Image sensor and image pickup device

Abstract

The present invention reduces a phase difference detection error in an imaging element provided with phase difference pixels configured by disposing an on-chip lens common to a pair of pixels.　This imaging element comprises a pixel, an individual on-chip lens, a plurality of phase difference pixels, a common on-chip lens, and a pixel circuit. The pixel is provided with a photoelectric conversion part that performs a photoelectric conversion in response to incident light, and a charge transfer part that transfers a charge generated by the photoelectric conversion. The individual on-chip lens is disposed in each pixel, and individually collects the incident light. The phase difference pixels are each provided with a photoelectric conversion part and a charge transfer part, are disposed adjacent to each other, and detect a phase difference. The common on-chip lens is disposed to be common to the plurality of phase difference pixels, and collects the incident light in common. The pixel circuit is formed on a semiconductor substrate and generates an image signal on the basis of the transferred charge. The charge transfer parts of the plurality of phase difference pixels are disposed in a region between the common on-chip lens and the individual on-chip lens.

Description

[Technical field]

[0001] The present disclosure relates to an imaging element and an imaging device, and more particularly to an imaging element that detects a phase difference of a subject and an imaging device that uses the imaging element. [Background technology]

[0002] Conventionally, in a back-illuminated imaging element in which light from a subject is irradiated onto the back side of a semiconductor substrate on which photoelectric conversion elements such as photodiodes are formed, an imaging element is used that transfers electric charges generated by photoelectric conversion on the back side of the semiconductor substrate to the front side of the semiconductor substrate. For example, an imaging element is used in which an organic photoelectric conversion film is disposed adjacent to the back side of the semiconductor substrate, and electric charges generated by photoelectric conversion in this organic photoelectric conversion film are transferred to the front side of the semiconductor substrate by a through electrode (see, for example, Patent Document 1). The electric charges transferred by the through electrode are converted into an image signal by a circuit element disposed on the front side of the semiconductor substrate. In addition, the through electrode is disposed between pixels, which is an area between pixels that is a unit of photoelectric conversion of incident light.

[0003] Phase difference pixels have also been proposed for this imaging element. Here, the phase difference pixel is a pixel for detecting the phase difference of the subject. The detected phase difference can be used to detect the focal position of the subject and to autofocus the imaging lens. The phase difference can be detected by pupil division. This pupil division is a method of detecting the phase difference by arranging a pair of pixels that convert the incident light transmitted through the right and left sides of the imaging lens into image signals. The focal position can be detected by detecting the phase difference between the image based on the image signal transmitted through the right side of the imaging lens and the image transmitted through the right side. The phase difference pixel used for pupil division can be configured by a pixel with the left or right side of the pixel shielded from light. By irradiating the pixel with the left and right sides of the pixel shielded from light with the incident light collected by the on-chip lens, the incident light transmitted through the right and left sides of the imaging lens can be photoelectrically converted. However, due to the light shielding, the output of the image signal of the phase difference pixel is reduced by half. There is a problem in that the detection accuracy of the phase difference is reduced.

[0004] Therefore, a method has been proposed in which a common on-chip lens (common on-chip lens) is placed between two adjacent pixels to perform pupil division. By using the common on-chip lens to focus the incident light between the two pixels, it is possible to perform photoelectric conversion of the incident light that has passed through the right and left sides of the photographing lens. Since the pixels are not shaded, it is possible to prevent a decrease in the output of the image signal. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] International Publication No. 2016 / 143531 Summary of the Invention [Problem to be solved by the invention]

[0006] In the above-mentioned conventional technology, when a pupil division method using a common on-chip lens is applied, there is a problem that the detection accuracy of the phase difference is reduced. Since the common on-chip lens collects incident light between pixels, if a structure that does not contribute to photoelectric conversion, such as the above-mentioned through electrode, is placed between the pixels, a difference occurs between the image signals of a pair of phase difference pixels, and an error in phase difference detection increases.

[0007] The present disclosure has been made in consideration of the above-described problems, and aims to reduce errors in phase difference detection in an image sensor including phase difference pixels configured by disposing an on-chip lens common to a pair of pixels. [Means for solving the problem]

[0008] The present disclosure has been made to solve the above-mentioned problems, and a first aspect thereof is an imaging element comprising: a pixel including a photoelectric conversion unit that performs photoelectric conversion in response to incident light and a charge transfer unit that transfers charges generated by the photoelectric conversion; an individual on-chip lens that is arranged for each of the pixels and individually collects the incident light; a plurality of phase difference pixels that each include the photoelectric conversion unit and the charge transfer unit and are arranged adjacent to each other to detect a phase difference; a common on-chip lens that is arranged in common to the plurality of phase difference pixels and commonly collects the incident light; and a pixel circuit that is formed on a semiconductor substrate and generates an image signal based on the transferred charges, and the charge transfer units of the plurality of phase difference pixels are arranged in a region between the common on-chip lens and the individual on-chip lenses.

[0009] In the first aspect, the pixel circuit may be formed on the front surface side of the semiconductor substrate.

[0010] In the first aspect, the photoelectric conversion section may be formed on the semiconductor substrate and perform photoelectric conversion of the incident light incident on a back surface that is different from the front surface.

[0011] In the first aspect, the charge transfer section may be formed of a vertical transistor that transfers charges in a thickness direction of the semiconductor substrate.

[0012] In the first aspect, the photoelectric conversion section may be formed of a photoelectric conversion film disposed adjacent to the back surface side of the semiconductor substrate.

[0013] In the first aspect, the charge transfer section may be formed of a through electrode that is an electrode that penetrates the semiconductor substrate.

[0014] In addition, in the first aspect, a color filter that transmits light of a predetermined wavelength out of the incident light may be further provided.

[0015] In the first aspect, the color filter may be disposed between the individual on-chip lens and the photoelectric conversion film, and between the common on-chip lens and the photoelectric conversion film.

[0016] In the first aspect, the color filter may be disposed between the photoelectric conversion film and the semiconductor substrate.

[0017] In addition, in the first aspect, a separator disposed between the photoelectric conversion units of the phase difference pixels may be further provided.

[0018] A second aspect of the present disclosure is an imaging device including: pixels including a photoelectric conversion unit that performs photoelectric conversion in response to incident light and a charge transfer unit that transfers charges generated by the photoelectric conversion; individual on-chip lenses that are arranged for each of the pixels and individually collect the incident light; a plurality of phase difference pixels that each include the photoelectric conversion unit and the charge transfer unit and are arranged adjacent to each other to detect a phase difference; a common on-chip lens that is arranged in common to the plurality of phase difference pixels and commonly collects the incident light; a pixel circuit that is formed on a semiconductor substrate and generates an image signal based on the transferred charges; and a processing circuit that processes the generated image signal, wherein the charge transfer units of the plurality of phase difference pixels are arranged in an area between the common on-chip lens and the individual on-chip lenses.

[0019] By adopting the above-mentioned aspect, the charge transfer unit is disposed in a region different from the region in which the common on-chip lens is disposed in a plan view, and it is expected that the influence of the charge transfer unit on the light collection by the common on-chip lens is reduced. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a diagram illustrating an example of a configuration of an imaging element according to an embodiment of the present disclosure. [Diagram 2] 1 is a circuit diagram illustrating a configuration example of a pixel according to a first embodiment of the present disclosure. [Diagram 3] 1 is a cross-sectional view showing a configuration example of a pixel according to a first embodiment of the present disclosure. [Figure 4] 2 is a diagram illustrating a configuration example of a pixel array unit according to the first embodiment of the present disclosure. FIG. [Diagram 5] 1 is a cross-sectional view illustrating a configuration example of a phase difference pixel according to a first embodiment of the present disclosure. [Figure 6] FIG. 11 is a cross-sectional view illustrating a configuration example of a phase difference pixel according to a second embodiment of the present disclosure. [Figure 7] FIG. 13 is a circuit diagram illustrating a configuration example of a pixel according to a third embodiment of the present disclosure. [Figure 8] FIG. 11 is a cross-sectional view showing a configuration example of a pixel according to a third embodiment of the present disclosure. [Figure 9] FIG. 13 is a diagram illustrating a configuration example of a pixel array unit according to a third embodiment of the present disclosure. [Figure 10] FIG. 13 is a circuit diagram illustrating a configuration example of a pixel according to a fourth embodiment of the present disclosure. [Figure 11] FIG. 13 is a cross-sectional view showing a configuration example of a pixel according to a fourth embodiment of the present disclosure. [Figure 12] FIG. 13 is a diagram illustrating a configuration example of a pixel array unit according to a fourth embodiment of the present disclosure. [Figure 13] FIG. 13 is a cross-sectional view showing a configuration example of a pixel according to a fifth embodiment of the present disclosure. [Figure 14] FIG. 13 is a cross-sectional view showing a configuration example of a pixel according to a sixth embodiment of the present disclosure. [Figure 15] FIG. 13 is a circuit diagram illustrating a configuration example of a pixel according to a seventh embodiment of the present disclosure. [Figure 16] FIG. 13 is a cross-sectional view showing a configuration example of a pixel according to a seventh embodiment of the present disclosure. [Figure 17] FIG. 13 is a diagram illustrating a configuration example of a pixel array unit according to a seventh embodiment of the present disclosure. [Figure 18] 1 is a block diagram showing a schematic configuration example of a camera that is an example of an imaging device to which the present technology can be applied. [Figure 19] 1 is a diagram illustrating an example of a schematic configuration of an endoscopic surgery system. [Figure 20] 2 is a block diagram showing an example of a functional configuration of a camera head and a CCU. FIG. [Figure 21] 1 is a block diagram showing an example of a schematic configuration of a vehicle control system; [Figure 22] 4 is an explanatory diagram showing an example of the installation positions of an outside-vehicle information detection unit and an imaging unit; FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] Next, a mode for carrying out the present disclosure (hereinafter, referred to as an embodiment) will be described with reference to the drawings. In the following drawings, the same or similar parts are given the same or similar reference numerals. The embodiment will be described in the following order. 1. First embodiment 2. Second embodiment 3. Third embodiment 4. Fourth embodiment 5. Fifth embodiment 6. Sixth embodiment 7. Seventh embodiment 8. Camera application example 9. Application example to endoscopic surgery system 10. Mobile Applications

[0022] <1. First embodiment> [Image sensor configuration] 1 is a diagram showing an example of the configuration of an image sensor according to an embodiment of the present disclosure, the image sensor 1 in the figure includes a pixel array section 2, a vertical drive section 3, a column signal processing section 4, and a control section 5.

