JP2008218787A - Image pick-up device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image pick-up device having a photoelectrically converting part on a substrate and a photoelectrically converting part within a substrate, wherein it is possible to materialize a low cost, a low noise and a thin type, while being able to enhance a sensitivity of the photoelectrically converting part on the substrate. <P>SOLUTION: The image pick-up device has, on a coplanar face, a plurality of pixel parts which contain a photoelectrically converting part on a substrate 3 which contains a lower electrode 4 formed above a semiconductor substrate 1, an upper electrode 6 formed above the lower electrode 4, and a photoelectrically converting film 5 sandwiched between the lower electrode 4 and the upper electrode 6; and a photoelectrically converting part within a substrate 7 formed in the semiconductor substrate 1 below the photoelectrically converting part on the substrate 3. The lower electrode 4 has a reflection part for reflecting an incident light incident from above the upper electrode 6 (a portion except an opening part K) and a transmission part for transmitting the incident light (the opening part K). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention provides an on-substrate photoelectric conversion unit including a lower electrode formed above a semiconductor substrate, an upper electrode formed above the lower electrode, and a photoelectric conversion film sandwiched between the lower electrode and the upper electrode, The present invention relates to an imaging device having a plurality of pixel portions on the same plane including an in-substrate photoelectric conversion portion formed inside the semiconductor substrate below the photoelectric conversion portion on the substrate.

  Patent Document 1 discloses a photoelectric conversion unit on a substrate including a lower electrode formed above a semiconductor substrate, an upper electrode formed above the lower electrode, and a photoelectric conversion film sandwiched between the lower electrode and the upper electrode. In the imaging device having a plurality of pixel units on the same plane including the in-substrate photoelectric conversion unit formed inside the semiconductor substrate below the on-substrate photoelectric conversion unit, the on-substrate photoelectric conversion unit and the in-substrate photoelectric conversion unit The charge generated in the photoelectric conversion unit on the substrate is provided with an optical thin film that reflects light in the wavelength range absorbed by the photoelectric conversion film and transmits light in the wavelength range absorbed by the photoelectric conversion unit in the substrate. A technique for improving the sensitivity by increasing the amount is disclosed.

JP 2006-270021 A

  In the imaging device disclosed in Patent Document 1, a charge accumulation unit for accumulating charges generated in a photoelectric conversion unit on a substrate is provided in a semiconductor substrate, and the accumulated charges are signaled by a known CMOS circuit or the like. However, since an optical thin film exists between the semiconductor substrate and the photoelectric conversion portion on the substrate, unnecessary stray capacitance is generated. As a result, the noise of the output signal increases. In addition, since it is necessary to form an optical thin film between the semiconductor substrate and the photoelectric conversion portion on the substrate, the device manufacturing process becomes complicated, or the thickness of the device increases.

  The present invention has been made in view of the above circumstances, and is an image pickup device having an on-substrate photoelectric conversion unit and an in-substrate photoelectric conversion unit, and realizes low cost, low noise, and thinning while the substrate is realized. An object is to provide an imaging device capable of improving the sensitivity of the upper photoelectric conversion unit.

  An image sensor according to the present invention includes a lower electrode formed above a semiconductor substrate, an upper electrode formed above the lower electrode, and a photoelectric conversion unit on a substrate including a photoelectric conversion film sandwiched between the lower electrode and the upper electrode. And a plurality of pixel portions on the same plane including the in-substrate photoelectric conversion portion formed inside the semiconductor substrate below the on-substrate photoelectric conversion portion, wherein the upper electrode is located above the upper electrode. The transparent electrode is transparent to the incident light incident on the lower electrode, and the lower electrode has a reflection part that reflects the incident light and a transmission part that transmits the incident light.

  In the imaging device according to the aspect of the invention, the lower electrode includes a conductive reflective material film that reflects the incident light, and the lower electrode includes an opening formed in the reflective material film. The reflection part is formed, and the transmission part is formed by the opening.

