WO2022219987A1 - 撮像装置 - Google Patents
撮像装置 Download PDFInfo
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- WO2022219987A1 WO2022219987A1 PCT/JP2022/011258 JP2022011258W WO2022219987A1 WO 2022219987 A1 WO2022219987 A1 WO 2022219987A1 JP 2022011258 W JP2022011258 W JP 2022011258W WO 2022219987 A1 WO2022219987 A1 WO 2022219987A1
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- photoelectric conversion
- plug
- pixel electrode
- imaging device
- insulating layer
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Classifications
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- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K39/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic radiation-sensitive element covered by group H10K30/00
- H10K39/30—Devices controlled by radiation
- H10K39/32—Organic image sensors
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
- H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
- H01L27/144—Devices controlled by radiation
- H01L27/146—Imager structures
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N25/00—Circuitry of solid-state image sensors [SSIS]; Control thereof
- H04N25/70—SSIS architectures; Circuits associated therewith
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K30/00—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation
- H10K30/50—Photovoltaic [PV] devices
- H10K30/57—Photovoltaic [PV] devices comprising multiple junctions, e.g. tandem PV cells
-
- H—ELECTRICITY
- H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
- H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
- H10K39/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic radiation-sensitive element covered by group H10K30/00
- H10K39/30—Devices controlled by radiation
- H10K39/38—Interconnections, e.g. terminals
Definitions
- the present disclosure relates to imaging devices.
- An image sensor includes a plurality of pixels arranged one-dimensionally or two-dimensionally, including a photodetector element that generates an electrical signal according to the amount of incident light.
- a stacked image sensor is an image sensor having, as a pixel, a photodetector having a structure in which a photoelectric conversion film is stacked above a substrate.
- Patent Document 1 discloses a stacked image sensor.
- Patent Document 2 discloses a stacked image sensor in which a plurality of photoelectric conversion films are stacked.
- the present disclosure provides a high-performance imaging device.
- An imaging device includes a semiconductor substrate, a first pixel electrode, a first counter electrode facing the first pixel electrode, and a a first photoelectric conversion section located above the semiconductor substrate and configured to convert light in a first wavelength band into a first charge; and located above the first photoelectric conversion section, a second photoelectric conversion unit that converts light in a second wavelength region into a second charge; a plug penetrating through the first photoelectric conversion layer and connected to the second photoelectric conversion unit; and the first photoelectric conversion layer. an insulating layer positioned between the plug and covering side surfaces of the plug. The insulating layer has a tapered shape that tapers upward.
- FIG. 1 is a schematic diagram showing a circuit configuration of an imaging device according to an embodiment.
- FIG. 2 is a cross-sectional view schematically showing a cross-sectional structure of a pixel of the imaging device according to the embodiment.
- FIG. 3 is a plan view showing an electrode layout of pixels of the imaging device according to the embodiment. 4 is a cross-sectional view of a photoelectric conversion portion of a pixel taken along line IV-IV of FIG. 3.
- FIG. FIG. 5A is a cross-sectional view showing one step of the method for manufacturing the imaging device according to the embodiment.
- FIG. 5B is a cross-sectional view showing one step of the method for manufacturing the imaging device according to the embodiment.
- FIG. 5C is a cross-sectional view showing one step of the method for manufacturing the imaging device according to the embodiment.
- FIG. 5D is a cross-sectional view showing one step of the method for manufacturing the imaging device according to the embodiment.
- 5E is a cross-sectional view showing one step of the method for manufacturing the imaging device according to the embodiment.
- FIG. 5F is a cross-sectional view showing one step of the method for manufacturing the imaging device according to the embodiment.
- 5G is a cross-sectional view showing one step of the method for manufacturing the imaging device according to the embodiment.
- FIG. 5H is a cross-sectional view showing one step of the method for manufacturing the imaging device according to the embodiment.
- FIG. 5I is a cross-sectional view showing one step of the method for manufacturing the imaging device according to the embodiment.
- 6 is a cross-sectional view showing a plug penetrating the photoelectric conversion layer of the imaging device according to Modification 1.
- FIG. 7 is a cross-sectional view showing a plug penetrating the photoelectric conversion layer of the imaging device according to Modification 2.
- FIG. 8 is a cross-sectional view showing a plug penetrating the photoelectric conversion layer of the imaging device according to Modification 3.
- FIG. 9 is a cross-sectional view showing a plug passing through a photoelectric conversion layer of an imaging device according to Modification 4.
