4)である。It is sectional drawing (2/4) which shows the manufacturing method of the solid-state image sensor of the modification of 1st Embodiment. 第１実施形態の変形例の固体撮像装置の製造方法を示す断面図(3/4)である。It is sectional drawing (3/4) which shows the manufacturing method of the solid-state image sensor of the modification of 1st Embodiment. 第１実施形態の変形例の固体撮像装置の製造方法を示す断面図(4/4)である。It is sectional drawing (4/4) which shows the manufacturing method of the solid-state image sensor of the modification of 1st Embodiment. 第１実施形態の固体撮像装置の構造を示す平面図である。It is a top view which shows the structure of the solid-state image sensor of 1st Embodiment. 第１実施形態の固体撮像装置の構造と、第１実施形態の変形例の固体撮像装置の構造とを示す断面図である。It is sectional drawing which shows the structure of the solid-state image pickup apparatus of 1st Embodiment, and the structure of the solid-state image pickup apparatus of the modification of 1st Embodiment. 電子機器の構成例を示すブロック図である。It is a block diagram which shows the structural example of an electronic device. 移動体制御システムの構成例を示すブロック図である。It is a block diagram which shows the configuration example of a mobile body control system. 図１９の撮像部の設定位置の具体例を示す平面図である。It is a top view which shows the specific example of the setting position of the image pickup part of FIG. 内視鏡手術システムの概略的な構成の一例を示す図である。It is a figure which shows an example of the schematic structure of an endoscopic surgery system. カメラヘッド及びＣＣＵの機能構成の一例を示すブロック図である。It is a block diagram which shows an example of the functional structure of a camera head and a CCU.
　以下、本開示の実施形態を、図面を参照して説明する。 Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.
　（第１実施形態）
　図１は、第１実施形態の固体撮像装置の構成を示すブロック図である。 (First Embodiment)
FIG. 1 is a block diagram showing a configuration of a solid-state image sensor according to the first embodiment.
　図１の固体撮像装置は、ＣＭＯＳ（Complementary Metal Oxide Semiconductor）型のイメージセンサであり、複数の画素１を有する画素アレイ領域２と、制御回路３と、垂直駆動回路４と、複数のカラム信号処理回路５と、水平駆動回路６と、出力回路７と、複数の垂直信号線８と、水平信号線９とを備えている。 The solid-state image sensor of FIG. 1 is a CMOS (Complementary Metal Oxide Semiconductor) type image sensor, which includes a pixel array region 2 having a plurality of pixels 1, a control circuit 3, a vertical drive circuit 4, and a plurality of column signal processes. It includes a circuit 5, a horizontal drive circuit 6, an output circuit 7, a plurality of vertical signal lines 8, and a horizontal signal line 9.
　各画素１は、光電変換部として機能するフォトダイオードと、画素トランジスタとして機能するＭＯＳトランジスタとを備えている。画素トランジスタの例は、転送トランジスタ、リセットトランジスタ、増幅トランジスタ、選択トランジスタなどである。これらの画素トランジスタは、いくつかの画素１により共有されていてもよい。 Each pixel 1 includes a photodiode that functions as a photoelectric conversion unit and a MOS transistor that functions as a pixel transistor. Examples of pixel transistors are transfer transistors, reset transistors, amplification transistors, selection transistors, and the like. These pixel transistors may be shared by some pixels 1.
　画素アレイ領域２は、２次元アレイ状に配置された複数の画素１を有している。画素アレイ領域２は、光を受光して光電変換を行い、光電変換により生成された信号電荷を増幅して出力する有効画素領域と、黒レベルの基準となる光学的黒を出力する黒基準画素領域とを含んでいる。一般に、黒基準画素領域は有効画素領域の外周部に配置されている。 The pixel array area 2 has a plurality of pixels 1 arranged in a two-dimensional array. The pixel array region 2 is an effective pixel region that receives light and performs photoelectric conversion to amplify and output the signal charge generated by the photoelectric conversion, and a black reference pixel that outputs optical black as a reference for the black level. Includes areas and. Generally, the black reference pixel region is arranged on the outer peripheral portion of the effective pixel region.
　制御回路３は、垂直同期信号、水平同期信号、マスタクロックなどに基づいて、垂直駆動回路４、カラム信号処理回路５、水平駆動回路６などの動作の基準となる種々の信号を生成する。制御回路３により生成される信号は、例えばクロック信号や制御信号であり、垂直駆動回路４、カラム信号処理回路５、水平駆動回路６などに入力される。 The control circuit 3 generates various signals that serve as reference for the operation of the vertical drive circuit 4, the column signal processing circuit 5, the horizontal drive circuit 6, etc., based on the vertical sync signal, the horizontal sync signal, the master clock, and the like. The signal generated by the control circuit 3 is, for example, a clock signal or a control signal, and is input to the vertical drive circuit 4, the column signal processing circuit 5, the horizontal drive circuit 6, and the like.
　垂直駆動回路４は、例えばシフトレジスタを備えており、画素アレイ領域２内の各画素１を行単位で垂直方向に走査する。垂直駆動回路４はさらに、各画素１が生成した信号電荷に基づく画素信号を、垂直信号線８を通してカラム信号処理回路５に供給する。 The vertical drive circuit 4 includes, for example, a shift register, and scans each pixel 1 in the pixel array area 2 in a row unit in the vertical direction. The vertical drive circuit 4 further supplies a pixel signal based on the signal charge generated by each pixel 1 to the column signal processing circuit 5 through the vertical signal line 8.
　カラム信号処理回路５は、例えば画素アレイ領域２内の画素１の列ごとに配置されており、１行分の画素１から出力された信号の信号処理を、黒基準画素領域からの信号に基づいて列ごとに行う。この信号処理の例は、ノイズ除去や信号増幅である。 The column signal processing circuit 5 is arranged, for example, for each column of the pixel 1 in the pixel array area 2, and the signal processing of the signal output from the pixel 1 for one row is based on the signal from the black reference pixel area. Do it for each row. Examples of this signal processing are denoising and signal amplification.
　水平駆動回路６は、例えばシフトレジスタを備えており、各カラム信号処理回路５からの画素信号を水平信号線９に供給する。 The horizontal drive circuit 6 includes, for example, a shift register, and supplies pixel signals from each column signal processing circuit 5 to the horizontal signal line 9.
　出力回路７は、各カラム信号処理回路５から水平信号線９を通して供給される信号に対し信号処理を行い、この信号処理が行われた信号を出力する。 The output circuit 7 performs signal processing on the signal supplied from each column signal processing circuit 5 through the horizontal signal line 9, and outputs the signal to which this signal processing has been performed.
　図２は、第１実施形態の固体撮像装置の構造を示す断面図である。図２は、図１の画素アレイ領域２の縦断面を示しており、具体的には、画素アレイ領域２内の３つの画素１の縦断面を示している。これらの画素１は、本開示の第１画素や第２画素の例である。 FIG. 2 is a cross-sectional view showing the structure of the solid-state image sensor of the first embodiment. FIG. 2 shows a vertical cross section of the pixel array region 2 of FIG. 1, specifically, shows a vertical cross section of three pixels 1 in the pixel array region 2. These pixels 1 are examples of the first pixel and the second pixel of the present disclosure.
　本実施形態の固体撮像装置は、基板１１と、複数の光電変換部１２と、各光電変換部１２に含まれるｐ＋型半導体領域１３、ｎ－型半導体領域１４、およびｐ型半導体領域１５と、複数のメモリ部１６と、各メモリ部１６に含まれるｐ＋型半導体領域１７、ｎ－型半導体領域１８、およびｐ型半導体領域１９と、基板１１内のその他の半導体領域２０とを備えている。これらの光電変換部１２は、本開示の第１光電変換部や第２光電変換部の例である。また、これらのメモリ部１６は、本開示の第１電荷蓄積部や第２電荷蓄積部の例である。 The solid-state imaging device of the present embodiment includes a substrate 11, a plurality of photoelectric conversion units 12, a p + type semiconductor region 13, an n-type semiconductor region 14, and a p-type semiconductor region 15 included in each photoelectric conversion unit 12. It includes a plurality of memory units 16, a p + type semiconductor region 17, an n− type semiconductor region 18, and a p-type semiconductor region 19 included in each memory unit 16, and another semiconductor region 20 in the substrate 11. These photoelectric conversion units 12 are examples of the first photoelectric conversion unit and the second photoelectric conversion unit of the present disclosure. Further, these memory units 16 are examples of the first charge storage unit and the second charge storage unit of the present disclosure.
　本実施形態の固体撮像装置はさらに、複数の溝２１と、各溝２１内に設けられた絶縁膜２２および遮光膜２３と、複数の溝２４（図２はそのうちの１つを示す）と、各溝２４内などに設けられた第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７と、平坦化膜２８と、複数のカラーフィルタ２９と、複数のオンチップレンズ３０とを備えている。溝２１は、本開示の第１溝の例であり、溝２４は、本開示の第２溝の例である。遮光膜２３は、本開示の第１遮光膜の例であり、遮光膜２７は、本開示の第３遮光膜の例である。 The solid-state image pickup device of the present embodiment further includes a plurality of grooves 21, an insulating film 22 and a light-shielding film 23 provided in each groove 21, and a plurality of grooves 24 (FIG. 2 shows one of them). A first insulating film 25, a second insulating film 26, and a light-shielding film 27 provided in each groove 24 or the like, a flattening film 28, a plurality of color filters 29, and a plurality of on-chip lenses 30 are provided. There is. The groove 21 is an example of the first groove of the present disclosure, and the groove 24 is an example of the second groove of the present disclosure. The light-shielding film 23 is an example of the first light-shielding film of the present disclosure, and the light-shielding film 27 is an example of the third light-shielding film of the present disclosure.
　本実施形態の固体撮像装置はさらに、ゲート絶縁膜として機能する絶縁層３１と、層間絶縁膜３２と、ゲート電極として機能する電極層３３と、各溝２１の付近などに設けられた遮光膜３４と、複数のコンタクトプラグ３５と、複数の配線層３６、３７、３８、３９と、複数のビアプラグ４０と、支持基板４１とを備えている。遮光膜３４は、本開示の第２遮光膜の例である。また、絶縁層３１、層間絶縁膜３２、電極層３３、遮光膜３４、コンタクトプラグ３５、配線層３６～３９、およびビアプラグ４０を含む層４２は、本開示の多層配線層の例である。 The solid-state imaging device of the present embodiment further includes an insulating layer 31 that functions as a gate insulating film, an interlayer insulating film 32, an electrode layer 33 that functions as a gate electrode, and a light-shielding film 34 provided in the vicinity of each groove 21. A plurality of contact plugs 35, a plurality of wiring layers 36, 37, 38, 39, a plurality of via plugs 40, and a support substrate 41 are provided. The light-shielding film 34 is an example of the second light-shielding film of the present disclosure. Further, the layer 42 including the insulating layer 31, the interlayer insulating film 32, the electrode layer 33, the light-shielding film 34, the contact plug 35, the wiring layers 36 to 39, and the via plug 40 is an example of the multilayer wiring layer of the present disclosure.
　図２は、互いに垂直なＸ軸、Ｙ軸、およびＺ軸を示している。Ｘ方向およびＹ方向は横方向（水平方向）に相当し、Ｚ方向は縦方向（垂直方向）に相当する。また、＋Ｚ方向は上方向に相当し、－Ｚ方向は下方向に相当する。－Ｚ方向は、厳密に重力方向に一致していてもよいし、厳密には重力方向に一致していなくてもよい。 FIG. 2 shows the X-axis, Y-axis, and Z-axis that are perpendicular to each other. The X and Y directions correspond to the horizontal direction (horizontal direction), and the Z direction corresponds to the vertical direction (vertical direction). Further, the + Z direction corresponds to the upward direction, and the −Z direction corresponds to the downward direction. The −Z direction may or may not exactly coincide with the direction of gravity.
　以下、図２を参照し、本実施形態の固体撮像装置の構造について説明する。この説明の中で、図３も適宜参照する。図３は、第１実施形態の固体撮像装置の構造を示す拡大断面図である。 Hereinafter, the structure of the solid-state image sensor of the present embodiment will be described with reference to FIG. In this description, FIG. 3 will also be referred to as appropriate. FIG. 3 is an enlarged cross-sectional view showing the structure of the solid-state image sensor of the first embodiment.
　基板１１は例えば、シリコン（Ｓｉ）基板などの半導体基板である。図２は、基板１１の表面Ｓ１および裏面Ｓ２を示している。図２では、基板１１の表面Ｓ１は、基板１１の－Ｚ方向の面（下面）であり、基板１１の裏面Ｓ２は、基板１１の＋Ｚ方向の面（上面）である。本実施形態の固体撮像装置は、裏面照射型であるため、基板１１の裏面Ｓ２が、基板１１の光入射面（受光面）となる。基板１１の表面Ｓ１は、本開示の第１面の例であり、基板１１の裏面Ｓ２は、本開示の第２面の例である。 The substrate 11 is, for example, a semiconductor substrate such as a silicon (Si) substrate. FIG. 2 shows the front surface S1 and the back surface S2 of the substrate 11. In FIG. 2, the front surface S1 of the substrate 11 is a surface (lower surface) in the −Z direction of the substrate 11, and the back surface S2 of the substrate 11 is a surface (upper surface) in the + Z direction of the substrate 11. Since the solid-state image sensor of this embodiment is a back-illuminated type, the back surface S2 of the substrate 11 is the light incident surface (light receiving surface) of the substrate 11. The front surface S1 of the substrate 11 is an example of the first surface of the present disclosure, and the back surface S2 of the substrate 11 is an example of the second surface of the present disclosure.
　光電変換部１２は、基板１１内に画素１ごとに設けられている。各光電変換部１２は、基板１１の表面Ｓ１側から裏面Ｓ２側へと基板１１内に順に形成されたｐ＋型半導体領域１３と、ｎ－型半導体領域１４と、ｐ型半導体領域１５とを備えている。光電変換部１２では、ｐ＋型半導体領域１３とｎ－型半導体領域１４との間のｐｎ接合や、ｎ－型半導体領域１４とｐ型半導体領域１５との間のｐｎ接合により、フォトダイオードが実現されており、フォトダイオードが光を電荷に変換する。光電変換部１２は、基板１１の裏面Ｓ２側から光を受光し、受光した光の光量に応じた信号電荷を生成し、生成した信号電荷をｎ－型半導体領域１４に蓄積する。 The photoelectric conversion unit 12 is provided in the substrate 11 for each pixel 1. Each photoelectric conversion unit 12 includes a p + type semiconductor region 13 formed in the substrate 11 in order from the front surface S1 side to the back surface S2 side of the substrate 11, an n− type semiconductor region 14, and a p-type semiconductor region 15. ing. In the photoelectric conversion unit 12, a photodiode is realized by a pn junction between the p + type semiconductor region 13 and the n-type semiconductor region 14 and a pn junction between the n-type semiconductor region 14 and the p-type semiconductor region 15. And the photodiode converts light into a charge. The photoelectric conversion unit 12 receives light from the back surface S2 side of the substrate 11, generates a signal charge according to the amount of the received light, and stores the generated signal charge in the n-type semiconductor region 14.
　メモリ部１６も、基板１１内に画素１ごとに設けられている。各メモリ部１６は、基板１１の表面Ｓ１側から裏面Ｓ２側へと基板１１内に順に形成されたｐ＋型半導体領域１７と、ｎ－型半導体領域１８と、ｐ型半導体領域１９とを備えている。ただし、ｐ＋型半導体領域１７、ｎ－型半導体領域１８、およびｐ型半導体領域１９のＺ方向の合計厚は、ｐ＋型半導体領域１３、ｎ－型半導体領域１４、およびｐ型半導体領域１５のＺ方向の合計厚よりも薄くなっている。各画素１内のメモリ部１６は、同じ画素１内の光電変換部１２から転送された信号電荷を蓄積する。 The memory unit 16 is also provided in the substrate 11 for each pixel 1. Each memory unit 16 includes a p + type semiconductor region 17 formed in the substrate 11 in order from the front surface S1 side to the back surface S2 side of the substrate 11, an n− type semiconductor region 18, and a p-type semiconductor region 19. There is. However, the total thickness of the p + type semiconductor region 17, the n-type semiconductor region 18, and the p-type semiconductor region 19 in the Z direction is the Z of the p + type semiconductor region 13, the n-type semiconductor region 14, and the p-type semiconductor region 15. It is thinner than the total thickness in the direction. The memory unit 16 in each pixel 1 accumulates the signal charge transferred from the photoelectric conversion unit 12 in the same pixel 1.
　基板１１内のその他の半導体領域２０は例えば、後述する浮遊拡散部ＦＤなどを含んでいる（図１６参照）。 The other semiconductor region 20 in the substrate 11 includes, for example, a floating diffusion portion FD described later (see FIG. 16).
　溝２１は、基板１１内および絶縁層３１内に設けられており、基板１１と絶縁層３１とを貫通している。各溝２１は、基板１１内にて、互いに隣接する光電変換部１２とメモリ部１６との間に設けられている。図２に示す各溝２１は、異なる画素１内の光電変換部１２とメモリ部１６との間に設けられているが、本実施形態の各溝２１は、同じ画素１内の光電変換部１２とメモリ部１６との間に設けられていてもよい。 The groove 21 is provided in the substrate 11 and the insulating layer 31, and penetrates the substrate 11 and the insulating layer 31. Each groove 21 is provided in the substrate 11 between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other. Each groove 21 shown in FIG. 2 is provided between the photoelectric conversion unit 12 and the memory unit 16 in different pixels 1, but each groove 21 of the present embodiment has the photoelectric conversion unit 12 in the same pixel 1. It may be provided between the memory unit 16 and the memory unit 16.
　溝２１は例えば、基板１１の表面Ｓ１側から基板１１内にドライエッチングにより凹部を形成することで形成される。よって、本実施形態の溝２１のＸ方向の幅は、基板の表面Ｓ１側から裏面Ｓ２側に進むにつれ狭くなっている。本実施形態の溝２１は、Ｙ方向およびＺ方向に延びる形状を有している。溝２１を形成する際には例えば、上述のドライエッチングにより絶縁層３１および基板１１が順に加工され、その結果、絶縁層３１から基板１１に達する溝２１が形成される。 The groove 21 is formed, for example, by forming a recess in the substrate 11 from the surface S1 side of the substrate 11 by dry etching. Therefore, the width of the groove 21 of the present embodiment in the X direction becomes narrower from the front surface S1 side to the back surface S2 side of the substrate. The groove 21 of the present embodiment has a shape extending in the Y direction and the Z direction. When forming the groove 21, for example, the insulating layer 31 and the substrate 11 are sequentially processed by the above-mentioned dry etching, and as a result, the groove 21 reaching from the insulating layer 31 to the substrate 11 is formed.
　絶縁膜２２および遮光膜２３は、各溝２１内に順に形成されている。具体的には、絶縁膜２２は、各溝２１内で基板１１および絶縁層３１の側面に形成されており、遮光膜２３は、各溝２１内に絶縁膜２２を介して埋め込まれている。絶縁膜２２は例えば、基板１１および絶縁層３１を酸化させて形成された酸化シリコン膜（ＳｉＯ２膜）である。遮光膜２３は例えば、タングステン（Ｗ）、アルミニウム（Ａｌ）、または銅（Ｃｕ）といった金属元素を含む膜であり、光を遮光する作用を有する。 The insulating film 22 and the light-shielding film 23 are sequentially formed in each groove 21. Specifically, the insulating film 22 is formed on the side surface of the substrate 11 and the insulating layer 31 in each groove 21, and the light-shielding film 23 is embedded in each groove 21 via the insulating film 22. The insulating film 22 is, for example, a silicon oxide film (SiO 2 film) formed by oxidizing the substrate 11 and the insulating layer 31. The light-shielding film 23 is a film containing a metal element such as tungsten (W), aluminum (Al), or copper (Cu), and has an effect of blocking light.
　本実施形態の遮光膜２３の形状は、溝２１の形状とおおむね同じである。よって、本実施形態の遮光膜２３のＸ方向の幅は、基板の表面Ｓ１側から裏面Ｓ２側に進むにつれ狭くなっている。また、本実施形態の遮光膜２３は、Ｙ方向およびＺ方向に延びる形状を有している。図２に示す符号Ｗは、遮光膜２３のＸ方向の幅を示している。溝２１、絶縁膜２２、および遮光膜２３の形状は、図３にも示されている。図３は、遮光膜２３の幅Ｗの例として、遮光膜２３の下端付近における遮光膜２３の幅Ｗ１と、遮光膜２３の上端付近における遮光膜２３の幅Ｗ２とを示している（Ｗ２＜Ｗ１）。 The shape of the light-shielding film 23 of this embodiment is almost the same as the shape of the groove 21. Therefore, the width of the light-shielding film 23 of the present embodiment in the X direction becomes narrower from the front surface S1 side to the back surface S2 side of the substrate. Further, the light-shielding film 23 of the present embodiment has a shape extending in the Y direction and the Z direction. The reference numeral W shown in FIG. 2 indicates the width of the light-shielding film 23 in the X direction. The shapes of the groove 21, the insulating film 22, and the light-shielding film 23 are also shown in FIG. FIG. 3 shows, as an example of the width W of the light-shielding film 23, the width W1 of the light-shielding film 23 near the lower end of the light-shielding film 23 and the width W2 of the light-shielding film 23 near the upper end of the light-shielding film 23 (W2 <. W1).
　溝２４は、基板１１内に設けられており、基板１１を貫通していない。各溝２４は、基板１１内にて、互いに隣接する光電変換部１２とメモリ部１６との間に設けられている。図２に示す溝２４は、同じ画素１内の光電変換部１２とメモリ部１６との間に設けられているが、本実施形態の各溝２４は、異なる画素１内の光電変換部１２とメモリ部１６との間に設けられていてもよい。 The groove 24 is provided in the substrate 11 and does not penetrate the substrate 11. Each groove 24 is provided in the substrate 11 between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other. The groove 24 shown in FIG. 2 is provided between the photoelectric conversion unit 12 and the memory unit 16 in the same pixel 1, but each groove 24 of the present embodiment has a photoelectric conversion unit 12 in different pixels 1. It may be provided between the memory unit 16 and the memory unit 16.
　溝２４は例えば、基板１１の裏面Ｓ２側から基板１１内にドライエッチングにより凹部を形成することで形成される。よって、本実施形態の溝２４のＸ方向の幅は、基板の表面Ｓ１側から裏面Ｓ２側に進むにつれ広くなっている。本実施形態の溝２４は、Ｙ方向およびＺ方向に延びる形状を有している。溝２４を形成する際には例えば、上述のドライエッチングにより基板１１の裏面側Ｓ２から基板１１内に、基板１１を貫通しないように溝２４が形成される。 The groove 24 is formed, for example, by forming a recess in the substrate 11 from the back surface S2 side of the substrate 11 by dry etching. Therefore, the width of the groove 24 of the present embodiment in the X direction becomes wider from the front surface S1 side to the back surface S2 side of the substrate. The groove 24 of the present embodiment has a shape extending in the Y direction and the Z direction. When forming the groove 24, for example, the groove 24 is formed from the back surface side S2 of the substrate 11 into the substrate 11 by the above-mentioned dry etching so as not to penetrate the substrate 11.