  In the imaging element of the present invention, a conductive material transparent to the incident light is embedded in the opening.

  In the imaging device of the present invention, the transmission part is formed immediately above the in-substrate photoelectric conversion part.

  In the imaging device according to the aspect of the invention, the pixel unit includes an optical system for condensing the light transmitted through the transmission unit on the photoelectric conversion unit in the substrate between the photoelectric conversion unit on the substrate and the semiconductor substrate. .

  In the imaging device of the present invention, the pixel unit includes a microlens for concentrating incident light on the transmission unit above the photoelectric conversion unit on the substrate.

  The image pickup device of the present invention includes an arbitrary photoelectric conversion unit on the substrate between the photoelectric conversion film of the optional photoelectric conversion unit on the substrate and the photoelectric conversion film of the adjacent photoelectric conversion unit on the substrate. A light incident preventing member is provided for preventing light transmitted through the photoelectric conversion film from entering the photoelectric conversion film of the photoelectric conversion unit on the adjacent substrate.

  In the imaging device of the present invention, the light incident preventing member is made of a reflective material that reflects the incident light.

  According to the present invention, an image sensor having a photoelectric conversion unit on a substrate and an in-substrate photoelectric conversion unit, which improves the sensitivity of the photoelectric conversion unit on the substrate while realizing low cost, low noise, and thinning. It is possible to provide an imaging device that can handle the above-described problem.

  Embodiments of the present invention will be described below with reference to the drawings. In the following description, “to be transparent to light” means to transmit 50% or more of light.

(First embodiment)
1A and 1B are diagrams illustrating a schematic configuration of one pixel portion of the image sensor according to the first embodiment of the present invention, in which FIG. 1A is a schematic cross-sectional view of one pixel portion, and FIG. 1B is a lower portion illustrated in FIG. It is a top view of an electrode. The image sensor according to the present embodiment is obtained by arranging a plurality of pixel portions having the configuration shown in FIG. 1A on the same plane.
1A includes a photoelectric conversion unit 3 on a substrate formed on a semiconductor substrate 1 such as silicon via an insulating film 2 that is transparent to incident light, and a photoelectric conversion on the substrate. And an in-substrate photoelectric conversion unit 7 formed in the semiconductor substrate 1 below the conversion unit 3.

  The on-substrate photoelectric conversion unit 3 includes a lower electrode 4 formed on the insulating film 2, a photoelectric conversion film 5 formed above the lower electrode 4, and an upper electrode 6 formed above the photoelectric conversion film 5. It has a configuration.

Incident light enters the upper electrode 6 from above. The upper electrode 6 is made of a conductive material that is transparent to the incident light because incident light needs to be incident on the photoelectric conversion film 5. As the material of the upper electrode 6, a transparent conductive oxide (TCO) having a high transmittance for visible light and infrared light and a small resistance value can be preferably used. A metal thin film such as Au can also be used. However, if an attempt is made to obtain a transmittance of 90% or more, the resistance value increases drastically, so TCO is preferable. In particular, ITO, IZO, AZO, FTO, SnO ₂ , TiO ₂ , ZnO _{2 and the} like can be preferably used as TCO. The upper electrode 6 has a single configuration common to all the pixel portions, but may be divided for each pixel portion.

  The photoelectric conversion film 5 includes an organic photoelectric conversion material or an inorganic photoelectric conversion material, absorbs light in a specific wavelength region of incident light, and generates a charge corresponding to the absorbed light. The photoelectric conversion film 5 has a single-layer configuration common to all the pixel portions, but may be divided for each pixel portion. In the present embodiment, the photoelectric conversion material 5 uses a photoelectric conversion material having an absorption peak wavelength of an absorption spectrum between the visible region and the infrared region in the infrared region (wavelength of about 700 nm or more). An example of such a material is tin phthalocyanine.