- Etching back with oxygen plasma or polishing with CMP can be considered as processing examples for removing the remaining coating film.
- CMP Chemical Mechanical Polishing
- the performance of the photoelectric conversion film may deteriorate due to the exposure of the photoelectric conversion film to oxygen.
- polishing by CMP there is a concern that the performance of the photoelectric conversion film may deteriorate due to mechanical damage to the film interface due to polishing stress.
- the conventional technology may cause performance deterioration of the photoelectric conversion film, and there is a problem that it is difficult to realize a high-performance imaging device.
- an imaging device includes a semiconductor substrate, a first photoelectric conversion unit, a second photoelectric conversion unit, a plug, and an insulating layer.
- the first photoelectric conversion unit is located above the semiconductor substrate and converts light in a first wavelength band into first charges.
- the second photoelectric conversion unit is positioned above the first photoelectric conversion unit and converts light in a second wavelength band into second charges.
- the first photoelectric conversion section includes a first pixel electrode, a first counter electrode facing the first pixel electrode, and a first photoelectric conversion layer positioned between the first pixel electrode and the first counter electrode. and including.
- the plug penetrates the first photoelectric conversion layer and is connected to the second photoelectric conversion section.
- the insulating layer is positioned between the first photoelectric conversion layer and the plug and covers side surfaces of the plug.
- the insulating layer has a tapered shape that tapers upward. Further, for example, the first photoelectric conversion layer may contain an organic substance.
- the insulating layer covering the side surface of the plug has an upwardly tapered shape
- the flat portion of the upper surface of the plug and the insulating layer has a relatively small area. Therefore, there is little risk of the coating film remaining on the flat portion.
- the centrifugal force generated during spin coating and the reflow during drying of the coating may cause can be expected to slide down.
- the first photoelectric conversion layer with a flat upper surface without performing additional processing for removing the coating film on the upper surface of the plug and the insulating layer. Specifically, etching for forming an opening in the first photoelectric conversion layer, or polishing or etching back for flattening the first photoelectric conversion layer may not be performed. For this reason, deterioration of the performance of the first photoelectric conversion layer is less likely to occur, so a high-performance imaging device can be realized.
- the second photoelectric conversion unit includes a second pixel electrode, a second counter electrode positioned above the second pixel electrode, and a portion between the second pixel electrode and the second counter electrode. and a second photoelectric conversion layer, wherein the plug may be connected to the second pixel electrode.
- each of the first counter electrode, the second pixel electrode, and the second counter electrode may have translucency with respect to light in the first wavelength range.
- the imaging device further includes a charge accumulation region that is located within the semiconductor substrate and that accumulates the second charge, and the second photoelectric conversion unit receives the charge through the plug. , may be connected to the charge storage region.
- the signal charges generated in the second photoelectric conversion layer can be temporarily accumulated, and the accumulated signal charges can be read and processed at desired timing.
- the top surface of the plug may be located above the top surface of the first photoelectric conversion layer.
- the imaging device may further include a via connected to the lower end of the plug, and the width of the plug may be shorter than the width of the via.
- An imaging device includes a semiconductor substrate, a first photoelectric conversion section, a second photoelectric conversion section, and a plug.
- the first photoelectric conversion unit is located above the semiconductor substrate and converts light in a first wavelength band into first charges.
- the second photoelectric conversion unit is positioned above the first photoelectric conversion unit and converts light in a second wavelength band into second charges.
- the first photoelectric conversion section includes a first pixel electrode, a first counter electrode facing the first pixel electrode, and a first photoelectric conversion layer positioned between the first pixel electrode and the first counter electrode. and including.
- the plug penetrates the first photoelectric conversion layer and is connected to the second photoelectric conversion section.
- the plug has a tapered shape that tapers upward.
- each figure is a schematic diagram and is not necessarily strictly illustrated. Therefore, for example, scales and the like do not necessarily match in each drawing. Moreover, in each figure, substantially the same configurations are denoted by the same reference numerals, and overlapping descriptions are omitted or simplified.
- 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 structure. It is used as a term defined by a relative positional relationship. In other words, in actual use, the term “above” in this specification does not necessarily mean vertically upward, but may mean vertically downward, horizontally, or diagonally with respect to the vertical or horizontal direction. It is not limited.