[0023] The pixel array section 2 is configured by arranging the pixels 100 and the phase difference pixels 200 in a two-dimensional lattice. Here, the pixel 100 generates an image signal according to the irradiated light. The pixel 100 has a photoelectric conversion section that generates an electric charge according to the irradiated light. The pixel 100 further has a pixel circuit. The pixel circuit generates an image signal based on the electric charge generated by the photoelectric conversion section. The generation of the image signal is controlled by a control signal generated by a vertical driving section 3 described later. In the pixel array section 2, signal lines 6 and 7 are arranged in an XY matrix. The signal line 6 is a signal line that transmits a control signal for the pixel circuit in the pixel 100, is arranged for each row of the pixel array section 2, and is commonly wired to the pixels 100 arranged in each row. The signal line 7 is a signal line that transmits an image signal generated by the pixel circuit of the pixel 100, is arranged for each column of the pixel array section 2, and is commonly wired to the pixels 100 arranged in each column. These photoelectric conversion sections and pixel circuits are formed on a semiconductor substrate.

[0024] Moreover, the phase difference pixel 200 is a pixel that detects the phase difference of the object. The hatched rectangle of the pixel array unit 2 in the figure represents the phase difference pixel 200. The phase difference pixel 200 is arranged in pairs of two adjacent phase difference pixels 200, and performs pupil division. Like the pixel 100, the phase difference pixel 200 also has a photoelectric conversion unit and a pixel circuit arranged therein, and signal lines 6 and 7 are connected thereto.

[0025] The vertical driving unit 3 generates control signals for the pixel circuits of the pixels 100 and the phase difference pixels 200. The vertical driving unit 3 transmits the generated control signals to the pixels 100 via a signal line 6 in the figure. The column signal processing unit 4 processes image signals generated by the pixels 100 and the phase difference pixels 200. The column signal processing unit 4 processes image signals transmitted from the pixels 100 via a signal line 7 in the figure. The processing in the column signal processing unit 4 corresponds to, for example, analog-to-digital conversion that converts analog image signals generated in the pixels 100 and the phase difference pixels 200 into digital image signals. The image signals processed by the column signal processing unit 4 are output as image signals for the image sensor 1. The control unit 5 controls the entire image sensor 1. The control unit 5 controls the image sensor 1 by generating and outputting control signals that control the vertical driving unit 3 and the column signal processing unit 4. The control signals generated by the control unit 5 are transmitted to the vertical driving unit 3 and the column signal processing unit 4 via signal lines 8 and 9, respectively. The column signal processing unit 4 is an example of a processing circuit described in the claims.

[0026] [Pixel circuit configuration] 2 is a circuit diagram showing a configuration example of a pixel according to the first embodiment of the present disclosure. The figure is a circuit diagram showing a configuration example of a pixel 100. The pixel 100 in the figure includes a photoelectric conversion unit 11, a charge transfer unit 12, a charge holding unit 21, and MOS transistors 22 to 24. In the figure, the charge transfer unit 12 is assumed to be a MOS transistor.

[0027] The anode of the photoelectric conversion unit 11 is grounded, and the cathode is connected to the source of the charge transfer unit 12. The drain of the charge transfer unit 12 is connected to the source of the MOS transistor 22, the gate of the MOS transistor 23, and one end of the charge holding unit 21. The other end of the charge holding unit 21 is grounded. The drains of the MOS transistors 22 and 23 are commonly connected to a power supply line Vdd, and the source of the MOS transistor 23 is connected to the drain of the MOS transistor 24. The source of the MOS transistor 24 is connected to a signal line 7. The gates of the charge transfer unit 12 and the MOS transistors 22 and 24 are connected to a transfer signal line TR, a reset signal line RST, and a selection signal line SEL, respectively. The transfer signal line TR, the reset signal line RST, and the selection signal line SEL form a signal line 6.

[0028] As described above, the photoelectric conversion unit 11 generates electric charges according to irradiated light. A photodiode can be used for this photoelectric conversion unit 11. The charge holding unit 21 and the MOS transistors 22 to 24 constitute a pixel circuit 20.

[0029] The charge transfer unit 12 is a transistor that transfers charges generated by photoelectric conversion in the photoelectric conversion unit 11 to the charge holding unit 21. The transfer of charges in the charge transfer unit 12 is controlled by a signal transmitted by a transfer signal line TR. The charge holding unit 21 is a capacitor that holds the charges transferred by the charge transfer unit 12. The MOS transistor 23 is a transistor that generates a signal based on the charges held in the charge holding unit 21. The MOS transistor 24 is a transistor that outputs the signal generated by the MOS transistor 23 to the signal line 7 as an image signal. This MOS transistor 24 is controlled by a signal transmitted by a selection signal line SEL.

[0030] The MOS transistor 22 is a transistor that resets the charge holding unit 21 by discharging the charge held in the charge holding unit 21 to the power supply line Vdd. This reset by the MOS transistor 22 is controlled by a signal transmitted by a reset signal line RST, and is executed before the charge is transferred by the charge transfer unit 12. Note that during this reset, the photoelectric conversion unit 11 can also be reset by making the charge transfer unit 12 conductive. In this way, the pixel circuit 20 converts the charge generated by the photoelectric conversion unit 11 into an image signal.

[0031] The pixel circuit 20 is a circuit that generates an image signal based on charges generated by the photoelectric conversion unit 11 and transferred by the charge transfer unit 12. The circuit configuration in the same figure can also be applied to the phase difference pixel 200.

[0032] [Pixel configuration] 3 is a cross-sectional view showing a configuration example of a pixel according to the first embodiment of the present disclosure. The figure is a schematic cross-sectional view showing a configuration example of a pixel 100. The pixel 100 in the figure includes a semiconductor substrate 110, a wiring region 130, a fixed charge film 141, a separator 142, a light-shielding film 143, a color filter 150, a planarization film 144, and an on-chip lens 181.

[0033] The semiconductor substrate 110 is a semiconductor substrate on which the photoelectric conversion unit 11 of the pixel 100, the diffusion region of the element of the pixel circuit 20, etc. are formed. This semiconductor substrate 110 can be made of, for example, silicon (Si). The diffusion region of the element of the photoelectric conversion unit 11 and the pixel circuit 20 is disposed in a well region formed in the semiconductor substrate 110. For convenience, it is assumed that the semiconductor substrate 110 in the figure is configured in a p-type well region. By disposing an n-type semiconductor region in the semiconductor substrate 110, which is the p-type well region, the photoelectric conversion unit 11, etc. can be formed. The rectangle inside the semiconductor substrate 110 represents the n-type semiconductor region. A wiring region 130, which will be described later, is formed on the front surface side of the semiconductor substrate 110.

[0034] The photoelectric conversion unit 11 is composed of an n-type semiconductor region 111. Specifically, the photoelectric conversion unit 11 corresponds to a photodiode composed of a pn junction at the interface between the n-type semiconductor region 111 and a surrounding p-type well region. When incident light is irradiated, photoelectric conversion occurs in the n-type semiconductor region 111. Of the charges generated by this photoelectric conversion, electrons are accumulated in the n-type semiconductor region 111. The n-type semiconductor region 111 is disposed on the back side of the semiconductor substrate 110, and performs photoelectric conversion of the incident light irradiated to the back side. Such an imaging element 1 is called a back-illuminated imaging element.

[0035] N-type semiconductor regions 112 to 115 are formed on the front surface side of the semiconductor substrate 110. Gate electrodes 122 to 124 are arranged on the front surface of the semiconductor substrate 110 via a gate insulating film. These constitute MOS transistors 22 to 24 and a charge holding unit 21, and thus constitute the pixel circuit 20.

[0036] The n-type semiconductor region 112 is a semiconductor region that constitutes the charge holding unit 21. This n-type semiconductor region 112 is called a floating diffusion region, and holds the charges transferred by the charge transfer unit 12. The n-type semiconductor region 112, the n-type semiconductor region 113, and the gate electrode 122 constitute the MOS transistor 22. The n-type semiconductor regions 112 and 113 correspond to the source and drain of the MOS transistor 22, respectively. A well region in the vicinity of the gate electrode 122 between the n-type semiconductor regions 112 and 113 corresponds to the channel region of the MOS transistor 22.

[0037] Moreover, the n-type semiconductor region 113, the n-type semiconductor region 114, and the gate electrode 123 constitute a MOS transistor 23. The n-type semiconductor regions 113 and 114 correspond to the drain and source of the MOS transistor 23, respectively. Moreover, the n-type semiconductor region 114, the n-type semiconductor region 115, and the gate electrode 124 constitute a MOS transistor 24. The n-type semiconductor regions 114 and 115 correspond to the drain and source of the MOS transistor 24, respectively.

[0038] The charge transfer section 12 is a MOS transistor composed of an n-type semiconductor region 111, an n-type semiconductor region 112, and a gate electrode 121. The n-type semiconductor regions 111 and 112 correspond to the source and drain of the charge transfer section 12, respectively. The gate electrode 121 is configured in a shape in which an electrode is embedded in a hole formed in the semiconductor substrate 110 via a gate insulating film, and is disposed in the vicinity of the n-type semiconductor regions 111 and 112. By applying a gate voltage to the gate electrode 121, a channel is formed in a well region in the vicinity of the gate electrode 121, and the n-type semiconductor regions 111 and 112 are brought into a conductive state. As a result, the charge accumulated in the n-type semiconductor region 111 of the photoelectric conversion section 11 is transferred to the n-type semiconductor region 112, which is a floating diffusion. A transistor that transfers charges in a direction perpendicular to the semiconductor substrate 110 in this way is called a vertical transistor. The gate insulating film is, for example, silicon oxide (SiO 2 The gate electrode 121 may be made of, for example, a metal or polysilicon.

[0039] The wiring region 130 is disposed adjacent to the front surface side of the semiconductor substrate 110, and is a region where wiring for elements formed on the semiconductor substrate 110 is formed. An insulating layer 131 and a wiring layer 132 are disposed in the wiring region 130. The wiring layer 132 is made of a metal such as copper (Cu), and is wiring that transmits signals to the elements formed on the semiconductor substrate 110. The insulating layer 131 insulates the wiring layer 132. This insulating layer 131 is made of, for example, SiO 2 The insulating layer 131 and the wiring layer 132 can be configured in a multi-layer structure. In the figure, the insulating layer 131 between the gate electrodes 122 to 124 and the semiconductor substrate 110 is called a gate oxide film. The wiring layer 132 and the semiconductor region and the gate electrodes 12 3 etc. are connected by contact plugs 133.

[0040] The fixed charge film 141 is formed on the interface on the back side of the semiconductor substrate 110, and pins the interface state of the semiconductor substrate 110. This fixed charge film 141 is made of a material having a negative fixed charge, and accumulates holes in the vicinity of the interface of the semiconductor substrate 110. The interface state is pinned by these accumulated holes. This makes it possible to reduce the influence of dark current caused by the interface state.

[0041] The separation portion 142 is disposed in the form of a wall surrounding the semiconductor substrate 110 of the pixel 100, and separates the semiconductor substrate 110. The separation portion 142 also blocks incident light from the adjacent pixel 100. This separation portion 142 can be configured by disposing a metal such as tungsten (W) in a groove formed in the semiconductor substrate 110. The separation portion 142 in the figure is disposed in a groove formed in the semiconductor substrate 110 via a fixed charge film 141.