  The lower electrode 4 is a thin film divided for each pixel portion, and is composed of a conductive reflective material film that reflects incident light. The material of the lower electrode 4 is preferably a highly light-shielding material so as to function as a light-shielding film that shields light from entering other parts of the semiconductor substrate 1 other than the in-substrate photoelectric conversion unit 7. In order to reflect as much light incident on the photoelectric conversion film 5 as possible, it is preferable to use a material having a high reflectance. Aluminum, silver, or the like can be preferably used as a material that satisfies such conditions.

As shown in FIG. 1B, an opening K is formed in the lower electrode 4 at a position directly above the in-substrate photoelectric conversion unit 7, and the opening K is transparent to incident light. It is filled with a material (for example, SiO ₂ ).

  Thus, the lower electrode 4 can reflect a part of incident light that passes through the photoelectric conversion film 5 and reaches the lower electrode 4 to the photoelectric conversion film 5 side, and the rest is photoelectric conversion in the substrate. The configuration is such that it can be transmitted through the portion 7. In the plan view of the lower electrode 4 shown in FIG. 1B, the opening K is a transmission part that transmits incident light, and the other part is a reflection part that reflects incident light. Can be said to have a structure having a reflection part and a transmission part.

  By applying a predetermined bias voltage between the upper electrode 6 and the lower electrode 4, one of the charges (holes, electrons) generated in the photoelectric conversion film 5 is moved to the upper electrode 6, and the other is moved to the lower electrode. 4 can be moved. In the present embodiment, a wiring is connected to the upper electrode 6, and a bias voltage is applied to the upper electrode 6 through this wiring. In addition, the polarity of the bias voltage is determined so that holes generated in the photoelectric conversion film 5 move to the upper electrode 6 and electrons move to the lower electrode 4.

  In the semiconductor substrate 1 below the reflecting portion of the lower electrode 4, a charge accumulating portion 8 for accumulating charges generated in the photoelectric conversion film 5 is formed. A via plug 11 made of a conductive material such as aluminum embedded in the insulating film 2 is formed on the charge storage portion 8, and a lower electrode 4 is formed on the via plug 11. The charge storage unit 8 is electrically connected.

  The in-substrate photoelectric conversion unit 7 is a known pn junction photodiode, absorbs light incident through the opening K of the lower electrode 4 and generates charges corresponding to the absorbed light. Accumulate.

  In the semiconductor substrate 1 and on the surface of the semiconductor substrate 1, a signal reading unit 9 for reading a signal corresponding to the electric charge generated and accumulated in the in-substrate photoelectric conversion unit 7, and a charge corresponding to the electric charge accumulated in the electric charge accumulating unit 8. A signal reading unit 10 for reading a signal is formed. The signal read-out units 9 and 10 are each composed of a known CMOS circuit, convert the accumulated charges into a signal corresponding to the amount, and output the signal. The signal reading units 9 and 10 may be configured such that charges are transferred to an amplifier by a CCD and a signal corresponding to the amount of charge is output by the amplifier.

  The in-substrate photoelectric conversion unit 7 is a pn junction photodiode. However, since the pn junction photodiode has a broad absorption spectrum characteristic with respect to light in the visible region (wavelength 400 to 680 nm), it is obtained from the signal readout unit 9. The generated signal makes it possible to generate an image (monochrome image) corresponding to visible light. Further, since the photoelectric conversion film 5 is made of a material that mainly absorbs light in the infrared region, an image (infrared image) corresponding to the infrared light is generated by a signal obtained from the signal reading unit 10. Is possible.

The operation of the image sensor having the above configuration will be described.
When the exposure period is started, infrared light of incident light is absorbed by the photoelectric conversion film 5, and charges corresponding to the amount of infrared light are generated here. Due to the bias voltage applied between the upper electrode 6 and the lower electrode 4, electrons generated in the photoelectric conversion film 5 move to the lower electrode 4, and then move to the charge storage unit 8 through the via plug 11. Accumulated in. Of the infrared light, the light that has not been absorbed by the photoelectric conversion film 5 and has reached the reflection part of the lower electrode 4 is reflected by the reflection part and is incident on the photoelectric conversion film 5 again. The electrons generated in the photoelectric conversion film 5 by the reflected light are also accumulated in the charge accumulation unit 8. On the other hand, light that has passed through the opening K of the incident light passes through the insulating film 2 and enters the in-substrate photoelectric conversion unit 7 where electrons corresponding to the amount of incident light are generated and accumulated.