- the terms “above” and “below” are used not only when two components are spaced apart from each other and there is another component between the two components, It also applies when two components are placed in close contact with each other so that the two components are in contact.
- the x-axis, y-axis and z-axis indicate three axes of a three-dimensional orthogonal coordinate system.
- the x-axis and the y-axis are parallel to the main surface of the semiconductor substrate and correspond to two directions perpendicular to each other.
- the z-axis coincides with the direction perpendicular to the main surface of the semiconductor substrate.
- the direction perpendicular to the main surface of the semiconductor substrate is also referred to as the thickness direction or lamination direction.
- plane view means viewing the principal surface of the semiconductor substrate from the front, that is, viewing from a direction perpendicular to the principal surface of the semiconductor substrate.
- FIG. 1 is a schematic diagram showing the circuit configuration of an imaging device 100 according to this embodiment. As shown in FIG. 1, the imaging device 100 includes multiple pixels 110 and a peripheral circuit 120 .
- a plurality of pixels 110 are arranged two-dimensionally, that is, in row and column directions on a semiconductor substrate to form a pixel region.
- the plurality of pixels 110 may be arranged in a line. That is, the imaging device 100 may be a line image sensor.
- the terms row direction and column direction refer to directions in which rows and columns extend, respectively. Specifically, the vertical direction in the drawings is the column direction, and the horizontal direction is the row direction.
- Each pixel 110 includes multiple sub-pixels 111 and 112 .
- Each of the sub-pixels 111 and 112 receives light in a predetermined wavelength range and generates an electrical signal according to the intensity of the received light.
- sub-pixels 111 and 112 each include a photoelectric conversion portion 50 or 60 and a charge detection circuit 25 .
- the photoelectric conversion unit 50 includes pixel electrodes 51 , photoelectric conversion layers 52 and transparent electrodes 53 .
- the photoelectric conversion unit 60 includes pixel electrodes 61 , photoelectric conversion layers 62 and transparent electrodes 63 . A specific configuration of the photoelectric conversion units 50 and 60 will be described later.
- Charge detection circuit 25 includes amplification transistor 11 , reset transistor 12 , and address transistor 13 .
- the imaging device 100 has voltage control elements for applying a predetermined voltage to the transparent electrodes 53 and 63 .
- Voltage control elements include, for example, a voltage control circuit, a voltage generation circuit such as a constant voltage source, and a voltage reference line such as a ground line.
- the voltage applied by the voltage control element is called the control voltage.
- the imaging device 100 includes a voltage control circuit 30 as a voltage control element.
- the voltage control circuit 30 may generate a constant control voltage, or may generate a plurality of control voltages with different values. For example, the voltage control circuit 30 may generate control voltages having two or more different values, or may generate control voltages that vary continuously within a predetermined range.
- the voltage control circuit 30 determines the value of the control voltage to be generated based on the command of the operator who operates the image capturing device 100 or the command of another control unit provided in the image capturing device 100, and determines the control voltage of the determined value. to generate
- the voltage control circuit 30 is provided outside the photosensitive area as part of the peripheral circuit 120 . Note that the photosensitive area is substantially the same as the pixel area.
- the voltage control circuit 30 applies a control voltage via the counter electrode signal line 16 to the transparent electrodes 53 or 63 of the pixels 110 arranged in the row direction. Thereby, the voltage control circuit 30 changes the voltage between the pixel electrode 51 and the transparent electrode 53 or the voltage between the pixel electrode 61 and the transparent electrode 63 to change the spectral sensitivity characteristic of the photoelectric conversion section 50 or 60. switch.
- the pixel electrode 61 is set to a potential higher than that of the transparent electrode 63 so that the photoelectric conversion unit 60 is irradiated with light and electrons are accumulated in the pixel electrode 61 as signal charges. At this time, since the moving direction of electrons is opposite to the moving direction of holes, a current flows from the pixel electrode 61 to the transparent electrode 63 . Further, the pixel electrode 61 is set to a potential lower than that of the transparent electrode 63 so that the photoelectric conversion unit 60 is irradiated with light and holes are accumulated in the pixel electrode 61 as signal charges. At this time, current flows from the transparent electrode 63 toward the pixel electrode 61 .
- the photoelectric conversion unit 50 is similar to the photoelectric conversion unit 60.
- the configuration of the charge detection circuit 25 connected to the photoelectric conversion section 50 is the same as the configuration of the charge detection circuit 25 connected to the photoelectric conversion section 60 .
