WO2021111904A1

WO2021111904A1 - Imaging element and imaging device

Info

Publication number: WO2021111904A1
Application number: PCT/JP2020/043422
Authority: WO
Inventors: 界斗横地; 純次成瀬
Original assignee: ソニーセミコンダクタソリューションズ株式会社
Priority date: 2019-12-06
Filing date: 2020-11-20
Publication date: 2021-06-10
Also published as: JP2021090022A

Abstract

The present technology relates to an imaging element and an imaging device, which make it possible to retain light incident on a photoelectric conversion part of the imaging element in the photoelectric conversion part, and improve sensitivity. This imaging element is provided with: an on-chip lens that condenses incident light; a photoelectric conversion part that performs photoelectric conversion on the incident light; a waveguide that guides the incident light to the photoelectric conversion part in an opening having approximately the same size as the condensation size of the incident light; a reflective film that reflects the incident light transmitted through the photoelectric conversion part; and a relief region having a plurality of recesses and protrusions on the side on which the incident light is incident of the photoelectric conversion part. The reflective film has an inclined surface. The present technology is applicable to an imaging element.

Description

Image sensor and image sensor

The present technology relates to an image sensor and an image sensor, for example, an image sensor in which incident light is emitted from the back surface of a semiconductor substrate and an image sensor using the image sensor.

An image sensor is used in which the incident light is irradiated to the back surface side of the semiconductor substrate on which the photoelectric conversion part such as a photodiode that photoelectrically converts the incident light is formed. Since the incident light is applied to the photoelectric conversion unit without passing through the wiring region formed on the surface of the semiconductor substrate, the sensitivity can be improved.

As such an image pickup device, for example, an image pickup device in which a photodiode or the like is formed on a silicon layer of an SOI (Silicon on Insulator) substrate formed by sequentially laminating an intermediate layer and a silicon layer on a silicon substrate is used. (See, for example, Patent Document 1). In such an image pickup device, a wiring portion (wiring region) is arranged on the surface of a silicon layer on which a light receiving sensor portion such as a photodiode is formed. After the support substrate is adhered to this wiring region, the silicon substrate and the intermediate layer are removed. As the silicon layer, thin film silicon having a thickness of 10 μm or less can be used. Since the process of thinning the semiconductor substrate by grinding or the like is not required, a silicon layer having a stable thickness can be manufactured with a high yield.

JP-A-2007-335905

Since a thin silicon layer is used for the semiconductor substrate on which the photodiode or the like is formed, the incident light that is not absorbed by the semiconductor substrate among the incident light reaches the wiring region and is reflected, and the image sensor is again used. There was a possibility that it would be incident on.

This technology was made in view of such a situation, and makes it possible to improve the sensitivity by also utilizing the reflected light of the image sensor.

The first imaging element on one aspect of the present technology includes an on-chip lens that collects incident light, a photoelectric conversion unit that performs photoelectric conversion of the incident light, and a size that is substantially the same as the condensed size of the incident light. In the opening, a waveguide that guides the incident light to the photoelectric conversion unit, a reflective film that reflects the incident light that has passed through the photoelectric conversion unit, and a plurality of sides of the photoelectric conversion unit on which the incident light is incident. It is provided with an uneven region having unevenness.

The first image sensor on one aspect of the present technology includes an on-chip lens that collects incident light, a photoelectric conversion unit that performs photoelectric conversion of the incident light, and a size that is substantially the same as the condensed size of the incident light. In the opening, a waveguide that guides the incident light to the photoelectric conversion unit, a reflective film that reflects the incident light that has passed through the photoelectric conversion unit, and a plurality of sides of the photoelectric conversion unit on which the incident light is incident. It includes an image pickup element having an unevenness region having irregularities and a processing unit for processing a signal from the image pickup element.

The second imaging element on one aspect of the present technology includes an on-chip lens that collects incident light, a photoelectric conversion unit that performs photoelectric conversion of the incident light, and a size that is substantially the same as the condensed size of the incident light. An opening, a reflective film that reflects the incident light transmitted through the photoelectric conversion unit, a reflective film having an inclined surface, and a concavo-convex region having a plurality of irregularities on the side of the photoelectric conversion unit on which the incident light is incident. And.

The second image sensor on one aspect of the present technology has an on-chip lens that collects incident light, a photoelectric conversion unit that performs photoelectric conversion of the incident light, and a size that is substantially the same as the condensed size of the incident light. An opening, a reflective film that reflects the incident light transmitted through the photoelectric conversion unit, a reflective film having an inclined surface, and a concavo-convex region having a plurality of irregularities on the side of the photoelectric conversion unit on which the incident light is incident. It is provided with an image pickup device including the above and a processing unit for processing a signal from the image pickup device.

In the first image pickup element on one aspect of the present technology, an on-chip lens that collects incident light, a photoelectric conversion unit that performs photoelectric conversion of the incident light, and an opening having a size substantially the same as the condensed size of the incident light. There are a waveguide that guides the incident light to the photoelectric conversion unit, a reflective film that reflects the incident light that has passed through the photoelectric conversion unit, and an uneven region that has a plurality of irregularities on the side where the incident light of the photoelectric conversion unit is incident. Be prepared.

The first image pickup device on one aspect of the present technology is provided with the first image pickup element.

In the second imaging element on one aspect of the present technology, an on-chip lens that collects incident light, a photoelectric conversion unit that performs photoelectric conversion of the incident light, and an opening having a size substantially the same as the condensed size of the incident light. A portion, a reflective film that reflects incident light transmitted through the photoelectric conversion unit, a reflective film having an inclined surface, and a concavo-convex region having a plurality of irregularities on the side where the incident light of the photoelectric conversion unit is incident are provided. There is.

The second image pickup device on one aspect of the present technology is provided with the second image pickup element.

The imaging device may be an independent device or an internal block constituting one device.

It is a figure which shows the structure of one Embodiment of the image pickup device to which this technique is applied. It is a figure which shows the structural example of the pixel which concerns on 1st Embodiment. It is a figure which shows an example of the incident light to an image sensor, and the reflected light. It is a figure which shows the other structural example of the pixel which concerns on 1st Embodiment. It is a figure which shows the structural example of the pixel which concerns on 2nd Embodiment. It is a figure which shows the structural example of the pixel which concerns on 3rd Embodiment. It is a figure which shows the structural example of the pixel which concerns on 4th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 5th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 6th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 7th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 8th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 9th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 10th Embodiment. It is a figure for demonstrating the size of the waveguide. It is a figure for demonstrating the arrangement position of the waveguide. It is a figure which shows the other structural example of the pixel which concerns on 10th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 11th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 12th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 13th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 14th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 15th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 16th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 17th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 18th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 19th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 20th Embodiment. It is a figure which shows the structural example of the pixel which concerns on 21st Embodiment. It is a figure for demonstrating an application example. It is a figure for demonstrating an application example. It is a figure for demonstrating an application example. It is a figure for demonstrating an application example. It is a figure for demonstrating an application example. It is a figure for demonstrating an application example. It is a figure for demonstrating an application example. It is a figure for demonstrating an application example. It is a figure for demonstrating an application example. It is a figure for demonstrating an application example. It is a figure which shows an example of the schematic structure of the endoscopic surgery system. It is a block diagram which shows an example of the functional structure of a camera head and a CCU. It is a block diagram which shows an example of the schematic structure of a vehicle control system. It is explanatory drawing which shows an example of the installation position of the vehicle exterior information detection unit and the image pickup unit.

The embodiment for implementing the present technology (hereinafter referred to as the embodiment) will be described below.

<Structure of image sensor>
FIG. 1 is a diagram showing a configuration example of an image pickup device according to an embodiment of the present technology. The image pickup device 1 in the figure includes a pixel array unit 10, a vertical drive unit 11, a column signal processing unit 12, and a control unit 13.

The pixel array unit 10 is configured by arranging the pixels 30 in a two-dimensional grid pattern. Here, the pixel 30 generates an image signal according to the irradiated light. The pixel 30 has a photoelectric conversion unit that generates an electric charge according to the irradiated light. Further, the pixel 30 further has a pixel circuit. This pixel circuit generates an image signal based on the electric charge generated by the photoelectric conversion unit. The generation of the image signal is controlled by the control signal generated by the vertical drive unit 11.

A signal line 14 and a signal line 15 are arranged in an XY matrix in the pixel array unit 10. The signal line 14 is a signal line that transmits a control signal of the pixel circuit in the pixel 30, is arranged for each line of the pixel array unit 10, and is commonly wired to the pixel 30 arranged in each line. The signal line 15 is a signal line for transmitting an image signal generated by the pixel circuit of the pixel 30, is arranged for each row of the pixel array unit 10, and is commonly wired to the pixels 30 arranged in each row. To. These photoelectric conversion units and pixel circuits are formed on a semiconductor substrate.

The vertical drive unit 11 generates a control signal for the pixel circuit of the pixel 30. The vertical drive unit 11 transmits the generated control signal to the pixel 30 via the signal line 14 in the figure. The column signal processing unit 12 processes the image signal generated by the pixel 30. The column signal processing unit 12 processes the image signal transmitted from the pixel 30 via the signal line 15 in the figure. The processing in the column signal processing unit 12 corresponds to, for example, analog-to-digital conversion that converts an analog image signal generated in the pixel 30 into a digital image signal.

The image signal processed by the column signal processing unit 12 is output as an image signal of the image sensor 1. The control unit 13 controls the entire image sensor 1. The control unit 13 controls the image sensor 1 by generating and outputting a control signal for controlling the vertical drive unit 11 and the column signal processing unit 12. The control signal generated by the control unit 13 is transmitted to the vertical drive unit 11 and the column signal processing unit 12 by the

signal lines

16 and 17, respectively.

<Pixel configuration according to the first embodiment>
FIG. 2 is a cross-sectional view showing a configuration example of a pixel according to the first embodiment of the present technology.

The pixel 30 includes a semiconductor substrate 31, a semiconductor region 32, a wiring region 33, a front surface side reflective film 34, a back surface side reflective film 35, a protective film 36, and an on-chip lens 37.

The semiconductor substrate 31 is a semiconductor substrate on which the semiconductor region (diffusion region) of the elements constituting the photoelectric conversion unit and the pixel circuit described above is formed. The semiconductor substrate 31 can be made of silicon (Si). A semiconductor element such as a photoelectric conversion unit is arranged in a well region formed on the semiconductor substrate 31. For convenience, it is assumed that the semiconductor substrate 31 in the figure constitutes a p-type well region.

By forming an n-type semiconductor region in this p-type well region, a diffusion region of the device can be formed. On the semiconductor substrate 31 in the figure, an n-type semiconductor region 32 constituting a photoelectric conversion unit is described as an example of an element. The photodiode formed by the pn junction at the interface between the n-type semiconductor region 32 and the surrounding p-type well region corresponds to the photoelectric conversion unit. When the n-type semiconductor region 32 is irradiated with incident light, photoelectric conversion occurs. The electric charge generated by this photoelectric conversion is accumulated in the n-type semiconductor region 32. An image signal is generated by a pixel circuit (not shown) based on the accumulated charge.

Note that the separation region 38 can be arranged at the boundary of the pixels 30 in the semiconductor substrate 31 in the figure. The separation region 38 optically separates the pixels 30. Specifically, by arranging a film that reflects the incident light between the pixels 30 as the separation region 38, leakage of the incident light to the adjacent pixels 30 is prevented. This makes it possible to prevent crosstalk between the pixels 30. The separation region 38 can be made of, for example, a metal such as tungsten (W).

A fixed charge film and an insulating film can be arranged between the separation region 38 and the semiconductor substrate 31. The fixed charge film is a film that is arranged at the interface of the semiconductor substrate 31 and pins the surface level of the semiconductor substrate 31. The insulating film is a film that is arranged between the fixed charge film and the separation region 38 to insulate the separation region 38. Such a separation region 38 can be formed by forming a fixed charge film and an insulating film on the surface of the groove formed in the semiconductor substrate 31 and embedding a metal such as tungsten (W). By arranging the separation region 38 provided with such an insulating film, the pixels 30 can be electrically separated.

The wiring area 33 is an area that is arranged adjacent to the surface of the semiconductor substrate 31 and on which wiring for transmitting signals is formed. The wiring region 33 in the figure includes a wiring layer 42 and an insulating layer 41. The wiring layer 42 is a conductor that transmits a signal to the elements of the semiconductor substrate 31. The wiring layer 42 can be made of a metal such as copper (Cu) or tungsten (W).

The insulating layer 41 insulates the wiring layer 42. The insulating layer 41 can be made of, for example, silicon oxide (SiO2). The wiring layer 42 and the insulating layer 41 can be configured in multiple layers. The figure shows an example of wiring configured in two layers. Wiring layers 42 arranged in different layers can be connected to each other by a via plug (not shown).

The image sensor 1 in the figure corresponds to a back-illuminated image sensor in which incident light is irradiated from the back surface side of the semiconductor substrate 31 to the photoelectric conversion unit. The incident light from the subject incident on the semiconductor substrate 31 via the on-chip lens 37 and the back surface side reflective film 35, which will be described later, is absorbed by the semiconductor substrate 31 and photoelectrically converted. However, the incident light that is not absorbed by the semiconductor substrate 31 passes through the semiconductor substrate 31 and becomes transmitted light, and is incident on the wiring region 33.