　第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７は、基板１１の裏面Ｓ２や、基板１１の各溝２４内に順に形成されている。具体的には、第１絶縁膜２５および第２絶縁膜２６は、各溝２４内で基板１１の側面および底面に順に形成されており、遮光膜２７は、各溝２４内に第１絶縁膜２５および第２絶縁膜２６を介して埋め込まれている。さらに、第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７は、溝２４の外部で基板１１の裏面Ｓ２に順に積層されている。ただし、第１絶縁膜２５および第２絶縁膜２６は、遮光膜２３上に開口部を有しており、遮光膜２７は、この開口部内に埋め込まれている。よって、遮光膜２７は、この開口部内で遮光膜２３に接している。第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７の形状は、図３にも示されている。 The first insulating film 25, the second insulating film 26, and the light-shielding film 27 are sequentially formed in the back surface S2 of the substrate 11 and in each groove 24 of the substrate 11. Specifically, the first insulating film 25 and the second insulating film 26 are sequentially formed on the side surface and the bottom surface of the substrate 11 in each groove 24, and the light-shielding film 27 is a first insulating film in each groove 24. It is embedded via the 25 and the second insulating film 26. Further, the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are sequentially laminated on the back surface S2 of the substrate 11 outside the groove 24. However, the first insulating film 25 and the second insulating film 26 have an opening on the light-shielding film 23, and the light-shielding film 27 is embedded in the opening. Therefore, the light-shielding film 27 is in contact with the light-shielding film 23 within this opening. The shapes of the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are also shown in FIG.
　第１絶縁膜２５は例えば、負の固定電荷を有する固定電荷膜である。固定電荷膜は、基板１１の界面に存在する微小欠陥に起因して暗電流と呼ばれるノイズが発生することを抑制する作用を有する。固定電荷膜は例えば、ハフニウム（Ｈｆ）、アルミニウム（Ａｌ）、ジルコニウム（Ｚｒ）、タンタル（Ｔａ）、またはチタン（Ｔｉ）といった金属元素を含む酸化膜または窒化膜である。第２絶縁膜２６は例えば、酸化シリコン膜（ＳｉＯ２膜）、窒化シリコン膜（ＳｉＮ膜）、酸窒化シリコン膜（ＳｉＯＮ膜）、または樹脂膜である。第１絶縁膜２５および第２絶縁膜２６は例えば、ＡＬＤ（Atomic Layer Deposition）により形成される。遮光膜２７は例えば、タングステン（Ｗ）、アルミニウム（Ａｌ）、または銅（Ｃｕ）といった金属元素を含む膜であり、光を遮光する作用を有する。 The first insulating film 25 is, for example, a fixed charge film having a negative fixed charge. The fixed charge film has an effect of suppressing the generation of noise called dark current due to minute defects existing at the interface of the substrate 11. The fixed charge film is, for example, an oxide film or a nitride film containing a metal element such as hafnium (Hf), aluminum (Al), zirconium (Zr), tantalum (Ta), or titanium (Ti). The second insulating film 26 is, for example, a silicon oxide film (SiO 2 film), a silicon nitride film (SiN film), a silicon nitride film (SiON film), or a resin film. The first insulating film 25 and the second insulating film 26 are formed by, for example, ALD (Atomic Layer Deposition). The light-shielding film 27 is a film containing a metal element such as tungsten (W), aluminum (Al), or copper (Cu), and has an effect of blocking light.
　本実施形態の溝２４内の遮光膜２７の形状は、溝２４の形状とおおむね同じである。よって、本実施形態の遮光膜２７のＸ方向の幅は、基板の表面Ｓ１側から裏面Ｓ２側に進むにつれ広くなっている。また、本実施形態の遮光膜２７は、Ｙ方向およびＺ方向に延びる形状を有している。一方、本実施形態の溝２４外の遮光膜２７は、メモリ部１６と平面視で重なる位置に設けられている。 The shape of the light-shielding film 27 in the groove 24 of the present embodiment is substantially the same as the shape of the groove 24. Therefore, the width of the light-shielding film 27 of the present embodiment in the X direction becomes wider from the front surface S1 side to the back surface S2 side of the substrate. Further, the light-shielding film 27 of the present embodiment has a shape extending in the Y direction and the Z direction. On the other hand, the light-shielding film 27 outside the groove 24 of the present embodiment is provided at a position where it overlaps with the memory unit 16 in a plan view.
　平坦化膜２８は、基板１１の裏面Ｓ２を覆うように基板１１上に第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７を介して形成されており、これにより基板１１の裏面Ｓ２上の面が平坦となっている。平坦化膜２８は例えば、樹脂膜などの有機膜である。 The flattening film 28 is formed on the substrate 11 via a first insulating film 25, a second insulating film 26, and a light-shielding film 27 so as to cover the back surface S2 of the substrate 11, whereby the back surface S2 of the substrate 11 is formed. The upper surface is flat. The flattening film 28 is, for example, an organic film such as a resin film.
　カラーフィルタ２９は、所定の波長の光を透過させる作用を有し、平坦化膜２８上に画素１ごとに形成されている。例えば、赤色（Ｒ）、緑色（Ｇ）、青色（Ｂ）用のカラーフィルタ２９がそれぞれ、赤色、緑色、青色の画素１の光電変換部１２の上方に配置されている。さらに、赤外光用のカラーフィルタ２９が、赤外光の画素１の光電変換部１２の上方に配置されていてもよい。各カラーフィルタ２９を透過した光は、平坦化膜２８を介して光電変換部１２に入射する。 The color filter 29 has a function of transmitting light having a predetermined wavelength, and is formed on the flattening film 28 for each pixel 1. For example, the color filters 29 for red (R), green (G), and blue (B) are arranged above the photoelectric conversion unit 12 of the red, green, and blue pixels 1, respectively. Further, the color filter 29 for infrared light may be arranged above the photoelectric conversion unit 12 of the infrared light pixel 1. The light transmitted through each color filter 29 is incident on the photoelectric conversion unit 12 via the flattening film 28.
　オンチップレンズ３０は、入射した光を集光する作用を有し、カラーフィルタ２９上に画素１ごとに形成されている。各オンチップレンズ３０により集光された光は、カラーフィルタ２９と平坦化膜２８とを介して光電変換部１２に入射する。本実施形態の各オンチップレンズ３０は、光が透過する材料で形成されており、オンチップレンズ３７同士は、この材料を介して互いにつながっている。 The on-chip lens 30 has a function of condensing incident light, and is formed on the color filter 29 for each pixel 1. The light collected by each on-chip lens 30 is incident on the photoelectric conversion unit 12 via the color filter 29 and the flattening film 28. Each on-chip lens 30 of the present embodiment is made of a material through which light is transmitted, and the on-chip lenses 37 are connected to each other via this material.
　絶縁層３１は、基板１１の表面Ｓ１に形成されており、各画素トランジスタのゲート絶縁膜として機能する。図２は、後述する転送トランジスタＴＲＹのゲート絶縁膜の断面を示している（図１６参照）。絶縁層３１は例えば、図３に示すように、基板１１の表面Ｓ１に順に積層された第１絶縁膜３１ａ、第２絶縁膜３１ｂ、および第３絶縁膜３１ｃを含む積層膜である。第１絶縁膜３１ａは例えば、酸化シリコン膜（ＳｉＯ２膜）である。第２絶縁膜３１ｂは例えば、窒化シリコン膜（ＳｉＮ膜）である。第３絶縁膜３１ｃは例えば、酸化シリコン膜（ＳｉＯ２膜）である。 The insulating layer 31 is formed on the surface S1 of the substrate 11 and functions as a gate insulating film of each pixel transistor. FIG. 2 shows a cross section of the gate insulating film of the transfer transistor TRY, which will be described later (see FIG. 16). As shown in FIG. 3, the insulating layer 31 is, for example, a laminated film including a first insulating film 31a, a second insulating film 31b, and a third insulating film 31c laminated in order on the surface S1 of the substrate 11. The first insulating film 31a is, for example, a silicon oxide film (SiO 2 film). The second insulating film 31b is, for example, a silicon nitride film (SiN film). The third insulating film 31c is, for example, a silicon oxide film (SiO 2 film).
　層間絶縁膜３２は、基板１１の表面Ｓ１に絶縁層３１、電極層３３、および遮光膜３４を覆うように形成されている。層間絶縁膜３２は例えば、酸化シリコン膜（ＳｉＯ２膜）とその他の絶縁膜とを含む積層膜である。 The interlayer insulating film 32 is formed on the surface S1 of the substrate 11 so as to cover the insulating layer 31, the electrode layer 33, and the light-shielding film 34. The interlayer insulating film 32 is, for example, a laminated film including a silicon oxide film (SiO 2 film) and another insulating film.
　電極層３３は、基板１１の表面Ｓ１に絶縁層３１を介して形成されており、各画素トランジスタのゲート電極として機能する。図２は、後述する転送トランジスタＴＲＹのゲート電極の断面を示している（図１６参照）。電極層３３は例えば、ポリシリコン層または金属層である。 The electrode layer 33 is formed on the surface S1 of the substrate 11 via the insulating layer 31, and functions as a gate electrode of each pixel transistor. FIG. 2 shows a cross section of the gate electrode of the transfer transistor TRY, which will be described later (see FIG. 16). The electrode layer 33 is, for example, a polysilicon layer or a metal layer.
　遮光膜３４は、基板１１の表面Ｓ１に絶縁層３１および電極層３３を介して形成されており、電極層３３に接している。また、上述のように遮光膜２３が絶縁層３１を貫通していることから、遮光膜３４は、遮光膜２３の下面にて遮光膜２３に接している。これにより、本実施形態の遮光膜３４は、遮光膜２３を介して遮光膜２７と電気的に接続されている。遮光膜３４は例えば、タングステン（Ｗ）、アルミニウム（Ａｌ）、または銅（Ｃｕ）といった金属元素を含む膜であり、光を遮光する作用を有する。 The light-shielding film 34 is formed on the surface S1 of the substrate 11 via the insulating layer 31 and the electrode layer 33, and is in contact with the electrode layer 33. Further, since the light-shielding film 23 penetrates the insulating layer 31 as described above, the light-shielding film 34 is in contact with the light-shielding film 23 on the lower surface of the light-shielding film 23. As a result, the light-shielding film 34 of the present embodiment is electrically connected to the light-shielding film 27 via the light-shielding film 23. The light-shielding film 34 is a film containing a metal element such as tungsten (W), aluminum (Al), or copper (Cu), and has an effect of blocking light.
　なお、遮光膜３４は、本実施形態では後述するように遮光膜２３とは異なる工程で形成されるが、遮光膜２３と同じ工程で形成されてもよい。この場合の遮光膜２３および遮光膜３４もそれぞれ、本開示の第１および第２遮光膜の例である。また、基板１１外の遮光膜２７は、本実施形態では基板１１内の遮光膜２７と同じ工程で形成されるが、基板１１内の遮光膜２７と異なる工程で形成されてもよい。この場合の基板１１内の遮光膜２７と基板１１外の遮光膜２７も、本開示の第３遮光膜の例である。 Although the light-shielding film 34 is formed in a different process from the light-shielding film 23 as described later in the present embodiment, the light-shielding film 34 may be formed in the same process as the light-shielding film 23. The light-shielding film 23 and the light-shielding film 34 in this case are also examples of the first and second light-shielding films of the present disclosure, respectively. Further, the light-shielding film 27 outside the substrate 11 is formed in the same process as the light-shielding film 27 inside the substrate 11 in the present embodiment, but may be formed in a different process from the light-shielding film 27 inside the substrate 11. The light-shielding film 27 inside the substrate 11 and the light-shielding film 27 outside the substrate 11 in this case are also examples of the third light-shielding film of the present disclosure.
　配線層３６～３９は、基板１１の表面Ｓ１に順に設けられており、多層配線構造を形成している。具体的には、配線層３６～３９は、層間絶縁膜３２内に設けられており、絶縁層３１、電極層３３、および遮光膜３４の下方に配置されている。コンタクトプラグ３５は、配線層３６と電極層３３との間や、配線層３６と遮光膜３４との間を電気的に接続している。ビアプラグ４０は、配線層３６～３９の間を電気的に接続している。本実施形態の多層配線構造は、４層の配線層３６～３９を含んでいるが、３層以下または５層以上の配線層を含んでいてもよい。配線層３６～３９の各々は種々の配線を含んでおり、各画素トランジスタはこれらの配線を用いて駆動される。 The wiring layers 36 to 39 are sequentially provided on the surface S1 of the substrate 11 to form a multi-layer wiring structure. Specifically, the wiring layers 36 to 39 are provided in the interlayer insulating film 32, and are arranged below the insulating layer 31, the electrode layer 33, and the light-shielding film 34. The contact plug 35 electrically connects between the wiring layer 36 and the electrode layer 33, and between the wiring layer 36 and the light-shielding film 34. The via plug 40 electrically connects between the wiring layers 36 to 39. The multilayer wiring structure of the present embodiment includes four wiring layers 36 to 39, but may include three or less or five or more wiring layers. Each of the wiring layers 36 to 39 contains various wirings, and each pixel transistor is driven by using these wirings.
　支持基板４１は、基板１１の表面Ｓ１に層間絶縁膜３２などを介して設けられており、基板１１の強度を確保するために設けられている。支持基板４１は例えば、シリコン（Ｓｉ）基板などの半導体基板である。 The support substrate 41 is provided on the surface S1 of the substrate 11 via an interlayer insulating film 32 or the like, and is provided to ensure the strength of the substrate 11. The support substrate 41 is, for example, a semiconductor substrate such as a silicon (Si) substrate.
　層４２は、絶縁層３１、層間絶縁膜３２、電極層３３、遮光膜３４、コンタクトプラグ３５、配線層３６～３９、およびビアプラグ４０を含んでいる。本実施形態の層４２は、配線層３６～３９により形成された多層配線構造を含む多層配線層となっている。 The layer 42 includes an insulating layer 31, an interlayer insulating film 32, an electrode layer 33, a light-shielding film 34, a contact plug 35, wiring layers 36 to 39, and a via plug 40. The layer 42 of the present embodiment is a multi-layer wiring layer including a multi-layer wiring structure formed by the wiring layers 36 to 39.
　本実施形態では、オンチップレンズ３０に入射した光が、オンチップレンズ３０により集光され、カラーフィルタ２９を透過し、光電変換部１２へと入射する。光電変換部１２は、この光を光電変換により電荷に変換して、信号電荷を生成する。信号電荷は、配線層３６～３９内の垂直信号線８を介して、画素信号として出力される。 In the present embodiment, the light incident on the on-chip lens 30 is collected by the on-chip lens 30, passes through the color filter 29, and is incident on the photoelectric conversion unit 12. The photoelectric conversion unit 12 converts this light into an electric charge by photoelectric conversion to generate a signal charge. The signal charge is output as a pixel signal via the vertical signal line 8 in the wiring layers 36 to 39.
　図４は、比較例の固体撮像装置の構造を示す断面図である。図４は、図１の画素アレイ領域２の縦断面を示しており、具体的には、画素アレイ領域２内の３つの画素１の縦断面を示している。 FIG. 4 is a cross-sectional view showing the structure of the solid-state image sensor of the comparative example. FIG. 4 shows a vertical cross section of the pixel array region 2 of FIG. 1, specifically, shows a vertical cross section of three pixels 1 in the pixel array region 2.
　以下、図４を参照して、本比較例の固体撮像装置の構造について説明する。この説明の中で、図５も適宜参照する。図５は、本比較例の固体撮像装置の構造を示す拡大断面図である。 Hereinafter, the structure of the solid-state image sensor of this comparative example will be described with reference to FIG. In this description, FIG. 5 is also referred to as appropriate. FIG. 5 is an enlarged cross-sectional view showing the structure of the solid-state image sensor of this comparative example.
　本比較例の溝２１は、溝２４と同様に、基板１１の裏面Ｓ２側から基板１１内に形成されており、第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７により満たされている。また、本比較例の溝２１は、基板１１は貫通しているが、絶縁層３１は貫通していない。具体的には、本比較例の溝２１は、図５に示すように、第２絶縁膜３１ｂには達しているが、第３絶縁膜３１ｃには達しておらず、その結果、遮光膜３４には接していない。 Similar to the groove 24, the groove 21 of this comparative example is formed in the substrate 11 from the back surface S2 side of the substrate 11 and is filled with the first insulating film 25, the second insulating film 26, and the light-shielding film 27. There is. Further, the groove 21 of this comparative example penetrates the substrate 11, but does not penetrate the insulating layer 31. Specifically, as shown in FIG. 5, the groove 21 of this comparative example reaches the second insulating film 31b but does not reach the third insulating film 31c, and as a result, the light-shielding film 34 Not in contact with.
　次に、図２から図５を参照して、第１実施形態の固体撮像装置と、本比較例の固体撮像装置とを比較する。 Next, with reference to FIGS. 2 to 5, the solid-state image sensor of the first embodiment is compared with the solid-state image sensor of this comparative example.
　本比較例では、溝２１が絶縁層３１を貫通していないことから、図４や図５に示すように、溝２１内の遮光膜２７と、基板１１の表面Ｓ１の遮光膜３４との間に、遮光膜が存在しない隙間が存在する。この隙間は、絶縁層３１、第１絶縁膜２５、および第２絶縁膜２６で満たされているため、この隙間を光が透過することができる。その結果、この隙間からメモリ部１６内に光が入り込み、ＰＬＳ特性が悪化してしまう。また、一部の隙間で溝２１が第２絶縁膜３１ｂを貫通してしまうと（ＳｉＮブレイク）、ＳｉＮブレイクの生じた箇所と、ＳｉＮブレイクの生じなかった箇所との間で、固体撮像装置の白色特性のばらつきが生じてしまう。また、本比較例の溝２１の側面を覆う絶縁膜は、ＡＬＤにより形成される第１絶縁膜２５および第２絶縁膜２６であるため、溝２１の側面を覆う絶縁膜を薄膜化しにくいことが問題となる。その結果、溝２１のサイズを大きくして、光電変換部１２のサイズを小さくする必要が生じ、飽和信号量が減少してしまう。 In this comparative example, since the groove 21 does not penetrate the insulating layer 31, as shown in FIGS. 4 and 5, between the light-shielding film 27 in the groove 21 and the light-shielding film 34 on the surface S1 of the substrate 11. There is a gap in which the light-shielding film does not exist. Since this gap is filled with the insulating layer 31, the first insulating film 25, and the second insulating film 26, light can pass through the gap. As a result, light enters the memory unit 16 through this gap, and the PLS characteristics deteriorate. Further, when the groove 21 penetrates the second insulating film 31b in a part of the gap (SiN break), the solid-state image sensor is used between the portion where the SiN break occurs and the portion where the SiN break does not occur. Variations in white characteristics will occur. Further, since the insulating film covering the side surface of the groove 21 of this comparative example is the first insulating film 25 and the second insulating film 26 formed by ALD, it is difficult to thin the insulating film covering the side surface of the groove 21. It becomes a problem. As a result, it becomes necessary to increase the size of the groove 21 and reduce the size of the photoelectric conversion unit 12, and the amount of saturation signal decreases.
　なお、本比較例の溝２１が絶縁層３１を貫通すると、次のような問題が生じる。本比較例では、基板１１の表面Ｓ１に遮光膜３４を形成した後に、基板１１の裏面Ｓ２側から基板１１内に溝２１を形成する。この場合、溝２１が絶縁層３１を貫通して遮光膜３４に達していると、溝２１内が熱リン酸水溶液などの薬液で処理される際に、遮光膜３４が薬液にさらされてしまう。その結果、遮光膜３４が薬液によりダメージを受けるという問題が生じる。よって、本比較例の溝２１は、絶縁層３１を貫通しないように形成される。 If the groove 21 of this comparative example penetrates the insulating layer 31, the following problems occur. In this comparative example, after the light-shielding film 34 is formed on the front surface S1 of the substrate 11, the groove 21 is formed in the substrate 11 from the back surface S2 side of the substrate 11. In this case, if the groove 21 penetrates the insulating layer 31 and reaches the light-shielding film 34, the light-shielding film 34 is exposed to the chemical solution when the inside of the groove 21 is treated with a chemical solution such as a thermal phosphoric acid aqueous solution. .. As a result, there arises a problem that the light-shielding film 34 is damaged by the chemical solution. Therefore, the groove 21 of this comparative example is formed so as not to penetrate the insulating layer 31.
　一方、本実施形態の溝２１は、基板１１および絶縁層３１を貫通していることから、図２や図３に示すように、溝２１内の遮光膜２３と、基板１１の表面Ｓ１の遮光膜３４との間に、遮光膜が存在しない隙間が存在しない。よって、隙間からメモリ部１６内に光が入り込む現象を抑制することが可能となる。また、各溝２１が第２絶縁膜３１ｂを貫通するように形成されるため、ＳｉＮブレイクに起因する白色特性のばらつきを抑制することが可能となる。また、本実施形態の溝２１の側面を覆う絶縁膜は、酸化により形成される絶縁膜２２であるため、溝２１の側面を覆う絶縁膜を容易に薄膜化することが可能となる。また、本実施形態の第１絶縁膜２５および第２絶縁膜２６は、溝２１内に形成する必要がないため、溝２１のサイズを考慮せずに第１絶縁膜２５および第２絶縁膜２６の膜厚を調整することが可能となる。 On the other hand, since the groove 21 of the present embodiment penetrates the substrate 11 and the insulating layer 31, as shown in FIGS. 2 and 3, the light-shielding film 23 in the groove 21 and the surface S1 of the substrate 11 are shielded from light. There is no gap between the film 34 and the film 34 where the light-shielding film does not exist. Therefore, it is possible to suppress the phenomenon that light enters the memory unit 16 through the gap. Further, since each groove 21 is formed so as to penetrate the second insulating film 31b, it is possible to suppress variations in white characteristics due to SiN break. Further, since the insulating film covering the side surface of the groove 21 of the present embodiment is the insulating film 22 formed by oxidation, the insulating film covering the side surface of the groove 21 can be easily thinned. Further, since the first insulating film 25 and the second insulating film 26 of the present embodiment do not need to be formed in the groove 21, the first insulating film 25 and the second insulating film 26 do not consider the size of the groove 21. It is possible to adjust the film thickness of.
　なお、本実施形態では、基板１１の表面Ｓ１に遮光膜３４を形成する前に、基板１１の表面Ｓ１側から基板１１内に溝２１を形成する。よって、溝２１内が熱リン酸水溶液などの薬液で処理される際に、遮光膜３４はまだ存在しないため、遮光膜３４が薬液にさらされることはない。これにより、遮光膜３４が薬液によりダメージを受けるという問題を回避することが可能となる。 In the present embodiment, the groove 21 is formed in the substrate 11 from the surface S1 side of the substrate 11 before the light-shielding film 34 is formed on the surface S1 of the substrate 11. Therefore, when the inside of the groove 21 is treated with a chemical solution such as a hot phosphoric acid aqueous solution, the light-shielding film 34 does not yet exist, so that the light-shielding film 34 is not exposed to the chemical solution. This makes it possible to avoid the problem that the light-shielding film 34 is damaged by the chemical solution.
　以上のように、本実施形態によれば、遮光膜２３と遮光膜３４との間に隙間が生じることを抑制することが可能となり、好適な遮光膜を形成することが可能となる。 As described above, according to the present embodiment, it is possible to suppress the formation of a gap between the light-shielding film 23 and the light-shielding film 34, and it is possible to form a suitable light-shielding film.