- the following description focuses on the photoelectric conversion unit 60 and the charge detection circuit 25 connected to the photoelectric conversion unit 60, that is, the circuit configuration of the sub-pixel 112. FIG.
- the pixel electrode 61 is connected to the gate electrode of the amplification transistor 11, and the signal charges collected by the pixel electrode 61 are stored in the charge storage node 24 located between the pixel electrode 61 and the gate electrode of the amplification transistor 11. .
- Charge storage node 24 is an example of a charge storage region.
- the signal charges are holes.
- the signal charges may be electrons.
- the signal charge accumulated in the charge accumulation node 24 is applied to the gate electrode of the amplification transistor 11 as a voltage corresponding to the amount of signal charge.
- the amplification transistor 11 is included in the charge detection circuit 25 and amplifies the voltage applied to the gate electrode.
- the address transistor 13 selectively reads out the amplified voltage as the signal voltage. Address transistor 13 is also referred to as a row select transistor.
- the reset transistor 12 has one of its source electrode and drain electrode connected to the pixel electrode 61 and resets the signal charge accumulated in the charge accumulation node 24 . In other words, the reset transistor 12 resets the potentials of the gate electrode of the amplification transistor 11 and the pixel electrode 61 .
- the imaging device 100 includes a power supply line 21, a vertical signal line 17, an address signal line 26, and a reset signal line 27 in order to selectively perform the above-described operations in a plurality of sub-pixels 111 or 112. These wirings and signal lines are connected to sub-pixels 111 and 112, respectively.
- the power wiring 21 is connected to one of the source electrode and the drain electrode of the amplification transistor 11 .
- the vertical signal line 17 is connected to the other of the source electrode and the drain electrode of the address transistor 13 , ie, the one that is not connected to the amplification transistor 11 .
- the address signal line 26 is connected to the gate electrode of the address transistor 13 .
- the reset signal line 27 is connected to the gate electrode of the reset transistor 12 .
- the peripheral circuit 120 includes a vertical scanning circuit 15, a horizontal signal readout circuit 20, a plurality of column signal processing circuits 19, a plurality of load circuits 18, a plurality of differential amplifiers 22, and a voltage control circuit 30.
- the vertical scanning circuit 15 is also called a row scanning circuit.
- the horizontal signal readout circuit 20 is also called a column scanning circuit.
- the column signal processing circuit 19 is also called a row signal storage circuit.
- Differential amplifier 22 is also referred to as a feedback amplifier.
- the vertical scanning circuit 15 is connected to the address signal line 26 and the reset signal line 27, selects a plurality of sub-pixels 111 or 112 arranged in each row by row, reads out the signal voltage, and scans the pixel electrode 51 or 61. reset the potential of A power supply line 21 supplies a predetermined power supply voltage to each of the sub-pixels 111 and 112 .
- the horizontal signal readout circuit 20 is electrically connected to a plurality of column signal processing circuits 19 .
- the column signal processing circuit 19 is electrically connected to the sub-pixels 111 and 112 arranged in each column via vertical signal lines 17 corresponding to each column.
- a load circuit 18 is electrically connected to each vertical signal line 17 .
- the load circuit 18 and the amplification transistor 11 form a source follower circuit.
- a plurality of differential amplifiers 22 are provided corresponding to each column.
- a negative input terminal of the differential amplifier 22 is connected to the corresponding vertical signal line 17 .
- the output terminal of the differential amplifier 22 is connected to the sub-pixel 111 or 112 via the feedback line 23 corresponding to each column.
- the vertical scanning circuit 15 applies a row selection signal for controlling ON/OFF of the address transistor 13 to the gate electrode of the address transistor 13 through the address signal line 26 . This scans and selects the row to be read. A signal voltage is read out to the vertical signal line 17 from the sub-pixel 111 or 112 in the selected row. Also, the vertical scanning circuit 15 applies a reset signal for controlling ON/OFF of the reset transistor 12 to the gate electrode of the reset transistor 12 via the reset signal line 27 . This selects the row of the sub-pixels 111 or 112 to be reset. The vertical signal line 17 transmits the signal voltage read from the sub-pixel 111 or 112 selected by the vertical scanning circuit 15 to the column signal processing circuit 19 .
- the column signal processing circuit 19 performs noise suppression signal processing typified by correlated double sampling and analog-digital conversion (AD conversion). Specifically, the column signal processing circuit 19 includes a sample hold circuit.