The surface-side reflective film 34 is arranged on the surface side of the semiconductor substrate 31 and reflects transmitted light. The surface-side reflective film 34 in the figure is arranged in the wiring region 33, and is arranged adjacent to the semiconductor substrate 31 via the insulating layer 41. The surface-side reflective film 34 is configured to cover the surface side of the semiconductor substrate 31 of the pixel 30.

By arranging the surface-side reflective film 34, the transmitted light transmitted through the semiconductor substrate 31 can be reflected to the semiconductor substrate 31 side. This makes it possible to increase the incident light that contributes to photoelectric conversion. Therefore, the conversion efficiency of the pixel 30 can be improved. The surface-side reflective film 34 can be made of a metal such as W or Cu. Further, the surface side reflective film 34 can be formed by the wiring layer 42. In this case, the surface-side reflective film 34 can be formed at the same time as the wiring layer 42.

The back surface side reflective film 35 is arranged on the back surface side of the semiconductor substrate 31 to transmit the incident light from the subject and further reflect the reflected light. The back surface side reflective film 35 in the figure is arranged adjacent to the semiconductor substrate 31 via the protective film 36. The back surface side reflective film 35 is provided with an opening 52 in the central portion, and the incident light collected by the on-chip lens 37 described later is transmitted through the opening 52. Further, the back surface side reflective film 35 reflects the above-mentioned reflected light again and causes it to enter the semiconductor substrate 31 to reduce leakage of the reflected light to the outside of the pixel 30. The back surface side reflective film 35 can be made of a metal such as W or Cu, like the front surface side reflective film 34 and the separation region 38.

Further, the back surface side reflective film 35 can be formed at the same time as the separation region 38. Specifically, when the metal used as the material of the separation region 38 is embedded in the groove formed in the semiconductor substrate 31, a material film is also formed on the back surface of the semiconductor substrate 31. By forming the opening 52 in the formed material film, the back surface side reflective film 35 can be manufactured. The opening 52 can be configured to have substantially the same size as the condensed size of the incident light by the on-chip lens 37.

The protective film 36 is a film that insulates and protects the back surface side of the semiconductor substrate 31. The protective film 36 in the figure is configured to cover the back surface side reflective film 35, and further flattens the back surface side of the semiconductor substrate 31 on which the back surface side reflective film 35 is arranged. The protective film 36 can be made of, for example, SiO2. The above-mentioned fixed charge film can be arranged on the portion of the protective film 36 adjacent to the surface of the semiconductor substrate 31. For the fixed charge film, for example, oxides of metals such as hafnium, aluminum and tantalum can be used.

The on-chip lens 37 is a lens that is arranged for each pixel 30 and collects incident light from a subject on a photoelectric conversion unit of a semiconductor substrate 31. The on-chip lens 37 is configured in a convex lens shape and collects incident light. The on-chip lens 37 in the figure collects incident light on the photoelectric conversion unit through the opening 52 of the back surface side reflective film 35 described above. The on-chip lens 37 can be made of, for example, an organic material such as resin or an inorganic material such as silicon nitride (SiN).

As shown in the figure, the incident light is focused by the on-chip lens 37, and a focal point is formed in the region of the semiconductor substrate 31. The light incident on the on-chip lens 37 is gradually narrowed down from the on-chip lens 37 to the semiconductor substrate 31, and the focused size, which is the irradiation range of the incident light in the horizontal direction, is narrowed. By configuring the opening 52 of the back surface side reflective film 35 to have a size substantially equal to the focused size of the incident light, the incident light collected by the on-chip lens 37 is shielded (vignetting) by the back surface side reflecting film 35. Can be prevented. Since the opening 52 is reduced, leakage of reflected light from the opening 52 can be reduced.

Further, the pixel 30 constituting the image pickup device 1 shown in FIG. 2 includes a substrate back surface scattering portion 51. A part of the reflected light of the pixel 30 may leak from the opening 52 of the back surface reflective film 35, but by providing the substrate back surface scattering portion 51, the reflected light leaking from the opening 52 is scattered. The configuration can be returned to the semiconductor region 32.

The substrate back surface scattering portion 51 is formed on the back surface of the semiconductor substrate 31 and scatters incident light and reflected light. The substrate back surface scattering portion 51 can be formed by irregularities formed on the back surface of the semiconductor substrate 31. The substrate back surface scattering portion 51 is a region having a plurality of concave portions and convex portions. Since the substrate back surface scattering portion 51 is a region having irregularities, it can be configured to scatter incident light. The substrate back surface scattering portion 51 in the figure is arranged in the vicinity of the opening 52 of the back surface side reflective film 35. Further, as shown in the figure, the substrate back surface scattering portion 51 is provided on the back surface side between the separation regions 38.

The reflected light leaking to the outside of the pixel 30 through the opening 52 is scattered by the back surface scattering portion 51 of the substrate, so that it is dispersed and irradiated over a wide range. Therefore, flare and the like can be made inconspicuous. The substrate back surface scattering portion 51 can be formed, for example, by partially etching the back surface of the semiconductor substrate 31. For example, the back surface scattering portion 51 of the substrate can be formed by performing anisotropic etching on the back surface of the semiconductor substrate 31 to form a plurality of V-shaped recesses shown in the figure.

As described above, the pixel 30 of the image pickup device 1 of the first embodiment scatters the reflected light leaking to the outside of the pixel 30 by arranging the substrate back surface scattering portion 51 on the back surface side of the semiconductor substrate 31. Let me. Thereby, the image quality can be improved.

<Reflection of incident light>
With reference to FIG. 3, the leakage of the reflected light can be reduced by reducing the opening 52, and the reflected light can be returned to the semiconductor region 32 by providing the back surface scattering portion 51 of the substrate. Add an explanation about what will happen.

The solid arrow in FIG. 3 represents the incident light, and the dotted arrow represents the reflected light. Further, the incident light 71 in the figure shows an example in which the incident light 71 is repeatedly reflected by the front surface side reflective film 34 and the back surface side reflective film 35 after passing through the semiconductor substrate 31. The reflected light undergoes photoelectric conversion as the reflection is repeated, is gradually attenuated, and is absorbed without leaking to the outside of the pixel 30.

The incident light can be confined inside the semiconductor substrate 31, and the sensitivity can be improved. Further, by narrowing the opening 52 of the back surface side reflective film 35, it is possible to reduce the passage of the reflected light from the front surface side reflective film 34 through the opening 52. Leakage of reflected light to the outside of the pixel 30 can be reduced. If the reflected light leaks to the outside of the pixel 30 and then re-enters the nearby pixel 30, it causes noise such as flare. By narrowing the opening 52, noise can be reduced and deterioration of image quality can be prevented.

Further, by providing the substrate back surface scattering portion 51, the reflected light can be scattered even in the substrate back surface scattering portion 51 and returned inside the semiconductor substrate 31. Therefore, the reflected light can be confined in the semiconductor substrate 31 by the substrate back surface scattering portion 51 as well. Therefore, the sensitivity can be improved.

Note that FIGS. 2 and 3 show a configuration in which the back surface scattering portion 51 of the substrate is provided not only in the region of the opening 52 but also on the lower side (semiconductor substrate 31 side) of the back surface side reflective film 35. Since the reflected light can be returned to the semiconductor substrate 31 by the back surface side reflective film 35, the substrate back surface scattering portion 51 may not be provided under the back surface side reflective film 35. In other words, the substrate back surface scattering portion 51 may be configured to be provided only at the opening 52.

Further, the back surface side reflective film 35 may have a two-layer structure as shown in FIG. The pixel 30 shown in FIG. 4 includes an absorbing film 91 on the back surface side reflective film 35.

The absorption film 91 is arranged on the back surface of the semiconductor substrate 31 to absorb the incident light from the subject. The absorption film 91 is provided with an opening 52 in the central portion, and the incident light collected by the on-chip lens 37 is transmitted through the opening 52. On the other hand, the light incident on the portion other than the opening 52, that is, the absorption film 91 is absorbed by the absorption film 91.

The absorbing film 91 is also provided to absorb the reflected light and reduce the leakage of the reflected light to the outside of the pixel 30. The absorption film 91 in the figure is arranged between the on-chip lens 37 and the back surface side reflection film 35, and is provided where the back surface side reflection film 35 is provided.

The absorption film 91 can be composed of, for example, a film in which an absorption member that absorbs incident light is dispersed. For example, a pigment that absorbs light such as carbon black or titanium oxide can be used as an absorbing member, and the absorbing film 91 can be formed by a film in which this pigment is dispersed in a resin or the like. Such an absorption film 91 can be manufactured by forming a resin film in which a pigment is dispersed adjacent to a back surface side reflection film 35 to form an opening 52.

The opening 52 can be formed by dry etching or wet etching using a chemical solution. An absorption film 91 having a dye-based absorption member such as an infrared light absorber can also be used.

By arranging the absorption film 91, the reflected light or the incident light that obliquely passes through the opening 52 of the back surface side reflection film 35 can be incident on the wall surface of the absorption film 91 in the opening 52 and absorbed.

In the following description, the pixel 30 provided with the absorbing film 91 will be described as an example. Further, the pixel 30 shown in FIG. 4 is referred to as a pixel 30 according to the first embodiment, and is described as a pixel 30a in order to distinguish it from the pixel 30 according to another embodiment.

<Pixel configuration according to the second embodiment>
FIG. 5 is a cross-sectional view showing a configuration example of the pixel 30b according to the second embodiment of the present technology. In the pixel 30b shown in FIG. 5, the same parts as those of the pixel 30a according to the first embodiment shown in FIG. 4 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

The pixel 30b according to the second embodiment shown in FIG. 5 has a different shape of the surface side reflective film 34 as compared with the pixel 30a according to the first embodiment, and is a surface side reflective film 101. The point is different.

The surface-side reflective film 101 in the pixel 30b is formed in a shape (mountain shape) in which the central portion protrudes. In other words, the surface-side reflective film 101 has a shape like a combination of a quadrangle and a triangle, and when the quadrangle is used as a base, the shape is such that a triangle is placed on the central portion of the base of the quadrangle. ..

Although FIG. 5 shows a case where the surface-side reflective film 101 has a shape in which a quadrangle and a triangle are combined, it may be a triangle. Further, the vertices of the triangle may have a rounded shape. The surface-side reflective film 101 may have a shape having an inclined surface on the semiconductor region 32 side.

The surface-side reflective film 101 is configured so that the sides facing each other of the semiconductor region 32 and the surface-side reflective film 101 are not parallel to each other. In other words, at least one side of the surface-side reflective film 101 is formed as a slope, and the example shown in FIG. 5 shows an example in which two sides are formed as a slope.

Here, refer to FIG. 3 again. FIG. 3 is a diagram showing incident light and reflected light in the pixel 30a according to the first embodiment. As described with reference to FIG. 3, the incident light 71 is repeatedly reflected by the front surface side reflection film 34 and the back surface side reflection film 35, and is confined inside the semiconductor substrate 31. As shown as incident light 72 in FIG. 3, the incident light includes light that is vertically incident (light called a 0th-order component or the like), and such light is the surface-side reflective film 34. There was a possibility that the light would come out of the opening 52.

Since the pixel 30a shown in FIG. 3 includes the substrate back surface scattering portion 51, the incident light can be scattered and the reflected light can be scattered. Therefore, it is possible to reduce the amount of light that is reflected by the surface-side reflective film 34 and escapes from the opening 52. Further, in order to reduce the amount of light reflected by the surface-side reflective film 34 and passing through the opening 52, the shape of the surface-side reflective film 34 is shown in the surface-side reflective film 101 (FIG. 5). Shape.

The surface-side reflective film 101 included in the pixel 30b shown in FIG. 5 is formed in a triangular shape as described above. An example of incident light and reflected light is indicated by an arrow in the pixel 30b shown on the left side of FIG. As shown in the pixel 30b illustrated on the left side of FIG. 5, the incident light hits one side of the triangular surface-side reflective film 101, is reflected, and is directed toward the side surface of the semiconductor region 32. Therefore, the structure can be prevented from being reflected by the surface-side reflective film 101 and coming out of the opening 52.

In this way, by providing a hypotenuse on at least one side of the surface-side reflective film 101 and configuring the hypotenuse so that incident light hits and reflects the hypotenuse, the amount of light that can be returned to the semiconductor region 32 can be increased. It is possible to improve the sensitivity of the pixel 30b.

Note that FIG. 5 shows an example in which the surface-side reflective film 101 is arranged near the center of the pixel 30b, but this position is an example. For example, the surface-side reflective film 101 is arranged at a position avoiding a region where a gate of a transfer transistor (not shown) for reading the electric charge accumulated in the semiconductor region 32 is formed, and is displaced from the vicinity of the center of the pixel 30b. It may be arranged in. The same applies to other embodiments.

<Pixel configuration according to the third embodiment>
FIG. 6 is a cross-sectional view showing a configuration example of the pixel 30c according to the third embodiment of the present technology. In the pixel 30c shown in FIG. 6, the same parts as those of the pixel 30b according to the second embodiment shown in FIG. 5 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

The pixel 30c according to the third embodiment shown in FIG. 6 is different from the pixel 30b according to the second embodiment in that the reflecting portion 111 is further provided in the semiconductor region 32. , Other points are similar.

