JP2021174930A - Imaging device and imaging system - Google Patents

Abstract

To provide an imaging device in which noise is suppressed.SOLUTION: An imaging device 100 includes: a semiconductor substrate 110; a charge accumulation electrode 190, an insulating layer 120, a semiconductor layer 130, a photoelectric conversion layer 140, and a counter electrode 150 that exist over the semiconductor substrate 110 and are stacked in this order; a pixel electrode 160 being disposed apart from the photoelectric conversion layer 140 and electrically connected to the photoelectric conversion layer 140 through the semiconductor layer 130; and a blocking layer 170 existing between the photoelectric conversion layer 140 and the pixel electrode 160, overlapping with at least a part of the pixel electrode 160 in a plan view, and blocking a signal charge generated in the photoelectric conversion layer 140. At least a part of the charge accumulation electrode 190 does not overlap with the blocking layer 170 in a plan view.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to an imaging apparatus and an imaging system.

An imaging device using photoelectric conversion such as a CCD (Charge Coupled Device) image sensor and a CMOS (Complementary Metal Oxide Sensor) image sensor is known (see, for example, Patent Document 1).

International Publication No. 2019/181456

The present disclosure provides an image pickup apparatus and an image pickup system in which noise is suppressed.

The image pickup apparatus according to one aspect of the present disclosure includes a semiconductor substrate, a first electrode, an insulating layer, a semiconductor layer, a photoelectric conversion layer and a second electrode, which are located above the semiconductor substrate and are laminated in this order, and the photoelectric. The third electrode, which is arranged apart from the conversion layer and is electrically connected to the photoelectric conversion layer via the semiconductor layer, is located between the photoelectric conversion layer and the third electrode, and is located in a plan view. A blocking layer that overlaps with at least a part of the third electrode and blocks the signal charge generated in the photoelectric conversion layer is provided, and at least a part of the first electrode overlaps with the blocking layer in a plan view. It doesn't become.

The imaging system according to one aspect of the present disclosure includes the imaging device, an optical system that concentrates light on the imaging device, and a processing circuit that processes a signal output by the imaging device.

According to the present disclosure, an image pickup apparatus and an image pickup system in which noise is suppressed are provided.

FIG. 1 is a cross-sectional view of the image pickup apparatus according to the first embodiment. FIG. 2 is a cross-sectional view showing one step of the manufacturing method of the image pickup apparatus according to the first embodiment. FIG. 3 is a cross-sectional view showing the steps following FIG. FIG. 4 is a cross-sectional view showing the steps following FIG. FIG. 5 is a cross-sectional view showing the steps following FIG. FIG. 6 is a cross-sectional view showing the steps following FIG. FIG. 7 is a cross-sectional view showing the steps following FIG. FIG. 8 is a cross-sectional view of the image pickup apparatus according to the second embodiment. FIG. 9 is a cross-sectional view of the image pickup apparatus according to the third embodiment. FIG. 10 is a cross-sectional view of the image pickup apparatus according to the fourth embodiment. FIG. 11 is a cross-sectional view of the image pickup apparatus according to the first modification of the fourth embodiment. FIG. 12 is a cross-sectional view of the image pickup apparatus according to the second modification of the fourth embodiment. FIG. 13 is a cross-sectional view of the image pickup apparatus according to the fifth embodiment. FIG. 14 is a cross-sectional view of the image pickup apparatus according to the sixth embodiment. FIG. 15 is a diagram schematically showing a configuration example of the imaging system according to the seventh embodiment.

(Findings underlying this disclosure)
The present inventors have found that the following problems arise with respect to the conventional imaging device.

In the image pickup apparatus disclosed in Patent Document 1, a light-shielding film is provided so as to cover the photoelectric conversion layer at a portion facing the readout electrode. As a result, the photoelectric conversion in the region close to the read electrode is suppressed, and the transfer of excess signal charge to the read electrode is suppressed.

However, light is incident on the photoelectric conversion layer on the readout electrode even from an oblique direction. The signal charge generated by such incident light can be mixed in the readout electrode and become noise. The present inventors have diligently studied this subject and came up with the present disclosure.

The image pickup apparatus according to one aspect of the present disclosure includes a semiconductor substrate, a first electrode, an insulating layer, a semiconductor layer, a photoelectric conversion layer and a second electrode, which are located above the semiconductor substrate and are laminated in this order, and the photoelectric. The third electrode, which is arranged apart from the conversion layer and is electrically connected to the photoelectric conversion layer via the semiconductor layer, is located between the photoelectric conversion layer and the third electrode, and is located in a plan view. A blocking layer that overlaps with at least a part of the third electrode and blocks the signal charge generated in the photoelectric conversion layer is provided. At least a part of the first electrode does not overlap with the blocking layer in a plan view.

As a result, the signal charge generated in the region overlapping the third electrode in the plan view in the photoelectric conversion layer can be blocked by the blocking layer. Therefore, even if light from an oblique direction is incident, it is possible to suppress the mixing of signal charges into the third electrode. As described above, according to the image pickup apparatus according to this aspect, it is possible to suppress noise caused by the mixing of electric charges.

Further, for example, the blocking layer may be located between the semiconductor layer and the third electrode.

As a result, it is possible to suppress the signal charge from being mixed into the third electrode by the blocking layer, so that noise caused by the charge mixing can be suppressed.

Further, for example, the blocking layer may be located between the photoelectric conversion layer and the semiconductor layer.

As a result, it is possible to suppress the signal charge from being mixed into the third electrode by the blocking layer, so that noise caused by the charge mixing can be suppressed.

Further, for example, the blocking layer may be in contact with the photoelectric conversion layer and the third electrode.

As a result, it is possible to suppress the signal charge from being mixed into the third electrode by the blocking layer, so that noise caused by the charge mixing can be suppressed.

Further, for example, the blocking layer may have a larger area than the third electrode in a plan view and may overlap with the entire third electrode.

As a result, the distance between the end of the blocking layer and the third electrode is increased, so that the signal charge that wraps around the blocking layer and is mixed in the third electrode can be suppressed. Therefore, noise caused by the mixing of electric charges can be further suppressed.

Further, for example, the third electrode does not have to overlap with the first electrode in a plan view.

As a result, the first electrode for accumulating the signal charge and the third electrode for collecting the signal charge can be separated from each other, so that the signal charge mixed in the third electrode can be suppressed.

Further, for example, the second electrode may face the third electrode via the blocking layer and the photoelectric conversion layer.

This eliminates the need for patterning of the second electrode, so that the film quality of the second electrode can be improved. For example, since the resistance component of the second electrode can be reduced, the voltage drop in the second electrode can be suppressed, and it becomes easy to realize a uniform potential distribution in the plane of the second electrode. As a result, it is possible to suppress variations in the generated charges and generate a good image.