　図６から図１１は、第１実施形態の固体撮像装置の製造方法を示す断面図である。 6 to 11 are cross-sectional views showing a method of manufacturing the solid-state image sensor of the first embodiment.
　まず、基板１１を用意する（図６のＡ）。本実施形態では、図６のＢから図９のＡに示す工程が、基板１１の表面Ｓ１を上向きにし、基板１１の裏面Ｓ２を下向きにした状態で実行される。 First, prepare the board 11 (A in FIG. 6). In the present embodiment, the steps shown in FIGS. 6B to 9A are executed with the front surface S1 of the substrate 11 facing up and the back surface S2 of the substrate 11 facing down.
　次に、基板１１内に、各光電変換部１２のｐ＋型半導体領域１３、ｎ－型半導体領域１４、およびｐ型半導体領域１５と、各メモリ部１６のｐ＋型半導体領域１７、ｎ－型半導体領域１８、およびｐ型半導体領域１９と、その他の半導体領域２０と、複数の溝２１とを形成する（図６のＢ）。このようにして、基板１１内に、複数の光電変換部１２や複数のメモリ部１６が形成される。一方、各溝２１は、基板１１の表面Ｓ１側から基板１１内に形成され、互いに隣接する光電変換部１２とメモリ部１６との間に形成される。ただし、本実施形態の溝２１は、図６のＢの工程では、基板１１を貫通しないように形成される。 Next, in the substrate 11, the p + type semiconductor region 13, the n-type semiconductor region 14, and the p-type semiconductor region 15 of each photoelectric conversion unit 12, and the p + type semiconductor region 17, n-type semiconductor of each memory unit 16 A region 18, a p-type semiconductor region 19, another semiconductor region 20, and a plurality of grooves 21 are formed (B in FIG. 6). In this way, a plurality of photoelectric conversion units 12 and a plurality of memory units 16 are formed in the substrate 11. On the other hand, each groove 21 is formed in the substrate 11 from the surface S1 side of the substrate 11, and is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other. However, the groove 21 of the present embodiment is formed so as not to penetrate the substrate 11 in the step B of FIG.
　次に、基板１１の全面に絶縁膜５１を形成する（図７のＡ）。その結果、絶縁膜５１が、基板１１の表面Ｓ１や、基板１１の溝２１内に形成される。絶縁膜５１は例えば、窒化シリコン膜（ＳｉＮ膜）である。本実施形態の絶縁膜５１は、基板１１の結晶欠陥ダメージを回復するために形成される。 Next, the insulating film 51 is formed on the entire surface of the substrate 11 (A in FIG. 7). As a result, the insulating film 51 is formed in the surface S1 of the substrate 11 and in the groove 21 of the substrate 11. The insulating film 51 is, for example, a silicon nitride film (SiN film). The insulating film 51 of the present embodiment is formed to recover the crystal defect damage of the substrate 11.
　次に、熱リン酸水溶液などの薬液を用いて基板１１から絶縁膜５１を除去した後、基板１１の表面Ｓ１に絶縁層３１を形成する（図７のＢ）。絶縁層３１は、基板１１の表面Ｓ１に第１絶縁膜３１ａ、第２絶縁膜３１ｂ、および第３絶縁膜３１ｃを順に形成することで形成される（図３参照）。なお、本実施形態の絶縁層３１は溝２１内には形成されず、基板１１内および絶縁層３１内に溝２１が存在する構造が実現される。 Next, the insulating film 51 is removed from the substrate 11 using a chemical solution such as a hot phosphoric acid aqueous solution, and then the insulating layer 31 is formed on the surface S1 of the substrate 11 (B in FIG. 7). The insulating layer 31 is formed by forming the first insulating film 31a, the second insulating film 31b, and the third insulating film 31c in this order on the surface S1 of the substrate 11 (see FIG. 3). The insulating layer 31 of the present embodiment is not formed in the groove 21, and a structure in which the groove 21 exists in the substrate 11 and the insulating layer 31 is realized.
　次に、各溝２１内に、絶縁膜２２と遮光膜２３とを順に形成する（図８のＡ）。具体的には、各溝２１の側面および底面に絶縁膜２２が形成され、各溝２１内に絶縁膜２２を介して遮光膜２３が埋め込まれる。絶縁膜２２は例えば、各溝２１の側面および底面を酸化することで形成される。このようにして、遮光膜２３が、互いに隣接する光電変換部１２とメモリ部１６との間に形成される。 Next, the insulating film 22 and the light-shielding film 23 are sequentially formed in each groove 21 (A in FIG. 8). Specifically, an insulating film 22 is formed on the side surface and the bottom surface of each groove 21, and the light-shielding film 23 is embedded in each groove 21 via the insulating film 22. The insulating film 22 is formed, for example, by oxidizing the side surface and the bottom surface of each groove 21. In this way, the light-shielding film 23 is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other.
　次に、基板１１の表面Ｓ１に絶縁層３１を介して電極層３３を形成し、基板１１の表面Ｓ１に絶縁層３１および電極層３３を介して遮光膜３４を形成する（図８のＢ）。このようにして、基板１１の表面Ｓ１に、転送トランジスタＴＲＹやその他の画素トランジスタが形成される（図１６参照）。本実施形態の遮光膜３４は、電極層３３および遮光膜２３に接するように形成される。なお、本実施形態では、遮光膜２３が図８のＡに示す工程で形成され、遮光膜３４が図８のＢに示す工程で形成されているが、代わりに、遮光膜２３、３４が共に図８のＢに示す工程で電極層３３の形成後に形成されてもよい。 Next, the electrode layer 33 is formed on the surface S1 of the substrate 11 via the insulating layer 31, and the light-shielding film 34 is formed on the surface S1 of the substrate 11 via the insulating layer 31 and the electrode layer 33 (B in FIG. 8). .. In this way, the transfer transistor TRY and other pixel transistors are formed on the surface S1 of the substrate 11 (see FIG. 16). The light-shielding film 34 of the present embodiment is formed so as to be in contact with the electrode layer 33 and the light-shielding film 23. In the present embodiment, the light-shielding film 23 is formed by the step shown in FIG. 8A, and the light-shielding film 34 is formed by the step shown in FIG. 8B. Instead, both the light-shielding films 23 and 34 are formed. It may be formed after the electrode layer 33 is formed in the step shown in FIG. 8B.
　次に、基板１１の表面Ｓ１に、層間絶縁膜３２と、コンタクトプラグ３５と、配線層３６～３９と、ビアプラグ４０とを形成する（図９のＡ）。図９のＡに示す工程は例えば、基板１１の表面Ｓ１に、層間絶縁膜３２と配線層３６～３９とを交互に形成することで形成される。 Next, the interlayer insulating film 32, the contact plug 35, the wiring layers 36 to 39, and the via plug 40 are formed on the surface S1 of the substrate 11 (A in FIG. 9). The step shown in FIG. 9A is formed, for example, by alternately forming the interlayer insulating film 32 and the wiring layers 36 to 39 on the surface S1 of the substrate 11.
　次に、基板１１の上下を反転させる（図９のＢ）。その結果、基板１１の表面Ｓ１が下向きになり、基板１１の裏面Ｓ２が上向きになる。なお、上述の支持基板４１は例えば、図９のＢに示す工程を行う直前に、基板１１の表面Ｓ１に層間絶縁膜３２などを介して接着させてもよい。 Next, the substrate 11 is turned upside down (B in FIG. 9). As a result, the front surface S1 of the substrate 11 faces downward, and the back surface S2 of the substrate 11 faces upward. The above-mentioned support substrate 41 may be adhered to the surface S1 of the substrate 11 via an interlayer insulating film 32 or the like immediately before the step shown in FIG. 9B is performed.
　次に、基板１１を裏面Ｓ２から薄膜化する（図１０のＡ）。その結果、基板１１の裏面Ｓ２が溝２１まで低下し、溝２１の底面から絶縁膜２２が除去され、遮光膜２３が基板１１の裏面Ｓ２に露出する。このようにして、溝２１や遮光膜２３が、基板１１および絶縁層３１を貫通する形状に加工される。 Next, the substrate 11 is thinned from the back surface S2 (A in FIG. 10). As a result, the back surface S2 of the substrate 11 is lowered to the groove 21, the insulating film 22 is removed from the bottom surface of the groove 21, and the light-shielding film 23 is exposed on the back surface S2 of the substrate 11. In this way, the groove 21 and the light-shielding film 23 are processed into a shape that penetrates the substrate 11 and the insulating layer 31.
　次に、基板１１内に複数の溝２４を形成する（図１０のＢ）。図１０のＢは、これら複数の溝２４のうちの１つを示している。各溝２４は、基板１１の裏面Ｓ２側から基板１１内に形成され、互いに隣接する光電変換部１２とメモリ部１６との間に形成される。本実施形態の溝２４は、基板１１を貫通しないように形成される。 Next, a plurality of grooves 24 are formed in the substrate 11 (B in FIG. 10). B in FIG. 10 shows one of these plurality of grooves 24. Each groove 24 is formed in the substrate 11 from the back surface S2 side of the substrate 11, and is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other. The groove 24 of the present embodiment is formed so as not to penetrate the substrate 11.
　次に、基板１１の裏面Ｓ２や、基板１１の各溝２４内に、第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７を順に形成する（図１１のＡ）。具体的には、各溝２４の側面および底面に第１絶縁膜２５および第２絶縁膜２６が順に形成され、各溝２４内に第１絶縁膜２５および第２絶縁膜２６を介して遮光膜２７が埋め込まれる。これと同時に、第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７は、溝２４の外部で基板１１の裏面Ｓ２に順に積層される。このようにして、遮光膜２７が、互いに隣接する光電変換部１２とメモリ部１６との間に形成される。第１絶縁膜２５および第２絶縁膜２６は例えば、ＡＬＤにより形成される。 Next, the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are sequentially formed in the back surface S2 of the substrate 11 and in each groove 24 of the substrate 11 (A in FIG. 11). Specifically, the first insulating film 25 and the second insulating film 26 are sequentially formed on the side surface and the bottom surface of each groove 24, and a light-shielding film is formed in each groove 24 via the first insulating film 25 and the second insulating film 26. 27 is embedded. At the same time, the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are sequentially laminated on the back surface S2 of the substrate 11 outside the groove 24. In this way, the light-shielding film 27 is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other. The first insulating film 25 and the second insulating film 26 are formed by, for example, ALD.
　本実施形態では、第１絶縁膜２５と第２絶縁膜２６とを貫通する開口部を、エッチングにより遮光膜２３上に形成して、この開口部内に遮光膜２３を露出させた後に、第２絶縁膜２６上に遮光膜２７を形成する。その結果、遮光膜２７が、この開口部内で遮光膜２３に接するように形成される。なお、本実施形態では、基板１１内の遮光膜２７と基板１１外の遮光膜２７が同じ工程で形成されているが、代わりに、基板１１内の遮光膜２７を形成する工程を実行してから、その後に基板１１外の遮光膜２７を形成する工程を実行してもよい。 In the present embodiment, an opening penetrating the first insulating film 25 and the second insulating film 26 is formed on the light-shielding film 23 by etching, and the light-shielding film 23 is exposed in the opening, and then the second insulating film 23 is exposed. A light-shielding film 27 is formed on the insulating film 26. As a result, the light-shielding film 27 is formed so as to be in contact with the light-shielding film 23 within this opening. In the present embodiment, the light-shielding film 27 inside the substrate 11 and the light-shielding film 27 outside the substrate 11 are formed in the same step, but instead, the step of forming the light-shielding film 27 inside the substrate 11 is executed. Therefore, the step of forming the light-shielding film 27 outside the substrate 11 may be executed thereafter.
　次に、基板１１の裏面Ｓ２を覆うように、基板１１上に第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７を介して平坦化膜２８を形成する（図１０のＢ）。その結果、基板１１の裏面Ｓ２上に平坦な面が形成される。 Next, a flattening film 28 is formed on the substrate 11 via the first insulating film 25, the second insulating film 26, and the light-shielding film 27 so as to cover the back surface S2 of the substrate 11 (B in FIG. 10). As a result, a flat surface is formed on the back surface S2 of the substrate 11.
　その後、平坦化膜２８上に、図２に示すカラーフィルタ２９とオンチップレンズ３０とを順に形成する。このようにして、本実施形態の固体撮像装置が製造される。 After that, the color filter 29 and the on-chip lens 30 shown in FIG. 2 are sequentially formed on the flattening film 28. In this way, the solid-state image sensor of the present embodiment is manufactured.
　図１２から図１５は、第１実施形態の変形例の固体撮像装置の製造方法を示す断面図である。図１２から図１５については、図６から図１０との相違点を中心に説明し、図６から図１０との共通点の説明は適宜省略する。 12 to 15 are cross-sectional views showing a method of manufacturing a solid-state image sensor according to a modified example of the first embodiment. 12 to 15 will be described focusing on the differences from FIGS. 6 to 10, and the description of common points with FIGS. 6 to 10 will be omitted as appropriate.
　まず、基板１１を用意する（図１２のＡ）。次に、基板１１内に、各光電変換部１２のｐ＋型半導体領域１３、ｎ－型半導体領域１４、およびｐ型半導体領域１５と、各メモリ部１６のｐ＋型半導体領域１７、ｎ－型半導体領域１８、およびｐ型半導体領域１９と、その他の半導体領域２０と、各溝２１の第１部分２１ａとを形成する（図１２のＢ）。 First, prepare the substrate 11 (A in FIG. 12). Next, in the substrate 11, the p + type semiconductor region 13, the n-type semiconductor region 14, and the p-type semiconductor region 15 of each photoelectric conversion unit 12, and the p + type semiconductor region 17, n-type semiconductor of each memory unit 16 A region 18, a p-type semiconductor region 19, another semiconductor region 20, and a first portion 21a of each groove 21 are formed (B in FIG. 12).
　各溝２１の第１部分２１ａは、基板１１の表面Ｓ１側から基板１１内に形成され、互いに隣接する光電変換部１２とメモリ部１６との間に形成される。図１２のＢに示す各溝２１の第１部分２１ａは、図６のＢに示す各溝２１と同様に基板１１を貫通しないように形成されるが、図６のＢに示す各溝２１よりも浅く形成される。第１部分２１ａは例えば、基板１１の表面Ｓ１側から基板１１内にドライエッチングにより形成される。そのため、第１部分２１ａのＸ方向の幅は、基板１１の表面Ｓ１側から裏面Ｓ２側に進むにつれ狭くなっている。 The first portion 21a of each groove 21 is formed in the substrate 11 from the surface S1 side of the substrate 11 and is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other. The first portion 21a of each groove 21 shown in FIG. 12B is formed so as not to penetrate the substrate 11 like each groove 21 shown in FIG. 6B, but from each groove 21 shown in FIG. 6B. Is also shallowly formed. The first portion 21a is formed, for example, from the surface S1 side of the substrate 11 into the substrate 11 by dry etching. Therefore, the width of the first portion 21a in the X direction becomes narrower from the front surface S1 side to the back surface S2 side of the substrate 11.
　次に、図７のＡおよびＢに示す工程を実行し、基板１１の表面Ｓ１に絶縁層３１を形成した後、各溝２１の第１部分２１ａ内に、絶縁膜２２と遮光膜２３とを順に形成する（図１３のＡ）。さらに、基板１１の表面Ｓ１に絶縁層３１を介して電極層３３を形成し、基板１１の表面Ｓ１に絶縁層３１および電極層３３を介して遮光膜３４を形成する（図１３のＡ）。本変形例の遮光膜３４は、第１実施形態の遮光膜３４と同様に、電極層３３および遮光膜２３に接するように形成される。また、本変形例の遮光膜３４は、各溝２１の第１部分２１ａ内に形成されるため、遮光膜３４のＸ方向の幅が、基板１１の表面Ｓ１側から裏面Ｓ２側に進むにつれ狭くなっている。本変形例の遮光膜２３、３４はそれぞれ、本開示の第１および第２遮光膜の例である。次に、基板１１の表面Ｓ１に、層間絶縁膜３２と、コンタクトプラグ３５と、配線層３６～３９と、ビアプラグ４０とを形成した後、基板１１の上下を反転させる（図１３のＢ）。 Next, the steps shown in FIGS. 7A and 7B are executed to form the insulating layer 31 on the surface S1 of the substrate 11, and then the insulating film 22 and the light-shielding film 23 are formed in the first portion 21a of each groove 21. It is formed in order (A in FIG. 13). Further, the electrode layer 33 is formed on the surface S1 of the substrate 11 via the insulating layer 31, and the light-shielding film 34 is formed on the surface S1 of the substrate 11 via the insulating layer 31 and the electrode layer 33 (A in FIG. 13). The light-shielding film 34 of this modification is formed so as to be in contact with the electrode layer 33 and the light-shielding film 23, similarly to the light-shielding film 34 of the first embodiment. Further, since the light-shielding film 34 of this modification is formed in the first portion 21a of each groove 21, the width of the light-shielding film 34 in the X direction becomes narrower from the front surface S1 side to the back surface S2 side of the substrate 11. It has become. The light-shielding films 23 and 34 of this modification are examples of the first and second light-shielding films of the present disclosure, respectively. Next, after forming the interlayer insulating film 32, the contact plug 35, the wiring layers 36 to 39, and the via plug 40 on the surface S1 of the substrate 11, the substrate 11 is turned upside down (B in FIG. 13).
　次に、基板１１を裏面Ｓ２から薄膜化する（図１４のＡ）。その結果、基板１１の裏面Ｓ２がある程度低下するが、溝２１の第１部分２１ａまでは低下しない。次に、基板１１内に複数の溝２４と各溝２１の第２部分２１ｂとを形成する（図１４のＢ）。図１４のＢは、これら複数の溝２４のうちの１つを示している。 Next, the substrate 11 is thinned from the back surface S2 (A in FIG. 14). As a result, the back surface S2 of the substrate 11 is lowered to some extent, but the first portion 21a of the groove 21 is not lowered. Next, a plurality of grooves 24 and a second portion 21b of each groove 21 are formed in the substrate 11 (B in FIG. 14). B in FIG. 14 shows one of these plurality of grooves 24.
　各溝２４は、基板１１の裏面Ｓ２側から基板１１内に形成され、互いに隣接する光電変換部１２とメモリ部１６との間に形成される。本変形例の溝２４は、第１実施形態の溝２４と同様に、基板１１を貫通しないように形成される。溝２４は例えば、基板１１の裏面Ｓ２側から基板１１内にドライエッチングにより形成される。そのため、溝２４のＸ方向の幅は、基板１１の表面Ｓ１側から裏面Ｓ２側に進むにつれ広くなっている。 Each groove 24 is formed in the substrate 11 from the back surface S2 side of the substrate 11, and is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other. The groove 24 of this modification is formed so as not to penetrate the substrate 11 like the groove 24 of the first embodiment. The groove 24 is formed, for example, from the back surface S2 side of the substrate 11 into the substrate 11 by dry etching. Therefore, the width of the groove 24 in the X direction becomes wider from the front surface S1 side to the back surface S2 side of the substrate 11.
　各溝２１の第２部分２１ｂは、基板１１の裏面Ｓ２側から基板１１内に形成され、互いに隣接する光電変換部１２とメモリ部１６との間に形成される。本変形例の各溝２１の第２部分２１ｂは、対応する第１部分２１ａに達するように形成される。このようにして、各溝２１が、第１部分２１ａと第２部分２１ｂとを含み、基板１１内および絶縁層３１内を貫通する形状へと加工される。第２部分２１ｂは例えば、基板１１の裏面Ｓ２側から基板１１内にドライエッチングにより形成される。そのため、第２部分２１ｂのＸ方向の幅は、基板１１の表面Ｓ１側から裏面Ｓ２側に進むにつれ広くなっている。本変形例の溝２１は、第１実施形態の溝２１とおおむね同じ位置に形成されるが、本変形例の各溝２１の側面の形状は、第１実施形態の各溝２１の側面とは異なる形状を有している。 The second portion 21b of each groove 21 is formed in the substrate 11 from the back surface S2 side of the substrate 11, and is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other. The second portion 21b of each groove 21 of this modification is formed so as to reach the corresponding first portion 21a. In this way, each groove 21 includes the first portion 21a and the second portion 21b, and is processed into a shape that penetrates the inside of the substrate 11 and the inside of the insulating layer 31. The second portion 21b is formed, for example, from the back surface S2 side of the substrate 11 into the substrate 11 by dry etching. Therefore, the width of the second portion 21b in the X direction becomes wider from the front surface S1 side to the back surface S2 side of the substrate 11. The groove 21 of this modification is formed at substantially the same position as the groove 21 of the first embodiment, but the shape of the side surface of each groove 21 of this modification is different from the side surface of each groove 21 of the first embodiment. It has a different shape.
　なお、図１４Ｂに示す工程では、溝２４と溝２１の第２部分２１ｂとを同時に形成しても順番に形成してもよいが、同時に形成することが望ましい。溝２４と第２部分２１ｂとを同時に形成する場合には、溝２４の深さと第２部分２１ｂの深さが同じになるように、溝２１の第１部分２１ａの深さを設定することが望ましい。また、図１４Ｂに示す工程では、各溝２１の第１部分２１ａの底面から絶縁膜２２を除去しても除去しなくてもよい。 In the step shown in FIG. 14B, the groove 24 and the second portion 21b of the groove 21 may be formed at the same time or in order, but it is desirable that the grooves 24 and the second portion 21b are formed at the same time. When the groove 24 and the second portion 21b are formed at the same time, the depth of the first portion 21a of the groove 21 may be set so that the depth of the groove 24 and the depth of the second portion 21b are the same. desirable. Further, in the step shown in FIG. 14B, the insulating film 22 may or may not be removed from the bottom surface of the first portion 21a of each groove 21.
　次に、基板１１の裏面Ｓ２や、基板１１の各溝２４内や、基板１１の各溝２１の第２部分２１ｂ内に、第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７を順に形成する（図１５のＡ）。具体的には、各溝２４や各第２部分２１ｂの側面および底面に第１絶縁膜２５および第２絶縁膜２６が順に形成され、各溝２４内や各第２部分２１ｂ内に第１絶縁膜２５および第２絶縁膜２６を介して遮光膜２７が埋め込まれる。これと同時に、第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７は、溝２４の外部で基板１１の裏面Ｓ２に順に積層される。このようにして、遮光膜２７が、溝２４内または第２部分２１ｂ内で互いに隣接する光電変換部１２とメモリ部１６との間に形成される。本変形例の遮光膜２７は、各溝２４内や各第２部分２１ｂ内に形成されるため、基板１１内の遮光膜２７のＸ方向の幅が、各溝２４内でも各第２部分２１ｂ内でも、基板１１の表面Ｓ１側から裏面Ｓ２側に進むにつれ広くなっている。本変形例の遮光膜２７は、本開示の第３遮光膜の例である。 Next, the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are placed in the back surface S2 of the substrate 11, in each groove 24 of the substrate 11, and in the second portion 21b of each groove 21 of the substrate 11. It is formed in order (A in FIG. 15). Specifically, the first insulating film 25 and the second insulating film 26 are sequentially formed on the side surfaces and the bottom surface of each groove 24 and each second portion 21b, and the first insulation is formed in each groove 24 and each second portion 21b. The light-shielding film 27 is embedded via the film 25 and the second insulating film 26. At the same time, the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are sequentially laminated on the back surface S2 of the substrate 11 outside the groove 24. In this way, the light-shielding film 27 is formed between the photoelectric conversion unit 12 and the memory unit 16 adjacent to each other in the groove 24 or the second portion 21b. Since the light-shielding film 27 of this modification is formed in each groove 24 and in each second portion 21b, the width of the light-shielding film 27 in the substrate 11 in the X direction is widened in each groove 24 as well in each second portion 21b. Even inside, it becomes wider as it goes from the front surface S1 side of the substrate 11 to the back surface S2 side. The light-shielding film 27 of this modification is an example of the third light-shielding film of the present disclosure.