In the example shown in FIG. 6, the reflection unit 111 is provided near the center of the pixel 30c. The reflection portion 111 is formed in a rod shape in cross section from the back surface scattering portion 51 of the substrate to the front surface side reflection film 34 side. The reflecting portion 111 may be formed as a surface having a predetermined thickness in the semiconductor region 32, or may have a shape such as a cylinder or a polygonal prism.

By providing the reflecting portion 111 in the semiconductor region 32, as shown in the pixel 30c shown on the left side of FIG. 6, the incident light is reflected by the surface-side reflecting film 101 and reflected on the side surface of the semiconductor region 32. It goes to the reflection part 111. Then, it hits the reflection unit 111 and is further reflected by the reflection unit 111.

The light reflected by the reflecting unit 111 is further scattered by the back surface scattering unit 51 of the substrate or reflected by the antireflection film 35 on the back surface side, and is returned to the semiconductor region 32. Therefore, the structure can be prevented from being reflected by the surface-side reflective film 101 and coming out of the opening 52.

In this way, a hypotenuse is provided on at least one side of the surface-side reflective film 101, the incident light is hit and reflected on the hypotenuse, and the reflecting portion 111 is further provided in the semiconductor region 32. The amount of light that can be returned can be increased, and the sensitivity of the pixel 30c can be improved.

<Pixel configuration according to the fourth embodiment>
FIG. 7 is a cross-sectional view showing a configuration example of the pixel 30d according to the fourth embodiment of the present technology. In the pixel 30d shown in FIG. 7, the same parts as those of the pixel 30b according to the second embodiment shown in FIG. 5 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

The pixel 30d according to the fourth embodiment shown in FIG. 7 is configured to further include a reflection unit 112 and a reflection unit 113 in the semiconductor region 32 as compared with the pixel 30b according to the second embodiment. The difference is that it is the same in other respects.

The pixel 30c according to the third embodiment shown in FIG. 6 is configured to include one reflecting unit 111, but the pixel 30d according to the fourth embodiment shown in FIG. 7 has two pixels 30d. It is configured to include a reflecting unit 112 and a reflecting unit 113. As described above, a plurality of reflecting portions may be provided in the semiconductor region 32.

The pixel 30d shown in FIG. 7 includes a reflecting portion 112 on the left side of the opening 52 in the drawing, and a reflecting portion 113 on the right side of the opening 52 in the drawing. The reflecting portion 112 and the reflecting portion 113 are arranged at positions where the opening region of the opening 52 is not reduced.

The reflective unit 112 and the reflective unit 113 can each have the same configuration as the reflective unit 111 (FIG. 6). That is, the reflecting portion 112 and the reflecting portion 113 are formed on the front surface side reflecting film 34 side from the substrate back surface scattering portion 51, respectively, in a rod shape in cross section, and are formed as surfaces having a predetermined thickness in the semiconductor region 32. It may be shaped like a cylinder or a polygonal pillar.

By providing the reflecting

portions

112 and 113 in the semiconductor region 32, as shown in the pixel 30d shown on the left side of FIG. 7, the incident light is reflected by the slope of the surface side reflecting film 101 and the side surface of the semiconductor region 32. Is reflected by, and proceeds to the reflecting portion 112 side. Then, it is further reflected by the reflecting unit 112.

The light reflected by the reflecting unit 112 is further scattered by the substrate back surface scattering unit 51 or reflected by the back surface side reflecting film 35, and is returned to the semiconductor region 32. Therefore, the structure can be prevented from being reflected by the surface-side reflective film 101 and coming out of the opening 52.

In this case, the light can be confined in the region between the reflecting portion 112 and the side surface of the semiconductor region 32. Similarly, the reflecting portion 113 side also has a configuration in which light can be confined in the region between the reflecting portion 113 and the side surface of the semiconductor region 32.

In this way, the semiconductor region 32 is configured by providing an oblique side on at least one side of the surface-side reflective film 101 so that the incident light hits and reflects the oblique side, and further provides the reflecting

portions

112 and 113. The amount of light that can be returned to the inside can be increased, and the sensitivity of the pixel 30d can be improved.

<Pixel configuration according to the fifth embodiment>
FIG. 8 is a cross-sectional view showing a configuration example of the pixel 30e according to the fifth embodiment of the present technology. In the pixel 30e shown in FIG. 8, the same parts as those of the pixel 30a according to the first embodiment shown in FIG. 2 are designated by the same reference numerals, and the description thereof will be omitted as appropriate.

The pixel 30e according to the fifth embodiment shown in FIG. 8 is configured to include a scattering portion on the surface side of the semiconductor region 32 as compared with the pixel 30a according to the first embodiment. Different, the other points are similar.

The pixel 30e according to the fifth embodiment shown in FIG. 8 includes a substrate back surface scattering portion 51 on the incident surface side and a substrate surface scattering portion 131 on the wiring region 33 side. That is, the pixel 30e is configured to have scattering portions above and below the semiconductor region 32, respectively. The substrate surface scattering portion 131 is formed as a region having irregularities, similarly to the substrate back surface scattering portion 51. By providing the substrate back surface scattering portion 51 and the substrate surface scattering portion 131, as shown in the pixel 30e shown on the left side of FIG. 8, the incident light is scattered by the substrate back surface scattering portion 51 and enters the semiconductor region 32. Incident. Further, among the light incident on the semiconductor region 32, the light that has reached the substrate surface scattering portion 131 is scattered by the substrate surface scattering portion 131 and returned to the semiconductor region 32.

In this way, light can be confined in the semiconductor region 32 by repeating scattering and reflection between the substrate back surface scattering unit 51 and the substrate surface scattering unit 131. Therefore, the structure can prevent (reduce) the reflected light from escaping from the opening 52.

In this way, by providing the substrate back surface scattering portion 51 and the substrate surface scattering portion 131, the amount of light that can be retained in the semiconductor region 32 can be increased, and the sensitivity of the pixel 30e can be improved. it can.

Although FIG. 8 shows an example in which the substrate surface scattering portion 131 is formed from one side surface of the semiconductor region 32 to the other side surface (formed between the separation regions 38), the semiconductor region 32 is formed. It can be changed according to the pixel configuration, such as not being formed in the region where the gate of the transfer transistor (not shown) for reading the accumulated charge is formed. The same applies to other embodiments.

<Pixel configuration according to the sixth embodiment>
FIG. 9 is a cross-sectional view showing a configuration example of the pixel 30f according to the sixth embodiment of the present technology.

The pixel 30f according to the sixth embodiment shown in FIG. 9 includes the pixel 30b according to the second embodiment shown in FIG. 5 and the pixel 30e according to the fifth embodiment shown in FIG. It has a combined configuration. That is, the pixel 30f according to the sixth embodiment shown in FIG. 9 is configured to include the surface side reflective film 101 and the substrate surface scattering portion 131 on the surface side.

Since the pixel 30f according to the sixth embodiment includes the surface-side reflective film 101 having a slope like the pixel 30b according to the second embodiment, the reflected light of the 0th-order component escapes from the opening 52. It is possible to reduce such things as being lost. Further, since the pixel 30f according to the sixth embodiment includes the substrate surface scattering portion 131 like the pixel 30e according to the fifth embodiment, the light reaching the surface side of the semiconductor region 32 is emitted to the semiconductor region. Light can be returned into the semiconductor region 32 by being scattered within 32.

By providing the surface-side reflective film 101 and the substrate surface scattering portion 131 in this way, it is possible to reduce the possibility that the reflected light escapes from the opening 52, and the light is emitted into the semiconductor region 32. The amount of light that can be stopped can be increased. Therefore, the sensitivity of the pixel 30f can be improved.

<Pixel configuration according to the seventh embodiment>
FIG. 10 is a cross-sectional view showing a configuration example of a pixel 30 g according to a seventh embodiment of the present technology.

The pixel 30g according to the seventh embodiment has a configuration in which the pixel 30d according to the fourth embodiment and the pixel 30f according to the sixth embodiment are combined. That is, the pixel 30g according to the seventh embodiment includes the reflection unit 112 and the reflection unit 113, like the pixel 30d according to the fourth embodiment. Further, the pixel 30g according to the seventh embodiment includes the substrate surface scattering portion 131 like the pixel 30f according to the sixth embodiment.

Further, in the pixel 30g according to the seventh embodiment, the shape of the surface-side reflective film 101 is a shape including a triangular shape, and the reflecting portion 114 is provided at the apex of the triangular shape. The reflecting portion 114 is formed in the same shape as the reflecting portion 112 in the direction extending from the surface side reflecting film 101 toward the semiconductor region 32 side (from the lower side to the upper side in the drawing).

By providing the reflecting

portions

112, 113, 114 in this way, the amount of light that can be returned (fastened) into the semiconductor region 32 can be increased. Further, by providing the substrate surface scattering portion 131, the amount of light that can be retained in the semiconductor region 32 can be increased. Therefore, the sensitivity of the pixel 30 g can be improved.

<Pixel configuration according to the eighth embodiment>
FIG. 11 is a cross-sectional view showing a configuration example of the pixel 30h according to the eighth embodiment of the present technology.

The pixel 30h according to the eighth embodiment is provided with a substrate surface scattering portion 131 and a reflecting portion 114 on the surface side (wiring region 33 side), similarly to the pixel 30g according to the seventh embodiment. The reflective portion 114 shown in FIG. 11 showed a configuration in which the reflective portion 114 was provided on the rectangular surface-side reflective film 34, but the reflective portion 114 was provided on the surface-side reflective film 101 having a shape including a triangle. It may be configured.

The pixel 30h according to the eighth embodiment is different from the pixel 30 according to another embodiment in particular in the shape of the substrate back surface scattering portion 151 (in other embodiments, the substrate back surface scattering portion 51). The substrate back surface scattering portion 151 shown in FIG. 11 has a configuration in which it is not formed at the opening 52. Further, the semiconductor region 32 at the opening 52 has a tapered shape with engraving.

The opening 52 is filled with, for example, the same material as the protective film 36. In the pixel 30h shown in FIG. 11, a part of the semiconductor region 32 is filled with the same material as the protective film 36. A part of the semiconductor region 32 is a region located on the opening 52 side and having a triangular shape in cross section, for example. Here, it is described as the light refraction structure portion 152. The light refraction structure portion 152 can also be expressed as a large recess, the inside of the recess is filled with the same material as the protective film 36, and the outside of the recess is the semiconductor region 32.

At the boundary between the light refraction structure portion 152 and the semiconductor region 32, refraction occurs due to the difference in materials, and the optical path of the incident light can be bent. For example, as shown by an arrow in the pixel 30h shown on the left side of FIG. 11, the incident light is refracted at the boundary between the light refracting structure portion 152 and the semiconductor region 32, and in the example shown in FIG. 11, the semiconductor region 32 Proceed to the side of.

By providing the light refraction structure portion 152 in this way, the incident light can be refracted. By refracting the incident light, the incident light that directly reaches the surface-side reflective film 34 is reduced, and the reflected light of the 0th-order component can be reduced. Therefore, it is possible to reduce the light that escapes from the opening 52.

Further, by providing the reflecting portion 114, the light reflected (scattered) by the front surface side reflecting film 34 and the substrate back surface scattering portion 51 can hit the reflecting portion 114 and be prevented from exiting from the opening 52.

By providing the light refraction structure portion 152 in this way, it is possible to reduce the possibility that the reflected light escapes from the opening 52. Further, as in the other embodiments, the structure is such that the amount of light that can be retained in the semiconductor region 32 can be increased. Therefore, the sensitivity of the pixel 30h can be improved.

<Pixel configuration according to the ninth embodiment>
FIG. 12 is a cross-sectional view showing a configuration example of the pixel 30i according to the ninth embodiment of the present technology.

The pixel 30i according to the ninth embodiment is different in the shape of the reflecting portion 114 of the pixel 30h according to the eighth embodiment shown in FIG. 11, and is the same in other points. The reflective portion 115 of the pixel 30i according to the ninth embodiment is formed in a T shape. By providing a portion having a reflection structure in the direction parallel to the front surface side reflection film 34 (horizontal direction in the drawing) as the reflection portion 115, the reflection (scattering) is performed by the front surface side reflection film 34 and the substrate back surface scattering portion 51. It is possible to prevent the emitted light from hitting the reflecting portion 115 and exiting the opening 52.

The lateral reflection portion of the reflection portion 115 is provided directly below the opening 52, and is formed to have the same size as the width of the opening 52. Further, the side of the reflection portion 115 near the opening 52 is formed at a position away from the triangular apex of the light refraction structure portion 152.

By providing the light refracting structure portion 152 and the reflecting portion 115 in this way, it is possible to refract the incident light and reduce the incident light that directly reaches the surface side reflecting film 34, and the reflected light of the 0th-order component can be reduced. Can be reduced, and the light that escapes from the opening 52 can be reduced. Therefore, the sensitivity of the pixel 30i can be improved.

<Pixel configuration according to the tenth embodiment>
FIG. 13 is a cross-sectional view showing a configuration example of the pixel 30j according to the tenth embodiment of the present technology.

The pixel 30j according to the tenth embodiment has a configuration in which the waveguide 201 is added to the pixel 30b according to the second embodiment shown in FIG. The waveguide 201 is configured to be able to guide the incident light incident through the opening 52 to the semiconductor region 32.