Further, for example, the blocking layer may have an insulating property.

As a result, both electrons and holes can be blocked, so that noise can be further suppressed.

Further, for example, the blocking layer may have a light-shielding property.

As a result, it is possible to suppress the light from being reflected by the third electrode and propagating to the adjacent pixels, so that it is possible to suppress color mixing between the pixels.

Further, for example, a fourth electrode facing the second electrode may be further provided via the insulating layer, the semiconductor layer, and the photoelectric conversion layer. The fourth electrode may be located between the first electrode and the third electrode in a plan view.

Thereby, the transfer of the signal charge to the third electrode can be controlled by the potential applied to the fourth electrode. Therefore, according to the image pickup apparatus according to this aspect, not only can noise due to the mixing of electric charges be suppressed, but also transfer efficiency can be improved.

Further, for example, the first electrode does not have to overlap the blocking layer as a whole in a plan view.

As a result, the signal charge generated in the region located between the first electrode and the second electrode in the photoelectric conversion layer can be transferred to the semiconductor layer without being blocked by the blocking layer. As a result, the signal charge generated in the photoelectric conversion layer can be effectively used.

Further, for example, the semiconductor substrate may include a photoelectric conversion unit that overlaps with the first electrode in a plan view.

As a result, not only can noise due to the mixing of electric charges be suppressed, but also, for example, when the photoelectric conversion layer and the photoelectric conversion unit have sensitivity to different wavelength components, each signal of a plurality of wavelength components can be extracted. .. Thereby, the color resolution of the image pickup apparatus can be improved.

Further, for example, the semiconductor substrate may include a diffusion region, and the third electrode may be electrically connected to the diffusion region.

As a result, the signal charge generated in the photoelectric conversion layer can be temporarily accumulated.

Further, for example, the semiconductor substrate may further include a through electrode penetrating from one surface to the other surface, and the third electrode may be electrically connected to the diffusion region via the through electrode.

Thereby, for example, a back-illuminated image pickup apparatus can be realized.

Further, the imaging system according to the present disclosure includes an imaging device according to each of the above aspects, an optical system that collects light on the imaging device, and a processing circuit that processes a signal output by the imaging device.

As a result, noise caused by the mixing of electric charges can be suppressed and a good image can be generated, as in the case of the image pickup apparatus.

Hereinafter, the image pickup apparatus and the image pickup system according to the embodiment will be specifically described with reference to the drawings.

In the following description, an unnecessarily detailed description may be omitted. For example, detailed explanations of already well-known matters and duplicate explanations for substantially the same configuration may be omitted. This is to avoid unnecessary redundancy of the following description and to facilitate the understanding of those skilled in the art.

In addition, all of the embodiments described below show comprehensive or specific examples. Numerical values, shapes, materials, components, arrangement positions and connection forms of components, steps, step order, and the like shown in the following embodiments are examples, and are not intended to limit the present disclosure. Further, among the components in the following embodiments, the components not described in the independent claims will be described as arbitrary components.

Further, each figure is a schematic view and is not necessarily exactly illustrated. Therefore, for example, the scales and the like do not always match in each figure. Further, in each figure, substantially the same configuration is designated by the same reference numerals, and duplicate description will be omitted or simplified.

Further, in the present specification, the term indicating the shape of an element and the numerical range mean not only an expression expressing only a strict meaning but also a substantially equivalent range, for example, a difference of about several percent. It is an expression.

Further, in the present specification, "planar view" means to see the main surface of the semiconductor substrate from the normal direction unless otherwise specified. Further, the normal direction of the main surface of the semiconductor substrate may be described as "thickness direction" or "lamination direction".

Further, in the present specification, the terms "upper" and "lower" do not refer to the upward direction (vertically upward) and the downward direction (vertically downward) in absolute spatial recognition, but are based on the stacking order in the stacking configuration. It is used as a term defined by the relative positional relationship with. Also, the terms "upper" and "lower" are used not only when the two components are spaced apart from each other and another component exists between the two components, but also when the two components It also applies when the two components are placed in close contact with each other and touch each other.

Also, the various aspects described herein can be combined with each other as long as there is no conflict.

In the present specification, the ordinal numbers such as first, second, third ... May be used. If an element has an ordinal number, it is not essential that a younger element of the same type exists. The ordinal numbers can be changed as needed.

(Embodiment 1)
[composition]
First, the configuration of the image pickup apparatus according to the first embodiment will be described with reference to FIG. FIG. 1 is a cross-sectional view of the image pickup apparatus 100 according to the present embodiment.

As shown in FIG. 1, the image pickup apparatus 100 includes a semiconductor substrate 110, an insulating layer 120, a semiconductor layer 130, a photoelectric conversion layer 140, a counter electrode 150, a sealing film 151, and a pixel electrode 160. It includes a plug 161, a blocking layer 170, a diffusion region 180, a wiring layer 181 and a charge storage electrode 190.

The semiconductor substrate 110 includes a diffusion region 180 and a charge detection circuit (not shown). A wiring layer 181, an insulating layer 120, a semiconductor layer 130, a photoelectric conversion layer 140, a counter electrode 150, and a sealing film 151 are laminated in this order above the semiconductor substrate 110. The semiconductor substrate 110 contains, for example, silicon.

The diffusion region 180 is an impurity region formed near the surface of the semiconductor substrate 110. The diffusion region 180 is formed by adding a conductive type impurity different from the conductive type of the semiconductor constituting the semiconductor substrate 110 near the surface of the semiconductor substrate 110. For example, when the semiconductor substrate 110 is a p-type Si substrate, the diffusion region 180 is formed by adding n-type impurities. The diffusion region 180 is electrically connected to various transistors such as a readout transistor included in the charge detection circuit, for example.

The charge detection circuit (not shown) is formed by, for example, combining a plurality of CMOS transistors. The charge detection circuit includes, for example, an amplification transistor that outputs a signal corresponding to the signal charge transferred to the diffusion region 180, and a reset transistor that resets the diffusion region 180.

The insulating layer 120 is a layer that electrically separates the charge storage electrode 190 and the semiconductor layer 130, and is provided on the wiring layer 181. The insulating layer 120 is a single-layer film containing, for example, one of tetraethyl orthosilicate (TEOS), silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, hafnium silicate, zirconium silicate, hafnium oxide, and zirconia. , Or, it is composed of a laminated film containing two or more of these. The insulating layer 120 may have a light-shielding property and may be capable of transmitting light.