- the sample-and-hold circuit includes capacitors, transistors, and the like. The sample hold circuit samples the signal voltage read out via the vertical signal line 17 and temporarily holds it. A digital value corresponding to the held voltage value is read out to the horizontal signal readout circuit 20 .
- the horizontal signal readout circuit 20 sequentially reads signals from the plurality of column signal processing circuits 19 to the horizontal common signal line 28 .
- the differential amplifier 22 is connected via a feedback line 23 to the other of the drain electrode and the source of the reset transistor 12, which is not connected to the pixel electrode 51 or 61. Therefore, differential amplifier 22 receives the output value of address transistor 13 at its negative input terminal when address transistor 13 and reset transistor 12 are in a conducting state.
- the differential amplifier 22 performs a feedback operation so that the gate potential of the amplification transistor 11 becomes a predetermined feedback voltage. At this time, the output voltage value of the differential amplifier 22 is 0V or a positive voltage near 0V. Feedback voltage means the output voltage of the differential amplifier 22 .
- FIG. 2 is a cross-sectional view schematically showing the cross section of the device structure of the pixel 110 of the imaging device 100 according to this embodiment.
- pixel 110 includes semiconductor substrate 31 , charge detection circuit 25 (not shown), and photoelectric conversion units 50 and 60 .
- the semiconductor substrate 31 is, for example, a p-type silicon substrate.
- the charge detection circuit 25 detects signal charge captured by the pixel electrode 51 or 61 and outputs a signal voltage.
- the charge detection circuit 25 includes an amplification transistor 11 , a reset transistor 12 and an address transistor 13 , and is at least partially formed on a semiconductor substrate 31 .
- Each of the amplification transistor 11 , the reset transistor 12 and the address transistor 13 is an example of an electric element at least partially formed on the semiconductor substrate 31 .
- Each of the amplification transistor 11, reset transistor 12 and address transistor 13 is, for example, a MOSFET (Metal Oxide Semiconductor Field Effect Transistor).
- MOSFET Metal Oxide Semiconductor Field Effect Transistor
- each of the amplification transistor 11, the reset transistor 12 and the address transistor 13 is an n-channel MOSFET, but may be a p-channel MOSFET.
- the amplification transistor 11 has n-type impurity regions 41C and 41D, a gate insulating layer 38B, and a gate electrode 39B.
- N-type impurity regions 41C and 41D are formed in semiconductor substrate 31 and function as drains and sources, respectively.
- a gate insulating layer 38B is located on the semiconductor substrate 31 .
- Gate electrode 39B is located on gate insulating layer 38B.
- the reset transistor 12 has n-type impurity regions 41A and 41B, a gate insulating layer 38A, and a gate electrode 39A.
- N-type impurity regions 41A and 41B are formed in semiconductor substrate 31 and function as drains and sources, respectively.
- a gate insulating layer 38A is located on the semiconductor substrate 31 .
- Gate electrode 39A is located on gate insulating layer 38A.
- the address transistor 13 has n-type impurity regions 41D and 41E, a gate insulating layer 38C, and a gate electrode 39C.
- N-type impurity regions 41D and 41E are formed in semiconductor substrate 31 and function as drains and sources, respectively.
- a gate insulating layer 38C is located on the semiconductor substrate 31 .
- a gate electrode 39C is located on the gate insulating layer 38C.
- the gate insulating layers 38A, 38B and 38C are formed using an insulating material.
- the gate insulating layers 38A, 38B and 38C have a single layer structure of silicon oxide film or silicon nitride film, or a laminated structure of these.
- the gate electrodes 39A, 39B and 39C are each formed using a conductive material.
- the gate electrodes 39A, 39B and 39C are formed using polysilicon to which conductivity is imparted by adding impurities.
- gate electrodes 39A, 39B and 39C may be formed using a metal material such as copper.
- the n-type impurity regions 41A, 41B, 41C, 41D and 41E are formed by doping the semiconductor substrate 31 with n-type impurities such as phosphorus (P) by ion implantation or the like.
- n-type impurities such as phosphorus (P) by ion implantation or the like.
- the n-type impurity region 41D is shared by the amplifying transistor 11 and the address transistor 13.
- the amplification transistor 11 and the address transistor 13 are connected in series.
- the n-type impurity region 41D may be separated into two n-type impurity regions. These two n-type impurity regions may be electrically connected via a wiring layer.