Although the pixel 30j according to the tenth embodiment shown in FIG. 13 has a configuration including a surface-side reflective film 101 having an inclination, it may be configured to include a surface-side reflective film 34 having no inclination. ..

The waveguide 201 can be, for example, a core / clad type waveguide. When the core / clad type waveguide 201 is used, the portion corresponding to the core is the waveguide 201, the portion corresponding to the clad is the on-chip lens 37, and the refractive index of the material of the waveguide 201 and the material of the on-chip lens 37. Due to the difference, a material that causes total reflection is used. Specifically, a material is used in which the refractive index of the material forming the waveguide 201 is lower than the refractive index of the material forming the on-chip lens 37.

As the material of the waveguide 201, for example, SiN (silicon nitride), Ta2O5 (tantalum oxide), TiO2 (titanium oxide) and the like can be used.

The waveguide 201 is formed in a trapezoidal shape in cross section, and when the upper side is on the on-chip lens 37 side and the lower side is on the opening 52 side, the upper side is configured to have a length similar to the diameter of the on-chip lens 37. The lower side can be configured to have a length similar to the width of the opening 52.

As an example, the size of the opening 52 is set so that the following equation (1) is satisfied, and the size of the waveguide 201 is set according to the size of the opening 52.
θ ≧ (1/2) arctan (D / 2T) ・・・ (1)

In the formula (1), θ is an angle (inclination angle) formed by two sides of the triangular portion of the surface-side reflective film 101, as shown in FIG. Further, this angle θ is an angle that is (1/2) of the angle (= 2θ) formed by the incident light incident in the vertical direction and the reflected light reflected by the incident light hitting the surface-side reflective film 101. is there.

By setting the inclination angle of the surface-side reflective film 101 to an angle θ that satisfies the equation (1), when the light that hits the surface-side reflective film 101 is reflected, the reflected light is other than the opening 52. The region, in this case, the region where the back surface scattering portion 51 of the substrate and the back surface side reflective film 35 are located can be advanced.

Further, in the formula (1), D is the length of the portion opened as the opening 52. The length D can be the length of the lower side of the waveguide 201. Further, in the formula (1), T is the length from the opening 52 to the surface-side reflective film 101. In the example shown in FIG. 14, the length between the position on the boundary line between the back surface side reflective film 35 and the absorption film 91 of the opening 52 and the position of the apex of the triangle included in the front surface side reflective film 101 is defined as T. Shown. The length T can be rephrased as the length of the semiconductor region 32 in the vertical direction (depth direction) and the length of the photodiode in the depth direction.

By setting the length D that satisfies the equation (1), the width of the opening 52 and the length of the lower side of the waveguide 201 are set. The equation (1) is an example, and the scope of application of the present technology is not limited to the length D based on the equation (1).

The waveguide 201 is arranged as shown in FIG. 15 when the pixel 30j is viewed from above. In FIG. 15, the outer quadrangle represents one pixel 30j, and the inner quadrangle with diagonal lines represents the lower surface (the surface on the opening 52 side) of the waveguide 201. Since the 1 pixel 30j is separated by the separation region 38, the outer quadrangle in the figure represents the separation region 38, and the description will be continued assuming that the region surrounded by the separation region 38 is the 1 pixel region.

FIG. 15A shows a case where the quadrangle of the pixel 30j and the quadrangle of the waveguide 201 are oriented in the same direction. As shown in FIG. 15A, the waveguide 201 has the same shape as the pixel 30j and is formed at a position where the sides are arranged in parallel.

FIG. 15B shows a case where the quadrangle of the waveguide 201 is arranged at a position inclined by 45 degrees with respect to the quadrangle of the pixel 30j. As shown in FIG. 15B, the waveguide 201 has the same shape (quadrangle) as the pixel 30j, but is arranged at a position where the sides intersect at 45 degrees.

For example, as shown in FIG. 15A, when the pixels 30j and the waveguide 201 are arranged in the same direction, the incident light incident on one side of the waveguide 201 is the side as shown by the arrow in the figure. It corresponds to the side (side surface of the semiconductor region 32) of the pixel 30j arranged in parallel with. Then, the light that hits the side of the pixel 30j is reflected by the side surface of the semiconductor region 32 and returned to the inside of the semiconductor region 32.

Similarly, as shown in FIG. 15B, when the waveguide 201 is arranged at an angle of 45 degrees with respect to the pixel 30j, the incident light incident on one side of the waveguide 201 is as shown by the arrow in the figure. , Corresponds to the side (side surface of the semiconductor region 32) of the pixel 30j arranged at a position intersecting the side at 45 degrees. Then, the light that hits the side of the pixel 30j hits the other side (the side surface of the semiconductor region 32) of the pixel 30j. In this way, the light that hits the side of the pixel 30j twice is returned to the semiconductor region 32.

The position of the waveguide 201 with respect to the pixel 30j may be other than the example shown in FIG. Further, the shape of the waveguide 201 does not have to be a quadrangular shape when viewed from above, and may be a polygonal shape or a circular shape other than the quadrangular shape.

Further, here, the case where the waveguide 201 is used will be described as an example, but a member having the same function as the waveguide may be used instead of the waveguide 201. In the following description, the case where the waveguide 201 is used will be described as an example, but a member having the same function as the waveguide may be used instead of the waveguide 201.

For example, a diffraction grating may be used instead of the waveguide 201. The diffraction grating is composed of a member having a periodic structure, for example, using a material having a refractive index lower than that of the on-chip lens 37.

For example, a filter called a plasmon filter or the like may be used as the diffraction grating. The plasmon filter is a filter using a plasmon resonance pair. The plasmon filter is used as a filter that transmits light of a predetermined wavelength.

The plasmon filter is sometimes used as a color filter. In the above-described embodiment, the color filter is not shown, but the pixel 30 provided with the color filter can of course be used. Further, as the color filter, a diffraction grating-shaped filter such as a plasmon filter that selectively transmits light having a predetermined frequency can also be used. Further, the pixel 30 having a configuration in which the diffraction grating used as such a color filter is provided as the waveguide 201 may be used.

Further, as shown in FIG. 16, a color filter may be provided on the waveguide 201. In the pixel 30j'shown in FIG. 16, a color filter layer 221 is provided between the on-chip lens 37 and the waveguide 201. In this way, the color filter layer 221 may be provided.

The material constituting the color filter layer 221 is formed in the shape of the waveguide 201, and the color filter layer 221 is provided with the function of the waveguide 201, in other words, the waveguide 201 is provided with the function of the color filter layer 221. It can also be configured. That is, in the pixel 30j shown in FIG. 13, the waveguide 201 may be configured to have a function as a color filter. This also applies to the embodiments described below.

The configuration in which the color filter layer 221 is provided can be applied to the first to ninth embodiments described above, and can also be applied to each embodiment described below.

By providing the waveguide 201 in this way, the incident light can be guided to the semiconductor region 32 through the opening 52, and more incident light can be incidented on the semiconductor region 32. Further, as in the above-described embodiment, the amount of reflected light emitted from the opening 52 can be reduced, and the amount of light confined in the semiconductor region 32 can be increased. Therefore, the sensitivity of the pixel 30j can be improved.

<Pixel configuration according to the eleventh embodiment>
FIG. 17 is a cross-sectional view showing a configuration example of the pixel 30k according to the eleventh embodiment of the present technology.

The pixel 30k according to the eleventh embodiment has a configuration in which the waveguide 201 is added to the pixel 30c according to the third embodiment shown in FIG. The waveguide 201 has a configuration capable of guiding the incident light incident through the opening 52 to the semiconductor region 32, similarly to the waveguide 201 of the pixel 30j according to the tenth embodiment shown in FIG. ing.

The incident light guided to the opening 52 by the waveguide 201 is scattered by the substrate back surface scattering portion 51 and incident on the semiconductor region 32, and is reflected by the reflection portion 111 and stays in the semiconductor region 32. In addition, some light is reflected by the surface-side reflective film 101 and returns to the semiconductor region 32, so that the incident light can be retained in the semiconductor region 32.

By providing the waveguide 201 in this way, more incident light can be guided to the semiconductor region 32 through the opening 52. Further, as in the above-described embodiment, the amount of reflected light emitted from the opening 52 can be reduced, and the amount of light confined in the semiconductor region 32 can be increased. Therefore, the sensitivity of the pixel 30k can be improved.

<Pixel configuration according to the twelfth embodiment>
FIG. 18 is a cross-sectional view showing a configuration example of a pixel 30 m according to a twelfth embodiment of the present technology.

The pixel 30m according to the twelfth embodiment has a configuration in which the waveguide 201 is added to the pixel 30d according to the fourth embodiment shown in FIG. The waveguide 201 has a configuration capable of guiding the incident light incident through the opening 52 to the semiconductor region 32, similarly to the waveguide 201 of the pixel 30j according to the tenth embodiment shown in FIG. ing.

The incident light guided to the opening 52 by the waveguide 201 is scattered by the substrate back surface scattering portion 51 and incident on the semiconductor region 32, and is reflected by the reflecting portion 112 and the reflecting portion 113 and enters the semiconductor region 32. Stay. In addition, some light is reflected by the surface-side reflective film 101 and returns to the semiconductor region 32, so that the incident light can be retained in the semiconductor region 32.

By providing the waveguide 201 in this way, more incident light can be guided to the semiconductor region 32 through the opening 52. Further, as in the above-described embodiment, the amount of reflected light emitted from the opening 52 can be reduced, and the amount of light confined in the semiconductor region 32 can be increased. Therefore, the sensitivity of the pixel 30 m can be improved.

<Pixel configuration according to the thirteenth embodiment>
FIG. 19 is a cross-sectional view showing a configuration example of the pixel 30n according to the thirteenth embodiment of the present technology.

The pixel 30n according to the thirteenth embodiment has a configuration in which the waveguide 201 is added to the pixel 30e according to the fifth embodiment shown in FIG. The waveguide 201 has a configuration capable of guiding the incident light incident through the opening 52 to the semiconductor region 32, similarly to the waveguide 201 of the pixel 30j according to the tenth embodiment shown in FIG. ing.

The incident light guided to the opening 52 by the waveguide 201 is scattered by the substrate back surface scattering portion 51 and is incident on the semiconductor region 32, and the light reaching the front surface side is scattered by the substrate surface scattering portion 131. It is returned to the semiconductor region 32 by being reflected by the surface-side reflective film 34. Therefore, the incident light can be limited to the semiconductor region 32.

By providing the waveguide 201 in this way, more incident light can be guided to the semiconductor region 32 through the opening 52. Further, as in the above-described embodiment, the amount of reflected light emitted from the opening 52 can be reduced, and the amount of light confined in the semiconductor region 32 can be increased. Therefore, the sensitivity of the pixel 30n can be improved.

<Pixel configuration according to the 14th embodiment>
FIG. 20 is a cross-sectional view showing a configuration example of the pixel 30p according to the 14th embodiment of the present technology.

The pixel 30p according to the fourteenth embodiment has a configuration in which the waveguide 201 is added to the pixel 30f according to the sixth embodiment shown in FIG. The waveguide 201 has a configuration capable of guiding the incident light incident through the opening 52 to the semiconductor region 32, similarly to the waveguide 201 of the pixel 30j according to the tenth embodiment shown in FIG. ing.

The incident light guided to the opening 52 by the waveguide 201 is scattered by the substrate back surface scattering portion 51 and is incident on the semiconductor region 32, and the light reaching the front surface side is scattered by the substrate surface scattering portion 131. It is returned to the semiconductor region 32 by being reflected by the surface-side reflective film 101. Therefore, the incident light can be limited to the semiconductor region 32.

By providing the waveguide 201 in this way, more incident light can be guided to the semiconductor region 32 through the opening 52. Further, as in the above-described embodiment, the amount of reflected light emitted from the opening 52 can be reduced, and the amount of light confined in the semiconductor region 32 can be increased. Therefore, the sensitivity of the pixel 30p can be improved.

<Pixel configuration according to the fifteenth embodiment>
FIG. 21 is a cross-sectional view showing a configuration example of the pixel 30q according to the fifteenth embodiment of the present technology.

The pixel 30q according to the fifteenth embodiment has a configuration in which the waveguide 201 is added to the pixel 30g according to the seventh embodiment shown in FIG. The waveguide 201 has a configuration capable of guiding the incident light incident through the opening 52 to the semiconductor region 32, similarly to the waveguide 201 of the pixel 30j according to the tenth embodiment shown in FIG. ing.

The incident light guided to the opening 52 by the waveguide 201 is scattered by the substrate back surface scattering portion 51 and is incident on the semiconductor region 32, and the light reaching the front surface side is scattered by the substrate surface scattering portion 131. It is returned to the semiconductor region 32 by being reflected by the surface-side reflective film 101.

Further, the light incident or reflected in the semiconductor region 32 is reflected by the reflecting portion 112, the reflecting portion 113, and the reflecting portion 114, and stays in the semiconductor region 32.

Since the shape of the surface-side reflective film 101 is a shape including the hypotenuse, it is possible to reduce the reflected light of the 0th-order component and reduce the light that escapes from the opening 52. From these things, the incident light can be kept longer in the semiconductor region 32.

By providing the waveguide 201 in this way, more incident light can be guided to the semiconductor region 32 through the opening 52. Further, as in the above-described embodiment, the amount of reflected light emitted from the opening 52 can be reduced, and the amount of light confined in the semiconductor region 32 can be increased. Therefore, the sensitivity of the pixel 30q can be improved.