The wiring layer 181 includes one or more interlayer insulating layers, and a conductive wiring and via conductor. Wiring and via conductors are formed using a metal such as copper or a conductive material such as polysilicon. The interlayer insulating layer is formed by using an insulating material selected from the materials that can be used for the insulating layer 120.

The semiconductor layer 130 is located above the semiconductor substrate 110. The semiconductor layer 130 is provided in contact with the upper surface of the insulating layer 120. In the present embodiment, the semiconductor layer 130 covers the upper surface of the insulating layer 120, the side surface of the pixel electrode 160, and the upper surface and the side surface of the blocking layer 170. As a result, neither the blocking layer 170 nor the pixel electrode 160 comes into contact with the photoelectric conversion layer 140.

The semiconductor layer 130 functions as a region in which the signal charge generated by the photoelectric conversion layer 140 is accumulated and a path through which the signal charge is transferred. Specifically, the semiconductor layer 130 electrically connects the photoelectric conversion layer 140 and the pixel electrode 160. Electrical connection means that it is electrically conductive at all times or at least at a predetermined timing. In the present embodiment, by controlling the potential difference between the charge storage electrode 190 and the pixel electrode 160, the signal charge stored in the semiconductor layer 130 in the direction directly above the charge storage electrode 190 is transferred to the pixel electrode 160.

The semiconductor layer 130 includes, for example, a material having a higher signal charge mobility than the photoelectric conversion layer 140. The semiconductor layer 130 includes, for example, an oxide semiconductor material such as InGaZnO or InWZnO, a layered material such as silicon carbide, graphene, phosphorene, germanene, pranben, stanene or a transition metal dichalcogenide, or a semiconductor-type carbon nanotube. The semiconductor layer 130 may be a single film or may have a plurality of laminated films.

The photoelectric conversion layer 140 converts light incident from above into hole-electron pairs in an amount corresponding to the amount of light. By providing a potential difference between the counter electrode 150 and the charge storage electrode 190 which is a part of the wiring layer 181, either holes or electrons are used as signal charges in the insulating layer 120 above the charge storage electrode 190 and the semiconductor. It can be accumulated at the boundary portion with the layer 130.

The photoelectric conversion layer 140 includes an organic material or an inorganic material such as carbon nanotubes, quantum dots, or amorphous silicon. The photoelectric conversion layer 140 may include a layer containing an organic material and a layer containing an inorganic material. The layer containing an organic material may include, for example, a structure in which a layer containing a p-type organic semiconductor and a layer containing an n-type organic semiconductor are laminated. Alternatively, the layer containing the organic material may include a structure in which a p-type organic semiconductor and an n-type organic semiconductor are mixed.

As the p-type organic semiconductor, an organic compound having an electron donating property can be used. Examples of the electron-donating organic compound include polyacene derivatives, thiophene derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, perylene derivatives, carbazole derivatives, aniline derivatives and triallylamine derivatives. As the n-type organic semiconductor, a compound having electron acceptability can be used. Examples of the electron-accepting compound include a 5- to 7-membered heterocyclic compound containing a nitrogen atom, an oxygen atom or a sulfur atom, a condensed aromatic carbocyclic compound, a polyarylene compound, a fullerene derivative and the like. The photoelectric conversion layer 140 is, for example, a photoelectric conversion layer having sensitivity to specific visible light. Alternatively, the photoelectric conversion layer 140 may be a photoelectric conversion layer having sensitivity to infrared light.

The counter electrode 150 is an example of a second electrode located above the semiconductor substrate 110. The counter electrode 150 collects charges that are not used as signal charges among the electrons and holes generated in the photoelectric conversion layer 140. The counter electrode 150 contains a conductive material capable of transmitting light. The counter electrode 150 is formed of, for example, indium tin oxide (ITO).

In the present embodiment, the counter electrode 150 overlaps the pixel electrode 160 and the charge storage electrode 190 in a plan view. Specifically, the counter electrode 150 faces the pixel electrode 160 via the photoelectric conversion layer 140, the semiconductor layer 130, and the blocking layer 170.

The pixel electrode 160 is an example of a third electrode that is arranged apart from the photoelectric conversion layer 140 and is electrically connected to the photoelectric conversion layer 140 via the semiconductor layer 130. The pixel electrode 160 is located above the semiconductor substrate 110. Specifically, the pixel electrode 160 is provided in contact with the upper surface of the insulating layer 120. The side surface of the pixel electrode 160 is in contact with the semiconductor layer 130. The upper surface of the pixel electrode 160 is covered with the blocking layer 170 and is not in contact with the semiconductor layer 130.

The pixel electrode 160 contains, for example, titanium nitride (TiN). Elemental Ti and compounds of Ti are chemically stable. Therefore, it is unlikely that the simple substance or compound of Ti is decomposed and adversely affects the semiconductor layer 130. The pixel electrode 160 may include other metal nitrides such as tantalum nitride (TaN).

The pixel electrode 160 is electrically connected to the diffusion region 180. Specifically, the pixel electrode 160 is electrically connected to the diffusion region 180 and the charge detection circuit (not shown) via the plug 161 provided in the insulating layer 120 and the wiring layer 181. The plug 161 has conductivity and penetrates the insulating layer 120. The plug 161 electrically connects the pixel electrode 160 and the diffusion region 180. The plug 161 includes a barrier metal film made of a metal nitride film such as TaN or TiN, and a metal film made of copper (Cu) or tungsten (W). The barrier metal film is interposed between the metal film and the insulating layer 120, and suppresses the material constituting the metal film from diffusing into the insulating layer 120.

The blocking layer 170 is located between the photoelectric conversion layer 140 and the pixel electrode 160, and overlaps at least a part of the pixel electrode 160 in a plan view. In this embodiment, the blocking layer 170 is located between the semiconductor layer 130 and the pixel electrode 160. Specifically, the blocking layer 170 is provided in contact with the upper surface of the pixel electrode 160.

The blocking layer 170 overlaps the pixel electrode 160 in a plan view. For example, the contour of the blocking layer 170 coincides with the contour of the pixel electrode 160 in a plan view. That is, the side surface of the blocking layer 170 and the side surface of the pixel electrode 160 are flush with each other.

The blocking layer 170 blocks the signal charge generated in the photoelectric conversion layer 140. Specifically, the blocking layer 170 suppresses the signal charge from moving to the pixel electrode 160 at a timing other than a predetermined timing.

The blocking layer 170 may have a light-shielding property. Since the blocking layer 170 has a light-shielding property, when the incident light is not sufficiently absorbed in the photoelectric conversion layer 140, it is possible to suppress the color mixing caused by being reflected by the pixel electrode 160 and propagated to the adjacent pixels. Can be done.