[0042] The light-shielding film 143 is disposed on the back surface side of the semiconductor substrate 110 to block incident light. This light-shielding film is disposed on the boundary between the pixels 100 to block light transmitted through the color filters 150 of the adjacent pixels 100. This makes it possible to prevent color mixing. The light-shielding film 143, like the separation portion 142, can be made of a metal such as W.

[0043] The color filter 150 is an optical filter that transmits light of a predetermined wavelength from the incident light. For example, color filters 150 that transmit red light, green light, and blue light can be arranged in the pixel 100. Also, a color filter 150 that transmits infrared light can be arranged in the pixel 100.

[0044] The planarization film 144 is a film that planarizes the back surface side of the pixel 100 on which the color filter 150 is formed. This planarization film 144 can be made of a coating type insulating material.

[0045] The on-chip lens 181 is a lens that collects incident light. The on-chip lens 181 is configured in a hemispherical shape and collects incident light on the photoelectric conversion unit 11 (n-type semiconductor region 111) of the semiconductor substrate 110. The on-chip lens 181 in the figure collects incident light via a color filter 150. The on-chip lens 181 can be made of, for example, an organic material with a refractive index of 1.0 to 1.3. The on-chip lens 181 is an example of an individual on-chip lens described in the claims.

[0046] In addition, in the phase detection pixel 200, a common on-chip lens 182 described later is arranged instead of the on-chip lens 181. Other than this, the configuration of the phase detection pixel 200 can be the same as that of the pixel 100.

[0047] [Pixel array configuration] 4 is a diagram showing a configuration example of a pixel array section according to the first embodiment of the present disclosure. The figure is a plan view showing a configuration example of a pixel 100 and a phase difference pixel 200 in the pixel array section 2. Break The line rectangle represents pixel 100, point The lined rectangle represents the phase difference pixel 200. In addition, in the pixel 100 and the phase difference pixel 200, the rectangle with diagonal hatching represents the region of the pixel circuit 20. The rectangle in the pixel circuit 20 represents the n-type semiconductor region 112 of the charge holding unit 21. In addition, the rectangle with cross-hatching represents the gate electrode 121 of the vertical transistor. The rectangle adjacent to the pixel circuit 20 and the gate electrode 121 represents the n-type semiconductor region 111 of the photoelectric conversion unit 11. The gate electrode 121 of the charge transfer unit 12 is disposed at a corner of the pixel 100, etc., and the n-type semiconductor region 111 and the pixel circuit 20 are disposed adjacent to each other.

[0048] The dashed-dotted circle of the pixel 100 represents the on-chip lens 181. The dashed-dotted oval of the phase detection pixel 200 represents the common on-chip lens 182. As shown in the figure, the on-chip lens 181 is disposed for each pixel 100, and the common on-chip lens 182 is disposed in common to two adjacent phase detection pixels 200. The shape of the common on-chip lens 182 is not limited to this example. For example, the common on-chip lens 182 may be configured to have an elliptical shape. The two adjacent phase detection pixels 200 in the figure perform pupil division in the adjoining direction. In the pixel array unit 2 in the figure, the subject is pupil-divided into left and right.

[0049] The charge of the n-type semiconductor region 111 of the photoelectric conversion unit 11 is transferred by changing the direction by 90 degrees in a plan view by the charge transfer unit 12 configured as a vertical transistor. This charge transfer unit 12 is arranged in a region that does not overlap with the common on-chip lens 182 in the phase difference pixel 200. That is, the charge transfer unit 12 configured as a vertical transistor having a gate electrode 121 that does not contribute to photoelectric conversion is arranged in a region between the common on-chip lens 182 and the on-chip lens 181 on the surface where the incident light is irradiated. This makes it possible to eliminate the influence of the charge transfer unit 12 on the collection of incident light by the common on-chip lens 182 in the phase difference pixel 200. This is because the gate electrode 121 of the charge transfer unit 12 does not block the optical path of the incident light collected by the common on-chip lens 182.

[0050] [Phase detection pixel configuration] 5 is a cross-sectional view showing a configuration example of a phase difference pixel according to the first embodiment of the present disclosure. The drawing is a cross-sectional view showing a configuration example of a phase difference pixel 200, and is a cross-sectional view taken along line a-a' in FIG.

[0051] As described above, the common on-chip lens 182 is disposed as a common on-chip lens for the two phase difference pixels 200. In addition, the common on-chip lens 182 forms a focal point in the vicinity of the back surface of the semiconductor substrate 110 between the two phase difference pixels 200. As a result, incident light from the subject that has passed through the left side of the photographing lens is incident on the photoelectric conversion unit 11 (n-type semiconductor region 111) of the right phase difference pixel 200, and incident light that has passed through the right side of the photographing lens is incident on the photoelectric conversion unit 11 of the left phase difference pixel 200. The solid arrow in the figure represents incident light 301 that has passed through the left side of the photographing lens, and the dotted arrow represents incident light 302 that has passed through the right side of the photographing lens. In this way, by disposing the common on-chip lens 182 in two adjacent phase difference pixels 200, pupil division can be performed, and phase difference detection becomes possible.

[0052] In addition, light from a subject that passes through a focal point near the back surface of the semiconductor substrate 110 between the two phase difference pixels 200 is incident on the n-type semiconductor region 111 and photoelectrically converted. If a structure that does not contribute to photoelectric conversion, such as the gate electrode 121 of the charge transfer unit 12, is arranged near the n-type semiconductor region 111 where the incident light reaches, the photoelectric conversion of the incident light is hindered. In addition, if such a structure is arranged asymmetrically in the two phase difference pixels 200, a difference occurs in the sensitivity of the two phase difference pixels 200, resulting in a difference in image signal output. Since a difference in image signals that is not caused by the phase difference of the incident light occurs, an error in phase difference detection occurs.

[0053] Even when a structure that does not contribute to photoelectric conversion is arranged near the photoelectric conversion unit 11, it is thought that the difference in image signals will not occur by configuring the two phase difference pixels 200 to be completely symmetrical. However, it is difficult to configure the two phase difference pixels 200 to be completely symmetrical. In addition, in the phase difference pixels 200 arranged in the peripheral portion of the pixel array unit 2, the image height becomes high and incident light is obliquely incident on the phase difference pixel 200. For this reason, the influence of the structure that does not contribute to photoelectric conversion increases. Therefore, as described above in FIG. 4, the charge transfer unit 12 having the gate electrode 121, which is a structure that does not contribute to photoelectric conversion, is arranged in a region different from the region where the common on-chip lens 182 is arranged. This makes it possible to reduce the output difference of the image signals of the two phase difference pixels 200. Even in this case, it is possible to further reduce the output difference of the image signals of the two phase difference pixels 200 by configuring the two phase difference pixels 200 to be symmetrical.

[0054] As described above, the image sensor 1 according to the first embodiment of the present disclosure includes two phase difference pixels 200 in which the common on-chip lens 182 is disposed. In the image sensor 1 according to the first embodiment of the present disclosure, the charge transfer unit 12 having the gate electrode 121, which is a structure that does not contribute to photoelectric conversion, is disposed between the common on-chip lens 182 and the on-chip lens 181 of the pixel 100. This makes it possible to reduce a difference in image signals between the phase difference pixels 200, and to reduce an error in phase difference detection by the phase difference pixels 200.

[0055] <2. Second embodiment> In the image sensor 1 according to the first embodiment described above, two phase detection pixels 200 are arranged adjacent to each other. In contrast, the image sensor 1 according to the second embodiment of the present disclosure differs from the image sensor 1 according to the first embodiment described above in that a separation unit is arranged on the semiconductor substrate 110 between two adjacent phase detection pixels 200.

[0056] [Phase detection pixel configuration] Fig. 6 is a cross-sectional view showing a configuration example of a phase difference pixel according to a second embodiment of the present disclosure. The same figure is a cross-sectional view showing a configuration example of a phase difference pixel 200, similar to Fig. 5. It differs from the phase difference pixel 200 described in Fig. 5 in that a separation unit 142 is arranged on the semiconductor substrate 110 between two phase difference pixels 200.

[0057] In the phase difference pixel 200 in the same figure, the separation portion 142 is arranged in a well region between each of the n-type semiconductor regions 111 of the semiconductor substrate 110. Therefore, leakage of incident light and leakage of charges from adjacent phase difference pixels 200 can be reduced.

[0058] Other than this, the configuration of the imaging element 1 is similar to the configuration of the imaging element 1 described in the first embodiment of the present disclosure, and therefore a description thereof will be omitted.

[0059] As described above, the image sensor 1 according to the second embodiment of the present disclosure can reduce leakage of incident light and the like and reduce the occurrence of differences in image signals by disposing the separation unit 142 on the semiconductor substrate 110 between the two phase difference pixels 200. Errors in phase difference detection can be further reduced.

[0060] <3. Third embodiment> In the image sensor 1 according to the first embodiment described above, a pixel circuit 20 is arranged for each pixel 100 and each phase difference pixel 200. In contrast, the image sensor 1 according to the third embodiment of the present disclosure differs from the image sensor 1 according to the first embodiment described above in that the pixel circuit 20 is shared by a plurality of pixels 100 or the like.

[0061] [Pixel circuit configuration] 7 is a circuit diagram showing a configuration example of a pixel according to the third embodiment of the present disclosure. The pixel 100 and the phase difference pixel 200 in the figure are different from the pixel 100 and the phase difference pixel 200 described in FIG. 2 in that the pixel circuit 20 is shared among a plurality of pixels 100, etc. The circuit configuration will be described taking the pixel 100 as an example. The pixel 100 in the figure includes a photoelectric conversion unit 11 and a charge transfer unit 12, and the pixel circuit 20 is arranged separately. The figure shows an example in which the pixel circuit 20 is commonly connected to four pixels 100, etc. (pixels 100a, 100b, and 100c, and the phase difference pixel 200a).

[0062] The drains of the charge transfer units 12 of the pixels 100a, 100b, and 100c and the phase difference pixel 200a are commonly connected to a charge holding unit 21 of the pixel circuit 20.

[0063] By sequentially inputting ON signals to the TRs of the pixels 100a, 100b, and 100c and the phase difference pixel 200a, the charges generated by the photoelectric conversion units 11 of the pixels 100a and the like are sequentially transferred to the pixel circuit 20. Image signals can be sequentially generated based on the transferred charges.

[0064] [Pixel configuration] FIG. 8 is a cross-sectional view showing a configuration example of a pixel according to the third embodiment of the present disclosure. This figure is a schematic cross-sectional view showing a configuration example of a pixel 100, similar to FIG. 3. In addition, the letters "a" and "b" attached to the reference numerals in this figure correspond to different pixels 100 (pixels 100a and b) shown in FIG. 7. The pixel 100 in this figure differs from the pixel 100 described in FIG. 3 in the following points. A charge holding section 21 is disposed between the pixels 100, etc. In addition, a plurality of charge transfer sections 12 (charge transfer sections 12a and 12b) are commonly connected to the charge holding section 21. That is, the gate electrodes 121a and 121b of the charge transfer sections 12a and 12b are disposed adjacent to the n-type semiconductor region 112 of the charge holding section 21. The n-type semiconductor region 112 of the charge holding section 21 constitutes a common drain region of the charge transfer sections 12a and 12b. In addition, the pixel circuit 20 other than the charge holding section 21 is omitted.