　本変形例では、第１絶縁膜２５と第２絶縁膜２６とを貫通する開口部を遮光膜２３上に形成せずに、第２絶縁膜２６上に遮光膜２７を形成する。その結果、遮光膜２７が、遮光膜２３に接しないように形成される。一方、第１絶縁膜２５と第２絶縁膜２６とを貫通する開口部を遮光膜２３上に形成してから、第２絶縁膜２６上に遮光膜２７を形成してもよい。この開口部は、第２部分２１ｂの底面に形成された第１絶縁膜２５と第２絶縁膜２６とを貫通するように形成される。すなわち、この開口部は、溝２１内に形成される。この場合、第２部分２１ｂの形成時か開口部の形成時に第１部分２１ｂの底面から絶縁膜２２を除去しておけば、遮光膜２７が、遮光膜２３に接するように形成される。 In this modification, the light-shielding film 27 is formed on the second insulating film 26 without forming the opening penetrating the first insulating film 25 and the second insulating film 26 on the light-shielding film 23. As a result, the light-shielding film 27 is formed so as not to come into contact with the light-shielding film 23. On the other hand, an opening penetrating the first insulating film 25 and the second insulating film 26 may be formed on the light-shielding film 23, and then the light-shielding film 27 may be formed on the second insulating film 26. This opening is formed so as to penetrate the first insulating film 25 and the second insulating film 26 formed on the bottom surface of the second portion 21b. That is, this opening is formed in the groove 21. In this case, if the insulating film 22 is removed from the bottom surface of the first portion 21b when the second portion 21b is formed or the opening is formed, the light-shielding film 27 is formed so as to be in contact with the light-shielding film 23.
　次に、基板１１上に第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７を介して平坦化膜２８を形成する（図１５のＢ）。その後、平坦化膜２８上に、図２に示すカラーフィルタ２９とオンチップレンズ３０とを順に形成する。このようにして、本変形例の固体撮像装置が製造される。 Next, the flattening film 28 is formed on the substrate 11 via the first insulating film 25, the second insulating film 26, and the light-shielding film 27 (B in FIG. 15). After that, the color filter 29 and the on-chip lens 30 shown in FIG. 2 are sequentially formed on the flattening film 28. In this way, the solid-state image sensor of this modification is manufactured.
　図１６は、第１実施形態の固体撮像装置の構造を示す平面図である。図１６は、図１の画素アレイ２内の４つの画素１の平面構造を模式的に示している。 FIG. 16 is a plan view showing the structure of the solid-state image sensor of the first embodiment. FIG. 16 schematically shows the planar structure of the four pixels 1 in the pixel array 2 of FIG.
　本実施形態では、各画素１内の光電変換部１２とメモリ部１６が、Ｘ方向に互いに隣接している。その結果、同じ画素１内の光電変換部１２とメモリ部１６だけでなく、異なる画素１内の光電変換部１２とメモリ部１６も、Ｘ方向に互いに隣接している。本実施形態の溝２１や溝２４は、同じ画素１内の光電変換部１２とメモリ部１６との間や、異なる画素１内の光電変換部１２とメモリ部１６との間に設けられている。これは、図２に示す溝２１や溝２４と同様である。図２は、図１６に示すＡ－Ａ’線に沿ったＸＺ断面を示している。 In the present embodiment, the photoelectric conversion unit 12 and the memory unit 16 in each pixel 1 are adjacent to each other in the X direction. As a result, not only the photoelectric conversion unit 12 and the memory unit 16 in the same pixel 1 but also the photoelectric conversion unit 12 and the memory unit 16 in different pixels 1 are adjacent to each other in the X direction. The groove 21 and the groove 24 of the present embodiment are provided between the photoelectric conversion unit 12 and the memory unit 16 in the same pixel 1 and between the photoelectric conversion unit 12 and the memory unit 16 in different pixels 1. .. This is the same as the groove 21 and the groove 24 shown in FIG. FIG. 2 shows an XZ cross section along the AA'line shown in FIG.
　図１６は、各画素１の転送トランジスタＴＲＧ、ＴＲＸ、ＴＲＧと、画素１間で共有されている転送トランジスタ（排出トランジスタ）ＯＦＧ、リセットトランジスタＲＳＴ、増幅トランジスタＡＭＰ、選択トランジスタＳＥＬ、およびダミートランジスタ（Ｄｕｍｍｙ）とを示している。これらの画素トランジスタは、基板１１の表面Ｓ１に設けられている。図１６はさらに、画素１間で共有されている浮遊拡散部ＦＤと別の拡散部ＯＦＤとを示している。これらの拡散部は、基板１１内の半導体領域２０内に設けられている。 FIG. 16 shows the transfer transistors TRG, TRX, and TRG of each pixel 1, the transfer transistor (emission transistor) OFG shared between the pixels 1, the reset transistor RST, the amplification transistor AMP, the selection transistor SEL, and the dummy transistor (Dummy). ) And. These pixel transistors are provided on the surface S1 of the substrate 11. FIG. 16 further shows a floating diffusion unit FD shared between pixels 1 and another diffusion unit OFD. These diffusion portions are provided in the semiconductor region 20 in the substrate 11.
　本実施形態の溝２１と溝２４は、図１６に示すように、Ｙ方向に延びる複数の直線上に配置されており、各直線上では、溝２１と溝２４が交互に配置されている。そのため、各直線上では、溝２１と溝２４が基板１１内で互いにつながっている。このような溝２１、２４の詳細について、図１７を参照して説明する。なお、図１６に示す溝２１、２４の配置は、図６から図１１に示す第１実施形態の固体撮像装置でも、図１２から図１５に示す第１実施形態の変形例の固体撮像装置でも共通である。 As shown in FIG. 16, the grooves 21 and the grooves 24 of the present embodiment are arranged on a plurality of straight lines extending in the Y direction, and the grooves 21 and the grooves 24 are alternately arranged on each straight line. Therefore, on each straight line, the groove 21 and the groove 24 are connected to each other in the substrate 11. Details of such grooves 21 and 24 will be described with reference to FIG. The arrangement of the grooves 21 and 24 shown in FIG. 16 may be the solid-state image sensor of the first embodiment shown in FIGS. 6 to 11 or the solid-state image sensor of the modified example of the first embodiment shown in FIGS. 12 to 15. It is common.
　図１７は、第１実施形態の固体撮像装置の構造（図１７のＡ）と、第１実施形態の変形例の固体撮像装置の構造（図１７のＢ）とを示す断面図である。図１７のＡおよびＢは、図１６に示すＢ－Ｂ’線に沿ったＹＺ断面を示している。 FIG. 17 is a cross-sectional view showing the structure of the solid-state image sensor of the first embodiment (A in FIG. 17) and the structure of the solid-state image sensor of the modified example of the first embodiment (B in FIG. 17). 17A and B show a YZ cross section along the BB'line shown in FIG.
　図１７のＡでは、溝２１が基板１１および絶縁層３１を貫通しており、各溝２１内に絶縁膜２２および遮光膜２３が形成されている。また、図１７のＡでは、溝２４が基板１１を貫通しておらず、各溝２４内に第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７が形成されている。 In A of FIG. 17, the groove 21 penetrates the substrate 11 and the insulating layer 31, and the insulating film 22 and the light-shielding film 23 are formed in each groove 21. Further, in A of FIG. 17, the groove 24 does not penetrate the substrate 11, and the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are formed in each groove 24.
　図１７のＡに示す溝２１と溝２４とは、基板１１内で互いにつながっている。ただし、溝２１内の遮光膜２３と、溝２４内の遮光膜２７との間には、絶縁膜２２、第１絶縁膜２５、および第２絶縁膜２６が介在している。本実施形態の遮光膜２３は、溝２４内の遮光膜２７ではなく、溝２４外の遮光膜２７と接している（図２参照）。 The groove 21 and the groove 24 shown in A of FIG. 17 are connected to each other in the substrate 11. However, the insulating film 22, the first insulating film 25, and the second insulating film 26 are interposed between the light-shielding film 23 in the groove 21 and the light-shielding film 27 in the groove 24. The light-shielding film 23 of the present embodiment is in contact with the light-shielding film 27 outside the groove 24, not with the light-shielding film 27 inside the groove 24 (see FIG. 2).
　図１７のＢでは、溝２１が、基板１１および絶縁層３１を貫通しているが、絶縁膜２２および遮光膜２３を含む領域だけでなく、第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７を含む領域も含んでいる。前者の領域は第１部分２１ａであり、後者の領域は第２部分２１ｂである。図１７のＢは、後者の領域（第２部分２１ｂ）を破線で示している。また、図１７のＢでは、溝２４が基板１１を貫通しておらず、各溝２４内に第１絶縁膜２５、第２絶縁膜２６、および遮光膜２７が形成されている。 In FIG. 17B, the groove 21 penetrates the substrate 11 and the insulating layer 31, but not only the region including the insulating film 22 and the light-shielding film 23, but also the first insulating film 25, the second insulating film 26, and the insulating film 26. It also includes a region including the light-shielding film 27. The former region is the first portion 21a and the latter region is the second portion 21b. In FIG. 17, B shows the latter region (second portion 21b) with a broken line. Further, in B of FIG. 17, the groove 24 does not penetrate the substrate 11, and the first insulating film 25, the second insulating film 26, and the light-shielding film 27 are formed in each groove 24.
　図１７のＢに示す溝２１と溝２４とは、基板１１内において、破線で示す箇所で互いにつながっている。ただし、溝２１の第１部分２１ａ内の遮光膜２３と、溝２１の第２部分２１ｂ内および溝２４内の遮光膜２７との間には、絶縁膜２２、第１絶縁膜２５、および第２絶縁膜２６が介在している。一方、溝２１の第２部分２１ｂ内の遮光膜２７と、溝２４内の遮光膜２７との間には、絶縁膜２２、第１絶縁膜２５、および第２絶縁膜２６は介在していない。 The groove 21 and the groove 24 shown in FIG. 17B are connected to each other at the points indicated by the broken lines in the substrate 11. However, the insulating film 22, the first insulating film 25, and the first insulating film 25 are between the light-shielding film 23 in the first portion 21a of the groove 21 and the light-shielding film 27 in the second portion 21b of the groove 21 and in the groove 24. 2 Insulating film 26 is interposed. On the other hand, the insulating film 22, the first insulating film 25, and the second insulating film 26 are not interposed between the light-shielding film 27 in the second portion 21b of the groove 21 and the light-shielding film 27 in the groove 24. ..
　図１７のＡに示す構造には、溝２１を第１部分２１ａと第２部分２１ｂとに分けて形成する必要がなく、溝２１を容易に形成できるという利点がある。しかしながら、図１７のＡに示す構造では一般に、溝２１のＹ方向の位置と、溝２４のＹ方向の位置とを、高精度に位置合わせすることが求められる。一方、図１７のＢに示す構造には、このような位置合わせが不要になるという利点がある。 The structure shown in A of FIG. 17 has an advantage that the groove 21 does not need to be formed separately from the first portion 21a and the second portion 21b, and the groove 21 can be easily formed. However, in the structure shown in FIG. 17A, it is generally required to align the position of the groove 21 in the Y direction with the position of the groove 24 in the Y direction with high accuracy. On the other hand, the structure shown in FIG. 17B has an advantage that such alignment is not required.
　以上のように、本実施形態やその変形例では、基板１１内の遮光膜２１と、基板１１の表面Ｓ１の遮光膜３４とを、互いに接するように形成する。よって、本実施形態やその変形例によれば、遮光膜２３と遮光膜３４との間に隙間が生じることを抑制することが可能となるなど、好適な遮光膜を形成することが可能となる。 As described above, in the present embodiment and its modification, the light-shielding film 21 in the substrate 11 and the light-shielding film 34 on the surface S1 of the substrate 11 are formed so as to be in contact with each other. Therefore, according to the present embodiment and its modifications, it is possible to form a suitable light-shielding film, such as suppressing the formation of a gap between the light-shielding film 23 and the light-shielding film 34. ..
　（応用例）
　図１８は、電子機器の構成例を示すブロック図である。図１８に示す電気機器は、カメラ１００である。 (Application example)
FIG. 18 is a block diagram showing a configuration example of an electronic device. The electrical device shown in FIG. 18 is a camera 100.
　カメラ１００は、レンズ群などを含む光学部１０１と、第１実施形態の固体撮像装置である撮像装置１０２と、カメラ信号処理回路であるＤＳＰ（Digital Signal Processor）回路１０３と、フレームメモリ１０４と、表示部１０５と、記録部１０６と、操作部１０７と、電源部１０８とを備えている。また、ＤＳＰ回路１０３、フレームメモリ１０４、表示部１０５、記録部１０６、操作部１０７、および電源部１０８は、バスライン１０９を介して相互に接続されている。 The camera 100 includes an optical unit 101 including a lens group and the like, an image pickup device 102 which is a solid-state image pickup device of the first embodiment, a DSP (Digital Signal Processor) circuit 103 which is a camera signal processing circuit, a frame memory 104, and the like. It includes a display unit 105, a recording unit 106, an operation unit 107, and a power supply unit 108. Further, the DSP circuit 103, the frame memory 104, the display unit 105, the recording unit 106, the operation unit 107, and the power supply unit 108 are connected to each other via the bus line 109.
　光学部１０１は、被写体からの入射光（像光）を取り込んで、撮像装置１０２の撮像面上に結像する。撮像装置１０２は、光学部１０１により撮像面上に結像された入射光の光量を画素単位で電気信号に変換して、画素信号として出力する。 The optical unit 101 takes in incident light (image light) from the subject and forms an image on the image pickup surface of the image pickup device 102. The image pickup apparatus 102 converts the amount of incident light imaged on the image pickup surface by the optical unit 101 into an electric signal in pixel units, and outputs the light amount as a pixel signal.
　ＤＳＰ回路１０３は、撮像装置１０２により出力された画素信号について信号処理を行う。フレームメモリ１０４は、撮像装置１０２で撮像された動画または静止画の１画面を記憶しておくためのメモリである。 The DSP circuit 103 performs signal processing on the pixel signal output by the image pickup device 102. The frame memory 104 is a memory for storing one screen of a moving image or a still image captured by the image pickup apparatus 102.
　表示部１０５は、例えば液晶パネルや有機ＥＬパネルなどのパネル型表示装置を含んでおり、撮像装置１０２で撮像された動画または静止画を表示する。記録部１０６は、撮像装置１０２で撮像された動画または静止画を、ハードディスクや半導体メモリなどの記録媒体に記録する。 The display unit 105 includes a panel-type display device such as a liquid crystal panel or an organic EL panel, and displays a moving image or a still image captured by the image pickup device 102. The recording unit 106 records a moving image or a still image captured by the image pickup apparatus 102 on a recording medium such as a hard disk or a semiconductor memory.
　操作部１０７は、ユーザによる操作の下に、カメラ１００が持つ様々な機能について操作指令を発する。電源部１０８は、ＤＳＰ回路１０３、フレームメモリ１０４、表示部１０５、記録部１０６、および操作部１０７の動作電源となる各種の電源を、これらの供給対象に対して適宜供給する。 The operation unit 107 issues operation commands for various functions of the camera 100 under the operation of the user. The power supply unit 108 appropriately supplies various power sources that serve as operating power sources for the DSP circuit 103, the frame memory 104, the display unit 105, the recording unit 106, and the operation unit 107 to these supply targets.
　撮像装置１０２として、第１実施形態の固体撮像装置を使用することで、良好な画像の取得が期待できる。 By using the solid-state image sensor of the first embodiment as the image sensor 102, good image acquisition can be expected.
　当該固体撮像装置は、その他の様々な製品に応用することができる。例えば、当該固体撮像装置は、自動車、電気自動車、ハイブリッド電気自動車、自動二輪車、自転車、パーソナルモビリティ、飛行機、ドローン、船舶、ロボットなどの種々の移動体に搭載されてもよい。 The solid-state image sensor can be applied to various other products. For example, the solid-state imaging device may be mounted on various moving objects such as automobiles, electric vehicles, hybrid electric vehicles, motorcycles, bicycles, personal mobility, airplanes, drones, ships, and robots.
　図１９は、移動体制御システムの構成例を示すブロック図である。図１９に示す移動体制御システムは、車両制御システム２００である。 FIG. 19 is a block diagram showing a configuration example of a mobile control system. The mobile control system shown in FIG. 19 is a vehicle control system 200.
　車両制御システム２００は、通信ネットワーク２０１を介して接続された複数の電子制御ユニットを備える。図１９に示した例では、車両制御システム２００は、駆動系制御ユニット２１０と、ボディ系制御ユニット２２０と、車外情報検出ユニット２３０と、車内情報検出ユニット２４０と、統合制御ユニット２５０とを備えている。図１９はさらに、統合制御ユニット２５０の構成部として、マイクロコンピュータ２５１と、音声画像出力部２５２と、車載ネットワークＩ／Ｆ（Interface）２５３とを示している。 The vehicle control system 200 includes a plurality of electronic control units connected via the communication network 201. In the example shown in FIG. 19, the vehicle control system 200 includes a drive system control unit 210, a body system control unit 220, an outside information detection unit 230, an in-vehicle information detection unit 240, and an integrated control unit 250. There is. FIG. 19 further shows a microcomputer 251, an audio image output unit 252, and an in-vehicle network I / F (Interface) 253 as components of the integrated control unit 250.
　駆動系制御ユニット２１０は、各種プログラムに従って、車両の駆動系に関連する装置の動作を制御する。例えば、駆動系制御ユニット２１０は、内燃機関や駆動用モータなどの車両の駆動力を発生させるための駆動力発生装置や、駆動力を車輪に伝達するための駆動力伝達機構や、車両の舵角を調節するステアリング機構や、車両の制動力を発生させる制動装置などの制御装置として機能する。 The drive system control unit 210 controls the operation of the device related to the drive system of the vehicle according to various programs. For example, the drive system control unit 210 includes a driving force generator for generating a driving force of a vehicle such as an internal combustion engine and a driving motor, a driving force transmission mechanism for transmitting the driving force to wheels, and a steering wheel of the vehicle. It functions as a control device such as a steering mechanism that adjusts the angle and a braking device that generates braking force for the vehicle.
　ボディ系制御ユニット２２０は、各種プログラムに従って、車体に装備された各種装置の動作を制御する。例えば、ボディ系制御ユニット２２０は、スマートキーシステム、キーレスエントリシステム、パワーウィンドウ装置、各種ランプ（例えば、ヘッドランプ、バックランプ、ブレーキランプ、ウィンカー、フォグランプ）などの制御装置として機能する。この場合、ボディ系制御ユニット２２０には、鍵を代替する携帯機から発信される電波または各種スイッチの信号が入力され得る。ボディ系制御ユニット２２０は、このような電波または信号の入力を受け付け、車両のドアロック装置、パワーウィンドウ装置、ランプなどを制御する。 The body system control unit 220 controls the operation of various devices mounted on the vehicle body according to various programs. For example, the body system control unit 220 functions as a control device such as a smart key system, a keyless entry system, a power window device, and various lamps (for example, a headlamp, a back lamp, a brake lamp, a winker, and a fog lamp). In this case, a radio wave transmitted from a portable device that substitutes for a key or a signal of various switches may be input to the body system control unit 220. The body system control unit 220 receives such radio wave or signal input and controls a vehicle door lock device, a power window device, a lamp, and the like.
　車外情報検出ユニット２３０は、車両制御システム２００を搭載した車両の外部の情報を検出する。車外情報検出ユニット２３０には、例えば撮像部２３１が接続される。車外情報検出ユニット２３０は、撮像部２３１に車外の画像を撮像させると共に、撮像された画像を撮像部２３１から受信する。車外情報検出ユニット２３０は、受信した画像に基づいて、人、車、障害物、標識、路面上の文字などの物体検出処理または距離検出処理を行ってもよい。 The outside information detection unit 230 detects information outside the vehicle equipped with the vehicle control system 200. For example, an image pickup unit 231 is connected to the vehicle outside information detection unit 230. The vehicle outside information detection unit 230 causes the image pickup unit 231 to capture an image of the outside of the vehicle, and receives the captured image from the image pickup unit 231. The vehicle outside information detection unit 230 may perform object detection processing or distance detection processing such as a person, a vehicle, an obstacle, a sign, or a character on a road surface based on the received image.
　撮像部２３１は、光を受光し、その光の受光量に応じた電気信号を出力する光センサである。撮像部２３１は、電気信号を画像として出力することもできるし、測距の情報として出力することもできる。撮像部２３１が受光する光は、可視光であってもよいし、赤外線などの非可視光であってもよい。撮像部２３１は、第１実施形態の固体撮像装置を含んでいる。 The image pickup unit 231 is an optical sensor that receives light and outputs an electric signal according to the amount of the light received. The image pickup unit 231 can output an electric signal as an image or can output it as distance measurement information. The light received by the image pickup unit 231 may be visible light or invisible light such as infrared light. The image pickup unit 231 includes the solid-state image pickup device of the first embodiment.
　車内情報検出ユニット２４０は、車両制御システム２００を搭載した車両の内部の情報を検出する。車内情報検出ユニット２４０には例えば、運転者の状態を検出する運転者状態検出部２４１が接続される。例えば、運転者状態検出部２４１は、運転者を撮像するカメラを含み、車内情報検出ユニット２４０は、運転者状態検出部２４１から入力される検出情報に基づいて、運転者の疲労度合いまたは集中度合いを算出してもよいし、運転者が居眠りをしていないかを判別してもよい。このカメラは、第１実施形態の固体撮像装置を含んでいてもよく、例えば、図１８に示すカメラ１００でもよい。 The in-vehicle information detection unit 240 detects information inside the vehicle equipped with the vehicle control system 200. For example, a driver state detection unit 241 that detects the state of the driver is connected to the in-vehicle information detection unit 240. For example, the driver state detection unit 241 includes a camera that images the driver, and the in-vehicle information detection unit 240 has a degree of fatigue or concentration of the driver based on the detection information input from the driver state detection unit 241. May be calculated, or it may be determined whether or not the driver has fallen asleep. This camera may include the solid-state image sensor of the first embodiment, and may be, for example, the camera 100 shown in FIG.