The blocking layer 170 has an insulating property. The blocking layer 170 is, for example, a monolayer film containing one of TEOS, silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, hafnium silicate, zirconium silicate, hafnium oxide, zirconia, and the like, or among these. It is a laminated film containing two or more types. As the blocking layer 170 having a light-shielding property, for example, an insulating resin material in which carbon black or an organic pigment is dispersed can be used.

The blocking layer 170 only needs to be able to block the signal charge, and does not have to block the charge having the opposite polarity to the signal charge. For example, when holes are used as signal charges, the blocking layer 170 may be a hole blocking layer that blocks holes and allows electrons to pass through. Alternatively, when electrons are used as signal charges, the blocking layer 170 may be an electron blocking layer that blocks electrons and allows holes to pass through.

The charge storage electrode 190 is an example of a first electrode located above the semiconductor substrate 110. The charge storage electrode 190 faces the counter electrode 150 via the photoelectric conversion layer 140 and the semiconductor layer 130. The charge storage electrode 190 is used to store a charge to be used as a signal charge among the electrons and holes generated in the photoelectric conversion layer 140.

At least a portion of the charge storage electrode 190 does not overlap the blocking layer 170 in plan view. In the present embodiment, the charge storage electrode 190 does not completely overlap the blocking layer 170 in a plan view. That is, in a plan view, the blocking layer 170 and the charge storage electrode 190 are provided apart from each other without overlapping. The charge storage electrode 190 is larger than the pixel electrode 160 in a plan view, for example.

A color filter, a microlens, or the like may be provided on the sealing film 151. Further, a light-shielding film may be provided in the direction directly above the pixel electrode 160, that is, at a position overlapping the pixel electrode 160 in a plan view. The light-shielding film may be provided on the upper surface of the sealing film 151, for example.

[motion]
Next, the operation of the image pickup apparatus 100 according to the present embodiment will be described.

The operation of the image pickup apparatus 100 according to the present embodiment includes an exposure step of accumulating signal charges and a readout step of reading out the accumulated signal charges. The readout step is performed after the exposure step.

In the exposure step, when holes are used as signal charges, the potential of the counter electrode 150 is set higher than that of the charge storage electrode 190. For example, a voltage about 10 V higher than the potential of the charge storage electrode 190 is applied to the counter electrode 150. As a result, of the electrons and holes generated in the photoelectric conversion layer 140, the holes are attracted to the charge storage electrode 190 and accumulated at the boundary portion between the semiconductor layer 130 and the insulating layer 120. The electrons are collected by the counter electrode 150.

After that, in the readout step, by setting the potential of the charge storage electrode 190 higher than that of the pixel electrode 160, the holes accumulated at the boundary between the insulating layer 120 and the semiconductor layer 130 above the charge storage electrode 190 are removed. It can be transferred to the diffusion region 180 via the pixel electrode 160 at a predetermined timing. For example, a voltage about 3 V higher than the potential of the pixel electrode 160 is applied to the charge storage electrode 190. The holes transferred to the diffusion region 180 are read out by the charge detection circuit.

As the signal charge, electrons may be used. When electrons are used, if the potential difference between the charge storage electrode 190 and each of the counter electrode 150 and the pixel electrode 160 is set to the opposite polarity when holes are used, the potential applied to each electrode is set. good.

According to the image pickup apparatus 100 according to the present embodiment, in the exposure process, a region in the photoelectric conversion layer 140 that is located directly above the pixel electrode 160, that is, a region that overlaps the pixel electrode 160 in a plan view. The generated signal charge is blocked by the blocking layer 170 even if light is incident on it. That is, even if the signal charge moves from the photoelectric conversion layer 140 to the semiconductor layer 130, it does not reach the upper surface of the pixel electrode 160 as it is because the blocking layer 170 covers the upper surface of the pixel electrode 160. The signal charge is attracted by the voltage applied to the charge storage electrode 190 and is stored in the upper region of the charge storage electrode 190.

By providing the blocking layer 170 in this way, it is possible to suppress the signal charge from moving to the pixel electrode 160 in the exposure process. Therefore, it is possible to prevent the electric charge from being mixed into the electric charge detection circuit at an undesired timing. As described above, according to the image pickup apparatus 100 according to the present embodiment, it is possible to suppress noise caused by the mixing of electric charges.

[Production method]
Next, a method of manufacturing the image pickup apparatus 100 according to the present embodiment will be described with reference to FIGS. 2 to 7.

2 to 7 are cross-sectional views showing each step of the manufacturing method of the image pickup apparatus 100 according to the first embodiment, respectively. In the following description, the forming process will be mainly described. The manufacturing process of the semiconductor substrate 110, the diffusion region 180, the charge detection circuit (not shown), and the wiring layer 181 including the charge storage electrode 190 are the same as those of the normal logic CMOS manufacturing process. Therefore, the description thereof will be omitted.

First, as shown in FIG. 2, an insulating layer 120 is formed above the wiring layer 181 by using, for example, a chemical vapor deposition (CVD) method. Subsequently, a resist pattern is formed above the insulating layer 120 by using a lithography method. The resist pattern has a via pattern for forming the plug 161. By dry etching, vias are formed on the insulating layer 120 to expose the upper surface of the wiring layer 181. After that, the resist pattern is removed by ashing.

Subsequently, the metal material constituting the plug 161 is deposited by using a CVD method, a physical vapor deposition (PVD) method, or the like, and then the upper surface of the insulating layer 120 is formed by using a chemical mechanical polishing (CMP) method. Flatten. This forms the plug 161 as shown in FIG. The upper surface of the plug 161 and the upper surface of the insulating layer 120 are flush with each other.

Next, by repeating the CVD method, the lithography method, and the dry etching, the pixel electrode 160 and the blocking layer 170 are formed in this order as shown in FIG. For example, a conductive film such as a titanium nitride film constituting the pixel electrode 160 and an insulating film constituting the blocking layer 170 are formed in order, and then the insulating film and the conductive film are continuously patterned by a lithography method and dry etching. do. As a result, the shape and size of the pixel electrode 160 and the blocking layer 170 in a plan view can be made substantially the same. The conductive film constituting the pixel electrode 160 may be formed by a sputtering method.

Next, the semiconductor layer 130 is formed as shown in FIG. 5 by using a CVD method, a sputtering method, or the like. In the present embodiment, a semiconductor film constituting the semiconductor layer 130 is formed on the entire upper surface of the insulating layer 120 so as to cover the pixel electrode 160 and the blocking layer 170. By polishing and flattening the upper surface of the formed semiconductor film, the semiconductor layer 130 having a flat upper surface is formed. The upper surface of the semiconductor layer 130 does not have to be flat, and irregularities due to the pixel electrodes 160 and the blocking layer 170 may be formed.