<Pixel configuration according to the 16th embodiment>
FIG. 22 is a cross-sectional view showing a configuration example of the pixel 30r according to the 16th embodiment of the present technology.

The pixel 30r according to the sixteenth embodiment has a configuration in which the waveguide 201 is added to the pixel 30h according to the eighth embodiment shown in FIG. The waveguide 201 has a configuration capable of guiding the incident light incident through the opening 52 to the semiconductor region 32, similarly to the waveguide 201 of the pixel 30j according to the tenth embodiment shown in FIG. ing.

Since the light refraction structure portion 152 is formed, the incident light guided to the opening 52 by the waveguide 201 is refracted at the boundary portion between the light refraction structure portion 152 and the semiconductor region 32, and is incident on the semiconductor region 32. ..

The light incident on the semiconductor region 32 and reaching the surface side is returned to the semiconductor region 32 by being scattered by the substrate surface scattering portion 131 or reflected by the surface side reflective film 34. In addition, some light is reflected by the reflecting unit 114, and the structure is such that the light easily stays in the semiconductor region 32. The pixel 30r according to the sixteenth embodiment also has a structure capable of retaining the incident light in the semiconductor region 32.

By providing the waveguide 201 in this way, more incident light can be guided to the semiconductor region 32 through the opening 52. Further, as in the above-described embodiment, the amount of reflected light emitted from the opening 52 can be reduced, and the amount of light confined in the semiconductor region 32 can be increased. Therefore, the sensitivity of the pixel 30r can be improved.

<Pixel configuration according to the 17th embodiment>
FIG. 23 is a cross-sectional view showing a configuration example of the pixels 30s according to the seventeenth embodiment of the present technology.

The pixel 30s according to the seventeenth embodiment has a configuration in which the waveguide 201 is added to the pixel 30i according to the ninth embodiment shown in FIG. The waveguide 201 has a configuration capable of guiding the incident light incident through the opening 52 to the semiconductor region 32, similarly to the waveguide 201 of the pixel 30j according to the tenth embodiment shown in FIG. ing.

The light incident on the semiconductor region 32 and reaching the surface side is returned to the semiconductor region 32 by being scattered by the substrate surface scattering portion 131 or reflected by the surface side reflective film 34. In addition, some light is reflected by the reflecting unit 115, and the structure is such that the light easily stays in the semiconductor region 32. The pixel 30s according to the seventeenth embodiment also has a structure capable of retaining the incident light in the semiconductor region 32.

By providing the waveguide 201 in this way, more incident light can be guided to the semiconductor region 32 through the opening 52. Further, as in the above-described embodiment, the amount of reflected light emitted from the opening 52 can be reduced, and the amount of light confined in the semiconductor region 32 can be increased. Therefore, the sensitivity of the pixels 30s can be improved.

<Pixel configuration according to the eighteenth embodiment>
FIG. 24 is a cross-sectional view showing a configuration example of the pixel 30t according to the eighteenth embodiment of the present technology.

The pixel 30t according to the eighteenth embodiment includes the waveguide 301 corresponding to the waveguide 201 like the pixel 30j according to the tenth embodiment shown in FIG. 13, but its shape and shape are formed. The position is different.

The waveguide 301 is configured to be able to guide the incident light incident through the opening 52 to the semiconductor region 32, and thus guides the pixels 30j according to the tenth embodiment shown in FIG. It is the same as the waveguide 201.

The waveguide 301 is formed in a parallelogram in cross section, and when the upper side is the on-chip lens 37 side and the lower side is the opening 52 side, the upper side and the lower side are about the same length as the width of the opening 52. Can be configured with.

The central position P2 of the upper side of the waveguide 301 and the central position P1 of the on-chip lens 37 are in a deviated positional relationship. In the example shown in FIG. 24, the central position P2 of the upper side of the waveguide 301 is located at a position shifted to the left side of the central position P1 of the on-chip lens 37.

The central position P3 of the lower side of the waveguide 301 and the central position P1 of the on-chip lens 37 are also in a deviated positional relationship. In the example shown in FIG. 24, the center position P3 of the lower side of the waveguide 301 is located at a position shifted to the right side of the center position P1 of the on-chip lens 37.

Since the opening 52 is opened according to the position of the lower side of the waveguide 301, the center position of the opening 52 is also shifted to the right side from the center position P1 of the on-chip lens 37.

The waveguide 301 is formed in a shape inclined in an oblique direction. In the example shown in FIG. 24, when the lower side of the waveguide 301 is used as a reference, the shape is formed so as to be inclined in the upper left diagonal direction.

When the waveguide 301 is formed in an inclined state in this way, the incident light travels to the pixel 30t shown on the left side of FIG. 24 as shown by an arrow. The incident light incident on the waveguide 301 hits the right side surface of the semiconductor region 32 in the drawing and is reflected. As shown in FIG. 24, when the waveguide 301 is formed in a state of being inclined in the upper left oblique direction, more light travels to the right side surface of the semiconductor region 32 in the drawing.

By configuring the waveguide 301 so that light travels on the right or left side surface of the semiconductor region 32, it is possible to reduce the amount of light that hits the surface-side reflective film 34 vertically, that is, the light of the so-called 0th-order component. Therefore, it is possible to reduce the amount of light that is reflected by the surface-side reflective film 34 and escapes from the opening 52, that is, the light of the so-called zero-order component.

Therefore, by providing the waveguide 301, more incident light can be guided to the semiconductor region 32 through the opening 52, and the amount of reflected light emitted from the opening 52 can be reduced. it can. Therefore, the amount of light confined in the semiconductor region 32 can be increased, and the sensitivity of the pixel 30t can be improved.

The inclination angle (inclination angle) of the waveguide 301 may be different depending on the position of the pixel 30t in the pixel array unit 10. For example, when the pixel array unit 10 is divided into a central region and a peripheral region, the tilt angle of the pixels 30t arranged in the central region may be formed to be larger than the tilt angle of the pixels 30t arranged in the peripheral region. ..

Further, among the pixels 30t arranged in the peripheral region, the pixel array unit 10 is divided into a peripheral region on the right side, a peripheral region on the left side, a peripheral region on the upper side, and a peripheral region on the lower side, and the directions are inclined according to the respective positions. May be different.

Further, since the pixels 30t arranged in the peripheral region of the pixel array unit 10 have a large amount of incident light from an oblique direction, the configuration may not include the waveguide 301. In this case, the waveguide 301 can be formed in the pixel 30t located in the central region of the pixel array unit 10, and the waveguide 301 can not be formed in the pixel 30t located in the peripheral region of the pixel array portion 10. .. In this case, the inclination angle of the waveguide 301 is reduced from the central region to the peripheral region, and the waveguide 301 is not formed in the region where the inclination angle is 90 degrees (close to). Can be done.

The pixel 30t shown in FIG. 24 has a configuration in which the substrate back surface scattering portion 109 is not provided. However, for example, as in the pixel 30a according to the first embodiment shown in FIG. 4, the substrate back surface scattering portion 51 is provided. It may be provided.

Further, as in the pixel 30b according to the second embodiment shown in FIG. 5, the surface side reflective film 101 having a shape having a slope may be provided. Further, as in the pixel 30f according to the sixth embodiment shown in FIG. 9, the configuration may include the substrate surface scattering portion 131. As described above, the pixel 30t according to the eighteenth embodiment can be configured in combination with the pixel 30 according to another embodiment.

That is, the pixel 30t according to the eighteenth embodiment can be configured in combination with the pixels a to i according to the first to ninth embodiments.

Further, depending on the position in the pixel array unit 10, any of the pixels a to t according to the first to eighteenth embodiments can be applied.

<Pixel configuration according to the 19th embodiment>
FIG. 25 is a cross-sectional view showing a configuration example of the pixel 30u according to the 19th embodiment of the present technology.

The pixel 30u according to the nineteenth embodiment is different in that the reflecting portion 311 is added to the pixel 30t according to the eighteenth embodiment shown in FIG. 24, and the other points are the same. is there.

In the example shown in FIG. 25, the reflection portion 311 is formed on the left side of the opening 52 (lower side of the waveguide 301) in the drawing. The reflection unit 311 is formed at a position that does not interfere with the path of the incident light input via the waveguide 301. The reflecting portion 311 is formed in a rod shape in a cross section, for example, like the reflecting portion 111 provided in the pixel 30c according to the third embodiment shown in FIG. The reflecting portion 311 may be formed as a surface having a predetermined thickness in the semiconductor region 32 in the semiconductor region 32, or may have a shape such as a cylinder or a polygonal prism.

By providing the reflecting portion 311 in the semiconductor region 32, as shown in the pixel 30u shown on the left side of FIG. 25, the incident light hits the right side surface of the semiconductor region 32 and travels toward the surface side reflecting film 34 side. Then, it is reflected by the surface-side reflective film 34, reflected on the side surface of the semiconductor region 32, hits the reflecting portion 311 and is further reflected by the reflecting portion 311.

The light reflected by the reflecting unit 311 travels to the side surface side of the semiconductor region 32 again and is reflected. Light can be reflected a plurality of times between the side surface of the semiconductor region 32 and the reflecting portion 311.

By providing the waveguide 301 in this way, more incident light can be guided to the semiconductor region 32 through the opening 52. Further, by providing the reflecting portion 311, the amount of light that can be kept in the semiconductor region 32 can be increased, and the sensitivity of the pixel 30u can be improved.

<Pixel configuration according to the twentieth embodiment>
FIG. 26 is a cross-sectional view showing a configuration example of the pixel 30v according to the twentieth embodiment of the present technology.

The pixel 30v according to the twentieth embodiment is different from the pixel 30t according to the eighteenth embodiment shown in FIG. 24 in that a reflection unit 312 and a reflection unit 313 are added. The points are similar.

The reflecting portion 312 is formed in the semiconductor region 32 from the back surface side to the front surface side (from top to bottom in the figure), and the reflecting portion 313 is formed in the semiconductor region 32 from the front surface side to the back surface side (from the bottom in the figure). It is formed in the direction of (upper). Further, the reflecting portion 313 is formed at a position between the reflecting portion 312 and the side surface of the semiconductor region 32. Further, the side surface of the semiconductor region is a surface facing the side surface on the side where more light is collected via the waveguide 301 (the side surface on the right side of the semiconductor region 32 in FIG. 26).

By providing the waveguide 301, the reflection portion 312, and the reflection portion 313 in the semiconductor region 32, the incident light is directed to the right side surface side of the semiconductor region 32 as shown in the pixel 30v shown on the left side of FIG. 26. It advances, is reflected, and proceeds to the surface side reflective film 34 side. Then, it is reflected by the surface-side reflective film 34, reflected by the reflecting portion 313, and reflected by the reflecting portion 312.

The light reflected by the reflecting portion 312 is reflected by the back surface side reflecting film 35, reflected by the side surface of the semiconductor region 32, and hits the reflecting portion 313. In this way, light is reflected a plurality of times between the side surface of the semiconductor region 32 and the reflection unit 312, between the reflection unit 312 and the reflection unit 313, and between the reflection unit 313 and the side surface of the semiconductor region 32. Can be.

By providing the waveguide 301 in this way, more incident light can be guided to the semiconductor region 32 through the opening 52. Further, by providing the reflecting portion 312 and the reflecting portion 313, the amount of light that can be retained in the semiconductor region 32 can be increased, and the sensitivity of the pixel 30v can be improved.

<Pixel configuration according to the 21st embodiment>
FIG. 27 is a cross-sectional view showing a configuration example of the pixel 30w according to the 21st embodiment of the present technology.

The pixel 30w according to the 21st embodiment has a configuration in which a substrate back surface scattering portion 321 and a substrate surface scattering portion 322 are added to the pixel 30u according to the 19th embodiment shown in FIG. 25. Different, the other points are similar.

The substrate back surface scattering portion 321 is between the reflection portion 311 and the side surface of the semiconductor region 32, and is formed in a region other than the portion where the waveguide 301 is located. Further, the substrate surface scattering portion 322 is on the front surface side (wiring region 33 side), and like the substrate back surface scattering portion 321, between the reflection portion 311 (a position assumed to be extended) and the side surface of the semiconductor region 32. It is formed.

By providing the substrate back surface scattering unit 321 and the substrate surface scattering unit 322, the light that has reached the substrate back surface scattering unit 321 or the substrate surface scattering unit 322 can be scattered. Similar to the pixel 30e according to the form, the configuration can be such that light can be confined in the semiconductor region 32.

By providing the waveguide 301 in this way, more incident light can be guided to the semiconductor region 32 through the opening 52. Further, by providing the reflecting portion 311, the substrate back surface scattering portion 321 and the substrate surface scattering portion 322, the incident light can be returned to the semiconductor region 32 and the amount of light that can be retained can be increased. Therefore, the sensitivity of the pixel 30w can be improved.

The substrate back surface scattering unit 321 and the substrate surface scattering unit 322 are provided between one side surface of the semiconductor region 32 and the other side surface, for example, as in the pixel 30a according to the first embodiment shown in FIG. It may be configured to be.

As described above, the first to 21st embodiments can be applied in combination. Further, the pixel array unit 10 may be configured such that among the pixels 30a to 30w according to the first to 21st embodiments, the pixels 30 according to different embodiments are mixed.