  After the exposure period, a signal corresponding to the electrons accumulated in the charge accumulation unit 8 (referred to as an infrared signal because it is a signal corresponding to infrared light) and an electron accumulated in the in-substrate photoelectric conversion unit 7 A signal (referred to as a visible signal because it is a signal corresponding to visible light) is output to the outside of the image sensor, and an infrared image corresponding to the infrared signal and a visible signal are displayed by a signal processing unit of an image pickup apparatus equipped with the image sensor. A black and white image corresponding to the signal is obtained.

  Thus, according to the imaging device of the present embodiment, an infrared image and a black and white image can be acquired for the same subject at the same time, and thus, for example, it is useful as an imaging device for an endoscope.

  Further, according to the imaging device of the present embodiment, a part of the light that reaches the lower electrode 4 without being completely absorbed by the photoelectric conversion film 5 is reflected and reenters the photoelectric conversion film 5, so that the lower electrode 4 is transparent. Compared with the conventional electrode, the amount of charge generated in the photoelectric conversion film 5 can be increased, and the sensitivity can be improved.

  Further, according to the imaging device of the present embodiment, since the lower electrode 4 itself has a reflection function, it is necessary to provide an optical thin film between the semiconductor substrate 1 and the photoelectric conversion unit 3 on the substrate as in the past. As compared with the prior art, the output noise can be reduced, the thickness from the semiconductor substrate 1 to the lower electrode 4 can be reduced, and the manufacturing process can be facilitated.

  Further, according to the imaging device of the present embodiment, the lower electrode 4 can function as a light shielding film for shielding the charge storage unit 8 and the signal readout units 9 and 10, so that a new light shielding is provided above the semiconductor substrate 1. There is no need to provide a film, and the thickness from the semiconductor substrate 1 to the lower electrode 4 can be made thinner than before. By making this thickness thin, the incidence efficiency of the light transmitted through the opening K to the in-substrate photoelectric conversion unit 7 can be increased, and an improvement in sensitivity at the in-substrate photoelectric conversion unit 7 can also be expected.

  Further, the opening K of the lower electrode 4 of the image pickup device of the present embodiment can be formed at the same time as the patterning process for dividing the lower electrode 4 for each pixel portion, and the manufacture of the image pickup device is facilitated.

  Further, according to the image sensor of this embodiment, since the photoelectric conversion film 5 serves as an infrared cut filter, the image sensor equipped with the image sensor does not require an infrared cut filter, and the image sensor can be downsized. It becomes.

  In addition, the photoelectric conversion part 7 in a board | substrate is the depth which absorbs the light (R light) of a red wavelength range, and the light (G light) of a green wavelength range as described in Japanese translations of PCT publication No. 2002-513145 gazette. A pn junction surface may be formed at a depth that absorbs light and a depth that absorbs light in the blue wavelength range (B light), so that charges of three color components can be accumulated. By doing so, it is possible to realize an imaging device capable of simultaneously capturing an infrared image and a color image.

  Further, the in-substrate photoelectric conversion unit 7 is configured such that a pn junction surface is formed at a depth that absorbs R light and a depth that absorbs B light so that charges of two color components can be accumulated. The conversion film 5 may be composed of a photoelectric conversion material that mainly absorbs G light. By doing so, it is possible to realize an image sensor that can capture a color image.

  Further, there may be a plurality of openings K provided in the lower electrode 4. Since the amount of light incident on the photoelectric conversion film 5 and the in-substrate photoelectric conversion unit 7 can be adjusted by adjusting the number and area of the openings K, the on-substrate photoelectric conversion unit 3 and the in-substrate photoelectric conversion unit. 7 sensitivity can be adjusted. When it is desired to make the sensitivity of the in-substrate photoelectric conversion unit 7 and the on-substrate photoelectric conversion unit 3 structurally not by signal processing, it is effective to provide a plurality of openings K or to increase the area. It becomes.