Next, the photoelectric conversion layer 140 is formed as shown in FIG. 6 by using a vacuum vapor deposition method, a spin coating method, or the like.

Next, the counter electrode 150 is formed as shown in FIG. 7 by using a sputtering method or the like.

Then, the sealing film 151 is formed by using an atomic layer deposition method, a CVD method, or the like. The sealing film 151 is formed of, for example, aluminum oxide (AlO) or silicon oxide nitride (SiON).

As described above, the image pickup apparatus 100 shown in FIG. 1 is manufactured.

(Embodiment 2)
Subsequently, the image pickup apparatus according to the second embodiment will be described. In the image pickup apparatus according to the second embodiment, the position and size of the blocking layer provided are mainly different from those of the first embodiment. In the following, the differences from the first embodiment will be mainly described, and the common points will be omitted or simplified.

FIG. 8 is a cross-sectional view of the image pickup apparatus 200 according to the present embodiment. As shown in FIG. 8, the image pickup apparatus 200 according to the present embodiment includes a blocking layer 270 instead of the blocking layer 170 as compared with the imaging apparatus 100 according to the first embodiment.

The blocking layer 270 is located between the photoelectric conversion layer 140 and the semiconductor layer 130. Specifically, the blocking layer 270 is provided in contact with the flat upper surface of the semiconductor layer 130.

The blocking layer 270 overlaps with the pixel electrode 160 in a plan view. In the present embodiment, the blocking layer 270 has a larger area than the pixel electrode 160 in a plan view and overlaps the entire pixel electrode 160. That is, in a plan view, the entire pixel electrode 160 is located inside the contour of the pixel electrode 160. The shape and size of the blocking layer 270 in a plan view may be the same as that of the pixel electrode 160.

Further, the blocking layer 270 does not overlap with at least a part of the charge storage electrode 190 in a plan view. In the present embodiment, the end of the blocking layer 270 closest to the charge storage electrode 190 is close to the end of the charge storage electrode 190 close to the pixel electrode 160. Specifically, in a plan view, a part of the contour of the blocking layer 270 coincides with a part of the contour of the charge storage electrode 190. Although some of the contours coincide with each other, the blocking layer 270 and the charge storage electrode 190 do not overlap each other in a plan view.

The operation of the image pickup apparatus 200 is the same as the operation of the image pickup apparatus 100 according to the first embodiment. Therefore, in the exposure step, the blocking layer 270 suppresses the signal charge generated in the photoelectric conversion layer 140 from moving to the pixel electrode 160 at a timing other than the timing of reading. As a result, according to the image pickup apparatus 200, it is possible to suppress noise caused by the mixing of electric charges, similarly to the image pickup apparatus 100.

The manufacturing method of the imaging device 200 is the same as the manufacturing method of the imaging device 100 according to the first embodiment. In the step shown in FIG. 4, only the pixel electrode 160 is formed, the semiconductor layer 130 shown in FIG. 5 is formed, and then the blocking layer 270 is formed. As a result, the image pickup apparatus 200 according to the present embodiment is manufactured.

(Embodiment 3)
Subsequently, the image pickup apparatus according to the third embodiment will be described. In the image pickup apparatus according to the third embodiment, the position and size of the blocking layer and the shape of the semiconductor layer are mainly different from those of the first and second embodiments. In the following, the differences from the first and second embodiments will be mainly described, and the common points will be omitted or simplified.

FIG. 9 is a cross-sectional view of the image pickup apparatus 300 according to the present embodiment. As shown in FIG. 9, the image pickup apparatus 300 according to the present embodiment has a semiconductor layer 330 and a blocking layer instead of the semiconductor layer 130 and the blocking layer 170 as compared with the imaging apparatus 100 according to the first embodiment. It is equipped with 370.

The semiconductor layer 330 does not cover the upper surface of the pixel electrode 160, but covers the side surface thereof. Specifically, the upper surface of the semiconductor layer 330 and the upper surface of the pixel electrode 160 are flush with each other. The thickness of the semiconductor layer 330 and the thickness of the pixel electrode 160 are equal to each other.

The blocking layer 370 is located between the photoelectric conversion layer 140 and the pixel electrode 160. Specifically, the blocking layer 370 is in contact with the photoelectric conversion layer 140 and the pixel electrode 160. The blocking layer 370 is also in contact with a part of the semiconductor layer 330.

The blocking layer 370 overlaps with the pixel electrode 160 in a plan view. In the present embodiment, the blocking layer 370 has a larger area than the pixel electrode 160 in a plan view and overlaps the entire pixel electrode 160. Specifically, the blocking layer 370 completely covers the upper surface of the pixel electrode 160 and partially covers the upper surface of the semiconductor layer 330. The blocking layer 370 is provided so as to straddle the boundary between the upper surface of the pixel electrode 160 and the upper surface of the semiconductor layer 330. The shape and size of the blocking layer 370 in a plan view may be the same as that of the pixel electrode 160.

Further, the blocking layer 370 does not overlap with at least a part of the charge storage electrode 190 in a plan view. In the present embodiment, the end of the blocking layer 370 closest to the charge storage electrode 190 is close to the end of the charge storage electrode 190 close to the pixel electrode 160. Specifically, in a plan view, a part of the contour of the blocking layer 370 coincides with a part of the contour of the charge storage electrode 190. Although some of the contours coincide with each other, the blocking layer 370 and the charge storage electrode 190 do not overlap each other in a plan view.

The operation of the image pickup apparatus 300 is the same as the operation of the image pickup apparatus 100 according to the first embodiment. Therefore, in the exposure step, the blocking layer 370 suppresses the signal charge generated in the photoelectric conversion layer 140 from moving to the pixel electrode 160 at a timing other than the timing of reading. As a result, according to the image pickup apparatus 300, it is possible to suppress noise caused by the mixing of electric charges, similarly to the image pickup apparatus 100.

The manufacturing method of the imaging device 300 is the same as the manufacturing method of the imaging device 100 according to the first embodiment. In the step shown in FIG. 4, only the pixel electrode 160 is formed, the semiconductor layer 330 shown in FIG. 5 is formed, and then the upper surface is flattened. As a result, the upper surface of the pixel electrode 160 and the upper surface of the semiconductor layer 330 are flush with each other. After this, the blocking layer 370 is formed. As a result, the image pickup apparatus 300 according to the present embodiment is manufactured.

(Embodiment 4)
Subsequently, the image pickup apparatus according to the fourth embodiment will be described. The image pickup apparatus according to the fourth embodiment is mainly different from the first embodiment in that it includes a transfer electrode. In the following, the differences from the first to third embodiments will be mainly described, and the common points will be omitted or simplified.