[0065] [Pixel array configuration] 9 is a diagram showing a configuration example of a pixel array section according to a third embodiment of the present disclosure. The figure is a plan view showing a configuration example of the pixel 100 and the phase difference pixel 200 in the pixel array section 2, similar to FIG. 4. The pixel array section 2 differs from the pixel array section 2 described in FIG. 4 in that the pixel circuit 20 is arranged in an outer region of the pixel 100, etc., and is arranged in common for each of the multiple pixels 100.

[0066] The pixel circuit 20 is disposed in common for adjacent two rows and two columns of pixels 100, etc. The n-type semiconductor region 112 of the charge holding unit 21 of the pixel circuit 20 is disposed in the center of these four pixels 100, etc. The gate electrodes 121 of the four pixels 100, etc. are disposed adjacent to the n-type semiconductor region 112 of the charge holding unit 21.

[0067] In this figure, the gate electrode 121 is also disposed between the common on-chip lens 182 and the on-chip lens 181. This makes it possible to reduce the output difference between the image signals of the two phase difference pixels 200.

[0068] Other than this, the configuration of the imaging element 1 is similar to the configuration of the imaging element 1 described in the first embodiment of the present disclosure, and therefore a description thereof will be omitted.

[0069] As described above, in the imaging element 1 according to the third embodiment of the present disclosure, the pixel circuit 20 is shared by a plurality of pixels 100 etc. This can simplify the configuration of the pixels 100 etc.

[0070] <4. Fourth embodiment> In the image sensor 1 according to the third embodiment described above, the photoelectric conversion unit 11 is disposed on the semiconductor substrate 110 of the pixel 100 and the phase difference pixel 200. In contrast, the image sensor 1 according to the fourth embodiment of the present disclosure differs from the image sensor 1 according to the first embodiment described above in that a photoelectric conversion film that performs photoelectric conversion is further disposed.

[0071] [Pixel circuit configuration] FIG. 10 is a circuit diagram showing a configuration example of a pixel according to a fourth embodiment of the present disclosure. The pixel 100 and the phase difference pixel 200 in the figure are different from the pixel 100 and the phase difference pixel 200 described in FIG. 7 in that a photoelectric conversion unit is further arranged and a plurality of pixel circuits 20 are shared among a plurality of pixels 100, etc. The circuit configuration will be described by taking the pixel 100 as an example. The pixel 100 in the figure further includes a photoelectric conversion unit 13 and a switch element 14, and a plurality of pixel circuits 20 are arranged. The figure shows an example in which two pixel circuits 20 (pixel circuits 20a and 20b) are commonly connected to four pixels 100, etc. (pixels 100a, 100b, and 100c and a phase difference pixel 200a).

[0072] The photoelectric conversion unit 13 is a photoelectric conversion unit configured by sandwiching a photoelectric conversion film between a first electrode and a second electrode. In the figure, the photoelectric conversion unit 13 is configured as a two-terminal element and generates charges based on photoelectric conversion. Also, the switch element 14 is an element that transfers the charges generated by the photoelectric conversion unit 13, similar to the charge transfer unit 12. The switch element 14 is configured as a three-terminal element and has an input terminal, an output terminal, and a control signal terminal. Like the MOS transistor of the charge transfer unit 12, when a control signal is input to the control signal terminal, a conductive state is established between the input terminal and the output terminal. As will be described later, the photoelectric conversion unit 13 and the switch element 14 are configured integrally in the pixel 100, etc. In the figure, the photoelectric conversion unit 13 and the switch element 14 are individually illustrated for convenience. Also, a power supply line Vou is further arranged in the pixel 100, etc. in the figure. This power supply line Vou is a power supply line that supplies a bias voltage to the photoelectric conversion unit 13. The signal line 6 further includes a signal line TR2 that transmits a control signal to the control signal terminal of the switch element 14. Accordingly, the signal line that transmits a control signal to the gate of the charge transfer unit 12 is changed to a signal line TR1 for distinction.

[0073] The drains of the charge transfer units 12 of the pixels 100a, 100b, and 100c and the phase difference pixel 200a are commonly connected to the charge holding unit 21 of the pixel circuit 20a. In addition, one end of the photoelectric conversion unit 13 is connected to a power supply line Vou, and the other end is connected to an input terminal of the switch element 14. A control signal terminal of the switch element 14 is connected to a signal line TR2. The output terminals of the switch element 14 of the pixels 100a, 100b, and 100c and the phase difference pixel 200a are commonly connected to the charge holding unit 21 of the pixel circuit 20b.

[0074] By sequentially inputting ON signals to TR1 of each of the pixels 100a, 100b, and 100c and the phase difference pixel 200a, the charges generated by the photoelectric conversion unit 11 of the pixel 100a and the like are sequentially transferred to the pixel circuit 20a to generate an image signal. Similarly, by sequentially inputting control signals to TR2 of each of the pixels 100a, 100b, and 100c and the phase difference pixel 200a, the charges generated by the photoelectric conversion unit 13 of the pixel 100a and the like are sequentially transferred to the pixel circuit 20b to generate an image signal.

[0075] [Pixel configuration] FIG. 11 is a cross-sectional view showing a configuration example of a pixel according to the fourth embodiment of the present disclosure. This is a schematic cross-sectional view showing a configuration example of a pixel 100, similar to FIG. 8. In addition, the letters "a", "b" and "c" attached to the reference symbols in this figure correspond to different pixels 100 (pixels 100a, 100b and 100c) shown in FIG. 10. The pixel 100 in this figure differs from the pixel 100 described in FIG. 8 in the following respects. The charge transfer section 12 is composed of a MOS transistor. In addition, a plurality of charge transfer sections 12 (charge transfer sections 12a and 12b) are commonly connected to the charge retention section 21a. That is, the n-type semiconductor region 112 of the charge retention section 21a constitutes a common drain region of the charge transfer sections 12a and 12b. The gate electrodes 125a and 125b in this figure correspond to the gates of these charge transfer sections 12. The charge retention section 21a corresponds to the charge retention section 21 of the pixel circuit 20a described in FIG. 10. The semiconductor device further includes a photoelectric conversion unit 19, and a through electrode 139 that transfers charges generated by the photoelectric conversion unit 19. A high refractive index film 151 is disposed between the photoelectric conversion unit 19 and the on-chip lens 181.

[0076] The photoelectric conversion unit 19 is disposed adjacent to the rear surface side of the semiconductor substrate 110. Specifically, it is disposed in the region of the planarization film 144. The photoelectric conversion unit 19 includes a first electrode 163, an insulating film 162, a photoelectric conversion film 164, a second electrode 165, and a charge storage electrode 161. The photoelectric conversion unit 19 is configured by laminating the charge storage electrode 161, the insulating film 162, the photoelectric conversion film 164, and the second electrode 165. The first electrode 163, the photoelectric conversion film 164, and the second electrode 165 are commonly disposed in a plurality of pixels 100, and the charge storage electrode 161 and the insulating film 162 are individually disposed in the pixels 100, etc. In addition, the first electrode 163 is connected to the center of the photoelectric conversion film 164 commonly disposed in a plurality of pixels 100. The insulating film 162 can also be commonly disposed in a plurality of pixels 100, etc.

[0077] The photoelectric conversion film 164 is made of an organic photoelectric conversion film and performs photoelectric conversion of incident light. The photoelectric conversion film 164 can be made of an organic photoelectric conversion material including, for example, rhodamine-based dyes, melacyanine-based dyes, quinacridone, phthalocyanine-based dyes, coumarin-based dyes, and tris-8-hydroxyquinoline Al. The photoelectric conversion film 164 can be configured to absorb light of a specific wavelength among the incident light and perform photoelectric conversion.

[0078] The second electrode 165 is an electrode disposed adjacent to the photoelectric conversion film 164. The second electrode 165 can be made of, for example, indium tin oxide (ITO). The insulating film 162 is a film that provides insulation between the photoelectric conversion film 164 and the charge storage electrode 161. The insulating film 162 can be made of, for example, SiO 2 The first electrode 163 is an electrode that is laminated on the photoelectric conversion film 164 via an insulating film 162 and applies a voltage to the photoelectric conversion film 164. The charge storage electrode 161 can be made of, for example, ITO. The first electrode 163 is an electrode that outputs the charge generated by the photoelectric conversion film 164.

[0079] The second electrode 165 and the photoelectric conversion film 164 correspond to the photoelectric conversion unit 13 described with reference to Fig. 10. The insulating film 162, the charge storage electrode 161, and the first electrode 163 correspond to the switch element 14 described with reference to Fig. 10.

[0080] 10. The first electrode 163 corresponds to the output terminal of the switch element 14 in FIG. 10. The charge storage electrode 161 corresponds to the control signal terminal of the switch element 14. The charge storage electrode 161 and the first electrode 163 are connected to wirings 168 and 169, respectively.

[0081] During an exposure period of the imaging element, a control signal with a voltage higher than the voltage of the power supply line Vou is applied to the charge storage electrode 161. Then, electrons of the charges generated by photoelectric conversion of the photoelectric conversion film 164 are attracted to the charge storage electrode 161 and stored in a region of the photoelectric conversion film 164 near the charge storage electrode 161 via the insulating film 162. Thereafter, when transferring the charges generated by photoelectric conversion, a control signal with a voltage lower than the voltage of the power supply line Vou is applied to the charge storage electrode 161. As a result, the charges (electrons) stored in the photoelectric conversion film 164 move to the first electrode 163 and are output from the wiring 169.

[0082] The through electrode 139 is an electrode that penetrates the semiconductor substrate 110. The through electrode 139 is an electrode that transfers charges from the back side to the front side of the semiconductor substrate 110. The through electrode 139 can be formed, for example, by embedding a conductive material such as a metal in a through hole formed in the semiconductor substrate 110. The through electrode 139 in the figure connects between the wiring 169 of the photoelectric conversion unit 19 and the wiring layer 132 arranged in the wiring region 130. The charge generated by the above-mentioned photoelectric conversion unit 19 and moved to the first electrode 163 is transferred to the front side of the semiconductor substrate 110 via the through electrode 139. The transferred charge is further transferred to the n-type semiconductor region 116 via the wiring layer 132 and the contact plug 133. The n-type semiconductor region 116 constitutes the charge holding unit 21b of the pixel circuit 20b described in FIG. 10.

[0083] The high refractive index film 151 is a film configured to have a high refractive index. The photoelectric conversion unit 19 is disposed close to the on-chip lens 181. By disposing this high refractive index film 151, the focusing position of incident light can be brought closer to the photoelectric conversion unit 19. For example, silicon nitride (SiN) can be used for the high refractive index film 151. It is also possible to omit the high refractive index film 151.