<Application example>
The pixels 30a to 30w according to the first to 21st embodiments described above have been described by exemplifying a case where the pixels 30a to 30w are applied to an image pickup device (hereinafter, appropriately referred to as a normal pixel) for imaging a subject. In addition to normal pixels, for example, it can be applied to pixels as described below.

The pixels 30a to 30w according to the first to 21st embodiments described above can also be applied to pixels for distance measurement (hereinafter, appropriately referred to as distance measurement pixels). FIG. 28 shows a configuration when the pixel 30j according to the tenth embodiment is applied to the distance measuring pixel. The ranging pixel shown in FIG. 28 has two transfer transistors TRG1 and TRG2 as transfer gates and two stray diffusion regions FD1 and FD2 as charge storage units for one photodiode PD. It shows a so-called two-tap pixel structure in which the electric charge generated by the photodiode PD is distributed to two floating diffusion regions FD1 and FD2.

A surface-side reflective film 101 is formed between the two transfer transistors TRG1 and TRG2. When viewed in a plan view, as shown in FIG. 29, the surface-side reflective film 101 is formed near the center of the photodiode PD.

FIG. 29 is a plan view showing an arrangement example of the transistor of the pixel 30j shown in FIG. 28. As shown in FIG. 29, the photodiode PD is formed in the N-type semiconductor region 32 in the central region of the rectangular pixel 30j. A surface-side reflective film 101 is formed in the center of the photodiode PD.

The transfer transistor TRG1, the switching transistor FDG1, the reset transistor RST1, the amplification transistor AMP1, and the selection transistor SEL1 are linearly arranged along a predetermined side of four sides of the rectangular pixel 30j outside the photodiode PD. The transfer transistor TRG2, the switching transistor FDG2, the reset transistor RST2, the amplification transistor AMP2, and the selection transistor SEL2 are arranged linearly along the other side of the four sides of the rectangular pixel 30.

Further, the charge discharge transistor OFG is arranged on a side different from the two sides of the pixel 30 on which the transfer transistor TRG, the switching transistor FDG, the reset transistor RST, the amplification transistor AMP, and the selection transistor SEL are formed.

The arrangement of the pixel circuits shown in FIG. 29 is not limited to this example, and may be other arrangements. Further, here, the configuration when the pixel 30j according to the tenth embodiment is applied to the distance measuring pixel is shown, but such a configuration is also shown when another embodiment is applied as the distance measuring pixel. Arrangements can be applied.

FIG. 30 shows a configuration when the pixel 30w according to the nineteenth embodiment is applied to the distance measuring pixel. Since the distance measuring pixel shown in FIG. 30 also illustrates a pixel that performs distance measuring by a two-tap method, one photodiode PD has two transfer transistors TRG1 and TRG2 as transfer gates, and has an electric charge. It has two floating diffusion regions FD1 and FD2 as storage portions.

As shown in FIG. 30, when the waveguide 301 is formed in an inclined state, the reflection portion 311 is provided at a position avoiding the opening 52 as shown in FIG. 31.

Here, the configuration when the pixel 30w according to the 19th embodiment is applied to the distance measuring pixel is shown, but such an arrangement is also used when the other embodiment is applied as the distance measuring pixel. It can be applied.

When the configuration is provided with the floating diffusion region FD as in the pixels shown in FIGS. 29 to 31, it is necessary to prevent the stray light component from entering the floating diffusion region FD. FIG. 32 shows a configuration when the pixel 30j according to the tenth embodiment is applied to a normal pixel having a floating diffusion region FD. The pixel 30j shown in FIG. 32 is provided with a floating diffusion region FD on the lower right side in the drawing, and is provided with a transfer gate TRG for transferring charges from the photodiode PD to the floating diffusion region FD.

When the floating diffusion region FD is formed on the right side in the drawing as shown in FIG. 32, the surface side reflective film 101 having an inclination that the floating diffusion region FD side becomes higher is formed. The surface-side reflective film 101 having such an inclination is formed near the center of the photodiode PD in a plane, as in the case shown in FIG. 29, for example.

The inclined surface of the surface-side reflective film 101 is formed so as not to face the floating diffusion region FD side. Therefore, as shown in FIG. 32, the incident light hits the inclined surface of the surface-side reflective film 101 and travels to the side surface of the semiconductor region 32 opposite to the side on which the floating diffusion region FD is formed. By forming the surface-side reflective film 101 so that the inclined surface does not face the floating diffusion region FD, it is possible to reduce the amount of light traveling toward the floating diffusion region FD.

FIG. 33 shows a configuration when the pixel 30t according to the eighteenth embodiment of the present technology is applied to a normal pixel having a floating diffusion region FD. The pixel 30t shown in FIG. 33 is provided with a floating diffusion region FD on the lower left side in the drawing, and is provided with a transfer gate TRG for transferring charges from the photodiode PD to the floating diffusion region FD.

When the floating diffusion region FD is formed on the left side in the figure as shown in FIG. 33, the reflecting portion 351 is added to the floating diffusion region FD side (nearby). The reflective portion 351 is formed so as to extend in the vertical direction from the surface-side reflective film 34. The reflecting portion 351 and the surface side reflecting film 34 may be integrally formed, or may be formed as a separate body, and the reflecting portion 351 and the surface side reflecting film 34 may not be in contact with each other.

The surface-side reflective film 34 having such a reflective portion 351 is formed near the center of the photodiode PD, as in the case shown in FIG. 29 (the portion described as the front-side reflective film 101 in FIG. 30), for example. The reflection unit 351 may be configured to surround the floating diffusion region FD.

By providing the reflecting portion 351, as shown in FIG. 33, the incident light is opposed to the right side surface of the semiconductor region 32 in the drawing, in other words, the side on which the floating diffusion region FD is formed, by the waveguide 301. Proceed to the side to do. Then, the incident light is reflected by the side surface of the semiconductor region 32, hits the surface side reflective film 34, is reflected, and hits the reflecting portion 351. If there is no reflecting portion 351, the reflected light advances to the floating diffusion region FD, but by providing the reflecting portion 351, it is possible to prevent the reflected light from advancing to the floating diffusion region FD.

The pixels 30a to 30w according to the first to 21st embodiments can also be applied to the pixels provided with the memory. FIG. 34 is a diagram showing a configuration of pixels 30x to which the present technology is applied to the distance measuring pixels that are pixels having a memory and performing distance measuring. Further, the pixel 30x indicates a case where the distance measuring pixel is a 2-tap method.

The pixel 30x shown in FIG. 34 includes a waveguide 201 and a light refraction structure portion 152, similarly to the pixel 30r shown in FIG. The semiconductor substrate 31 on the wiring region 33 side of the pixel 30x has a floating diffusion region FD1, a memory region Mem1, a transfer gate TRG1, a transfer gate TRG1', and a floating diffusion region FD2, a memory area Mem2, a transfer gate TRG2, and a transfer gate TRG2'. Is provided.

The electric charge from the photodiode PD is transferred to the memory area Mem1 by the transfer gate TRG1. The electric charge transferred to the memory area Mem1 is transferred to the floating diffusion area FD1 by the transfer gate TRG1'. Similarly, the charge from the photodiode PD is transferred to the memory area Mem2 by the transfer gate TRG2. The electric charge transferred to the memory area Mem2 is transferred to the floating diffusion area FD2 by the transfer gate TRG2'.

The transfer gate TRG1 and the transfer gate TRG2 are each formed of (gates) vertical transistors. As shown in FIG. 34, the gate of the vertical transistor is a gate having vertical wiring provided in the vertical direction in the drawing and wiring provided close to the semiconductor region 32 constituting the photodiode PD. Is. Although FIG. 34 shows an example in which the semiconductor region 32 is provided close to the semiconductor region 32, the configuration may be such that the semiconductor region 32 is provided.

In this way, when the memory area Mem and the floating diffusion area FD are provided, the reflection unit 361 is placed on the memory area Mem and the floating diffusion area FD so that the stray light component does not enter the memory area Mem and the floating diffusion area FD. It is formed. The reflection portion 361 is formed at the boundary between the semiconductor region 32 and the semiconductor substrate 31. Further, as shown in FIG. 35, the reflection portion 361 is a region avoiding the gate TGR1 and the gate TGR2 of the vertical transistor in a plane, and is formed in the semiconductor region 32.

In the configuration shown in FIG. 34, if there is light that has passed through the area where the memory area Mem or the like is provided and reaches the wiring area 33 side, the light is reflected and the memory area Mem or the like is again used. If it returns to the area where is provided, a stray light component will be generated. When the configuration is as shown in FIG. 34, the surface-side reflective film 34 and the film corresponding to the surface-side reflective film 101 are not provided in the wiring region 33.

By providing the reflecting portion 361, as shown in FIG. 34, the incident light is refracted by the light refracting structure portion 152, travels toward the side surface of the semiconductor region 32, and is reflected. The reflected light reflected on the side surface of the semiconductor region 32 hits the reflecting portion 361 and is reflected. Since the light is reflected by the reflection unit 361, it is possible to prevent the light from entering the memory area Mem or the floating diffusion area FD arranged under the reflection unit 361.

FIG. 36 is a pixel provided with a memory like the pixel 30x shown in FIG. 34, and is a diagram showing a configuration example of the pixel 30y when the present technology is applied to the distance measuring pixel for performing distance measurement. Further, the pixel 30y shown in FIG. 36 shows a case where the pixel 30y is a distance measuring pixel in a two-tap method like the pixel 30x.

The pixel 30y shown in FIG. 36 includes a waveguide 301 and a reflection unit 311 like the pixel 30w shown in FIG. 26. Further, the pixels 30y are the same as the pixels 30x, on the semiconductor substrate 31 on the wiring area 33 side, the floating diffusion area FD1, the memory area Mem1, the transfer gate TRG1, the transfer gate TRG1', and the floating diffusion area FD2, the memory area Mem2, and the transfer gate. It is equipped with TRG2 and transfer gate TRG2'.

When the waveguide 301 is provided, as in the case where the waveguide 201 is provided (similar to the pixel 30x), the memory area Mem and the floating diffusion are prevented so that the stray light component does not enter the memory area Mem and the floating diffusion area FD. A reflection portion 361 is formed on the region FD. Further, as shown in FIG. 35, the reflection portion 361 is a region avoiding the gate TGR1 and the gate TGR2 of the vertical transistor in a plane, and is formed in the semiconductor region 32.

By providing the reflecting portion 361, as shown in FIG. 36, the incident light is guided to the waveguide 301, travels in the side surface direction of the semiconductor region 32, and is reflected. The reflected light reflected on the side surface of the semiconductor region 32 hits the reflecting portion 361 and is reflected. Since the light is reflected by the reflection unit 361, it is possible to prevent the light from entering the memory area Mem or the floating diffusion area FD arranged under the reflection unit 361.

It should be noted that SPAD (single photon avalanche diode) can be used as the distance measuring pixel, and this technology can be applied to SPAD.

According to this technology, it is possible to collect more incident light on the photodiode. Further, the light incident on the photodiode can be retained inside the photodiode, and the light that escapes from the photodiode can be reduced. Therefore, QE loss (loss of quantum efficiency) can be reduced. Further, by providing the waveguide, it is possible to configure the structure so that light can pass through the opening even if the height is low, so that the height of the pixel can be reduced and the size of the pixel can be reduced.

<Example of application to camera>
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 image pickup device mounted on an image pickup device such as a camera.

FIG. 37 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 image pickup element 1002, an image pickup control unit 1003, a lens drive unit 1004, an image processing unit 1005, an operation input unit 1006, a frame memory 1007, a display unit 1008, and the like. A recording unit 1009 is provided.

The lens 1001 is a photographing lens of the camera 1000. The lens 1001 collects light from the subject and causes the light to be incident on the image pickup device 1002 described later to form an image of the subject.

The image sensor 1002 is a semiconductor element that captures light from a subject focused 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 the signal.

The image pickup control unit 1003 controls the image pickup in the image pickup device 1002. The image pickup control unit 1003 controls the image pickup device 1002 by generating a control signal and outputting the control signal to the image pickup device 1002. Further, the image pickup control unit 1003 can perform autofocus on the camera 1000 based on the image signal output from the image pickup device 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) in which the image plane phase difference is detected by the phase difference pixels arranged in the image sensor 1002 to detect the focal position can be used. It is also possible to apply a method (contrast autofocus) of detecting the position where the contrast of the image is highest as the focal position. The image pickup control unit 1003 adjusts the position of the lens 1001 via the lens drive unit 1004 based on the detected focal position, and performs autofocus. The image pickup control unit 1003 can be configured by, for example, a DSP (Digital Signal Processor) equipped with firmware.

The lens driving unit 1004 drives the lens 1001 based on 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.

The image processing unit 1005 processes the image signal generated by the image sensor 1002. This processing includes, for example, demosaic to generate an image signal of a color that is insufficient among the image signals corresponding to red, green, and blue for each pixel, noise reduction to remove noise of the image signal, and coding of the image signal. Applicable. The image processing unit 1005 can be configured by, for example, a microcomputer equipped with firmware.

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

The frame memory 1007 is a memory that stores a frame that is an image signal for one screen. The frame memory 1007 is controlled by the image processing unit 1005 and holds frames in the process of image processing.

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.