FIG. 10 is a cross-sectional view of the image pickup apparatus 400 according to the present embodiment. As shown in FIG. 10, the image pickup apparatus 400 according to the present embodiment further includes a transfer electrode 490 as compared with the image pickup apparatus 100 according to the first embodiment.

The transfer electrode 490 is an example of a fourth electrode facing the counter electrode 150 via the insulating layer 120, the semiconductor layer 130, and the photoelectric conversion layer 140. It is located between the charge storage electrode 190 and the pixel electrode 160 in a plan view. The transfer electrode 490 does not overlap with either the pixel electrode 160 or the charge storage electrode 190 in a plan view. The transfer electrode 490 and the charge storage electrode 190 are provided apart from each other. In the example shown in FIG. 10, the transfer electrode 490 does not overlap with the blocking layer 170 in plan view.

The transfer electrode 490 is located in the same wiring layer 181 as the charge storage electrode 190. Specifically, the height from the semiconductor substrate 110 is the same on the upper surface of the transfer electrode 490 and the upper surface of the charge storage electrode 190. The thickness of the transfer electrode 490 and the thickness of the charge storage electrode 190 are the same as each other.

The transfer electrode 490 controls the transfer of the signal charge generated in the photoelectric conversion layer 140 to the pixel electrode 160. Specifically, the transfer electrode 490 controls the movement of the signal charge stored above the charge storage electrode 190.

For example, when holes are used as signal charges, the potential of the transfer electrode 490 is set higher than that of the charge storage electrode 190 in the exposure step. This makes it possible to prevent holes from being unintentionally transferred to the pixel electrode 160.

In the readout step, the potential of the transfer electrode 490 is set to, for example, the potential between the pixel electrode 160 and the charge storage electrode 190. As a result, the signal charge can be efficiently transferred to the diffusion region 180 via the pixel electrode 160.

In the image pickup apparatus 400 according to the present embodiment, not only noise caused by electric charge mixing can be suppressed, but also signal charge transfer efficiency can be improved.

The manufacturing method of the imaging device 400 is the same as the manufacturing method of the imaging device 100 according to the first embodiment. The transfer electrode 490 is formed of, for example, the same material and the same process as the charge storage electrode 190.

The image pickup device 400 shown in FIG. 10 has a configuration in which the image pickup device 100 according to the first embodiment further includes a transfer electrode 490, but the image pickup device 200 according to the second embodiment or the third embodiment has a configuration. The imaging device 300 may similarly include a transfer electrode 490.

FIG. 11 is a cross-sectional view of the image pickup apparatus 401 according to the first modification of the present embodiment. As shown in FIG. 11, the image pickup apparatus 401 further includes a transfer electrode 490 as compared with the image pickup apparatus 200 according to the second embodiment. Further, the image pickup apparatus 401 includes a blocking layer 470 instead of the blocking layer 270.

As shown in FIG. 11, the blocking layer 470 overlaps with the transfer electrode 490 in a plan view. Specifically, the blocking layer 470 overlaps the entire pixel electrode 160 and the transfer electrode 490 in a plan view. In plan view, the blocking layer 470 does not overlap the charge storage electrode 190. Specifically, in a plan view, a part of the contour of the blocking layer 470 coincides with a part of the contour of the charge storage electrode 190. Although some of the contours coincide with each other, the blocking layer 470 and the charge storage electrode 190 do not overlap each other in a plan view.

FIG. 12 is a cross-sectional view of the image pickup apparatus 402 according to the second modification of the present embodiment. As shown in FIG. 12, the image pickup apparatus 402 further includes a transfer electrode 490 as compared with the image pickup apparatus 300 according to the third embodiment. Further, the image pickup apparatus 402 includes a blocking layer 471 instead of the blocking layer 370.

As shown in FIG. 12, the blocking layer 471 overlaps with the transfer electrode 490 in a plan view. Specifically, the blocking layer 471 overlaps the entire pixel electrode 160 and the transfer electrode 490 in a plan view. The blocking layer 471 covers each of the upper surface of the pixel electrode 160 and a part of the upper surface of the semiconductor layer 330.

In plan view, the blocking layer 471 does not overlap the charge storage electrode 190. Specifically, in a plan view, a part of the contour of the blocking layer 471 coincides with a part of the contour of the charge storage electrode 190. Although some of the contours coincide with each other, the blocking layer 471 and the charge storage electrode 190 do not overlap each other in a plan view.

As described above, in the imaging devices 401 and 402, the blocking layers 470 and 471 overlap with the transfer electrode 490 in a plan view, respectively. Therefore, the signal charge generated in the direction directly above the blocking layer 470 or 471 wraps around the blocking layer 470 or 471 and is difficult to reach between the pixel electrode 160 and the transfer electrode 490. Mixing can be further suppressed.

(Embodiment 5)
Subsequently, the image pickup apparatus according to the fifth embodiment will be described. The image pickup apparatus according to the fifth embodiment is mainly different from the image pickup apparatus according to the first embodiment in that the semiconductor substrate includes a photoelectric conversion unit. In the following, the differences from the first embodiment will be mainly described, and the common points will be omitted or simplified.

FIG. 13 is a cross-sectional view of the image pickup apparatus 500 according to the present embodiment. In the image pickup apparatus 500 according to the present embodiment, the semiconductor substrate 110 includes a photoelectric conversion unit 510.

The photoelectric conversion unit 510 is a photoelectric conversion region formed in the semiconductor substrate 110 using an inorganic material. The photoelectric conversion unit 510 is an impurity region formed by injecting a conductive type impurity different from the conductive type of the semiconductor constituting the semiconductor substrate 110. For example, when the semiconductor substrate 110 is a p-type Si substrate, the photoelectric conversion unit 510 is a region containing n-type impurities. As a result, a pn junction is formed at the boundary between the photoelectric conversion unit 510, which is an n-type region, and the peripheral region thereof. When light is incident on the pn junction, electron-hole pairs are generated in the photoelectric conversion unit 510. That is, the photoelectric conversion unit 510 forms a pn photodiode with its surrounding region.

The p-type region around the photoelectric conversion unit 510 may have a higher p-type impurity concentration than the other regions of the semiconductor substrate 110. By adjusting the impurity concentrations of the p-type impurities and n-type impurities, the band gap of the pn junction can be adjusted, and the sensitivity of the photoelectric conversion unit can be adjusted.

In the present embodiment, the photoelectric conversion unit 510 overlaps with the charge storage electrode 190 in a plan view. In a plan view, the photoelectric conversion unit 510 has a size equivalent to that of the charge storage electrode 190. Alternatively, the photoelectric conversion unit 510 may be larger than the charge storage electrode 190 in a plan view.