[0084] Since the photoelectric conversion unit 19 is disposed between the on-chip lens 181 and the semiconductor substrate 110, light of a wavelength not absorbed by the photoelectric conversion unit 19 is photoelectrically converted by the photoelectric conversion unit 11 of the semiconductor substrate 110. For example, a configuration may be adopted in which the photoelectric conversion unit 19 performs photoelectric conversion of visible light, and the photoelectric conversion unit 11 performs photoelectric conversion of infrared light. Also, for example, a configuration may be adopted in which the photoelectric conversion unit 19 performs photoelectric conversion of short-wavelength visible light, and the photoelectric conversion unit 11 performs photoelectric conversion of long-wavelength visible light.

[0085] [Pixel array configuration] Fig. 12 is a diagram showing a configuration example of a pixel array section according to a fourth embodiment of the present disclosure. The figure is a plan view showing a configuration example of the pixel 100 and the phase difference pixel 200 in the pixel array section 2, similar to Fig. 4. This differs from the pixel array section 2 described in Fig. 4 in that the pixel circuits 20a and 20b are arranged in an outer region of the pixel 100, etc., and are arranged in common for a plurality of pixels 100, and a through electrode 139 is further arranged.

[0086] The pixel circuit 20a is arranged in common to the adjacent pixels 100 of two rows and two columns. The n-type semiconductor region 112 of the charge holding unit 21 of the pixel circuit 20a is arranged in the center of these four pixels 100. Similarly, the pixel circuit 20b is arranged in common to the adjacent pixels 100 of two rows and two columns. The through electrode 139 connected to the pixel circuit 20b is arranged in the center of these four pixels 100.

[0087] In the figure, the through electrode 139 is disposed between the common on-chip lens 182 and the on-chip lens 181. The through electrode 139 corresponds to a structure disposed on the semiconductor substrate 110 and does not contribute to photoelectric conversion. By disposing this through electrode 139 in a region different from the region where the common on-chip lens 182 is disposed, it is possible to reduce the output difference of the image signals of the two phase difference pixels 200.

[0088] The configuration of the pixel 100 is not limited to this example. For example, the photoelectric conversion unit using the photoelectric conversion film can be a two-terminal type in which the charge storage electrode 161 is omitted. Even in this case, the through electrode 139 is disposed between the common on-chip lens 182 and the on-chip lens 181.

[0089] Other than this, the configuration of the imaging element 1 is similar to the configuration of the imaging element 1 described in the first embodiment of the present disclosure, and therefore a description thereof will be omitted.

[0090] As described above, in the image sensor 1 according to the fourth embodiment of the present disclosure, the through electrode 139, which is a structure that does not contribute to photoelectric conversion, is disposed between the common on-chip lens 182 and the on-chip lens 181 of the pixel 100. This can reduce a difference in image signals of the phase difference pixels 200, and can reduce errors in phase difference detection of the phase difference pixels 200.

[0091] <5. Fifth embodiment> In the image sensor 1 according to the above-described fourth embodiment, the photoelectric conversion unit 19 including a photoelectric conversion film is disposed on the back surface side of the semiconductor substrate 110. In contrast, the image sensor 1 according to the fifth embodiment of the present disclosure differs from the above-described fourth embodiment in that a color filter is disposed between the on-chip lens and the photoelectric conversion unit 19.

[0092] [Pixel configuration] Fig. 13 is a cross-sectional view showing a configuration example of a pixel according to the fifth embodiment of the present disclosure. Similar to Fig. 11, the figure is a schematic cross-sectional view showing a configuration example of a pixel 100. The pixel 100 in the figure differs from the pixel 100 in Fig. 11 in that a color filter 150 is disposed between the second electrode 165 of the photoelectric conversion unit 19 and the high refractive index film 151.

[0093] For example, a color filter that blocks infrared light or ultraviolet light can be used as the color filter 150. This makes it possible to reduce errors caused by infrared light or the like in an image sensor that captures visible light.

[0094] Other than this, the configuration of the imaging element 1 is similar to the configuration of the imaging element 1 described in the fourth embodiment of the present disclosure, and therefore a description thereof will be omitted.

[0095] As described above, the image sensor 1 according to the fifth embodiment of the present disclosure can reduce errors in the visible light image signal by disposing the color filter 150 between the on-chip lens 181 and the photoelectric conversion unit 19.

[0096] <6. Sixth embodiment> In the image sensor 1 according to the above-described fifth embodiment, the color filter 150 is disposed between the on-chip lens 181 and the photoelectric conversion unit 19. In contrast, the image sensor 1 according to the sixth embodiment of the present disclosure differs from the above-described fifth embodiment in that a color filter is disposed between the photoelectric conversion unit 19 and the semiconductor substrate 110.

[0097] [Pixel configuration] Fig. 14 is a cross-sectional view showing a configuration example of a pixel according to the sixth embodiment of the present disclosure. Similar to Fig. 13, Fig. 14 is a schematic cross-sectional view showing a configuration example of a pixel 100. The pixel 100 in Fig. 14 differs from the pixel 100 in Fig. 13 in that a color filter 150 is disposed between the planarization film 144 and the fixed charge film 141.

[0098] The color filter 150 in the figure is disposed between the photoelectric conversion unit 19 and the semiconductor substrate 110, and light that has passed through the photoelectric conversion unit 19 is incident on the color filter 150 in the figure. Therefore, a color filter that blocks light of a wavelength that is not subject to photoelectric conversion in the photoelectric conversion unit 11 of the semiconductor substrate 110, among the light that is not absorbed by the photoelectric conversion unit 19, can be used. For example, when the photoelectric conversion unit 19 absorbs green light to perform photoelectric conversion, a color filter 150 that blocks the green light can be used. This can reduce errors in the image signal generated by the photoelectric conversion unit 11 of the semiconductor substrate 110.

[0099] Other than this, the configuration of the imaging element 1 is similar to the configuration of the imaging element 1 described in the fifth embodiment of the present disclosure, and therefore a description thereof will be omitted.

[0100] As described above, the imaging element 1 of the sixth embodiment of the present disclosure can reduce errors in the image signal generated in the photoelectric conversion section 11 of the semiconductor substrate 110 by disposing the color filter 150 between the photoelectric conversion section 19 and the semiconductor substrate 110.

[0101] <7. Seventh embodiment> In the imaging element 1 of the above-described fourth embodiment, the photoelectric conversion unit 11 is disposed on the semiconductor substrate 110. In contrast, the imaging element 1 of the seventh embodiment of the present disclosure differs from the above-described fourth embodiment in that it further includes a photoelectric conversion unit disposed on the semiconductor substrate 110.

[0102] [Pixel circuit configuration] Fig. 15 is a circuit diagram showing a configuration example of a pixel according to a seventh embodiment of the present disclosure. The pixel 100 and the phase difference pixel 200 in Fig. 15 are different from the pixel 100 and the phase difference pixel 200 described in Fig. 10 in that a photoelectric conversion unit is further arranged. The circuit configuration will be described taking the pixel 100 as an example. The pixel 100 in Fig. 15 is different from the pixel 100 described in Fig. 10 in that the pixel 100 in Fig. 15 further includes a photoelectric conversion unit 15 and a charge transfer unit 16, and further includes a pixel circuit 20c.

[0103] The photoelectric conversion unit 15 is configured with a photodiode formed on a semiconductor substrate 110, similar to the photoelectric conversion unit 11. The charge transfer unit 16 is configured with a MOS transistor, similar to the charge transfer unit 12. The signal line 6 further includes a signal line TR3 that transmits a control signal to the gate of the charge transfer unit 16.

[0104] The anode of the photoelectric conversion unit 15 is grounded, and the cathode is connected to the source of the charge transfer unit 16. The gate of the charge transfer unit 16 is connected to a signal line TR3. The drains of the charge transfer units 16 of the pixels 100a, 100b, and 100c and the phase difference pixel 200a are commonly connected to the charge holding unit 21 of the pixel circuit 20c.

[0105] [Pixel configuration] Fig. 16 is a cross-sectional view showing a configuration example of a pixel according to the seventh embodiment of the present disclosure. Similar to Fig. 11, Fig. 16 is a schematic cross-sectional view showing a configuration example of a pixel 100. The pixel 100 in Fig. 16 differs from the pixel 100 described in Fig. 11 in that it further includes a photoelectric conversion unit 15, a charge transfer unit 16, and a color filter 150.

[0106] The photoelectric conversion unit 15 is disposed near the back surface of the semiconductor substrate 110. Specifically, an n-type semiconductor region 117 constituting the photoelectric conversion unit 15 is formed in a shallow region on the back surface side of the semiconductor substrate 110. On the other hand, an n-type semiconductor region 111 of the photoelectric conversion unit 11 is formed in a deep region of the semiconductor substrate 110. That is, it is disposed near the front surface of the semiconductor substrate 110.

[0107] An n-type semiconductor region 118 disposed on the semiconductor substrate 110 is a semiconductor region that constitutes the charge holding unit 21c of the pixel circuit 20c.

[0108] The charge transfer section 16 is disposed adjacent to the n-type semiconductor region 117 of the photoelectric conversion section 15. This charge transfer section 16 is configured as a vertical transistor, similar to the charge transfer section 12 described in FIG. 3. The charge transfer section 16 includes a gate electrode 126. The charge transfer section 16 transfers charges generated by the photoelectric conversion section 15 disposed near the back surface of the semiconductor substrate 110 to the semiconductor region 118 of the charge retention section 21 disposed on the front surface side of the semiconductor substrate 110.

[0109] The photoelectric conversion unit 19 made of a photoelectric conversion film is disposed in a region closest to the on-chip lens 181, and can be configured to absorb light of a short wavelength, for example, blue light, and perform photoelectric conversion. The photoelectric conversion unit 15 is disposed in a shallow region from the back surface of the semiconductor substrate 110, and performs photoelectric conversion of light of a relatively short wavelength, for example, green light, among the incident light transmitted through the photoelectric conversion unit 19. In contrast, the photoelectric conversion unit 11 is disposed in a deep region from the back surface of the semiconductor substrate 110, and performs photoelectric conversion of light that reaches a deep region of the semiconductor substrate 110, such as red light or infrared light. In this way, the pixel 100 in the figure can perform photoelectric conversion of incident light in three wavelength ranges and generate image signals corresponding to each light.

[0110] A color filter that blocks ultraviolet light can be used as the color filter 150. When the above-mentioned photoelectric conversion unit 11 performs photoelectric conversion of only red light, a color filter 150 that blocks infrared light can be used.

[0111] [Pixel array configuration] Fig. 17 is a diagram showing a configuration example of a pixel array section according to a seventh embodiment of the present disclosure. The figure is a plan view showing a configuration example of the pixel 100 and the phase difference pixel 200 in the pixel array section 2, similar to Fig. 12. It differs from the pixel array section 2 described in Fig. 12 in that a pixel circuit 20c is further arranged and a gate electrode 126 is further arranged.

[0112] The pixel circuit 20a in the figure is disposed at a position shifted by one pixel from the pixel circuit 20a in Fig. 12. A pixel circuit 20c is disposed at the location where the pixel circuit 20a was disposed in Fig. 12. Four gate electrodes 126 are disposed adjacent to the n-type semiconductor region 118 of the charge retention portion of this pixel circuit 20c.