(Second embodiment)
In the image pickup device shown in FIG. 1, since no conductive material is present in the opening K of the lower electrode 4, when a bias voltage is applied between the upper electrode 6 and the lower electrode 4, Thus, it becomes difficult to apply a bias voltage to the photoelectric conversion film 5. As a result, the charge generated in the photoelectric conversion film 5 above the opening K does not easily reach the lower electrode 4, and the amount of charge that can be acquired from the photoelectric conversion film 5 decreases. Therefore, in the present embodiment, measures are taken to prevent such a decrease in charge amount.

  2A and 2B are diagrams showing a schematic configuration of one pixel portion of an image pickup device according to the second embodiment of the present invention. FIG. 2A is a schematic sectional view of the one pixel portion, and FIG. 2B is a lower portion shown in FIG. It is a top view of an electrode. The image sensor according to the present embodiment is obtained by arranging a plurality of pixel portions having the configuration shown in FIG. 2A on the same plane. In FIG. 2, the same components as those in FIG.

The pixel portion of the image sensor shown in FIG. 2 has a configuration in which the opening K of the lower electrode 4 of the image sensor shown in FIG. 1 is filled with a conductive material 12 that is transparent to incident light. As the conductive material 12, a transparent conductive oxide (TCO) having a high transmittance for visible light and a small resistance value can be preferably used. A metal thin film such as Au can also be used. However, if an attempt is made to obtain a transmittance of 90% or more, the resistance value increases drastically, so TCO is preferable. In particular, ITO, IZO, AZO, FTO, SnO ₂ , TiO ₂ , ZnO _{2 and the} like can be preferably used as TCO.

  The configuration as shown in FIG. 2 makes it possible to apply a bias voltage uniformly to the entire photoelectric conversion film 5, and the amount of charge that can be acquired from the photoelectric conversion film 5 compared to the configuration shown in FIG. 1. Can be increased. In order to embed the conductive material 12 in the opening K, as shown in FIG. 3, after forming the conductive material 12 on the lower electrode 4 in which the opening K is formed, the lower electrode 4 is formed by CMP or the like. It is necessary to planarize the conductive material film 12 until it is exposed. However, since the conductive material 12 is transparent to incident light, the photoelectric conversion film 5 and the upper electrode 6 are formed on the conductive material film 12 in the state shown in FIG. It may be completed.

(Third embodiment)
In the imaging device shown in FIGS. 1 and 2, the light incident on the opening K of the lower electrode 4 is not incident on the in-substrate photoelectric conversion unit 7 depending on the incident angle, and thus the in-substrate photoelectric conversion unit. There is a possibility that the amount of charge that can be acquired from the light source 7 will be reduced, or light that has not been incident may be incident on the charge storage unit 8 or the signal readout units 9 and 10 and become noise. In order to prevent this noise, a light-shielding film may be provided separately. However, in this case, thinning of the element is hindered. Therefore, the image pickup device of the present embodiment eliminates the noise and increases the amount of charge that can be acquired from the in-substrate photoelectric conversion unit 7. In the image pickup device shown in FIGS. Is configured to be provided between the on-substrate photoelectric conversion unit 3 and the semiconductor substrate 1.

  4A and 4B are diagrams illustrating a schematic configuration of one pixel portion of an image sensor that is the third embodiment of the present invention, in which FIG. 4A illustrates a first configuration example, and FIG. 4B illustrates a second configuration example. (C) shows a third configuration example, and (d) shows a fourth configuration example. In FIG. 4, the same components as those in FIG. In FIG. 4, the optical system is added to the configuration in which the conductive material 12 is embedded in the opening K, but, of course, a configuration in which a transparent insulating film is embedded in the opening K may be used.