The photoelectric conversion unit 510 generates and stores signal charges by light transmitted through the sealing film 151, the counter electrode 150, the photoelectric conversion layer 140, the semiconductor layer 130, the insulating layer 120, and the charge storage electrode 190 located above. Therefore, the sealing film 151, the counter electrode 150, the photoelectric conversion layer 140, the semiconductor layer 130, the insulating layer 120, and the charge storage electrode 190 all have translucency with respect to the wavelength region to be photoelectrically converted by the photoelectric conversion unit 510. The material may be selected and used.

For example, when the photoelectric conversion unit 510 is made of silicon, the photoelectric conversion unit 510 is mainly sensitive to blue light and red light. That is, the photoelectric conversion unit 510 can perform photoelectric conversion of blue light and red light. In this case, for example, a quinacridone derivative and a subphthalocyanine derivative are used as materials constituting the photoelectric conversion layer 140. As a result, the photoelectric conversion layer 140 is mainly sensitive to green light and can transmit blue light and red light. As a material constituting the semiconductor layer 130, an oxide semiconductor transparent to visible light such as InGaZnO is used. As a material constituting each of the counter electrode 150 and the charge storage electrode 190, a material transparent to visible light such as ITO is used.

As a result, green light among the light incident on the image pickup apparatus 500 can be photoelectrically converted by the photoelectric conversion layer 140, and blue light and red light can be photoelectrically converted by the photoelectric conversion unit 510. That is, it is possible to realize a color image sensor in which the photoelectric conversion layer 140 generates a signal charge for green light and the photoelectric conversion unit 510 generates a signal charge for blue light or red light. A color filter for improving the color separation performance may be provided on the sealing film 151 for each pixel.

The signal charge accumulated in the photoelectric conversion unit 510 is transferred to a diffusion region provided on the semiconductor substrate 110 via a charge transfer element (not shown) such as a transistor, and is transferred by a charge detection circuit (not shown). Read out.

The image pickup apparatus 500 according to the present embodiment can not only suppress noise caused by mixing of electric charges, but also have sensitivity to a plurality of wavelength components and can take out each signal. That is, the image pickup apparatus 500 can increase the color resolution of the image. As a result, the image pickup apparatus 500 can generate, for example, a color image.

The semiconductor substrate 110 may be provided with a plurality of photoelectric conversion units. For example, by adjusting the concentration of the injected impurities, the band gap of the pn junction can be adjusted to form a plurality of photoelectric conversion units having different sensitive wavelength regions. For example, by forming a photoelectric conversion unit having sensitivity to red light and a photoelectric conversion unit having sensitivity to blue light in a laminated manner, it is possible to realize an imaging device corresponding to three colors of RGB. Alternatively, an imaging device capable of detecting visible light and infrared light may be realized.

The image pickup apparatus 500 according to the present embodiment corresponds to a modified configuration of the image pickup apparatus 100 according to the first embodiment. In the image pickup apparatus 200, 300, 400, 401 or 402 according to the second to fourth embodiments and the modifications thereof, the semiconductor substrate 110 may include a photoelectric conversion unit 510.

(Embodiment 6)
Subsequently, the image pickup apparatus according to the sixth embodiment will be described. The image pickup apparatus according to the sixth embodiment is mainly different from the fifth embodiment in that it is a back-illuminated image pickup apparatus. In the following, the differences from the fifth embodiment will be mainly described, and the common points will be omitted or simplified.

FIG. 14 is a cross-sectional view of the image pickup apparatus 600 according to the present embodiment. The image pickup apparatus 600 according to the present embodiment is mainly different from the image pickup apparatus 500 according to the fifth embodiment in that the semiconductor substrate 110 is arranged upside down. The main surface 111 of the semiconductor substrate 110 is the back surface of the semiconductor substrate 110 in the image pickup apparatus 500 shown in FIG. The main surface 112 of the semiconductor substrate 110 is the surface of the semiconductor substrate 110 in the image pickup apparatus 500 shown in FIG. That is, a transistor or the like included in the charge detection circuit or the like is formed on the main surface 112. The diffusion region 180 is formed so as to be exposed on the main surface 112.

In the image pickup apparatus 600 according to the present embodiment, as shown in FIG. 14, the main surface 111 of the semiconductor substrate 110 has the wiring layer 181 and the insulating layer 120, and the semiconductor, similarly to the imaging apparatus 500 according to the fifth embodiment. The layer 130, the photoelectric conversion layer 140, the counter electrode 150, and the sealing film 151 are laminated in this order. A plug 161 is formed on the insulating layer 120, and a pixel electrode 160 is provided so as to cover the plug 161. Further, a blocking layer 170 is provided on the upper surface of the pixel electrode 160.

In the image pickup apparatus 600, the semiconductor substrate 110 includes a through electrode 610. The through silicon via 610 penetrates from the main surface 111 to the main surface 112 of the semiconductor substrate 110. The through silicon via 610 is formed by using, for example, a metal such as copper or a conductive material such as conductive polysilicon. In this embodiment, the pixel electrode 160 is electrically connected to the diffusion region 180 via a plug 161, a wiring layer 181 and a through electrode 610 and a wiring layer 680.

The through silicon via 610 is provided on a via penetrating the semiconductor substrate 110 and is covered with an insulating layer 611. The insulating layer 611 covers the entire periphery of the side surface of the through electrode 610 so as to prevent the through electrode 610 and the semiconductor substrate 110 from coming into contact with each other. The insulating layer 611 is composed of, for example, a single-layer film made of one of TEOS, silicon oxide, silicon nitride, silicon oxynitride, and the like, or a laminated film made of two or more of these.

The wiring layer 680, like the wiring layer 181, includes one or more interlayer insulating layers, and conductive wiring and via conductors. Wiring and via conductors are formed using a metal such as copper or a conductive material such as polysilicon. The interlayer insulating layer is formed by using an insulating material selected from the materials that can be used for the insulating layer 120.

With the above configuration, the image pickup apparatus 600 according to the present embodiment can not only suppress noise caused by electric charge mixing, but also have sensitivity to a plurality of wavelength components and can take out each signal. .. That is, the image pickup apparatus 600 can increase the color resolution of the image.

The image pickup apparatus 600 according to the present embodiment forms the photoelectric conversion unit 510, the diffusion region 180, and the like on the semiconductor substrate 110, and then forms the wiring layer 680 on the main surface 112 side. The wiring layer 680 is formed by using the same manufacturing method as that of the wiring layer 181.