　マイクロコンピュータ２５１は、車外情報検出ユニット２３０または車内情報検出ユニット２４０で取得される車内外の情報に基づいて、駆動力発生装置、ステアリング機構、または制動装置の制御目標値を演算し、駆動系制御ユニット２１０に対して制御指令を出力することができる。例えば、マイクロコンピュータ２５１は、車両の衝突回避、衝撃緩和、車間距離に基づく追従走行、車速維持走行、衝突警告、レーン逸脱警告などのＡＤＡＳ（Advanced Driver Assistance System）の機能実現を目的とした協調制御を行うことができる。 The microcomputer 251 calculates a control target value of the driving force generator, the steering mechanism, or the braking device based on the information inside and outside the vehicle acquired by the information detection unit 230 outside the vehicle or the information inside the vehicle 240, and controls the drive system. A control command can be output to the unit 210. For example, the microcomputer 251 is a coordinated control for the purpose of realizing ADAS (Advanced Driver Assistance System) functions such as vehicle collision avoidance, impact mitigation, follow-up driving based on inter-vehicle distance, vehicle speed maintenance driving, collision warning, and lane deviation warning. It can be performed.
　また、マイクロコンピュータ２５１は、車外情報検出ユニット２３０または車内情報検出ユニット２４０で取得される車両の周囲の情報に基づいて駆動力発生装置、ステアリング機構、または制動装置を制御することにより、運転者の操作によらずに自律的に走行する自動運転などを目的とした協調制御を行うことができる。 Further, the microcomputer 251 controls the driving force generator, the steering mechanism, or the braking device based on the information around the vehicle acquired by the vehicle exterior information detection unit 230 or the vehicle interior information detection unit 240, thereby controlling the driver. It is possible to perform coordinated control for the purpose of automatic driving that runs autonomously without depending on the operation.
　また、マイクロコンピュータ２５１は、車外情報検出ユニット２３０で取得される車外の情報に基づいて、ボディ系制御ユニット２２０に対して制御指令を出力することができる。例えば、マイクロコンピュータ２５１は、車外情報検出ユニット２３０で検知した先行車または対向車の位置に応じてヘッドランプを制御し、ハイビームをロービームに切り替えるなどの防眩を図ることを目的とした協調制御を行うことができる。 Further, the microcomputer 251 can output a control command to the body system control unit 220 based on the information outside the vehicle acquired by the vehicle outside information detection unit 230. For example, the microcomputer 251 controls the headlamps according to the position of the preceding vehicle or the oncoming vehicle detected by the outside information detection unit 230, and performs cooperative control for the purpose of anti-glare such as switching the high beam to the low beam. It can be carried out.
　音声画像出力部２５２は、車両の搭乗者または車外に対して視覚的または聴覚的に情報を通知することが可能な出力装置に、音声および画像のうちの少なくとも一方の出力信号を送信する。図１９の例では、このような出力装置として、オーディオスピーカ２６１、表示部２６２、およびインストルメントパネル２６３が示されている。表示部２６２は例えば、オンボードディスプレイまたはヘッドアップディスプレイを含んでいてもよい。 The audio image output unit 252 transmits an output signal of at least one of audio and image to an output device capable of visually or audibly notifying the passenger of the vehicle or the outside of the vehicle. In the example of FIG. 19, an audio speaker 261, a display unit 262, and an instrument panel 263 are shown as such an output device. The display unit 262 may include, for example, an onboard display or a head-up display.
　図２０は、図１９の撮像部２３１の設定位置の具体例を示す平面図である。 FIG. 20 is a plan view showing a specific example of the set position of the image pickup unit 231 of FIG.
　図２０に示す車両３００は、撮像部２３１として、撮像部３０１、３０２、３０３、３０４、３０５を備えている。撮像部３０１、３０２、３０３、３０４、３０５は例えば、車両３００のフロントノーズ、サイドミラー、リアバンパ、バックドア、車室内のフロントガラスの上部などの位置に設けられる。 The vehicle 300 shown in FIG. 20 includes image pickup units 301, 302, 303, 304, and 305 as image pickup units 231. The image pickup units 301, 302, 303, 304, and 305 are provided, for example, at positions such as the front nose, side mirrors, rear bumpers, back doors, and the upper part of the windshield in the vehicle interior of the vehicle 300.
　フロントノーズに備えられる撮像部３０１は、主として車両３００の前方の画像を取得する。左のサイドミラーに備えられる撮像部３０２と、右のサイドミラーに備えられる撮像部３０３は、主として車両３００の側方の画像を取得する。リアバンパまたはバックドアに備えられる撮像部３０４は、主として車両３００の後方の画像を取得する。車室内のフロントガラスの上部に備えられる撮像部３０５は、主として車両３００の前方の画像を取得する。撮像部３０５は例えば、先行車両、歩行者、障害物、信号機、交通標識、車線などの検出に用いられる。 The image pickup unit 301 provided in the front nose mainly acquires an image in front of the vehicle 300. The image pickup unit 302 provided in the left side mirror and the image pickup section 303 provided in the right side mirror mainly acquire an image of the side of the vehicle 300. The image pickup unit 304 provided on the rear bumper or the back door mainly acquires an image of the rear of the vehicle 300. The image pickup unit 305 provided on the upper part of the windshield in the vehicle interior mainly acquires an image in front of the vehicle 300. The image pickup unit 305 is used, for example, to detect a preceding vehicle, a pedestrian, an obstacle, a traffic light, a traffic sign, a lane, or the like.
　図２０は、撮像部３０１、３０２、３０３、３０４（以下「撮像部３０１～３０４」と表記する）の撮像範囲の例を示している。撮像範囲３１１は、フロントノーズに設けられた撮像部３０１の撮像範囲を示す。撮像範囲３１２は、左のサイドミラーに設けられた撮像部３０２の撮像範囲を示す。撮像範囲３１３は、右のサイドミラーに設けられた撮像部３０３の撮像範囲を示す。撮像範囲３１４は、リアバンパまたはバックドアに設けられた撮像部３０４の撮像範囲を示す。例えば、撮像部３０１～３０４で撮像された画像データが重ね合わせられることにより、車両３００を上方から見た俯瞰画像が得られる。以下、撮像範囲３１１、３１２、３１３、３１４を「撮像範囲３１１～３１４」と表記する。 FIG. 20 shows an example of the imaging range of the imaging units 301, 302, 303, 304 (hereinafter referred to as “imaging unit 301 to 304”). The imaging range 311 indicates the imaging range of the imaging unit 301 provided on the front nose. The image pickup range 312 indicates the image pickup range of the image pickup unit 302 provided on the left side mirror. The image pickup range 313 indicates the image pickup range of the image pickup unit 303 provided on the right side mirror. The image pickup range 314 indicates the image pickup range of the image pickup unit 304 provided on the rear bumper or the back door. For example, by superimposing the image data captured by the image pickup units 301 to 304, a bird's-eye view image of the vehicle 300 viewed from above can be obtained. Hereinafter, the imaging range 311, 312, 313, 314 will be referred to as "imaging range 311 to 314".
　撮像部３０１～３０４の少なくとも１つは、距離情報を取得する機能を有していてもよい。例えば、撮像部３０１～３０４の少なくとも１つは、複数の撮像装置を含むステレオカメラであってもよいし、位相差検出用の画素を有する撮像装置であってもよい。 At least one of the image pickup units 301 to 304 may have a function of acquiring distance information. For example, at least one of the image pickup units 301 to 304 may be a stereo camera including a plurality of image pickup devices, or may be an image pickup device having pixels for phase difference detection.
　例えば、マイクロコンピュータ２５１（図１９）は、撮像部３０１～３０４から得られた距離情報を基に、撮像範囲３１１～３１４内における各立体物までの距離と、この距離の時間的変化（車両３００に対する相対速度）を算出する。マイクロコンピュータ２５１は、これらの算出結果に基づいて、車両３００の進行路上にある最も近い立体物で、車両３００とほぼ同じ方向に所定の速度（例えば、０ｋｍ／ｈ以上）で走行する立体物を、先行車として抽出することができる。さらに、マイクロコンピュータ２５１は、先行車の手前にあらかじめ確保すべき車間距離を設定し、自動ブレーキ制御（追従停止制御も含む）や自動加速制御（追従発進制御も含む）等を行うことができる。このように、この例によれば、運転者の操作によらずに自律的に走行する自動運転等を目的とした協調制御を行うことができる。 For example, the microcomputer 251 (FIG. 19) is based on the distance information obtained from the imaging units 301 to 304, the distance to each three-dimensional object within the imaging range 311 to 314, and the temporal change of this distance (vehicle 300). Relative velocity to) is calculated. Based on these calculation results, the microcomputer 251 is the closest three-dimensional object on the traveling path of the vehicle 300, and is a three-dimensional object traveling at a predetermined speed (for example, 0 km / h or more) in almost the same direction as the vehicle 300. , Can be extracted as a preceding vehicle. Further, the microcomputer 251 can set an inter-vehicle distance to be secured in front of the preceding vehicle in advance, and can perform automatic brake control (including follow-up stop control), automatic acceleration control (including follow-up start control), and the like. As described above, according to this example, it is possible to perform coordinated control for the purpose of automatic driving or the like that autonomously travels without the operation of the driver.
　例えば、マイクロコンピュータ２５１は、撮像部３０１～３０４から得られた距離情報を基に、立体物に関する立体物データを、２輪車、普通車両、大型車両、歩行者、電柱その他の立体物に分類して抽出し、障害物の自動回避に用いることができる。例えば、マイクロコンピュータ２５１は、車両３００の周辺の障害物を、車両３００のドライバが視認可能な障害物と、視認困難な障害物とに識別する。そして、マイクロコンピュータ２５１は、各障害物との衝突の危険度を示す衝突リスクを判断し、衝突リスクが設定値以上で衝突可能性がある状況であるときには、オーディオスピーカ２６１や表示部２６２を介してドライバに警報を出力することや、駆動系制御ユニット２１０を介して強制減速や回避操舵を行うことで、衝突回避のための運転支援を行うことができる。 For example, the microcomputer 251 classifies three-dimensional object data related to a three-dimensional object into two-wheeled vehicles, ordinary vehicles, large vehicles, pedestrians, electric poles, and other three-dimensional objects based on the distance information obtained from the imaging units 301 to 304. It can be extracted and used for automatic avoidance of obstacles. For example, the microcomputer 251 distinguishes obstacles around the vehicle 300 into obstacles that can be seen by the driver of the vehicle 300 and obstacles that are difficult to see. Then, the microcomputer 251 determines the collision risk indicating the risk of collision with each obstacle, and when the collision risk is equal to or higher than the set value and there is a possibility of collision, the microcomputer 251 is used via the audio speaker 261 or the display unit 262. By outputting an alarm to the driver and performing forced deceleration and avoidance steering via the drive system control unit 210, driving support for collision avoidance can be provided.
　撮像部３０１～３０４の少なくとも１つは、赤外線を検出する赤外線カメラであってもよい。例えば、マイクロコンピュータ２５１は、撮像部３０１～３０４の撮像画像中に歩行者が存在するか否かを判定することで、歩行者を認識することができる。かかる歩行者の認識は例えば、赤外線カメラとしての撮像部３０１～３０４の撮像画像における特徴点を抽出する手順と、物体の輪郭を示す一連の特徴点にパターンマッチング処理を行って歩行者か否かを判別する手順により行われる。マイクロコンピュータ２５１が、撮像部３０１～３０４の撮像画像中に歩行者が存在すると判定し、歩行者を認識すると、音声画像出力部２５２は、当該認識された歩行者に強調のための方形輪郭線を重畳表示するように、表示部２６２を制御する。また、音声画像出力部２５２は、歩行者を示すアイコン等を所望の位置に表示するように表示部２６２を制御してもよい。 At least one of the image pickup units 301 to 304 may be an infrared camera that detects infrared rays. For example, the microcomputer 251 can recognize a pedestrian by determining whether or not a pedestrian is present in the captured images of the imaging units 301 to 304. Such recognition of a pedestrian is, for example, whether or not the pedestrian is a pedestrian by performing a procedure for extracting feature points in the captured images of the image pickup units 301 to 304 as an infrared camera and a pattern matching process on a series of feature points showing the outline of the object. It is performed by the procedure for determining. When the microcomputer 251 determines that a pedestrian is present in the captured images of the imaging units 301 to 304 and recognizes the pedestrian, the audio image output unit 252 has a square contour line for emphasizing the recognized pedestrian. The display unit 262 is controlled so as to superimpose and display. Further, the audio image output unit 252 may control the display unit 262 so as to display an icon or the like indicating a pedestrian at a desired position.
　図２１は、本開示に係る技術（本技術）が適用され得る内視鏡手術システムの概略的な構成の一例を示す図である。 FIG. 21 is a diagram showing an example of a schematic configuration of an endoscopic surgery system to which the technique according to the present disclosure (the present technique) can be applied.
　図２１では、術者（医師）５３１が、内視鏡手術システム４００を用いて、患者ベッド５３３上の患者５３２に手術を行っている様子が図示されている。図示するように、内視鏡手術システム４００は、内視鏡５００と、気腹チューブ５１１やエネルギー処置具５１２等の、その他の術具５１０と、内視鏡５００を支持する支持アーム装置５２０と、内視鏡下手術のための各種の装置が搭載されたカート６００と、から構成される。 FIG. 21 illustrates how the surgeon (doctor) 531 is performing surgery on patient 532 on patient bed 533 using the endoscopic surgery system 400. As shown, the endoscopic surgery system 400 includes an endoscope 500, other surgical tools 510 such as an abdominal tube 511 and an energy treatment tool 512, and a support arm device 520 that supports the endoscope 500. , A cart 600 equipped with various devices for endoscopic surgery.
　内視鏡５００は、先端から所定の長さの領域が患者５３２の体腔内に挿入される鏡筒５０１と、鏡筒５０１の基端に接続されるカメラヘッド５０２と、から構成される。図示する例では、硬性の鏡筒５０１を有するいわゆる硬性鏡として構成される内視鏡５００を図示しているが、内視鏡５００は、軟性の鏡筒を有するいわゆる軟性鏡として構成されてもよい。 The endoscope 500 is composed of a lens barrel 501 in which a region having a predetermined length from the tip is inserted into the body cavity of the patient 532, and a camera head 502 connected to the base end of the lens barrel 501. In the illustrated example, the endoscope 500 configured as a so-called rigid mirror having a rigid lens barrel 501 is shown, but the endoscope 500 may be configured as a so-called flexible mirror having a flexible lens barrel. good.
　鏡筒５０１の先端には、対物レンズが嵌め込まれた開口部が設けられている。内視鏡５００には光源装置６０３が接続されており、当該光源装置６０３によって生成された光が、鏡筒５０１の内部に延設されるライトガイドによって当該鏡筒の先端まで導光され、対物レンズを介して患者５３２の体腔内の観察対象に向かって照射される。なお、内視鏡５００は、直視鏡であってもよいし、斜視鏡又は側視鏡であってもよい。 An opening in which an objective lens is fitted is provided at the tip of the lens barrel 501. A light source device 603 is connected to the endoscope 500, and the light generated by the light source device 603 is guided to the tip of the lens barrel by a light guide extending inside the lens barrel 501, and is an objective. It is irradiated toward the observation target in the body cavity of the patient 532 through the lens. The endoscope 500 may be a direct endoscope, a perspective mirror, or a side endoscope.
　カメラヘッド５０２の内部には光学系及び撮像素子が設けられており、観察対象からの反射光（観察光）は当該光学系によって当該撮像素子に集光される。当該撮像素子によって観察光が光電変換され、観察光に対応する電気信号、すなわち観察像に対応する画像信号が生成される。当該画像信号は、ＲＡＷデータとしてカメラコントロールユニット（ＣＣＵ：　Ｃａｍｅｒａ　Ｃｏｎｔｒｏｌ　Ｕｎｉｔ）６０１に送信される。 An optical system and an image sensor are provided inside the camera head 502, and the reflected light (observation light) from the observation target is focused on the image sensor by the optical system. The observation light is photoelectrically converted by the image pickup device, and an electric signal corresponding to the observation light, that is, an image signal corresponding to the observation image is generated. The image signal is transmitted as RAW data to the camera control unit (CCU: Camera Control Unit) 601.
　ＣＣＵ６０１は、ＣＰＵ（Ｃｅｎｔｒａｌ　Ｐｒｏｃｅｓｓｉｎｇ　Ｕｎｉｔ）やＧＰＵ（Ｇｒａｐｈｉｃｓ　Ｐｒｏｃｅｓｓｉｎｇ　Ｕｎｉｔ）等によって構成され、内視鏡５００及び表示装置６０２の動作を統括的に制御する。さらに、ＣＣＵ６０１は、カメラヘッド５０２から画像信号を受け取り、その画像信号に対して、例えば現像処理（デモザイク処理）等の、当該画像信号に基づく画像を表示するための各種の画像処理を施す。 The CCU 601 is composed of a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), and the like, and comprehensively controls the operations of the endoscope 500 and the display device 602. Further, the CCU 601 receives an image signal from the camera head 502, and performs various image processing on the image signal for displaying an image based on the image signal, such as a development process (demosaic process).
　表示装置６０２は、ＣＣＵ６０１からの制御により、当該ＣＣＵ６０１によって画像処理が施された画像信号に基づく画像を表示する。 The display device 602 displays an image based on the image signal processed by the CCU 601 under the control of the CCU 601.
　光源装置６０３は、例えばＬＥＤ（Ｌｉｇｈｔ　Ｅｍｉｔｔｉｎｇ　Ｄｉｏｄｅ）等の光源から構成され、術部等を撮影する際の照射光を内視鏡５００に供給する。 The light source device 603 is composed of, for example, a light source such as an LED (Light Emitting Diode), and supplies irradiation light for photographing an operating part or the like to the endoscope 500.
　入力装置６０４は、内視鏡手術システム１１０００に対する入力インタフェースである。ユーザは、入力装置６０４を介して、内視鏡手術システム４００に対して各種の情報の入力や指示入力を行うことができる。例えば、ユーザは、内視鏡５００による撮像条件（照射光の種類、倍率及び焦点距離等）を変更する旨の指示等を入力する。 The input device 604 is an input interface for the endoscopic surgery system 11000. The user can input various information and input instructions to the endoscopic surgery system 400 via the input device 604. For example, the user inputs an instruction to change the imaging conditions (type of irradiation light, magnification, focal length, etc.) by the endoscope 500.
　処置具制御装置６０５は、組織の焼灼、切開又は血管の封止等のためのエネルギー処置具５１２の駆動を制御する。気腹装置６０６は、内視鏡５００による視野の確保及び術者の作業空間の確保の目的で、患者５３２の体腔を膨らめるために、気腹チューブ５１１を介して当該体腔内にガスを送り込む。レコーダ６０７は、手術に関する各種の情報を記録可能な装置である。プリンタ６０８は、手術に関する各種の情報を、テキスト、画像又はグラフ等各種の形式で印刷可能な装置である。 The treatment tool control device 605 controls the drive of the energy treatment tool 512 for cauterizing tissue, incising, sealing a blood vessel, or the like. The pneumoperitoneum device 606 gas in the body cavity through the pneumoperitoneum tube 511 in order to inflate the body cavity of the patient 532 for the purpose of securing the field of view by the endoscope 500 and securing the work space of the operator. Is sent. The recorder 607 is a device capable of recording various information related to surgery. The printer 608 is a device capable of printing various information related to surgery in various formats such as text, images, and graphs.
　なお、内視鏡５００に術部を撮影する際の照射光を供給する光源装置６０３は、例えばＬＥＤ、レーザ光源又はこれらの組み合わせによって構成される白色光源から構成することができる。ＲＧＢレーザ光源の組み合わせにより白色光源が構成される場合には、各色（各波長）の出力強度及び出力タイミングを高精度に制御することができるため、光源装置６０３において撮像画像のホワイトバランスの調整を行うことができる。また、この場合には、ＲＧＢレーザ光源それぞれからのレーザ光を時分割で観察対象に照射し、その照射タイミングに同期してカメラヘッド５０２の撮像素子の駆動を制御することにより、ＲＧＢそれぞれに対応した画像を時分割で撮像することも可能である。当該方法によれば、当該撮像素子にカラーフィルタを設けなくても、カラー画像を得ることができる。 The light source device 603 that supplies the irradiation light to the endoscope 500 when photographing the surgical site can be composed of, for example, an LED, a laser light source, or a white light source composed of a combination thereof. When a white light source is configured by a combination of RGB laser light sources, the output intensity and output timing of each color (each wavelength) can be controlled with high accuracy. Therefore, the light source device 603 adjusts the white balance of the captured image. It can be carried out. Further, in this case, the laser light from each of the RGB laser light sources is irradiated to the observation target in a time-division manner, and the drive of the image sensor of the camera head 502 is controlled in synchronization with the irradiation timing to correspond to each of RGB. It is also possible to capture the image in a time-division manner. According to this method, a color image can be obtained without providing a color filter in the image pickup device.
　また、光源装置６０３は、出力する光の強度を所定の時間ごとに変更するようにその駆動が制御されてもよい。その光の強度の変更のタイミングに同期してカメラヘッド５０２の撮像素子の駆動を制御して時分割で画像を取得し、その画像を合成することにより、いわゆる黒つぶれ及び白とびのない高ダイナミックレンジの画像を生成することができる。 Further, the drive of the light source device 603 may be controlled so as to change the intensity of the output light at predetermined time intervals. By controlling the drive of the image sensor of the camera head 502 in synchronization with the timing of the change of the light intensity to acquire an image in time division and synthesizing the image, so-called high dynamic without blackout and overexposure. Range images can be generated.
　また、光源装置６０３は、特殊光観察に対応した所定の波長帯域の光を供給可能に構成されてもよい。特殊光観察では、例えば、体組織における光の吸収の波長依存性を利用して、通常の観察時における照射光（すなわち、白色光）に比べて狭帯域の光を照射することにより、粘膜表層の血管等の所定の組織を高コントラストで撮影する、いわゆる狭帯域光観察（Ｎａｒｒｏｗ　Ｂａｎｄ　Ｉｍａｇｉｎｇ）が行われる。あるいは、特殊光観察では、励起光を照射することにより発生する蛍光により画像を得る蛍光観察が行われてもよい。蛍光観察では、体組織に励起光を照射し当該体組織からの蛍光を観察すること（自家蛍光観察）、又はインドシアニングリーン（ＩＣＧ）等の試薬を体組織に局注するとともに当該体組織にその試薬の蛍光波長に対応した励起光を照射し蛍光像を得ること等を行うことができる。光源装置６０３は、このような特殊光観察に対応した狭帯域光及び／又は励起光を供給可能に構成され得る。 Further, the light source device 603 may be configured to be able to supply light in a predetermined wavelength band corresponding to special light observation. In special light observation, for example, by utilizing the wavelength dependence of light absorption in body tissue, the surface layer of the mucous membrane is irradiated with light in a narrower band than the irradiation light (that is, white light) during normal observation. A so-called narrow band imaging (Narrow Band Imaging) is performed in which a predetermined tissue such as a blood vessel is photographed with high contrast. Alternatively, in special light observation, fluorescence observation may be performed in which an image is obtained by fluorescence generated by irradiating with excitation light. In fluorescence observation, the body tissue is irradiated with excitation light to observe the fluorescence from the body tissue (autofluorescence observation), or a reagent such as indocyanine green (ICG) is locally injected into the body tissue and the body tissue is injected. It is possible to obtain a fluorescence image by irradiating the excitation light corresponding to the fluorescence wavelength of the reagent. The light source device 603 may be configured to be capable of supplying narrowband light and / or excitation light corresponding to such special light observation.