[0113] The charge holding units 21 of the pixel circuits 20a, 20b, and 20c are all commonly connected to the photoelectric conversion units 11 of the four pixels 100, etc.

[0114] As shown in the figure, the through electrode 139 and the gate electrode 126 (charge transfer unit 16) that do not contribute to photoelectric conversion are disposed in a region between the common on-chip lens 182 and the on-chip lens 181. Also, the charge holding units 21 of the pixel circuits 20a, 20b, and 20c are all shared and connected by four pixels 100, etc. This makes it possible to individually dispose the n-type semiconductor region 112, the through electrode 139, and the gate electrode 126 at the centers of the four pixels 100, etc. This makes it possible to reduce the output difference of the image signals of the two phase difference pixels 200.

[0115] Other than this, the configuration of the imaging element 1 is similar to the configuration of the imaging element 1 described in the fourth embodiment of the present disclosure, and therefore a description thereof will be omitted.

[0116] As described above, in the image sensor 1 according to the seventh embodiment of the present disclosure, the charge transfer unit 16 having the gate electrode 121, which is a structure that does not contribute to photoelectric conversion, and the through-electrode 139 are disposed between the common on-chip lens 182 and the on-chip lens 181 of the pixel 100. This can reduce a difference in image signals of the phase difference pixels 200, and can reduce errors in phase difference detection of the phase difference pixels 200.

[0117] The configuration of the phase detection pixel 200 according to the second embodiment may be combined with any of the third to seventh embodiments. That is, a separation unit 142 may be disposed in the semiconductor substrate 110 between the phase detection pixels 200 according to the third to seventh embodiments.

[0118] <8. Camera application example> The technology according to the present disclosure (the present technology) can be applied to various products. For example, the present technology may be realized as an imaging element mounted in an imaging device such as a camera.

[0119] 18 is a block diagram showing a schematic configuration example of a camera, which is an example of an imaging device to which the present technology can be applied. The camera 1000 in the figure includes a lens 1001, an imaging element 1002, an imaging control unit 1003, a lens driving unit 1004, an image processing unit 1005, an operation input unit 1006, a frame memory 1007, a display unit 1008, and a recording unit 1009.

[0120] A lens 1001 is a photographing lens of the camera 1000. This lens 1001 collects light from a subject and causes it to enter an image sensor 1002 (described later) to form an image of the subject.

[0121] The image sensor 1002 is a semiconductor element that captures an image of light from a subject collected by the lens 1001. The image sensor 1002 generates an analog image signal according to the irradiated light, converts it into a digital image signal, and outputs it.

[0122] The imaging control unit 1003 controls the imaging of the imaging element 1002. The imaging control unit 1003 controls the imaging element 1002 by generating a control signal and outputting it to the imaging element 1002. The imaging control unit 1003 can also perform autofocus in the camera 1000 based on an image signal output from the imaging element 1002. Here, autofocus is a system that detects the focal position of the lens 1001 and automatically adjusts it. As this autofocus, a method (image plane phase difference autofocus) can be used in which an image plane phase difference is detected by a phase difference pixel arranged in the imaging element 1002 to detect the focal position. Also, a method (contrast autofocus) can be applied in which a position where the contrast of an image is the highest is detected as the focal position. The imaging control unit 1003 adjusts the position of the lens 1001 via the lens driving unit 1004 based on the detected focal position, and performs autofocus. The imaging control unit 1003 can be configured, for example, by a DSP (Digital Signal Processor) equipped with firmware.

[0123] The lens driving unit 1004 drives the lens 1001 under the control of the imaging control unit 1003. The lens driving unit 1004 can drive the lens 1001 by changing the position of the lens 1001 using a built-in motor.

[0124] The image processing unit 1005 processes the image signal generated by the image sensor 1002. This processing includes, for example, demosaic for generating image signals of missing colors among the image signals corresponding to red, green, and blue for each pixel, noise reduction for removing noise from the image signal, and encoding of the image signal. The image processing unit 1005 can be configured, for example, by a microcomputer equipped with firmware.

[0125] The operation input unit 1006 receives an operation input from a user of the camera 1000. For example, a push button or a touch panel can be used for this operation input unit 1006. The operation input received by the operation input unit 1006 is transmitted to the imaging control unit 1003 and the image processing unit 1005. After that, a process according to the operation input, such as a process of capturing an image of a subject, is started.

[0126] The frame memory 1007 is a memory for storing frames, which are image signals for one screen. The frame memory 1007 is controlled by the image processing unit 1005, and holds frames during the image processing process.

[0127] The display unit 1008 displays the image processed by the image processing unit 1005. For this display unit 1008, for example, a liquid crystal panel can be used.

[0128] The recording unit 1009 records the image processed by the image processing unit 1005. For this recording unit 1009, for example, a memory card or a hard disk can be used.

[0129] The above describes a camera to which the present disclosure can be applied. The present technology can be applied to the imaging element 1002 among the configurations described above. Specifically, the imaging element 1 described in FIG. 1 can be applied to the imaging element 1002. By applying the imaging element 1 to the imaging element 1002, errors in phase difference detection can be reduced, and degradation of image quality during autofocus can be prevented. The camera 1000 is an example of an imaging device described in the claims. The image processing unit 1005 is an example of a processing circuit described in the claims.

[0130] Although a camera has been described as an example here, the technology according to the present disclosure may be applied to other devices, such as a monitoring device. The present disclosure may also be applied to a semiconductor device in the form of a semiconductor module, in addition to electronic devices such as a camera. Specifically, the technology according to the present disclosure may be applied to an imaging module, which is a semiconductor module in which the imaging element 1002 and the imaging control unit 1003 in FIG. 18 are enclosed in a single package.

[0131] <9. Application examples for endoscopic surgery systems> The technology according to the present disclosure may be applied to various products. For example, the technology according to the present disclosure may be applied to an endoscopic surgery system.

[0132] FIG. 19 is a diagram showing an example of a schematic configuration of an endoscopic surgery system to which the technology according to the present disclosure can be applied.

[0133] 19 shows a state in which an operator (doctor) 11131 is performing surgery on a patient 11132 on a patient bed 11133 using an endoscopic surgery system 11000. As shown in the figure, the endoscopic surgery system 11000 is composed of an endoscope 11100, other surgical tools 11110 such as an insufflation tube 11111 and an energy treatment tool 11112, a support arm device 11120 that supports the endoscope 11100, and a cart 11200 on which various devices for endoscopic surgery are mounted.

[0134] The endoscope 11100 is composed of a lens barrel 11101, a region of a predetermined length from the tip of which is inserted into a body cavity of a patient 11132, and a camera head 11102 connected to the base end of the lens barrel 11101. In the illustrated example, the endoscope 11100 is configured as a so-called rigid scope having a rigid lens barrel 11101, but the endoscope 11100 may be configured as a so-called flexible scope having a flexible lens barrel.

[0135] An opening into which an objective lens is fitted is provided at the tip of the lens barrel 11101. A light source device 11203 is connected to the endoscope 11100, and light generated by the light source device 11203 is guided to the tip of the lens barrel by a light guide extending inside the lens barrel 11101, and is irradiated via the objective lens toward an observation target in the body cavity of the patient 11132. The endoscope 11100 may be a direct-viewing endoscope, an oblique-viewing endoscope, or a side-viewing endoscope.

[0136] An optical system and an image sensor are provided inside the camera head 11102, and reflected light (observation light) from an observation target is collected on the image sensor by the optical system. The observation light is photoelectrically converted by the image sensor to generate an electrical signal corresponding to the observation light, i.e., an image signal corresponding to an observation image. The image signal is transmitted to a camera control unit (CCU) 11201 as RAW data.

[0137] The CCU 11201 is configured with a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), etc., and performs overall control of the operations of the endoscope 11100 and the display device 11202. Furthermore, the CCU 11201 receives an image signal from the camera head 11102, and performs various types of image processing on the image signal, such as development processing (demosaic processing), for displaying an image based on the image signal.

[0138] Under the control of the CCU 11201, the display device 11202 displays an image based on an image signal that has been subjected to image processing by the CCU 11201.

[0139] The light source device 11203 is composed of a light source such as an LED (Light Emitting Diode), and supplies the endoscope 11100 with irradiation light when photographing an operation site or the like.

[0140] The input device 11204 is an input interface for the endoscopic surgery system 11000. A user can input various information and instructions to the endoscopic surgery system 11000 via the input device 11204. For example, the user inputs an instruction to change the imaging conditions (type of irradiated light, magnification, focal length, etc.) of the endoscope 11100.

[0141] The treatment tool control device 11205 controls the driving of the energy treatment tool 11112 for cauterizing tissue, incising, sealing blood vessels, etc. The insufflation device 11206 sends gas into the body cavity of the patient 11132 via the insufflation tube 11111 to inflate the body cavity for the purpose of securing the field of view of the endoscope 11100 and securing the working space of the surgeon. The recorder 11207 is a device capable of recording various information related to the surgery. The printer 11208 is a device capable of printing various information related to the surgery in various formats such as text, image, or graph.

[0142] The light source device 11203 that supplies irradiation light to the endoscope 11100 when photographing the surgical site can be composed of a white light source composed of, for example, an LED, a laser light source, or a combination of these. When the white light source is composed of a combination of RGB laser light sources, the output intensity and output timing of each color (each wavelength) can be controlled with high precision, so that the white balance of the captured image can be adjusted in the light source device 11203. In this case, it is also possible to capture images corresponding to each of the RGB colors in a time-division manner by irradiating the observation object with laser light from each of the RGB laser light sources in a time-division manner and controlling the driving of the image sensor of the camera head 11102 in synchronization with the irradiation timing. According to this method, a color image can be obtained without providing a color filter to the image sensor.

[0143] The light source device 11203 may be controlled to change the intensity of the light it outputs at predetermined time intervals. The driving of the image sensor of the camera head 11102 may be controlled in synchronization with the timing of the change in the light intensity to obtain images in a time-division manner, and the images may be synthesized to generate an image with a high dynamic range that is free of so-called blackout and whiteout.

[0144] The light source device 11203 may be configured to supply light of a predetermined wavelength band corresponding to the special light observation. In the special light observation, for example, by utilizing the wavelength dependency of light absorption in body tissue, a narrow band light is irradiated compared to the irradiated light (i.e., white light) during normal observation, and a predetermined tissue such as blood vessels on the mucous membrane surface is photographed with high contrast, so-called narrow band imaging is performed. Alternatively, in the special light observation, a fluorescent observation may be performed in which an image is obtained by fluorescence generated by irradiating an excitation light. In the fluorescent observation, it is possible to irradiate an excitation light to a body tissue and observe the fluorescence from the body tissue (autofluorescence observation), or to locally inject a reagent such as indocyanine green (ICG) into the body tissue and irradiate the body tissue with excitation light corresponding to the fluorescent wavelength of the reagent to obtain a fluorescent image. The light source device 11203 may be configured to supply narrow band light and / or excitation light corresponding to such special light observation.