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

The cameras to which this disclosure can be applied have been described above. The present technology can be applied to the image pickup device 1002 among the configurations described above. Specifically, the image pickup device 1 described with reference to FIG. 1 can be applied to the image pickup device 1002. By applying the image sensor 1 to the image sensor 1002, the reflected light is reduced, and it is possible to prevent deterioration of the image quality of the image generated by the camera 1000.

Although the camera has been described here as an example, the technology according to the present disclosure may be applied to other devices such as a distance sensor. Further, the present disclosure can be applied to a semiconductor device in the form of a semiconductor module in addition to an electronic device such as a camera. Specifically, the technique according to the present disclosure can be applied to an image pickup module which is a semiconductor module in which the image pickup device 1002 and the image pickup control unit 1003 of FIG. 37 are enclosed in one package.

<Example of application to endoscopic surgery system>
The technology according to the present disclosure (the present technology) can be applied to various products. For example, the techniques according to the present disclosure may be applied to endoscopic surgery systems.

FIG. 38 is a diagram showing an example of a schematic configuration of an endoscopic surgery system to which the technique according to the present disclosure (the present technique) can be applied.

FIG. 38 shows a surgeon (doctor) 11131 performing surgery on patient 11132 on patient bed 11133 using the endoscopic surgery system 11000. As shown, the endoscopic surgery system 11000 includes an endoscope 11100, other surgical tools 11110 such as a pneumoperitoneum tube 11111 and an energy treatment tool 11112, and a support arm device 11120 that supports the endoscope 11100. , A cart 11200 equipped with various devices for endoscopic surgery.

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

An opening in 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 the 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 to be an objective. It is irradiated toward the observation target in the body cavity of the patient 11132 through the lens. The endoscope 11100 may be a direct endoscope, a perspective mirror, or a side endoscope.

An optical system and an image pickup element are provided inside the camera head 11102, and the reflected light (observation light) from the observation target is focused on the image pickup element by the optical system. The observation light is photoelectrically converted by the image pickup device, and an electric signal corresponding to the observation light, that is, an image signal corresponding to the observation image is generated. The image signal is transmitted as RAW data to the camera control unit (CCU: Camera Control Unit) 11201.

The CCU11201 is composed of a CPU (Central Processing Unit), a GPU (Graphics Processing Unit), etc., and comprehensively controls the operations of the endoscope 11100 and the display device 11202. Further, the CCU 11201 receives an image signal from the camera head 11102, and performs various image processing on the image signal for displaying an image based on the image signal, such as development processing (demosaic processing).

The display device 11202 displays an image based on the image signal processed by the CCU 11201 under the control of the CCU 11201.

The light source device 11203 is composed of, for example, a light source such as an LED (light LED radio), and supplies irradiation light to the endoscope 11100 when photographing an operating part or the like.

The input device 11204 is an input interface for the endoscopic surgery system 11000. The user can input various information and input 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 irradiation light, magnification, focal length, etc.) by the endoscope 11100.

The treatment tool control device 11205 controls the drive of the energy treatment tool 11112 for cauterizing, incising, sealing a blood vessel, or the like of a tissue. The pneumoperitoneum device 11206 uses a gas in the pneumoperitoneum tube 11111 to inflate the body cavity of the patient 11132 for the purpose of securing the field of view by the endoscope 11100 and securing the work space of the operator. To send. The recorder 11207 is a device capable of recording various information related to surgery. The printer 11208 is a device capable of printing various information related to surgery in various formats such as text, images, and graphs.

The light source device 11203 that supplies the irradiation light to the endoscope 11100 when photographing the surgical site can be composed of, for example, an LED, a laser light source, or a white light source composed of a combination thereof. When a white light source is configured by combining RGB laser light sources, the output intensity and output timing of each color (each wavelength) can be controlled with high accuracy. Therefore, the light source device 11203 adjusts the white balance of the captured image. It can be carried out. Further, in this case, the laser light from each of the RGB laser light sources is irradiated to the observation target in a time-divided manner, and the drive of the image sensor of the camera head 11102 is controlled in synchronization with the irradiation timing to support each of RGB. It is also possible to capture the image in a time-divided manner. According to this method, a color image can be obtained without providing a color filter on the image sensor.

Further, the drive of the light source device 11203 may be controlled so as to change the intensity of the output light at predetermined time intervals. By controlling the drive of the image sensor of the camera head 11102 in synchronization with the timing of changing the light intensity to acquire an image in a time-divided manner and synthesizing the image, so-called high dynamic without blackout and overexposure. Range images can be generated.

Further, the light source device 11203 may be configured to be able to supply light in a predetermined wavelength band corresponding to special light observation. In special light observation, for example, by utilizing the wavelength dependence of light absorption in body tissue to irradiate light in a narrower band than the irradiation light (that is, white light) during normal observation, the surface layer of the mucous membrane So-called narrow band imaging, in which a predetermined tissue such as a blood vessel is photographed with high contrast, is performed. Alternatively, in the special light observation, fluorescence observation may be performed in which an image is obtained by fluorescence generated by irradiating with excitation light. In fluorescence observation, the body tissue is irradiated with excitation light to observe the fluorescence from the body tissue (autofluorescence observation), or a reagent such as indocyanine green (ICG) is locally injected into the body tissue and the body tissue is injected. It is possible to obtain a fluorescence image by irradiating excitation light corresponding to the fluorescence wavelength of the reagent. The light source device 11203 may be configured to be capable of supplying narrow band light and / or excitation light corresponding to such special light observation.

FIG. 39 is a block diagram showing an example of the functional configuration of the camera head 11102 and CCU11201 shown in FIG. 38.

The camera head 11102 includes a lens unit 11401, an imaging unit 11402, a driving unit 11403, a communication unit 11404, and a camera head control unit 11405. CCU11201 includes a communication unit 11411, an image processing unit 11412, and a control unit 11413. The camera head 11102 and CCU11201 are communicatively connected to each other by a transmission cable 11400.

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

The image sensor constituting the image pickup unit 11402 may be one (so-called single plate type) or a plurality (so-called multi-plate type). When the image pickup unit 11402 is composed of a multi-plate type, for example, each image pickup element may generate an image signal corresponding to each of RGB, and a color image may be obtained by synthesizing them. Alternatively, the image pickup unit 11402 may be configured to have a pair of image pickup elements for acquiring image signals for the right eye and the left eye corresponding to 3D (dimensional) display, respectively. The 3D display enables the operator 11131 to more accurately grasp the depth of the biological tissue in the surgical site.
When the image pickup unit 11402 is composed of a multi-plate type, a plurality of lens units 11401 may be provided corresponding to each image pickup element.

Further, the imaging unit 11402 does not necessarily have to be provided on the camera head 11102. For example, the imaging unit 11402 may be provided inside the lens barrel 11101 immediately after the objective lens.

The drive unit 11403 is composed of an actuator, and the zoom lens and focus lens of the lens unit 11401 are moved by a predetermined distance along the optical axis under the control of the camera head control unit 11405. As a result, the magnification and focus of the image captured by the imaging unit 11402 can be adjusted as appropriate.

The communication unit 11404 is composed of a communication device for transmitting and receiving various information to and from the CCU11201. The communication unit 11404 transmits the image signal obtained from the image pickup unit 11402 as RAW data to the CCU 11201 via the transmission cable 11400.

Further, the communication unit 11404 receives a control signal for controlling the drive 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, for example, information to specify the frame rate of the captured image, information to specify the exposure value at the time of imaging, and / or information to specify the magnification and focus of the captured image, and the like. Contains information about the condition.

The above-mentioned imaging conditions such as frame rate, exposure value, magnification, and focus may be appropriately specified by the user, or may be automatically set by the control unit 11413 of CCU11201 based on the acquired image signal. Good. In the latter case, the so-called AE (Auto Exposure) function, AF (Auto Focus) function, and AWB (Auto White Balance) function are mounted on the endoscope 11100.

The camera head control unit 11405 controls the drive of the camera head 11102 based on the control signal from the CCU 11201 received via the communication unit 11404.

The communication unit 11411 is composed of 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.

Further, the communication unit 11411 transmits a control signal for controlling the drive of the camera head 11102 to the camera head 11102. Image signals and control signals can be transmitted by telecommunications, optical communication, or the like.

The image processing unit 11412 performs various image processing on the image signal which is the RAW data transmitted from the camera head 11102.

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

Further, the control unit 11413 causes the display device 11202 to display an image captured by the surgical unit or the like based on the image signal processed by the image processing unit 11412. At this time, the control unit 11413 may recognize various objects in the captured image by using various image recognition techniques. For example, the control unit 11413 detects the shape, color, and the like of the edge of an object included in the captured image to remove surgical tools such as forceps, a specific biological part, bleeding, and mist when using the energy treatment tool 11112. Can be recognized. When displaying the captured image on the display device 11202, the control unit 11413 may superimpose and display various surgical support information on the image of the surgical unit by using the recognition result. By superimposing and displaying the surgical support information and presenting it to the surgeon 11131, it is possible to reduce the burden on the surgeon 11131 and to allow the surgeon 11131 to proceed with the surgery reliably.

The transmission cable 11400 that connects the camera head 11102 and CCU11201 is an electric signal cable that supports electric signal communication, an optical fiber that supports optical communication, or a composite cable thereof.

Here, in the illustrated example, the communication is performed by wire using the transmission cable 11400, but the communication between the camera head 11102 and the CCU11201 may be performed wirelessly.

<Example of application to mobiles>
The technology according to the present disclosure (the present technology) can be applied to various products. For example, the technology according to the present disclosure is realized as a device mounted on a moving body of any kind such as an automobile, an electric vehicle, a hybrid electric vehicle, a motorcycle, a bicycle, a personal mobility, an airplane, a drone, a ship, and a robot. You may.

FIG. 40 is a block diagram showing a schematic configuration example of a vehicle control system, which is an example of a mobile control system to which the technology according to the present disclosure can be applied.

The vehicle control system 12000 includes a plurality of electronic control units connected via the communication network 12001. In the example shown in FIG. 40, the vehicle control system 12000 includes a drive system control unit 12010, a body system control unit 12020, an outside information detection unit 12030, an in-vehicle information detection unit 12040, and an integrated control unit 12050. Further, as a functional configuration of the integrated control unit 12050, a microcomputer 12051, an audio image output unit 12052, and an in-vehicle network I / F (Interface) 12053 are shown.

The drive system control unit 12010 controls the operation of the device related to the drive system of the vehicle according to various programs. For example, the drive system control unit 12010 provides a driving force generator for generating the driving force of the vehicle such as an internal combustion engine or a driving motor, a driving force transmission mechanism for transmitting the driving force to the wheels, and a steering angle of the vehicle. It functions as a control device such as a steering mechanism for adjusting and a braking device for generating a braking force of a vehicle.

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 keyless entry system, a smart key system, a power window device, or a control device for various lamps such as headlamps, back lamps, brake lamps, blinkers or fog lamps. In this case, the body system control unit 12020 may be input with radio waves transmitted from a portable device that substitutes for the key or signals of various switches. The body system control unit 12020 receives inputs of these radio waves or signals and controls a vehicle door lock device, a power window device, a lamp, and the like.

The vehicle outside information detection unit 12030 detects information outside the vehicle equipped with the vehicle control system 12000. For example, the image pickup unit 12031 is connected to the vehicle exterior information detection unit 12030. The vehicle outside information detection unit 12030 causes the image pickup unit 12031 to capture an image of the outside of the vehicle and receives the captured image. The vehicle exterior information detection unit 12030 may perform object detection processing or distance detection processing such as a person, a vehicle, an obstacle, a sign, or a character on the road surface based on the received image.

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

The in-vehicle information detection unit 12040 detects the in-vehicle information. For example, a driver state detection unit 12041 that detects the driver's state is connected to the in-vehicle information detection unit 12040. The driver state detection unit 12041 includes, for example, a camera that images the driver, and the in-vehicle information detection unit 12040 determines the degree of fatigue or concentration of the driver based on the detection information input from the driver state detection unit 12041. It may be calculated, or it may be determined whether the driver is dozing.

The microcomputer 12051 calculates the control target value of the driving force generator, the steering mechanism, or the braking device based on the information inside and outside the vehicle acquired by the vehicle exterior information detection unit 12030 or the vehicle interior information detection unit 12040, and the drive system control unit. A control command can be output to 12010. For example, the microcomputer 12051 realizes ADAS (Advanced Driver Assistance System) functions including vehicle collision avoidance or impact mitigation, follow-up driving based on inter-vehicle distance, vehicle speed maintenance driving, vehicle collision warning, vehicle lane deviation warning, and the like. It is possible to perform cooperative control for the purpose of.

Further, the microcomputer 12051 controls the driving force generator, the steering mechanism, the braking device, and the like based on the information around the vehicle acquired by the vehicle exterior information detection unit 12030 or the vehicle interior information detection unit 12040, so that the driver can control the driver. It is possible to perform coordinated control for the purpose of automatic driving, etc., which runs autonomously without depending on the operation.

Further, the microcomputer 12051 can output a control command to the body system control unit 12030 based on the information outside the vehicle acquired by the vehicle exterior information detection unit 12030. For example, the microcomputer 12051 controls the headlamps according to the position of the preceding vehicle or the oncoming vehicle detected by the external information detection unit 12030, and performs cooperative control for the purpose of antiglare such as switching the high beam to the low beam. It can be carried out.