- element isolation regions 42 are provided between the adjacent pixels 110 and between the amplification transistor 11 and the reset transistor 12 .
- the element isolation region 42 provides electrical isolation between adjacent pixels 110 .
- the provision of the element isolation region 42 suppresses leakage of the signal charges accumulated in the charge accumulation node 24 .
- the element isolation region 42 is formed by, for example, doping the semiconductor substrate 31 with a p-type impurity at a high concentration.
- a multilayer wiring structure is provided on the upper surface of the semiconductor substrate 31 .
- a multilayer wiring structure includes a plurality of interlayer insulating layers, one or more wiring layers, one or more vias and one or more contact plugs.
- interlayer insulating layers 43A, 43B and 43C are laminated in this order on the upper surface of the semiconductor substrate 31 .
- the interlayer insulating layers 43A, 43B, and 43C are, for example, TEOS (tetraethyl orthosilicate) films, but may be single-layer or laminated films such as silicon oxide films, silicon nitride films, silicon oxynitride films, and aluminum oxide films. .
- the interlayer insulating layers 43A, 43B and 43C may be formed using the same insulating material, or may be formed using different insulating materials.
- Wiring 46A and via 47A are embedded in the interlayer insulating layer 43A.
- Wirings 46B and 48B and vias 47B are embedded in the interlayer insulating layer 43B.
- Wirings 46C and 48C, vias 47C, pixel electrodes 51 and conductive films 71 are embedded in the interlayer insulating layer 43C.
- the upper surface of the interlayer insulating layer 43C is flat and parallel to the upper surface of the semiconductor substrate 31, for example.
- the contact plug 45A is connected to the n-type impurity region 41B of the reset transistor 12.
- Contact plug 45B is connected to gate electrode 39B of amplifying transistor 11 .
- the wiring 46A connects the contact plug 45A and the contact plug 45B.
- the n-type impurity region 41B of the reset transistor 12 is electrically connected to the gate electrode 39B of the amplification transistor 11 .
- the wiring 46A is connected to the pixel electrode 61 via vias 47A, 47B and 47C, the wirings 46B and 46C, the conductive film 71 and the plug 70.
- the n-type impurity region 41B, the gate electrode 39B, the contact plugs 45A and 45B, the wirings 46A, 46B and 46C, the vias 47A, 47B and 47C, the conductive film 71, the plug 70, and the pixel electrode 61 are connected to the charge storage node 24. configure.
- vias and wiring connected to the pixel electrodes 51 are also embedded in the interlayer insulating layers 43A, 43B or 43C.
- the amplification transistor 11 , reset transistor 12 and address transistor 13 included in the sub-pixel 111 are also formed on the semiconductor substrate 31 .
- the photoelectric conversion units 50 and 60 are provided above the semiconductor substrate 31 respectively.
- the photoelectric conversion units 50 and 60 are stacked in this order above the semiconductor substrate 31 .
- the photoelectric conversion unit 50 is an example of a first photoelectric conversion unit that converts light in the first wavelength band into first charges.
- the photoelectric conversion unit 50 is provided on the interlayer insulating layer 43C.
- the photoelectric conversion unit 60 is an example of a second photoelectric conversion unit that is positioned above the photoelectric conversion unit 50 and converts light in the second wavelength band into second charges.
- the photoelectric conversion section 60 is provided above the photoelectric conversion section 50 with an insulating layer 81 interposed therebetween.
- the first wavelength band and the second wavelength band are wavelength bands different from each other.
- the first wavelength band and the second wavelength band are different wavelength bands that do not overlap at all, but may partially overlap.
- the light in the first wavelength band is near-infrared light.
- the light in the second wavelength band is visible light.
- An insulating layer 82 is provided above the photoelectric conversion section 60 .
- the insulating layer 82 covers at least part of the upper surface of the transparent electrode 63 .
- the insulating layer 82 is formed using an insulating material.
- the insulating layer 82 is made of silicon oxide (SiO 2 ), silicon nitride (SiN), silicon oxynitride (SiON), aluminum oxide (AlO), organic or inorganic polymer materials, or the like.
- the insulating layer 82 is transparent to, for example, light of wavelengths to be detected by the imaging device 100, specifically light of the first wavelength range and light of the second wavelength range.
- the insulating layer 82 functions as a protective film for the photoelectric conversion section 60 .
- the pixel 110 has a color filter 91 above the photoelectric conversion section 60 .