　図２２は、図２１に示すカメラヘッド５０２及びＣＣＵ６０１の機能構成の一例を示すブロック図である。 FIG. 22 is a block diagram showing an example of the functional configuration of the camera head 502 and CCU601 shown in FIG. 21.
　カメラヘッド５０２は、レンズユニット７０１と、撮像部７０２と、駆動部７０３と、通信部７０４と、カメラヘッド制御部７０５と、を有する。ＣＣＵ６０１は、通信部７１１と、画像処理部７１２と、制御部７１３と、を有する。カメラヘッド５０２とＣＣＵ６０１とは、伝送ケーブル７００によって互いに通信可能に接続されている。 The camera head 502 includes a lens unit 701, an image pickup unit 702, a drive unit 703, a communication unit 704, and a camera head control unit 705. The CCU 601 has a communication unit 711, an image processing unit 712, and a control unit 713. The camera head 502 and the CCU 601 are communicably connected to each other by a transmission cable 700.
　レンズユニット７０１は、鏡筒５０１との接続部に設けられる光学系である。鏡筒５０１の先端から取り込まれた観察光は、カメラヘッド５０２まで導光され、当該レンズユニット７０１に入射する。レンズユニット７０１は、ズームレンズ及びフォーカスレンズを含む複数のレンズが組み合わされて構成される。 The lens unit 701 is an optical system provided at a connection portion with the lens barrel 501. The observation light taken in from the tip of the lens barrel 501 is guided to the camera head 502 and incident on the lens unit 701. The lens unit 701 is configured by combining a plurality of lenses including a zoom lens and a focus lens.
　撮像部７０２は、撮像素子で構成される。撮像部７０２を構成する撮像素子は、１つ（いわゆる単板式）であってもよいし、複数（いわゆる多板式）であってもよい。撮像部７０２が多板式で構成される場合には、例えば各撮像素子によってＲＧＢそれぞれに対応する画像信号が生成され、それらが合成されることによりカラー画像が得られてもよい。あるいは、撮像部７０２は、３Ｄ（Ｄｉｍｅｎｓｉｏｎａｌ）表示に対応する右目用及び左目用の画像信号をそれぞれ取得するための１対の撮像素子を有するように構成されてもよい。３Ｄ表示が行われることにより、術者５３１は術部における生体組織の奥行きをより正確に把握することが可能になる。なお、撮像部７０２が多板式で構成される場合には、各撮像素子に対応して、レンズユニット７０１も複数系統設けられ得る。撮像部７０２は、例えば第１実施形態の固体撮像装置である。 The image pickup unit 702 is composed of an image pickup element. The image pickup element constituting the image pickup unit 702 may be one (so-called single plate type) or a plurality (so-called multi-plate type). When the image pickup unit 702 is composed of a multi-plate type, for example, each image pickup element may generate an image signal corresponding to each of RGB, and a color image may be obtained by synthesizing them. Alternatively, the image pickup unit 702 may be configured to have a pair of image pickup elements for acquiring image signals for the right eye and the left eye corresponding to 3D (Dimensional) display, respectively. The 3D display enables the operator 531 to more accurately grasp the depth of the living tissue in the surgical site. When the image pickup unit 702 is composed of a multi-plate type, a plurality of lens units 701 may be provided corresponding to each image pickup element. The image pickup unit 702 is, for example, the solid-state image pickup device of the first embodiment.
　また、撮像部７０２は、必ずしもカメラヘッド５０２に設けられなくてもよい。例えば、撮像部７０２は、鏡筒５０１の内部に、対物レンズの直後に設けられてもよい。 Further, the image pickup unit 702 does not necessarily have to be provided on the camera head 502. For example, the image pickup unit 702 may be provided inside the lens barrel 501 immediately after the objective lens.
　駆動部７０３は、アクチュエータによって構成され、カメラヘッド制御部７０５からの制御により、レンズユニット７０１のズームレンズ及びフォーカスレンズを光軸に沿って所定の距離だけ移動させる。これにより、撮像部７０２による撮像画像の倍率及び焦点が適宜調整され得る。 The drive unit 703 is composed of an actuator, and the zoom lens and the focus lens of the lens unit 701 are moved by a predetermined distance along the optical axis under the control of the camera head control unit 705. As a result, the magnification and focus of the image captured by the image pickup unit 702 can be adjusted as appropriate.
　通信部７０４は、ＣＣＵ６０１との間で各種の情報を送受信するための通信装置によって構成される。通信部７０４は、撮像部７０２から得た画像信号をＲＡＷデータとして伝送ケーブル７００を介してＣＣＵ６０１に送信する。 The communication unit 704 is configured by a communication device for transmitting and receiving various information to and from the CCU 601. The communication unit 704 transmits the image signal obtained from the image pickup unit 702 as RAW data to the CCU 601 via the transmission cable 700.
　また、通信部７０４は、ＣＣＵ６０１から、カメラヘッド５０２の駆動を制御するための制御信号を受信し、カメラヘッド制御部７０５に供給する。当該制御信号には、例えば、撮像画像のフレームレートを指定する旨の情報、撮像時の露出値を指定する旨の情報、並びに／又は撮像画像の倍率及び焦点を指定する旨の情報等、撮像条件に関する情報が含まれる。 Further, the communication unit 704 receives a control signal for controlling the drive of the camera head 502 from the CCU 601 and supplies the control signal to the camera head control unit 705. The control signal includes, for example, information to specify the frame rate of the captured image, information to specify the exposure value at the time of imaging, and / or information to specify the magnification and focus of the captured image. Contains information about the condition.
　なお、上記のフレームレートや露出値、倍率、焦点等の撮像条件は、ユーザによって適宜指定されてもよいし、取得された画像信号に基づいてＣＣＵ６０１の制御部７１３によって自動的に設定されてもよい。後者の場合には、いわゆるＡＥ（Ａｕｔｏ　Ｅｘｐｏｓｕｒｅ）機能、ＡＦ（Ａｕｔｏ　Ｆｏｃｕｓ）機能及びＡＷＢ（Ａｕｔｏ　Ｗｈｉｔｅ　Ｂａｌａｎｃｅ）機能が内視鏡５００に搭載されていることになる。 The image pickup conditions such as the frame rate, exposure value, magnification, and focus may be appropriately specified by the user, or may be automatically set by the control unit 713 of the CCU 601 based on the acquired image signal. good. In the latter case, the endoscope 500 is equipped with a so-called AE (Auto Exposure) function, an AF (Auto Focus) function, and an AWB (Auto White Balance) function.
　カメラヘッド制御部７０５は、通信部７０４を介して受信したＣＣＵ６０１からの制御信号に基づいて、カメラヘッド５０２の駆動を制御する。 The camera head control unit 705 controls the drive of the camera head 502 based on the control signal from the CCU 601 received via the communication unit 704.
　通信部７１１は、カメラヘッド５０２との間で各種の情報を送受信するための通信装置によって構成される。通信部７１１は、カメラヘッド５０２から、伝送ケーブル７００を介して送信される画像信号を受信する。 The communication unit 711 is composed of a communication device for transmitting and receiving various information to and from the camera head 502. The communication unit 711 receives an image signal transmitted from the camera head 502 via the transmission cable 700.
　また、通信部７１１は、カメラヘッド５０２に対して、カメラヘッド５０２の駆動を制御するための制御信号を送信する。画像信号や制御信号は、電気通信や光通信等によって送信することができる。 Further, the communication unit 711 transmits a control signal for controlling the drive of the camera head 502 to the camera head 502. Image signals and control signals can be transmitted by telecommunications, optical communication, or the like.
　画像処理部７１２は、カメラヘッド５０２から送信されたＲＡＷデータである画像信号に対して各種の画像処理を施す。 The image processing unit 712 performs various image processing on the image signal which is the RAW data transmitted from the camera head 502.
　制御部７１３は、内視鏡５００による術部等の撮像、及び、術部等の撮像により得られる撮像画像の表示に関する各種の制御を行う。例えば、制御部７１３は、カメラヘッド５０２の駆動を制御するための制御信号を生成する。 The control unit 713 performs various controls related to the imaging of the surgical site and the like by the endoscope 500 and the display of the captured image obtained by the imaging of the surgical site and the like. For example, the control unit 713 generates a control signal for controlling the drive of the camera head 502.
　また、制御部７１３は、画像処理部７１２によって画像処理が施された画像信号に基づいて、術部等が映った撮像画像を表示装置６０２に表示させる。この際、制御部７１３は、各種の画像認識技術を用いて撮像画像内における各種の物体を認識してもよい。例えば、制御部７１３は、撮像画像に含まれる物体のエッジの形状や色等を検出することにより、鉗子等の術具、特定の生体部位、出血、エネルギー処置具５１２の使用時のミスト等を認識することができる。制御部７１３は、表示装置６０２に撮像画像を表示させる際に、その認識結果を用いて、各種の手術支援情報を当該術部の画像に重畳表示させてもよい。手術支援情報が重畳表示され、術者５３１に提示されることにより、術者５３１の負担を軽減することや、術者５３１が確実に手術を進めることが可能になる。 Further, the control unit 713 causes the display device 602 to display an image captured by the surgical unit or the like based on the image signal processed by the image processing unit 712. At this time, the control unit 713 may recognize various objects in the captured image by using various image recognition techniques. For example, the control unit 713 detects a surgical tool such as forceps, a specific biological part, bleeding, mist when using the energy treatment tool 512, etc. by detecting the shape, color, etc. of the edge of the object included in the captured image. Can be recognized. When the control unit 713 displays the captured image on the display device 602, the control unit 713 may superimpose and display various surgical support information on the image of the surgical unit by using the recognition result. By superimposing and displaying the surgery support information and presenting it to the surgeon 531 it is possible to reduce the burden on the surgeon 531 and to ensure that the surgeon 531 can proceed with the surgery.
　カメラヘッド５０２及びＣＣＵ６０１を接続する伝送ケーブル７００は、電気信号の通信に対応した電気信号ケーブル、光通信に対応した光ファイバ、又はこれらの複合ケーブルである。 The transmission cable 700 connecting the camera head 502 and the CCU 601 is an electric signal cable compatible with electric signal communication, an optical fiber compatible with optical communication, or a composite cable thereof.
　ここで、図示する例では、伝送ケーブル７００を用いて有線で通信が行われていたが、カメラヘッド５０２とＣＣＵ６０１との間の通信は無線で行われてもよい。 Here, in the illustrated example, the communication is performed by wire using the transmission cable 700, but the communication between the camera head 502 and the CCU 601 may be performed wirelessly.
　以上、本開示の実施形態について説明したが、本開示の実施形態は、本開示の要旨を逸脱しない範囲内で、種々の変更を加えて実施してもよい。例えば、２つ以上の実施形態を組み合わせて実施してもよい。 Although the embodiments of the present disclosure have been described above, the embodiments of the present disclosure may be implemented with various modifications without departing from the gist of the present disclosure. For example, two or more embodiments may be combined and carried out.
　なお、本開示は、以下のような構成を取ることもできる。 Note that this disclosure can also have the following structure.
　（１）
　光入射面の反対面となる第１面と、前記光入射面となる第２面とを有する基板と、
　前記基板内に設けられた第１光電変換部と第１電荷蓄積部とを有する第１画素と、
　前記基板内に設けられた第２光電変換部と第２電荷蓄積部とを有する第２画素と、
　前記基板内にて、隣接する前記第２光電変換部と前記第１電荷蓄積部との間に設けられた第１遮光膜と、
　前記基板の前記第１面側に設けられた多層配線層と、
　前記多層配線層内に設けられ、前記第１遮光膜に接している第２遮光膜と、
　を備える固体撮像装置。 (1)
A substrate having a first surface that is opposite to the light incident surface and a second surface that is the light incident surface.
A first pixel having a first photoelectric conversion unit and a first charge storage unit provided in the substrate, and
A second pixel having a second photoelectric conversion unit and a second charge storage unit provided in the substrate, and
A first light-shielding film provided between the second photoelectric conversion unit and the first charge storage unit adjacent to each other in the substrate.
A multilayer wiring layer provided on the first surface side of the substrate, and
A second light-shielding film provided in the multilayer wiring layer and in contact with the first light-shielding film, and
A solid-state image sensor.
　（２）
　前記基板の前記第２面上に設けられ、前記第１電荷蓄積部と平面視で重なっており、前記第１遮光膜に接している第３遮光膜をさらに備える、（１）に記載の固体撮像装置。 (2)
The solid according to (1), further comprising a third light-shielding film provided on the second surface of the substrate, overlapping with the first charge storage portion in a plan view, and in contact with the first light-shielding film. Image sensor.
　（３）
　前記第１遮光膜の幅は、前記第１面側から前記第２面側に進むにつれ狭くなっている、（１）に記載の固体撮像装置。 (3)
The solid-state image sensor according to (1), wherein the width of the first light-shielding film becomes narrower from the first surface side to the second surface side.
　（４）
　前記多層配線層は、前記基板の前記第１面に設けられた絶縁層を含み、
　前記第１遮光膜は、前記基板内および前記絶縁層内に設けられている、（１）に記載の固体撮像装置。 (4)
The multilayer wiring layer includes an insulating layer provided on the first surface of the substrate.
The solid-state image sensor according to (1), wherein the first light-shielding film is provided in the substrate and the insulating layer.
　（５）
　前記絶縁膜は、トランジスタのゲート絶縁膜として機能する、（４）に記載の固体撮像装置。 (5)
The solid-state image sensor according to (4), wherein the insulating film functions as a gate insulating film of a transistor.
　（６）
　前記第２遮光膜は、前記第１遮光膜と、前記トランジスタの電極層とに接している、（５）に記載の固体撮像装置。 (6)
The solid-state image pickup apparatus according to (5), wherein the second light-shielding film is in contact with the first light-shielding film and the electrode layer of the transistor.
　（７）
　前記第１遮光膜は、前記基板を貫通する第１溝内に設けられている、（１）に記載の固体撮像装置。 (7)
The solid-state image sensor according to (1), wherein the first light-shielding film is provided in a first groove penetrating the substrate.
　（８）
　前記第１溝の幅は、前記第１面側から前記第２面側に進むにつれ狭くなっている、（７）に記載の固体撮像装置。 (8)
The solid-state image sensor according to (7), wherein the width of the first groove becomes narrower from the first surface side to the second surface side.
　（９）
　前記第３遮光膜は、前記基板の前記第２面上と、前記基板を貫通しない第２溝内とに設けられている、（２）に記載の固体撮像装置。 (9)
The solid-state image sensor according to (2), wherein the third light-shielding film is provided on the second surface of the substrate and in a second groove that does not penetrate the substrate.
　（１０）
　前記第２溝の幅は、前記第１面側から前記第２面側に進むにつれ広くなっている、（９）に記載の固体撮像装置。 (10)
The solid-state image sensor according to (9), wherein the width of the second groove becomes wider from the first surface side to the second surface side.
　（１１）
　光入射面の反対面となる第１面と、前記光入射面となる第２面とを有する基板と、
　前記基板内に設けられた第１光電変換部と第１電荷蓄積部とを有する第１画素と、
　前記基板内に設けられた第２光電変換部と第２電荷蓄積部とを有する第２画素と、
　前記基板を貫通しており、隣接する前記第２光電変換部と前記第１電荷蓄積部との間に設けられた第１溝であって、前記基板内にて前記第１面側に設けられた第１部分と、前記基板内にて前記第２面側に設けられた第２部分とを含む第１溝と、
　前記第１部分内に設けられた第１遮光膜と、
　前記基板の前記第１面側に設けられた多層配線層と、
　前記多層配線層内に設けられ、前記第１遮光膜に接している第２遮光膜と、
　を備える固体撮像装置。 (11)
A substrate having a first surface that is opposite to the light incident surface and a second surface that is the light incident surface.
A first pixel having a first photoelectric conversion unit and a first charge storage unit provided in the substrate, and
A second pixel having a second photoelectric conversion unit and a second charge storage unit provided in the substrate, and
A first groove that penetrates the substrate and is provided between the adjacent second photoelectric conversion unit and the first charge storage unit, and is provided on the first surface side in the substrate. A first groove including a first portion and a second portion provided on the second surface side in the substrate.
The first light-shielding film provided in the first portion and
A multilayer wiring layer provided on the first surface side of the substrate, and
A second light-shielding film provided in the multilayer wiring layer and in contact with the first light-shielding film, and
A solid-state image sensor.
　（１２）
　前記第１部分の幅は、前記第１面側から前記第２面側に進むにつれ狭くなっており、
　前記第２部分の幅は、前記第１面側から前記第２面側に進むにつれ広くなっている、
　（１１）に記載の固体撮像装置。 (12)
The width of the first portion becomes narrower from the first surface side to the second surface side.
The width of the second portion becomes wider from the first surface side to the second surface side.
The solid-state image sensor according to (11).
　（１３）
　前記基板の前記第２面上と、前記第２部分内とに設けられ、前記第１電荷蓄積部と平面視で重なっている第３遮光膜をさらに備える、（１１）に記載の固体撮像装置。 (13)
The solid-state image pickup device according to (11), further comprising a third light-shielding film provided on the second surface of the substrate and in the second portion and overlapping with the first charge storage portion in a plan view. ..
　（１４）
　前記第３遮光膜はさらに、前記基板を貫通しない第２溝内に設けられている、（１３）に記載の固体撮像装置。 (14)
The solid-state image sensor according to (13), wherein the third light-shielding film is further provided in a second groove that does not penetrate the substrate.
　（１５）
　前記第２溝の幅は、前記第１面側から前記第２面側に進むにつれ広くなっている、（１４）に記載の固体撮像装置。 (15)
The solid-state image sensor according to (14), wherein the width of the second groove becomes wider from the first surface side to the second surface side.
　（１６）
　前記第１溝と前記第２溝は、前記基板内で互いにつながっている、（１４）に記載の固体撮像装置。 (16)
The solid-state image sensor according to (14), wherein the first groove and the second groove are connected to each other in the substrate.
　（１７）
　光入射面の反対面となる第１面と、前記光入射面となる第２面とを有する基板を用意し、
　前記基板内に第１光電変換部と第１電荷蓄積部とを有する第１画素を形成し、
　前記基板内に第２光電変換部と第２電荷蓄積部とを有する第２画素を形成し、
　前記基板内にて、隣接する前記第２光電変換部と前記第１電荷蓄積部との間に第１遮光膜を形成し、
　前記基板の前記第１面側に多層配線層を形成し、
　前記多層配線層内に、前記第１遮光膜に接する第２遮光膜を形成する、
　ことを含む固体撮像装置の製造方法。 (17)
A substrate having a first surface opposite to the light incident surface and a second surface to be the light incident surface is prepared.
A first pixel having a first photoelectric conversion unit and a first charge storage unit is formed in the substrate.
A second pixel having a second photoelectric conversion unit and a second charge storage unit is formed in the substrate.
In the substrate, a first light-shielding film is formed between the adjacent second photoelectric conversion unit and the first charge storage unit.
A multilayer wiring layer is formed on the first surface side of the substrate, and the multilayer wiring layer is formed.
A second light-shielding film in contact with the first light-shielding film is formed in the multilayer wiring layer.
A method of manufacturing a solid-state image sensor, including the above.
　（１８）
　前記基板を貫通する第１溝を形成することをさらに含み、
　前記第１遮光膜は、前記基板の前記第１面側から前記第１溝内に形成される、
　（１７）に記載の固体撮像装置の製造方法。 (18)
Further comprising forming a first groove penetrating the substrate.
The first light-shielding film is formed in the first groove from the first surface side of the substrate.
(17) The method for manufacturing a solid-state image sensor according to (17).
　（１９）
　前記基板の前記第２面上に、前記第１電荷蓄積部と平面視で重なり、前記第１遮光膜に接する第３遮光膜を形成することをさらに含む、（１７）に記載の固体撮像装置の製造方法。 (19)
The solid-state image pickup apparatus according to (17), further comprising forming a third light-shielding film on the second surface of the substrate, which overlaps with the first charge storage portion in a plan view and is in contact with the first light-shielding film. Manufacturing method.
　（２０）
　前記基板を貫通しない第２溝を形成することをさらに含み、
　前記第３遮光膜は、前記基板の前記第２面に形成され、かつ、前記基板の前記第２面側から前記第２溝内に形成される、
　（１９）に記載の固体撮像装置の製造方法。 (20)
Further comprising forming a second groove that does not penetrate the substrate.
The third light-shielding film is formed on the second surface of the substrate and is formed in the second groove from the second surface side of the substrate.
(19) The method for manufacturing a solid-state image sensor according to (19).
　１：画素、２：画素アレイ領域、３：制御回路、
　４：垂直駆動回路、５：カラム信号処理回路、６：水平駆動回路、
　７：出力回路、８：垂直信号線、９：水平信号線、
　１１：基板、１２：光電変換部、１３：ｐ＋型半導体領域、１４：ｎ－型半導体領域、
　１５：ｐ型半導体領域、１６：メモリ部、１７：ｐ＋型半導体領域、
　１８：ｎ－型半導体領域、１９：ｐ型半導体領域、２０：その他の半導体領域、
　２１：溝、２１ａ：第１部分、２１ｂ：第２部分、２２：絶縁膜、２３：遮光膜、
　２４：溝、２５：第１絶縁膜、２６：第２絶縁膜、２７：遮光膜、
　２８：平坦化膜、２９：カラーフィルタ、３０：オンチップレンズ、
　３１：絶縁層、３１ａ：第１絶縁膜、３１ｂ：第２絶縁膜、３１ｃ：第３絶縁膜、
　３２：層間絶縁膜、３３：電極層、３４：遮光膜、３５：コンタクトプラグ、
　３６：配線層、３７：配線層、３８：配線層、３９：配線層、４０：ビアプラグ、
　４１：支持基板、４２：層、５１：絶縁膜 1: Pixel 2: Pixel array area 3: Control circuit,
4: Vertical drive circuit, 5: Column signal processing circuit, 6: Horizontal drive circuit,
7: Output circuit, 8: Vertical signal line, 9: Horizontal signal line,
11: Substrate, 12: Photoelectric conversion unit, 13: p + type semiconductor region, 14: n-type semiconductor region,
15: p-type semiconductor area, 16: memory unit, 17: p + type semiconductor area,
18: n-type semiconductor region, 19: p-type semiconductor region, 20: other semiconductor region,
21: groove, 21a: first part, 21b: second part, 22: insulating film, 23: light-shielding film,
24: groove, 25: first insulating film, 26: second insulating film, 27: light-shielding film,
28: Flattening film, 29: Color filter, 30: On-chip lens,
31: Insulation layer, 31a: First insulating film, 31b: Second insulating film, 31c: Third insulating film,
32: interlayer insulating film, 33: electrode layer, 34: light-shielding film, 35: contact plug,
36: Wiring layer, 37: Wiring layer, 38: Wiring layer, 39: Wiring layer, 40: Via plug,
41: Support substrate, 42: Layer, 51: Insulating film