  The imaging device shown in FIG. 4A has a configuration in which an optical waveguide 13 is added as an optical system to the configuration of the imaging device shown in FIG. The optical waveguide 13 is embedded in the insulating film 2 and is made of an insulating material that is transparent to incident light and has a higher refractive index than the insulating film 2. The optical waveguide 13 has one end connected to the entire surface of the opening K and the other end connected to the entire surface of the in-substrate photoelectric conversion unit 7. The optical waveguide 13 can employ a structure used in a known single-plate image sensor. With this configuration, light obliquely incident on the opening K is guided to the in-substrate photoelectric conversion unit 7 while repeating total reflection at the interface between the optical waveguide 13 and the insulating film 2. For this reason, most of the light incident on the opening K can be guided to the in-substrate photoelectric conversion unit 7.

  The imaging device shown in FIG. 4B has a configuration in which a microlens 14 is added to the configuration of the imaging device shown in FIG. The microlens 14 condenses incident light on the opening K, and is formed on the upper electrode 6 of each pixel portion. With the microlens 14, most of the incident light that can be received by the pixel portion can be condensed at the opening K. For this reason, by combining with the optical waveguide 13, most of the incident light that has not been absorbed by the photoelectric conversion film 5 can be incident on the in-substrate photoelectric conversion unit 7. In addition, the structure which does not provide the optical waveguide 13 in FIG.4 (b) may be sufficient. Even in such a configuration, a larger amount of light can be incident on the in-substrate photoelectric conversion unit 7 than in the configuration shown in FIGS.

  The image pickup device shown in FIG. 4C has a configuration in which an inner lens 15 is added as an optical system to the configuration of the image pickup device shown in FIG. The inner lens 15 is a lens embedded in the insulating film 2 in order to collect the light transmitted through the opening K on the in-substrate photoelectric conversion unit 7. The inner lens 15 can employ a structure used in a known single-plate image sensor. With this configuration, light obliquely incident on the opening K is condensed by the inner lens 15 onto the in-substrate photoelectric conversion unit 7, so that most of the light incident on the opening K enters the in-substrate photoelectric conversion unit 7. It can be made incident.

  The imaging device shown in FIG. 4D has a configuration in which a microlens 14 is added to the configuration of the imaging device shown in FIG. The microlens 14 condenses incident light on the opening K, and is formed on the upper electrode 6 of each pixel portion. With the microlens 14, most of the incident light that can be received by the pixel portion can be condensed at the opening K. For this reason, by combining with the inner lens 15, most of the incident light that has not been absorbed by the photoelectric conversion film 5 can be incident on the in-substrate photoelectric conversion unit 7.

  As described above, according to the configuration illustrated in FIG. 4, most of the light incident on the opening K can be incident on the in-substrate photoelectric conversion unit 7, so that the amount of charge that can be acquired from the in-substrate photoelectric conversion unit 7. 1 can be increased as compared with the configuration shown in FIGS. 1 and 2, and an improvement in sensitivity can be realized. Further, since it is possible to prevent the light transmitted through the opening K from reaching other than the in-substrate photoelectric conversion unit 7, noise can be reduced as compared with the configuration shown in FIGS. Further, since noise can be reduced without providing a light shielding film, the imaging element can be made thinner.

(Fourth embodiment)
FIG. 5 is a diagram showing a schematic configuration of one pixel portion of an image sensor that is the fourth embodiment of the present invention. In FIG. 5, the same components as those in FIG.
The imaging element shown in FIG. 5 has a configuration in which a light incident preventing member 16 is added to the imaging element shown in FIG. The light incident preventing member 16 is for preventing light incident on the photoelectric conversion film 5 of the pixel portion from entering the photoelectric conversion film 5 of the adjacent pixel portion. The light incident preventing member 16 is provided between the photoelectric conversion film 5 of an arbitrary pixel portion and the photoelectric conversion film 5 of the pixel portion adjacent to the pixel portion. The light incident preventing member 16 can use an absorbing material that absorbs incident light (for example, tungsten) or a reflective material that reflects incident light (for example, aluminum or silver). With such a structure, light incident on the pixel portion can be prevented from entering the adjacent pixel portion, so that the resolution can be improved.