[0145] FIG. 20 is a block diagram showing an example of the functional configuration of the camera head 11102 and the CCU 11201 shown in FIG.

[0146] The camera head 11102 has a lens unit 11401, an imaging unit 11402, a drive unit 11403, a communication unit 11404, and a camera head control unit 11405. The CCU 11201 has a communication unit 11411, an image processing unit 11412, and a control unit 11413. The camera head 11102 and the CCU 11201 are connected to each other by a transmission cable 11400 so as to be able to communicate with each other.

[0147] The lens unit 11401 is an optical system provided at the connection portion with the lens barrel 11101. Observation light taken in from the tip of the lens barrel 11101 is guided to the camera head 11102 and enters the lens unit 11401. The lens unit 11401 is configured by combining a plurality of lenses including a zoom lens and a focus lens.

[0148] The imaging unit 11402 is composed of an imaging element. The imaging element constituting the imaging unit 11402 may be one (so-called single-plate type) or multiple (so-called multi-plate type). When the imaging unit 11402 is composed of a multi-plate type, for example, each imaging element may generate an image signal corresponding to each of RGB, and a color image may be obtained by combining the image signals. Alternatively, the imaging unit 11402 may be configured to have a pair of imaging elements for acquiring image signals for the right eye and the left eye corresponding to 3D (Dimensional) display. By performing 3D display, the surgeon 11131 can more accurately grasp the depth of the biological tissue in the surgical site. Note that when the imaging unit 11402 is composed of a multi-plate type, multiple lens units 11401 may be provided corresponding to each imaging element.

[0149] Furthermore, the imaging unit 11402 does not necessarily have to be provided in the camera head 11102. For example, the imaging unit 11402 may be provided inside the lens barrel 11101, immediately behind the objective lens.

[0150] The driving unit 11403 is configured by an actuator, and moves the zoom lens and focus lens of the lens unit 11401 by a predetermined distance along the optical axis under the control of the camera head control unit 11405. This allows the magnification and focus of the image captured by the imaging unit 11402 to be appropriately adjusted.

[0151] The communication unit 11404 is configured by a communication device for transmitting and receiving various information to and from the CCU 11201. The communication unit 11404 transmits the image signal obtained from the imaging unit 11402 to the CCU 11201 via the transmission cable 11400 as RAW data.

[0152] Furthermore, the communication unit 11404 receives a control signal for controlling the driving of the camera head 11102 from the CCU 11201, and supplies the control signal to the camera head control unit 11405. The control signal includes information on the imaging conditions, such as information specifying the frame rate of the captured image, information specifying the exposure value at the time of capturing the image, and / or information specifying the magnification and focus of the captured image.

[0153] The image capturing conditions such as the frame rate, exposure value, magnification, and focus may be appropriately specified by a user, or may be automatically set by the control unit 11413 of the CCU 11201 based on an acquired image signal. In the latter case, the endoscope 11100 is equipped with a so-called AE (Auto Exposure) function, AF (Auto Focus) function, and AWB (Auto White Balance) function.

[0154] The camera head control unit 11405 controls the driving of the camera head 11102 based on a control signal received from the CCU 11201 via the communication unit 11404.

[0155] The communication unit 11411 is configured with a communication device for transmitting and receiving various information to and from the camera head 11102. The communication unit 11411 receives an image signal transmitted from the camera head 11102 via the transmission cable 11400.

[0156] Furthermore, the communication unit 11411 transmits, to the camera head 11102, a control signal for controlling the driving of the camera head 11102. The image signal and the control signal can be transmitted by electrical communication, optical communication, or the like.

[0157] The image processing unit 11412 performs various types of image processing on the image signal, which is RAW data sent from the camera head 11102 .

[0158] The control unit 11413 performs various controls related to imaging of the surgical site etc. by the endoscope 11100 and display of the captured image obtained by imaging the surgical site etc. For example, the control unit 11413 generates a control signal for controlling the driving of the camera head 11102.

[0159] Further, the control unit 11413 causes the display device 11202 to display the captured image showing the surgical site, etc., based on the image signal that has been image-processed by the image processing unit 11412. At this time, the control unit 11413 may recognize various objects in the captured image using various image recognition techniques. For example, the control unit 11413 can recognize surgical tools such as forceps, specific living body parts, bleeding, mist when the energy treatment tool 11112 is used, etc., by detecting the shape and color of the edge of an object included in the captured image. When the control unit 11413 causes the display device 11202 to display the captured image, it may use the recognition result to superimpose various types of surgery support information on the image of the surgical site. By superimposing and presenting the surgery support information to the surgeon 11131, the burden on the surgeon 11131 can be reduced and the surgeon 11131 can proceed with the surgery reliably.

[0160] The transmission cable 11400 connecting the camera head 11102 and the CCU 11201 is an electrical signal cable for communication of electrical signals, an optical fiber for optical communication, or a composite cable of these.

[0161] Here, in the illustrated example, communication is performed wired using a transmission cable 11400, but communication between the camera head 11102 and the CCU 11201 may also be performed wirelessly.

[0162] An example of an endoscopic surgery system to which the technology according to the present disclosure can be applied has been described above. The technology according to the present disclosure can be applied to the imaging unit 11402 of the camera head 11102 in the configuration described above. Specifically, the imaging element 1 in FIG. 1 can be applied to the imaging unit 10402. By applying the technology according to the present disclosure to the imaging unit 10402, a clearer image of the surgical site can be obtained, allowing the surgeon to reliably confirm the surgical site.

[0163] Although an endoscopic surgery system has been described as an example here, the technology disclosed herein may also be applied to other systems, such as a microsurgery system.

[0164] <10. Application examples for mobile devices> The technology according to the present disclosure can be applied to various products. For example, the technology according to the present disclosure may be realized as a device mounted on any type of moving object, such as an automobile, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, a personal mobility device, an airplane, a drone, a ship, or a robot.

[0165] FIG. 21 is a block diagram showing a schematic configuration example of a vehicle control system, which is an example of a moving object control system to which the technology according to the present disclosure can be applied.

[0166] The vehicle control system 12000 includes a plurality of electronic control units connected via a communication network 12001. In the example shown in Fig. 21, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an outside-vehicle information detection unit 12030, an inside-vehicle information detection unit 12040, and an integrated control unit 12050. Also, as functional configurations of the integrated control unit 12050, a microcomputer 12051, an audio / video output unit 12052, and an in-vehicle network I / F (interface) 12053 are illustrated.

[0167] The drivetrain control unit 12010 controls the operation of devices related to the drivetrain of the vehicle in accordance with various programs. For example, the drivetrain control unit 12010 functions as a control device for a drive force generating device for generating a drive force of the vehicle, such as an internal combustion engine or a drive motor, a drive force transmission mechanism for transmitting the drive force to the wheels, a steering mechanism for adjusting the steering angle of the vehicle, and a braking device for generating a braking force of the vehicle.

[0168] The body system control unit 12020 controls the operation of various devices mounted on the vehicle body according to various programs. For example, the body system control unit 12020 functions as a control device for a keyless entry system, a smart key system, a power window device, or various lamps such as head lamps, back lamps, brake lamps, turn signals, and fog lamps. In this case, radio waves or signals of various switches transmitted from a portable device that replaces a key may be input to the body system control unit 12020. The body system control unit 12020 receives the input of these radio waves or signals and controls the door lock device, power window device, lamps, and the like of the vehicle.

[0169] The outside-vehicle information detection unit 12030 detects information outside the vehicle equipped with the vehicle control system 12000. For example, an imaging unit 12031 is connected to the outside-vehicle information detection unit 12030. The outside-vehicle information detection unit 12030 causes the imaging unit 12031 to capture an image outside the vehicle and receives the captured image. The outside-vehicle information detection unit 12030 may perform object detection processing or distance detection processing for a person, a car, an obstacle, a sign, or characters on a road surface, based on the received image.

[0170] The imaging unit 12031 is an optical sensor that receives light and outputs an electrical signal according to the amount of light received. The imaging unit 12031 can output the electrical signal as an image, or as distance measurement information. The light received by the imaging unit 12031 may be visible light or invisible light such as infrared light.

[0171] The in-vehicle information detection unit 12040 detects information inside the vehicle. For example, a driver state detection unit 12041 that detects the state of the driver is connected to the in-vehicle information detection unit 12040. The driver state detection unit 12041 includes, for example, a camera that captures an image of the driver, and the in-vehicle information detection unit 12040 may calculate the degree of fatigue or concentration of the driver based on the detection information input from the driver state detection unit 12041, or may determine whether the driver is dozing.

[0172] The microcomputer 12051 can calculate control target values ​​for the driving force generating device, the steering mechanism, or the braking device based on the information inside and outside the vehicle acquired by the outside-of-vehicle information detection unit 12030 or the inside-vehicle information detection unit 12040, and output a control command to the drive system control unit 12010. For example, the microcomputer 12051 can perform cooperative control aimed at realizing the functions of an ADAS (Advanced Driver Assistance System), including avoiding or mitigating a vehicle collision, following a vehicle based on the distance between vehicles, maintaining vehicle speed, warning a vehicle collision, or warning a vehicle from leaving a lane.

[0173] In addition, the microcomputer 12051 can perform cooperative control for the purpose of autonomous driving, which allows the vehicle to travel autonomously without relying on the driver's operation, by controlling the driving force generating device, steering mechanism, braking device, etc. based on information about the surroundings of the vehicle acquired by the outside vehicle information detection unit 12030 or the inside vehicle information detection unit 12040.

[0174] Furthermore, the microcomputer 12051 can output a control command to the body system control unit 12020 based on the information outside the vehicle acquired by the outside-vehicle information detection unit 12030. For example, the microcomputer 12051 can control the headlamps according to the position of a preceding vehicle or an oncoming vehicle detected by the outside-vehicle information detection unit 12030, and perform cooperative control for the purpose of preventing glare, such as switching from high beams to low beams.

[0175] The audio / video output unit 12052 transmits at least one output signal of audio and video to an output device capable of visually or audibly notifying information to passengers in the vehicle or the outside of the vehicle. In the example of Fig. 21, an audio speaker 12061, a display unit 12062, and an instrument panel 12063 are exemplified as the output device. The display unit 12062 may include at least one of an on-board display and a head-up display, for example.

[0176] FIG. 22 is a diagram showing an example of the installation position of the imaging unit 12031.

[0177] In FIG. 22, a vehicle 12100 has imaging units 12101, 12102, 12103, 12104, and 12105 as the imaging unit 12031.