Claims (20)

  1. 　光入射面の反対面となる第１面と、前記光入射面となる第２面とを有する基板と、
    　前記基板内に設けられた第１光電変換部と第１電荷蓄積部とを有する第１画素と、
    　前記基板内に設けられた第２光電変換部と第２電荷蓄積部とを有する第２画素と、
    　前記基板内にて、隣接する前記第２光電変換部と前記第１電荷蓄積部との間に設けられた第１遮光膜と、
    　前記基板の前記第１面側に設けられた多層配線層と、
    　前記多層配線層内に設けられ、前記第１遮光膜に接している第２遮光膜と、
    　を備える固体撮像装置。     A substrate having a first surface that is opposite to the light incident surface and a second surface that is the light incident surface.
    A first pixel having a first photoelectric conversion unit and a first charge storage unit provided in the substrate, and
    A second pixel having a second photoelectric conversion unit and a second charge storage unit provided in the substrate, and
    A first light-shielding film provided between the second photoelectric conversion unit and the first charge storage unit adjacent to each other in the substrate.
    A multilayer wiring layer provided on the first surface side of the substrate, and
    A second light-shielding film provided in the multilayer wiring layer and in contact with the first light-shielding film, and
    A solid-state image sensor.
  2. 　前記基板の前記第２面上に設けられ、前記第１電荷蓄積部と平面視で重なっており、前記第１遮光膜に接している第３遮光膜をさらに備える、請求項１に記載の固体撮像装置。 The solid according to claim 1, further comprising a third light-shielding film provided on the second surface of the substrate, overlapping with the first charge storage portion in a plan view, and in contact with the first light-shielding film. Image sensor.
  3. 　前記第１遮光膜の幅は、前記第１面側から前記第２面側に進むにつれ狭くなっている、請求項１に記載の固体撮像装置。 The solid-state image sensor according to claim 1, wherein the width of the first light-shielding film becomes narrower from the first surface side to the second surface side.
  4. 　前記多層配線層は、前記基板の前記第１面に設けられた絶縁層を含み、
    　前記第１遮光膜は、前記基板内および前記絶縁層内に設けられている、請求項１に記載の固体撮像装置。     The multilayer wiring layer includes an insulating layer provided on the first surface of the substrate.
    The solid-state image sensor according to claim 1, wherein the first light-shielding film is provided in the substrate and the insulating layer.
  5. 　前記絶縁膜は、トランジスタのゲート絶縁膜として機能する、請求項４に記載の固体撮像装置。 The solid-state image sensor according to claim 4, wherein the insulating film functions as a gate insulating film of a transistor.
  6. 　前記第２遮光膜は、前記第１遮光膜と、前記トランジスタの電極層とに接している、請求項５に記載の固体撮像装置。 The solid-state image sensor according to claim 5, wherein the second light-shielding film is in contact with the first light-shielding film and the electrode layer of the transistor.
  7. 　前記第１遮光膜は、前記基板を貫通する第１溝内に設けられている、請求項１に記載の固体撮像装置。 The solid-state image sensor according to claim 1, wherein the first light-shielding film is provided in a first groove penetrating the substrate.
  8. 　前記第１溝の幅は、前記第１面側から前記第２面側に進むにつれ狭くなっている、請求項７に記載の固体撮像装置。 The solid-state image sensor according to claim 7, wherein the width of the first groove becomes narrower from the first surface side to the second surface side.
  9. 　前記第３遮光膜は、前記基板の前記第２面上と、前記基板を貫通しない第２溝内とに設けられている、請求項２に記載の固体撮像装置。 The solid-state image sensor according to claim 2, wherein the third light-shielding film is provided on the second surface of the substrate and in a second groove that does not penetrate the substrate.
  10. 　前記第２溝の幅は、前記第１面側から前記第２面側に進むにつれ広くなっている、請求項９に記載の固体撮像装置。 The solid-state image pickup device according to claim 9, wherein the width of the second groove becomes wider from the first surface side to the second surface side.
  11. 　光入射面の反対面となる第１面と、前記光入射面となる第２面とを有する基板と、
    　前記基板内に設けられた第１光電変換部と第１電荷蓄積部とを有する第１画素と、
    　前記基板内に設けられた第２光電変換部と第２電荷蓄積部とを有する第２画素と、
    　前記基板を貫通しており、隣接する前記第２光電変換部と前記第１電荷蓄積部との間に設けられた第１溝であって、前記基板内にて前記第１面側に設けられた第１部分と、前記基板内にて前記第２面側に設けられた第２部分とを含む第１溝と、
    　前記第１部分内に設けられた第１遮光膜と、
    　前記基板の前記第１面側に設けられた多層配線層と、
    　前記多層配線層内に設けられ、前記第１遮光膜に接している第２遮光膜と、
    　を備える固体撮像装置。     A substrate having a first surface that is opposite to the light incident surface and a second surface that is the light incident surface.
    A first pixel having a first photoelectric conversion unit and a first charge storage unit provided in the substrate, and
    A second pixel having a second photoelectric conversion unit and a second charge storage unit provided in the substrate, and
    A first groove that penetrates the substrate and is provided between the adjacent second photoelectric conversion unit and the first charge storage unit, and is provided on the first surface side in the substrate. A first groove including a first portion and a second portion provided on the second surface side in the substrate.
    The first light-shielding film provided in the first portion and
    A multilayer wiring layer provided on the first surface side of the substrate, and
    A second light-shielding film provided in the multilayer wiring layer and in contact with the first light-shielding film, and
    A solid-state image sensor.
  12. 　前記第１部分の幅は、前記第１面側から前記第２面側に進むにつれ狭くなっており、
    　前記第２部分の幅は、前記第１面側から前記第２面側に進むにつれ広くなっている、
    　請求項１１に記載の固体撮像装置。     The width of the first portion becomes narrower from the first surface side to the second surface side.
    The width of the second portion becomes wider from the first surface side to the second surface side.
    The solid-state image sensor according to claim 11.
  13. 　前記基板の前記第２面上と、前記第２部分内とに設けられ、前記第１電荷蓄積部と平面視で重なっている第３遮光膜をさらに備える、請求項１１に記載の固体撮像装置。 The solid-state image pickup apparatus according to claim 11, further comprising a third light-shielding film provided on the second surface of the substrate and in the second portion and overlapping with the first charge storage portion in a plan view. ..
  14. 　前記第３遮光膜はさらに、前記基板を貫通しない第２溝内に設けられている、請求項１３に記載の固体撮像装置。 The solid-state image sensor according to claim 13, wherein the third light-shielding film is further provided in a second groove that does not penetrate the substrate.
  15. 　前記第２溝の幅は、前記第１面側から前記第２面側に進むにつれ広くなっている、請求項１４に記載の固体撮像装置。 The solid-state image pickup device according to claim 14, wherein the width of the second groove becomes wider from the first surface side to the second surface side.
  16. 　前記第１溝と前記第２溝は、前記基板内で互いにつながっている、請求項１４に記載の固体撮像装置。 The solid-state image sensor according to claim 14, wherein the first groove and the second groove are connected to each other in the substrate.
  17. 　光入射面の反対面となる第１面と、前記光入射面となる第２面とを有する基板を用意し、
    　前記基板内に第１光電変換部と第１電荷蓄積部とを有する第１画素を形成し、
    　前記基板内に第２光電変換部と第２電荷蓄積部とを有する第２画素を形成し、
    　前記基板内にて、隣接する前記第２光電変換部と前記第１電荷蓄積部との間に第１遮光膜を形成し、
    　前記基板の前記第１面側に多層配線層を形成し、
    　前記多層配線層内に、前記第１遮光膜に接する第２遮光膜を形成する、
    　ことを含む固体撮像装置の製造方法。     A substrate having a first surface opposite to the light incident surface and a second surface to be the light incident surface is prepared.
    A first pixel having a first photoelectric conversion unit and a first charge storage unit is formed in the substrate.
    A second pixel having a second photoelectric conversion unit and a second charge storage unit is formed in the substrate.
    In the substrate, a first light-shielding film is formed between the adjacent second photoelectric conversion unit and the first charge storage unit.
    A multilayer wiring layer is formed on the first surface side of the substrate, and the multilayer wiring layer is formed.
    A second light-shielding film in contact with the first light-shielding film is formed in the multilayer wiring layer.
    A method of manufacturing a solid-state image sensor, including the above.
  18. 　前記基板を貫通する第１溝を形成することをさらに含み、
    　前記第１遮光膜は、前記基板の前記第１面側から前記第１溝内に形成される、
    　請求項１７に記載の固体撮像装置の製造方法。     Further comprising forming a first groove penetrating the substrate.
    The first light-shielding film is formed in the first groove from the first surface side of the substrate.
    The method for manufacturing a solid-state image sensor according to claim 17.
  19. 　前記基板の前記第２面上に、前記第１電荷蓄積部と平面視で重なり、前記第１遮光膜に接する第３遮光膜を形成することをさらに含む、請求項１７に記載の固体撮像装置の製造方法。 The solid-state image pickup apparatus according to claim 17, further comprising forming a third light-shielding film on the second surface of the substrate, which overlaps with the first charge storage portion in a plan view and is in contact with the first light-shielding film. Manufacturing method.
  20. 　前記基板を貫通しない第２溝を形成することをさらに含み、
    　前記第３遮光膜は、前記基板の前記第２面に形成され、かつ、前記基板の前記第２面側から前記第２溝内に形成される、
    　請求項１９に記載の固体撮像装置の製造方法。     Further comprising forming a second groove that does not penetrate the substrate.
    The third light-shielding film is formed on the second surface of the substrate and is formed in the second groove from the second surface side of the substrate.
    The method for manufacturing a solid-state image sensor according to claim 19.
PCT/JP2021/044167 2020-12-15 2021-12-01 Solid-state imaging device and method for manufacturing same WO2022130987A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2020-207782 2020-12-15
JP2020207782A JP2022094727A (en) 2020-12-15 2020-12-15 Solid-state imaging device and method for manufacturing the same