  In addition, although the example which adds the light-incident prevention member 16 to the structure shown in FIG.4 (d) was shown here, the structure shown in each of FIG.1, FIG.2, FIG.4 (a)-(c) is shown. A configuration in which the light incident preventing member 16 is added is also possible. Further, it is preferable to use a reflective material as the material of the light incident preventing member 16. This is because by using a reflective material, the light incident on the light incident preventing member 16 is reflected and re-enters the photoelectric conversion film 5, and as a result, the amount of charge obtained from the photoelectric conversion film 5 can be increased. Because. In addition, the light incident preventing member 16 is particularly effective in a configuration in which the microlens 14 is not provided. This is because when the microlens 14 is provided, the probability that incident light goes to the adjacent pixel portion is low, but when the microlens 14 is not provided, this probability is very high.

The figure which shows schematic structure of 1 pixel part of the image pick-up element which is 1st embodiment of this invention. The figure which shows schematic structure of 1 pixel part of the image pick-up element which is 2nd embodiment of this invention. The figure which shows the modification of the lower electrode of the image pick-up element of 2nd embodiment. The figure which shows schematic structure of 1 pixel part of the image pick-up element which is 3rd embodiment of this invention. The figure which shows schematic structure of 1 pixel part of the image pick-up element which is 4th embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor substrate 3 Photoelectric conversion part 4 on substrate Substrate electrode 5 Photoelectric conversion film 6 Upper electrode 7 Photoelectric conversion part K in board | substrate Opening part 12 Conductive material 13 Optical waveguide 14 Microlens 15 Inner lens 16 Light incidence prevention member

Claims (8)

A photoelectric conversion part on a substrate including a lower electrode formed above a semiconductor substrate, an upper electrode formed above the lower electrode, and a photoelectric conversion film sandwiched between the lower electrode and the upper electrode, and the photoelectric conversion on the substrate An imaging device having a plurality of pixel portions on the same plane including an in-substrate photoelectric conversion portion formed inside the semiconductor substrate below the portion,
The upper electrode is a transparent electrode transparent to incident light incident from above the upper electrode,
The imaging device in which the lower electrode includes a reflection part that reflects the incident light and a transmission part that transmits the incident light. The imaging device according to claim 1,
The lower electrode is composed of a conductive reflective material film that reflects the incident light,
The lower electrode has an opening formed in the reflective material film;
An imaging device in which the reflective portion is formed by the reflective material film and the transmissive portion is formed by the opening. The imaging device according to claim 2,
An imaging device in which a conductive material transparent to the incident light is embedded in the opening. The imaging device according to any one of claims 1 to 3,
An imaging device in which the transmissive part is formed immediately above the in-substrate photoelectric conversion part. The image sensor according to any one of claims 1 to 4,
An image sensor in which the pixel unit includes an optical system for condensing light transmitted through the transmission unit on the in-substrate photoelectric conversion unit between the on-substrate photoelectric conversion unit and the semiconductor substrate. The imaging device according to any one of claims 1 to 5,
The imaging device, wherein the pixel unit includes a microlens for concentrating incident light on the transmission unit above the photoelectric conversion unit on the substrate. The imaging device according to any one of claims 1 to 6,
Light transmitted through the photoelectric conversion film of the arbitrary photoelectric conversion unit on the substrate between the photoelectric conversion film of the arbitrary photoelectric conversion unit on the substrate and the photoelectric conversion film of the adjacent photoelectric conversion unit on the substrate An image pickup device comprising a light incident preventing member that prevents the light from entering the photoelectric conversion film of the photoelectric conversion unit on the adjacent substrate. The imaging device according to claim 7,
An image sensor in which the light incident preventing member is made of a reflective material that reflects the incident light.

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