[0178] The imaging units 12101, 12102, 12103, 12104, and 12105 are provided at positions such as the front nose, side mirrors, rear bumper, back door, and the upper part of the windshield in the vehicle interior of the vehicle 12100. The imaging unit 12101 provided at the front nose and the imaging unit 12105 provided at the upper part of the windshield in the vehicle interior mainly acquire images of the front of the vehicle 12100. The imaging units 12102 and 12103 provided at the side mirrors mainly acquire images of the sides of the vehicle 12100. The imaging unit 12104 provided at the rear bumper or back door mainly acquires images of the rear of the vehicle 12100. The images of the front acquired by the imaging units 12101 and 12105 are mainly used to detect a preceding vehicle, a pedestrian, an obstacle, a traffic light, a traffic sign, a lane, or the like.

[0179] 22 shows an example of the imaging ranges of the imaging units 12101 to 12104. An imaging range 12111 indicates the imaging range of the imaging unit 12101 provided on the front nose, imaging ranges 12112 and 12113 indicate the imaging ranges of the imaging units 12102 and 12103 provided on the side mirrors, respectively, and an imaging range 12114 indicates the imaging range of the imaging unit 12104 provided on the rear bumper or back door. For example, an overhead image of the vehicle 12100 viewed from above is obtained by superimposing the image data captured by the imaging units 12101 to 12104.

[0180] At least one of the imaging units 12101 to 12104 may have a function of acquiring distance information. For example, at least one of the imaging units 12101 to 12104 may be a stereo camera made up of a plurality of imaging elements, or may be an imaging element having pixels for detecting a phase difference.

[0181] For example, the microcomputer 12051 can extract, as a preceding vehicle, a three-dimensional object that is the closest three-dimensional object on the travel path of the vehicle 12100 and travels at a predetermined speed (for example, 0 km / h or more) in approximately the same direction as the vehicle 12100, by calculating the distance to each three-dimensional object in the imaging ranges 12111 to 12114 and the change over time of this distance (relative speed with respect to the vehicle 12100) based on the distance information obtained from the imaging units 12101 to 12104. Furthermore, the microcomputer 12051 can set a vehicle distance to be secured in advance in front of the preceding vehicle, and perform automatic brake control (including follow-up stop control) and automatic acceleration control (including follow-up start control). In this way, cooperative control can be performed for the purpose of automatic driving that travels autonomously without relying on the driver's operation.

[0182] For example, the microcomputer 12051 classifies and extracts three-dimensional object data on three-dimensional objects into two-wheeled vehicles, ordinary vehicles, large vehicles, pedestrians, utility poles, and other three-dimensional objects based on distance information obtained from the imaging units 12101 to 12104, and can use the data for automatic obstacle avoidance. For example, the microcomputer 12051 distinguishes obstacles around the vehicle 12100 into obstacles that are visible to the driver of the vehicle 12100 and obstacles that are difficult to see. Then, the microcomputer 12051 determines a collision risk indicating the risk of collision with each obstacle, and when the collision risk is equal to or greater than a set value and a collision is possible, the microcomputer 12051 can provide driving assistance for collision avoidance by outputting an alarm to the driver via the audio speaker 12061 or the display unit 12062, or by performing forced deceleration or avoidance steering via the drive system control unit 12010.

[0183] At least one of the imaging units 12101 to 12104 may be an infrared camera that detects infrared rays. For example, the microcomputer 12051 can recognize a pedestrian by determining whether or not a pedestrian is present in the captured images of the imaging units 12101 to 12104. The recognition of such a pedestrian is performed, for example, by a procedure of extracting feature points in the captured images of the imaging units 12101 to 12104 as infrared cameras, and a procedure of performing pattern matching processing on a series of feature points that indicate the contour of an object to determine whether or not the object is a pedestrian. When the microcomputer 12051 determines that a pedestrian is present in the captured images of the imaging units 12101 to 12104 and recognizes the pedestrian, the audio / image output unit 12052 controls the display unit 12062 to superimpose a rectangular contour line for emphasis on the recognized pedestrian. The audio / image output unit 12052 may also control the display unit 12062 to display an icon or the like indicating a pedestrian at a desired position.

[0184] An example of a vehicle control system to which the technology according to the present disclosure can be applied has been described above. The technology according to the present disclosure can be applied to the imaging unit 12031 and the like among the configurations described above. Specifically, the imaging element 1 in FIG. 1 can be applied to the imaging unit 12031 and the like. By applying the technology according to the present disclosure to the imaging unit 12031 and the like, a clearer captured image can be obtained, thereby reducing the driver's fatigue.

[0185] Finally, the above-mentioned embodiments are merely examples of the present disclosure, and the present disclosure is not limited to the above-mentioned embodiments. Therefore, even if the embodiments are different from the above-mentioned embodiments, various modifications can be made depending on the design, etc., as long as they do not deviate from the technical idea of ​​the present disclosure.

[0186] In addition, the effects described in this specification are merely examples and are not limiting, and other effects may also be obtained.

[0187] In addition, the drawings in the above-mentioned embodiments are schematic, and the dimensional ratios of the various parts do not necessarily correspond to the actual ones. In addition, the drawings may include parts whose dimensional relationships and ratios differ from one another.

[0188] The present technology can also be configured as follows. (1) A pixel including a photoelectric conversion unit that performs photoelectric conversion in response to incident light and a charge transfer unit that transfers charges generated by the photoelectric conversion; an individual on-chip lens arranged for each pixel and configured to individually focus the incident light; A plurality of phase difference pixels each including the photoelectric conversion unit and the charge transfer unit and arranged adjacent to each other to detect a phase difference; a common on-chip lens that is disposed in common to the plurality of phase difference pixels and commonly collects the incident light; a pixel circuit formed on a semiconductor substrate for generating an image signal based on the transferred charges; Equipped with The charge transfer units of the phase difference pixels are disposed in a region between the common on-chip lens and the individual on-chip lens. Image sensor. (2) The imaging element according to (1), wherein the pixel circuit is formed on a front surface side of the semiconductor substrate. (3) The imaging element according to (2), wherein the photoelectric conversion unit is formed on the semiconductor substrate and performs photoelectric conversion of the incident light that is incident on a back surface that is different from the front surface. (4) The image sensor according to (3), wherein the charge transfer section is constituted by a vertical transistor that transfers charges in a thickness direction of the semiconductor substrate. (5) The imaging element according to (2), wherein the photoelectric conversion section is constituted by a photoelectric conversion film arranged adjacent to the rear surface side of the semiconductor substrate. (6) The imaging element according to (5), wherein the charge transfer section is constituted by a through electrode that is an electrode that penetrates the semiconductor substrate. (7) The imaging element according to (5) above, further comprising a color filter that transmits light of a predetermined wavelength out of the incident light. (8) The image sensor according to (7), wherein the color filter is disposed between the individual on-chip lens and the photoelectric conversion film and between the common on-chip lens and the photoelectric conversion film. (9) The imaging element according to (7), wherein the color filter is disposed between the photoelectric conversion film and the semiconductor substrate. (10) The imaging element according to any one of (1) to (9), further comprising a separator disposed between the photoelectric conversion units of the phase difference pixels. (11) A pixel including a photoelectric conversion unit that performs photoelectric conversion in response to incident light and a charge transfer unit that transfers charges generated by the photoelectric conversion; an individual on-chip lens arranged for each pixel and configured to individually focus the incident light; A plurality of phase difference pixels each including the photoelectric conversion unit and the charge transfer unit and arranged adjacent to each other to detect a phase difference; a common on-chip lens that is disposed in common to the plurality of phase difference pixels and commonly collects the incident light; a pixel circuit formed on a semiconductor substrate for generating an image signal based on the transferred charges; a processing circuit for processing the generated image signal; Equipped with The charge transfer units of the phase difference pixels are disposed in a region between the common on-chip lens and the individual on-chip lens. Imaging device. [Explanation of symbols]

[0189] 1. Image sensor 2. Pixel array section 4 Column signal processing section 11, 13, 15, 19 Photoelectric conversion unit 12, 12a, 12b, 16 Charge transfer section 14 Switching element 20, 20a, 20b, 20c pixel circuit 21, 21a, 21b, 21c Charge holding section 100, 100a, 100b, 100c pixels 110 Semiconductor substrate 121, 121a, 121b, 122 to 124, 125a, 125b, 126 Gate electrodes 139 Through electrode 142 Separation section 150 Color Filters 151 High refractive index film 161 Electrode for charge storage 162 Insulating film 163 1st electrode 164 Photoelectric conversion film 165 2nd electrode 181 On-chip lens 182 Common On-Chip Lens 200, 200a Phase difference pixel 1000 Cameras 1002 Image sensor 1005 Image processing section 10402, 12031, 12101~12105 Imaging section

Claims

1. A pixel array section including a plurality of pixels formed on a semiconductor substrate, each of which has a photoelectric conversion section that performs photoelectric conversion in response to incident light and a charge transfer section that transfers charges generated by the photoelectric conversion, and a plurality of phase difference pixels that each have the photoelectric conversion section and the charge transfer section and are arranged adjacent to each other to detect a phase difference, the phase difference pixels being arranged in a two-dimensional lattice pattern, each said pixel having an individual on-chip lens for individually focusing said incident light; Each of the pixels and each of the phase difference pixels has a pixel circuit formed on the semiconductor substrate and generating an image signal based on the charge transferred by the charge transfer unit, The pixel array unit includes: a common on-chip lens that is disposed in common to the plurality of phase difference pixels and commonly collects the incident light; a separation portion disposed in a wall shape surrounding the semiconductor substrate at a boundary between the adjacent pixels, the charge transfer unit has a semiconductor region different from a semiconductor region constituting the photoelectric conversion unit and a gate electrode; The different semiconductor regions and the gate electrodes constituting the charge transfer units of the phase difference pixels are disposed in regions that do not overlap with the common on-chip lens, the individual on-chip lens, and the separation unit in a plan view. Image sensor.

2. The image sensor according to claim 1 , wherein the pixel circuits are formed on a front surface side of the semiconductor substrate.

3. The image sensor according to claim 2 , wherein the photoelectric conversion section is formed on the semiconductor substrate and performs photoelectric conversion of the incident light that is incident on a back surface that is different from the front surface.

4. 4. The image sensor according to claim 3, wherein the charge transfer section is formed of a vertical transistor that transfers charges in a thickness direction of the semiconductor substrate.

5. The image sensor according to claim 2 , wherein the photoelectric conversion portion is formed of a photoelectric conversion film disposed adjacent to the rear surface side of the semiconductor substrate.

6. 6. The image sensor according to claim 5, wherein the charge transfer portion is formed of a through electrode that is an electrode that penetrates the semiconductor substrate.

7. 6. The image sensor according to claim 5, further comprising a color filter that transmits light of a predetermined wavelength out of the incident light.

8. The image sensor according to claim 7 , wherein the color filters are disposed between the individual on-chip lenses and the photoelectric conversion film, and between the common on-chip lens and the photoelectric conversion film.

9. The image sensor according to claim 7 , wherein the color filter is disposed between the photoelectric conversion film and the semiconductor substrate.

10. The imaging element according to claim 1 , further comprising a separator disposed between the photoelectric conversion units of the phase difference pixels.

11. An imaging element according to any one of claims 1 to 10; a processing circuit for processing an image signal generated by the pixel circuit; Equipped with Imaging device.

Images