- pixel 110 comprises microlens 92 above color filter 91 . Note that the pixel 110 does not have to include the insulating layer 82 , the color filter 91 and the microlens 92 .
- FIG. 3 is a plan view showing the electrode layout of the pixels 110 of the imaging device 100 according to this embodiment.
- FIG. 4 is a schematic cross-sectional view of the photoelectric conversion units 50 and 60 of the pixel 110 along line IV-IV in FIG.
- the photoelectric conversion section 50 includes a pixel electrode 51, a photoelectric conversion layer 52, and a transparent electrode 53.
- the pixel electrode 51 is an example of a first pixel electrode.
- the pixel electrode 51 faces the transparent electrode 53 with the photoelectric conversion layer 52 interposed therebetween.
- a pixel electrode 51 is provided for each pixel 110 .
- one pixel electrode 51 is provided for one pixel 110 as shown in FIG. good too.
- the pixel electrode 51 is formed using, for example, a metal such as aluminum or copper, or a conductive material such as polysilicon doped with impurities to impart conductivity.
- the pixel electrode 51 is connected to a charge accumulation region (not shown) provided below. Specifically, as shown in FIG. 4, the bottom surface of the pixel electrode 51 is connected to a via 47D.
- the via 47D is electrically connected to an impurity region (also called floating diffusion) provided in the semiconductor substrate 31 via wiring, other vias, contact plugs, and the like (not shown). Note that the via 47D may be directly connected to the impurity region.
- the via 47D, the impurity region, and the like are each part of the charge storage region. As a result, charges generated by photoelectric conversion in the photoelectric conversion layer 52 are accumulated in the charge accumulation regions via the pixel electrodes 51 .
- the photoelectric conversion layer 52 is an example of a first photoelectric conversion layer.
- the photoelectric conversion layer 52 photoelectrically converts light incident from the transparent electrode 53 side, thereby generating signal charges corresponding to the intensity of the incident light. Specifically, the photoelectric conversion layer 52 receives near-infrared light and generates signal charges according to the intensity of the received near-infrared light.
- the photoelectric conversion layer 52 contains an organic matter.
- the photoelectric conversion layer 52 is composed of an organic semiconductor.
- Photoelectric conversion layer 52 may include one or more organic semiconductor layers.
- the photoelectric conversion layer 52 may include a photoelectric conversion layer that generates hole-electron pairs, a carrier transport layer that transports electrons or holes, a blocking layer that blocks carriers, and the like.
- Organic p-type semiconductors and organic n-type semiconductors of known materials can be used for these organic semiconductor layers.
- the photoelectric conversion layer 52 may be, for example, a mixed film of organic donor molecules and acceptor molecules, a mixed film of semiconducting carbon nanotubes and acceptor molecules, or a film containing quantum dots.
- the photoelectric conversion layer 52 may be formed using an inorganic material such as amorphous silicon.
- the photoelectric conversion layer 52 is positioned between the pixel electrode 51 and the transparent electrode 53 .
- the photoelectric conversion layer 52 is continuously formed over the plurality of pixels 110 .
- the photoelectric conversion layer 52 is formed in a single flat plate shape so as to cover most of the imaging region in plan view. Note that the photoelectric conversion layer 52 may be provided separately for each pixel 110 .
- the transparent electrode 53 is an example of a first counter electrode and is positioned above the pixel electrode 51 .
- the transparent electrode 53 has translucency with respect to light in the first wavelength band to be detected by the photoelectric conversion layer 52 .
- the transparent electrode 53 is transparent to light in the first wavelength band.
- transparent refers to a state in which the transmittance for light in a predetermined wavelength range is sufficiently high, for example, a state in which the transmittance is greater than 50%.
- the transparent electrode 53 is formed using a conductive material.
- the transparent electrode 53 is formed using a transparent conductive semiconductor oxide film such as indium tin oxide (ITO), aluminum-added zinc oxide (AZO), or gallium-added zinc oxide (GZO).
- ITO indium tin oxide
- AZO aluminum-added zinc oxide
- GZO gallium-added zinc oxide
- the transparent electrode 53 may be formed using another transparent conductive semiconductor, or may be formed using a metal thin film thin enough to transmit light in the first wavelength band.
- the transparent electrode 53 is formed continuously over a plurality of pixels 110 in the same manner as the photoelectric conversion layer 52 . Specifically, the transparent electrode 53 is formed in a single flat plate shape so as to cover most of the imaging region in plan view. The transparent electrode 53 continuously covers substantially the entire upper surface of the photoelectric conversion layer 52 .