The audio image output unit 12052 transmits an output signal of at least one of audio and an image to an output device capable of visually or audibly notifying information to the passenger or the outside of the vehicle. In the example of FIG. 40, an audio speaker 12061, a display unit 12062, and an instrument panel 12063 are exemplified as output devices. The display unit 12062 may include, for example, at least one of an onboard display and a heads-up display.

FIG. 41 is a diagram showing an example of the installation position of the imaging unit 12031.

In FIG. 41, the imaging unit 12031 includes

imaging units

12101, 12102, 12103, 12104, and 12105.

The

imaging units

12101, 12102, 12103, 12104, 12105 are provided at positions such as, for example, the front nose, side mirrors, rear bumpers, back doors, and the upper part of the windshield in the vehicle interior of the vehicle 12100. The imaging unit 12101 provided on the front nose and the imaging unit 12105 provided on the upper part of the windshield in the vehicle interior mainly acquire an image in front of the vehicle 12100. The

imaging units

12102 and 12103 provided in the side mirrors mainly acquire images of the side of the vehicle 12100. The imaging unit 12104 provided on the rear bumper or the back door mainly acquires an image of the rear of the vehicle 12100. The imaging unit 12105 provided on the upper part of the windshield in the vehicle interior is mainly used for detecting a preceding vehicle, a pedestrian, an obstacle, a traffic light, a traffic sign, a lane, or the like.

Note that FIG. 41 shows an example of the photographing range of the imaging units 12101 to 12104. The imaging range 12111 indicates the imaging range of the imaging unit 12101 provided on the front nose, the imaging ranges 12112 and 12113 indicate the imaging ranges of the

imaging units

12102 and 12103 provided on the side mirrors, respectively, and the imaging range 12114 indicates the imaging range of the

imaging units

12102 and 12103. The imaging range of the imaging unit 12104 provided on the rear bumper or the back door is shown. For example, by superimposing the image data captured by the imaging units 12101 to 12104, a bird's-eye view image of the vehicle 12100 as viewed from above can be obtained.

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 image pickup units 12101 to 12104 may be a stereo camera composed of a plurality of image pickup elements, or may be an image pickup element having pixels for phase difference detection.

For example, the microcomputer 12051 has a distance to each three-dimensional object within the imaging range 12111 to 12114 based on the distance information obtained from the imaging units 12101 to 12104, and a temporal change of this distance (relative velocity with respect to the vehicle 12100). By obtaining, it is possible to extract as the preceding vehicle a three-dimensional object that is the closest three-dimensional object on the traveling path of the vehicle 12100 and that travels in substantially the same direction as the vehicle 12100 at a predetermined speed (for example, 0 km / h or more). it can. Further, the microcomputer 12051 can set an inter-vehicle distance to be secured in front of the preceding vehicle in advance, and can perform automatic braking control (including follow-up stop control), automatic acceleration control (including follow-up start control), and the like. In this way, it is possible to perform coordinated control for the purpose of automatic driving or the like in which the vehicle runs autonomously without depending on the operation of the driver.

For example, the microcomputer 12051 converts three-dimensional object data related to a three-dimensional object into two-wheeled vehicles, ordinary vehicles, large vehicles, pedestrians, electric poles, and other three-dimensional objects based on the distance information obtained from the imaging units 12101 to 12104. It can be classified and extracted and used for automatic avoidance of obstacles. For example, the microcomputer 12051 distinguishes obstacles around the vehicle 12100 into obstacles that can be seen by the driver of the vehicle 12100 and obstacles that are difficult to see. Then, the microcomputer 12051 determines the collision risk indicating the risk of collision with each obstacle, and when the collision risk is equal to or higher than the set value and there is a possibility of collision, the microcomputer 12051 via the audio speaker 12061 or the display unit 12062. By outputting an alarm to the driver and performing forced deceleration and avoidance steering via the drive system control unit 12010, driving support for collision avoidance can be provided.

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 image of the imaging units 12101 to 12104. Such pedestrian recognition includes, for example, a procedure for extracting feature points in an image captured by an imaging unit 12101 to 12104 as an infrared camera, and pattern matching processing for a series of feature points indicating the outline of an object to determine whether or not the pedestrian is a pedestrian. It is done by the procedure to determine. 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 outputs a square contour line for emphasizing the recognized pedestrian. The display unit 12062 is controlled so as to superimpose and display. Further, the audio image output unit 12052 may control the display unit 12062 so as to display an icon or the like indicating a pedestrian at a desired position.

In the present specification, the system represents the entire device composed of a plurality of devices.

Note that the effects described in this specification are merely examples and are not limited, and other effects may be obtained.

The embodiment of the present technology is not limited to the above-described embodiment, and various changes can be made without departing from the gist of the present technology.

The present technology can also have the following configurations.
(1)
An on-chip lens that collects incident light and
A photoelectric conversion unit that performs photoelectric conversion of the incident light and
An opening having a size substantially the same as the focused size of the incident light, a waveguide for guiding the incident light to the photoelectric conversion unit, and a waveguide.
A reflective film that reflects the incident light that has passed through the photoelectric conversion unit, and
An image pickup device including a concavo-convex region having a plurality of concavities and convexities on the side of the photoelectric conversion unit on which the incident light is incident.
(2)
The image pickup device according to (1) above, wherein the reflective film has an inclined surface.
(3)
When the inclination angle of the inclined surface is θ, the size of the opening is D, and the depth of the photoelectric conversion unit is T,
θ ≧ (1/2) arctan (D / 2T)
The image pickup device according to (2) above.
(4)
The image pickup device according to any one of (1) to (3), further comprising a second uneven region having a plurality of irregularities on the side of the photoelectric conversion unit facing the incident side.
(5)
The image pickup device according to any one of (1) to (4) above, wherein the waveguide has an inclination.
(6)
The image pickup device according to any one of (1) to (5) above, further comprising a reflecting unit that reflects light in the photoelectric conversion unit.
(7)
The image pickup device according to (6) above, wherein a plurality of the reflecting portions are provided.
(8)
The image pickup device according to any one of (1) to (7) above, wherein a recess is formed on the opening side of the photoelectric conversion unit, and the refractive index of the material inside the recess is different from that of the material outside. ..
(9)
The inclined surface of the reflective film is high on the side provided with the charge accumulating portion for accumulating the charges converted by the photoelectric conversion unit and low on the side not provided with the charge accumulating portion (2) to (8). ). The image pickup device.
(10)
The image pickup device according to any one of (1) to (9) above, further comprising a reflection unit that reflects light in the vicinity of the charge storage unit that stores the charge converted by the photoelectric conversion unit.
(11)
The image pickup device according to (1), wherein the reflective film is provided between a charge storage unit that stores charges converted by the photoelectric conversion unit and the photoelectric conversion unit.
(12)
The image pickup device according to any one of (1) to (11) above, wherein the waveguide is a diffraction grating.
(13)
An on-chip lens that collects incident light and
A photoelectric conversion unit that performs photoelectric conversion of the incident light and
An opening having a size substantially the same as the focused size of the incident light, a waveguide for guiding the incident light to the photoelectric conversion unit, and a waveguide.
A reflective film that reflects the incident light that has passed through the photoelectric conversion unit, and
An image pickup apparatus including an image pickup element having a plurality of unevenness regions on the side of the photoelectric conversion unit on which the incident light is incident, and a processing unit for processing a signal from the image pickup element.
(14)
An on-chip lens that collects incident light and
A photoelectric conversion unit that performs photoelectric conversion of the incident light and
An opening having a size substantially the same as the focused size of the incident light,
A reflective film that reflects the incident light that has passed through the photoelectric conversion unit and has an inclined surface.
An image pickup device including a concavo-convex region having a plurality of concavities and convexities on the side of the photoelectric conversion unit on which the incident light is incident.
(15)
The image pickup device according to (14), further comprising a second uneven region having a plurality of irregularities on the side of the photoelectric conversion unit facing the incident side.
(16)
The image pickup device according to (14) or (15), further comprising a reflecting unit that reflects light in the photoelectric conversion unit.
(17)
The image pickup device according to (16), wherein a plurality of the reflecting portions are provided.
(18)
The image pickup device according to any one of (14) to (16), wherein a recess is formed on the opening side of the photoelectric conversion unit, and the refractive index of the material inside the recess is different from that of the material outside. ..
(19)
An on-chip lens that collects incident light and
A photoelectric conversion unit that performs photoelectric conversion of the incident light and
An opening having a size substantially the same as the focused size of the incident light,
A reflective film that reflects the incident light that has passed through the photoelectric conversion unit and has an inclined surface.
An image pickup apparatus including an image pickup element having a plurality of unevenness regions on the side of the photoelectric conversion unit on which the incident light is incident, and a processing unit for processing a signal from the image pickup element.

1 image pickup element, 10 pixel array unit, 11 vertical drive unit, 12 column signal processing unit, 13 control unit, 14, 15, 16 signal lines, 30 pixels, 31 semiconductor substrate, 32 semiconductor area, 33 wiring area, 34 surface side Reflective film, 35 backside reflective film, 36 protective film, 37 on-chip lens, 38 separation area, 41 insulating layer, 42 wiring layer, 51 substrate backside scattering part, 52 opening, 71, 72 incident light, 91 absorbing film, 101 front side reflective film, 109 substrate back surface scattering part, 111, 112, 113, 114, 115 reflection part, 131 substrate surface scattering part, 151 substrate back surface scattering part, 152 light refraction structure part, 201 waveguide, 221 color filter layer , 301 waveguide, 311, 312, 313 reflector, 321 substrate back surface scatterer, 322 substrate surface scatterer, 351, 361 reflector

Claims

An on-chip lens that collects incident light and
A photoelectric conversion unit that performs photoelectric conversion of the incident light and
An opening having a size substantially the same as the focused size of the incident light, a waveguide for guiding the incident light to the photoelectric conversion unit, and a waveguide.
A reflective film that reflects the incident light that has passed through the photoelectric conversion unit, and
An image pickup device including a concavo-convex region having a plurality of concavities and convexities on the side of the photoelectric conversion unit on which the incident light is incident.
The image pickup device according to claim 1, wherein the reflective film has an inclined surface.
When the inclination angle of the inclined surface is θ, the size of the opening is D, and the depth of the photoelectric conversion unit is T,
θ ≧ (1/2) arctan (D / 2T)
2. The image pickup device according to claim 2.
The image pickup device according to claim 1, further comprising a second uneven region having a plurality of irregularities on the side of the photoelectric conversion unit facing the incident side.
The image pickup device according to claim 1, wherein the waveguide has an inclination.
The image pickup device according to claim 1, further comprising a reflecting unit that reflects light in the photoelectric conversion unit.
The image pickup device according to claim 6, wherein a plurality of the reflecting portions are provided.
The image pickup device according to claim 1, wherein a recess is formed on the opening side of the photoelectric conversion unit, and the refractive index of the material inside the recess is different from that of the material outside.
The image pickup according to claim 2, wherein the inclined surface of the reflective film is high on the side provided with the charge accumulating portion for accumulating the charges converted by the photoelectric conversion unit and low on the side not provided with the charge accumulating portion. element.
The image pickup device according to claim 1, further comprising a reflection unit that reflects light in the vicinity of the charge storage unit that stores the charges converted by the photoelectric conversion unit.
The image pickup device according to claim 1, wherein the reflective film is provided between a charge storage unit that stores charges converted by the photoelectric conversion unit and the photoelectric conversion unit.
The image pickup device according to claim 1, wherein the waveguide is a diffraction grating.
An on-chip lens that collects incident light and
A photoelectric conversion unit that performs photoelectric conversion of the incident light and
An opening having a size substantially the same as the focused size of the incident light, a waveguide for guiding the incident light to the photoelectric conversion unit, and a waveguide.
A reflective film that reflects the incident light that has passed through the photoelectric conversion unit, and
An image pickup apparatus including an image pickup element having a plurality of unevenness regions on the side of the photoelectric conversion unit on which the incident light is incident, and a processing unit for processing a signal from the image pickup element.
An on-chip lens that collects incident light and
A photoelectric conversion unit that performs photoelectric conversion of the incident light and
An opening having a size substantially the same as the focused size of the incident light,
A reflective film that reflects the incident light that has passed through the photoelectric conversion unit and has an inclined surface.
An image pickup device including a concavo-convex region having a plurality of concavities and convexities on the side of the photoelectric conversion unit on which the incident light is incident.
The image pickup device according to claim 14, further comprising a second uneven region having a plurality of irregularities on the side of the photoelectric conversion unit facing the incident side.
The image pickup device according to claim 14, further comprising a reflecting unit that reflects light in the photoelectric conversion unit.
The image pickup device according to claim 16, wherein a plurality of the reflecting portions are provided.
The image pickup device according to claim 14, wherein a recess is formed on the opening side of the photoelectric conversion unit, and the refractive index of the material inside the recess is different from that of the material outside.
An on-chip lens that collects incident light and
A photoelectric conversion unit that performs photoelectric conversion of the incident light and
An opening having a size substantially the same as the focused size of the incident light,
A reflective film that reflects the incident light that has passed through the photoelectric conversion unit and has an inclined surface.
An image pickup apparatus including an image pickup element having a plurality of unevenness regions on the side of the photoelectric conversion unit on which the incident light is incident, and a processing unit for processing a signal from the image pickup element.