Publications (1)

Publication Number Publication Date
WO2022130987A1 true WO2022130987A1 (en) 2022-06-23

Family

ID=82057573

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2021/044167 WO2022130987A1 (en) 2020-12-15 2021-12-01 Solid-state imaging device and method for manufacturing same

Country Status (2)

Country Link
JP (1) JP2022094727A (en)
WO (1) WO2022130987A1 (en)

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013065688A (en) * 2011-09-16 2013-04-11 Sony Corp Solid state imaging element, manufacturing method, and electronic apparatus
JP2018148116A (en) * 2017-03-08 2018-09-20 ソニーセミコンダクタソリューションズ株式会社 Solid state image sensor, and electronic equipment
JP2018160485A (en) * 2017-03-22 2018-10-11 ソニーセミコンダクタソリューションズ株式会社 Imaging element and electronic equipment
JP2018198272A (en) * 2017-05-24 2018-12-13 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 apparatus
WO2019130820A1 (en) * 2017-12-26 2019-07-04 ソニーセミコンダクタソリューションズ株式会社 Imaging element and imaging device
JP2020181947A (en) * 2019-04-26 2020-11-05 キヤノン株式会社 Photoelectric conversion device, imaging system, and mobile body

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013065688A (en) * 2011-09-16 2013-04-11 Sony Corp Solid state imaging element, manufacturing method, and electronic apparatus
JP2018148116A (en) * 2017-03-08 2018-09-20 ソニーセミコンダクタソリューションズ株式会社 Solid state image sensor, and electronic equipment
JP2018160485A (en) * 2017-03-22 2018-10-11 ソニーセミコンダクタソリューションズ株式会社 Imaging element and electronic equipment
JP2018198272A (en) * 2017-05-24 2018-12-13 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 apparatus
WO2019130820A1 (en) * 2017-12-26 2019-07-04 ソニーセミコンダクタソリューションズ株式会社 Imaging element and imaging device
JP2020181947A (en) * 2019-04-26 2020-11-05 キヤノン株式会社 Photoelectric conversion device, imaging system, and mobile body

Also Published As

Publication number Publication date
JP2022094727A (en) 2022-06-27

Similar Documents

Publication Publication Date Title
JP6951866B2 (en) Image sensor
JP2019012739A (en) Solid state imaging device and imaging apparatus
WO2020137285A1 (en) Imaging element and method for manufacturing imaging element
WO2021124975A1 (en) Solid-state imaging device and electronic instrument
JPWO2020137203A1 (en) Image sensor and image sensor
JP2019192802A (en) Imaging device and manufacturing method of imaging device
US20230103730A1 (en) Solid-state imaging device
WO2021100332A1 (en) Semiconductor device, solid-state image capturing device, and electronic device
WO2020261817A1 (en) Solid-state imaging element and method for manufacturing solid-state imaging element
WO2022172711A1 (en) Photoelectric conversion element and electronic device
WO2021045139A1 (en) Imaging element and imaging device
WO2021186907A1 (en) Solid-state imaging device, method for manufacturing same, and electronic instrument
WO2020195180A1 (en) Imaging element and imaging device
WO2022130987A1 (en) Solid-state imaging device and method for manufacturing same
WO2022138097A1 (en) Solid-state imaging device and method for manufacturing same
WO2022085695A1 (en) Solid-state imaging device
WO2023021787A1 (en) Optical detection device and method for manufacturing same
US20240038807A1 (en) Solid-state imaging device
WO2023105783A1 (en) Solid-state imaging device and method for manufacturing same
WO2022249678A1 (en) Solid-state imaging device and method for manufacturing same
WO2024024269A1 (en) Solid-state imaging device and method for manufacturing same
WO2021187151A1 (en) Image-capturing element, semiconductor chip
WO2024029408A1 (en) Imaging device
WO2021140958A1 (en) Imaging element, manufacturing method, and electronic device
WO2024057814A1 (en) Light-detection device and electronic instrument

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21906350

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 21906350

Country of ref document: EP

Kind code of ref document: A1