Next, the semiconductor substrate 110 is made thinner by polishing the back surface of the semiconductor substrate 110 as needed. After that, a via penetrating the semiconductor substrate 110 is formed, and the side surface of the via is covered with the insulating layer 611. The via is formed by processing the semiconductor substrate 110 from the main surface 111 side by, for example, dry etching. The insulating layer 611 is formed by, for example, CVD. After that, the through electrode 610 is formed by filling the inside of the via with a conductive material.

Hereinafter, in the order described with reference to FIGS. 2 to 7, the wiring layer 181 and the insulating layer 120, the pixel electrode 160, the blocking layer 170, the semiconductor layer 130, the photoelectric conversion layer 140, the counter electrode 150, and the sealing are provided on the main surface 111 side. It forms a film 151. As a result, the image pickup apparatus 600 shown in FIG. 14 is manufactured.

The image pickup apparatus 600 according to the present embodiment corresponds to a modified configuration of the image pickup apparatus 500 according to the fifth embodiment. Similar modifications may be applied to the imaging devices 100, 200, 300, 400, 401 or 402 according to the first to fourth embodiments and the modifications thereof.

(Embodiment 7)
Subsequently, the imaging system according to the seventh embodiment will be described. The imaging system according to the seventh embodiment is a system including the imaging devices according to the first to sixth embodiments. In the following, the differences from the first to sixth embodiments will be mainly described, and the common points will be omitted or simplified.

FIG. 15 is a diagram schematically showing a configuration example of the camera system 700 according to the present embodiment. The camera system 700 is an example of an imaging system, and includes an optical system 710, an imaging device 100, a camera signal processing unit 720, and a system controller 730.

The optical system 710 includes, for example, an autofocus lens, a zoom lens, and an aperture. The optical system 710 collects light on the image pickup surface of the image pickup apparatus 100.

The camera signal processing unit 720 functions as a signal processing circuit that processes an output signal from the image pickup apparatus 100. The camera signal processing unit 720 performs processing such as gamma correction, color interpolation processing, spatial interpolation processing, and auto white balance. The camera signal processing unit 720 can be realized by, for example, a DSP (Digital Signal Processor) or the like.

The system controller 730 controls the overall operation of the camera system 700. The system controller 730 can be implemented, for example, by a microcomputer.

The camera system 700 may include the above-mentioned imaging devices 200, 300, 400, 401, 402, 500 or 600 instead of the imaging device 100. According to the camera system 700, it is possible to prevent the signal charge generated by the photoelectric conversion layer 140 from being unintentionally mixed into the charge detection circuit. Thereby, the camera system 700 can generate a good image.

(Other embodiments)
Although the image pickup apparatus and the image pickup system according to one or more embodiments have been described above based on the embodiments, the present disclosure is not limited to these embodiments. As long as the gist of the present disclosure is not deviated, various modifications that can be conceived by those skilled in the art are applied to the present embodiment, and a form constructed by combining components in different embodiments is also included in the scope of the present disclosure. Is done.

For example, the blocking layer may cover a part of the pixel electrode in a plan view, and does not necessarily cover the entire pixel electrode. That is, in a plan view, the pixel electrode may include a portion not covered by the blocking layer. Further, for example, a part of the blocking layer may overlap the charge storage electrode in a plan view.

Further, in each of the above embodiments, various changes, replacements, additions, omissions, etc. can be made within the scope of claims or the equivalent scope thereof.

The imaging apparatus and imaging system according to the present disclosure can be used for various camera systems and sensor systems such as digital still cameras, medical cameras, surveillance cameras, in-vehicle cameras, digital single-lens reflex cameras, and digital mirrorless single-lens cameras.

100, 200, 300, 400, 401, 402, 500, 600 Imaging device 110 Semiconductor substrate 111, 112 Main surface 120, 611 Insulation layer 130, 330 Semiconductor layer 140 Photoelectric conversion layer 150 Opposite electrode 151 Sealing film 160 Pixel electrode 161 Plug 170, 270, 370, 470, 471 Blocking layer 180 Diffusion region 181, 680 Wiring layer 190 Charge storage electrode 490 Transfer electrode 510 Photoelectric conversion unit 610 Penetration electrode 700 Camera system 710 Optical system 720 Camera signal processing unit 730 System controller

Claims (15)

With a semiconductor substrate
The first electrode, the insulating layer, the semiconductor layer, the photoelectric conversion layer, and the second electrode, which are located above the semiconductor substrate and are laminated in this order,
A third electrode, which is arranged apart from the photoelectric conversion layer and is electrically connected to the photoelectric conversion layer via the semiconductor layer,
A blocking layer located between the photoelectric conversion layer and the third electrode, which overlaps with at least a part of the third electrode in a plan view and blocks the signal charge generated in the photoelectric conversion layer.
With
At least a part of the first electrode does not overlap with the blocking layer in a plan view.
Imaging device. The blocking layer is located between the semiconductor layer and the third electrode.
The imaging device according to claim 1. The blocking layer is located between the photoelectric conversion layer and the semiconductor layer.
The imaging device according to claim 1. The blocking layer is in contact with the photoelectric conversion layer and the third electrode.
The imaging device according to claim 1. The blocking layer has a larger area than the third electrode in a plan view and overlaps the entire third electrode.
The imaging device according to any one of claims 1 to 4. The third electrode does not overlap with the first electrode in a plan view.
The imaging device according to any one of claims 1 to 5. The second electrode faces the third electrode via the blocking layer and the photoelectric conversion layer.
The imaging device according to any one of claims 1 to 6. The blocking layer has an insulating property.
The imaging device according to any one of claims 1 to 7. The blocking layer has a light-shielding property.
The imaging device according to any one of claims 1 to 8. A fourth electrode facing the second electrode via the insulating layer, the semiconductor layer, and the photoelectric conversion layer is further provided.
The fourth electrode is located between the first electrode and the third electrode in a plan view.
The imaging device according to any one of claims 1 to 9. The first electrode does not completely overlap the blocking layer in a plan view.
The imaging device according to any one of claims 1 to 10. The semiconductor substrate includes a photoelectric conversion unit that overlaps with the first electrode in a plan view.
The imaging device according to any one of claims 1 to 11. The semiconductor substrate includes a diffusion region and contains a diffusion region.
The third electrode is electrically connected to the diffusion region.
The imaging device according to any one of claims 1 to 12. The semiconductor substrate further includes through electrodes that penetrate from one surface to the other.
The third electrode is electrically connected to the diffusion region via the through electrode.
The imaging device according to claim 13. The imaging device according to any one of claims 1 to 14.
An optical system that collects light on the image pickup device,
A processing circuit that processes the signal output by the image pickup device, and
To prepare
Imaging system.

Images