- the photoelectric conversion section 60 includes a pixel electrode 61, a photoelectric conversion layer 62, and a transparent electrode 63.
- the pixel electrode 61 is an example of a second pixel electrode.
- the pixel electrode 61 faces the transparent electrode 63 with the photoelectric conversion layer 62 interposed therebetween.
- a pixel electrode 61 is provided for each pixel 110 .
- four pixel electrodes 61 are provided for one pixel 110, as shown in FIG. Note that the four pixel electrodes 61 may be one pixel electrode connected to each other.
- the photoelectric conversion layer 62 is an example of a second photoelectric conversion layer.
- the photoelectric conversion layer 62 photoelectrically converts light incident from the transparent electrode 63 side, thereby generating signal charges corresponding to the intensity of the incident light. Specifically, the photoelectric conversion layer 62 receives visible light and generates signal charges according to the intensity of the received visible light.
- the photoelectric conversion layer 62 contains an organic substance.
- the photoelectric conversion layer 62 is composed of an organic semiconductor.
- Photoelectric conversion layer 62 may include one or more organic semiconductor layers.
- the photoelectric conversion layer 62 may contain a carrier transport layer, a blocking layer, and the like.
- the photoelectric conversion layer 62 may be, for example, a mixed film of organic donor molecules and acceptor molecules, a mixed film of semiconducting carbon nanotubes and acceptor molecules, or a film containing quantum dots.
- the photoelectric conversion layer 62 may be formed using an inorganic material such as amorphous silicon.
- the photoelectric conversion layer 62 is positioned between the pixel electrode 61 and the transparent electrode 63 .
- the photoelectric conversion layer 62 is continuously formed over the plurality of pixels 110 .
- the photoelectric conversion layer 62 may be provided separately for each pixel 110 .
- the transparent electrode 63 is an example of a second counter electrode and is positioned above the pixel electrode 61 .
- the transparent electrode 63 has translucency with respect to the light in the second wavelength range to be detected by the photoelectric conversion layer 62 .
- the transparent electrode 63 is transparent to light in the second wavelength band.
- the transparent electrode 63 is formed using a conductive material.
- the transparent electrode 63 is formed using a transparent conductive semiconductor oxide film such as ITO, AZO, GZO.
- the transparent electrode 63 may be formed using another transparent conductive semiconductor, or may be formed using a metal thin film thin enough to transmit light.
- the photoelectric conversion section 60 is positioned on the incident side of the light in the first wavelength band received by the photoelectric conversion section 50 . Therefore, the pixel electrode 61, the photoelectric conversion layer 62, and the transparent electrode 63, which constitute the photoelectric conversion section 60, all transmit light in the first wavelength band. Specifically, the pixel electrode 61, the photoelectric conversion layer 62, and the transparent electrode 63 are all transparent to light in the first wavelength band.
- An insulating layer 81 is provided between the photoelectric conversion section 50 and the photoelectric conversion section 60 .
- the insulating layer 81 is provided to electrically insulate the photoelectric conversion units 50 and 60 from each other. Since the photoelectric conversion section 50 is arranged below the photoelectric conversion section 60 , the insulating layer 81 is also formed using a material that transmits light in the first wavelength band received by the photoelectric conversion section 50 . Specifically, the insulating layer 81 is formed using AlO, SiON, or the like.
- the pixel electrode 61 of the photoelectric conversion section 60 is connected to a conductive plug 70 penetrating through the photoelectric conversion layer 52 .
- the pixel electrode 61 is connected through a plug 70 to a conductive film 71 formed below the photoelectric conversion layer 52, and further to a charge storage region for storing charges generated during photoelectric conversion.
- pixel electrode 61 is connected to n-type impurity region 41B through plug 70, conductive film 71, via 47C, and the like.
- the n-type impurity region 41B is part of the charge storage region.
- the plug 70 is formed using a metal material such as Cu.
- the plug 70 is, for example, a columnar plug and has a height approximately equal to the thickness of the photoelectric conversion layer 52 .
- An insulating layer 80 for electrically insulating the photoelectric conversion layer 52 is provided around the plug 70 .
- the insulating layer 80 is located between the plug 70 and the photoelectric conversion layer 52 and covers the side surface 70 c of the plug 70 .
- the insulating layer 80 is formed using an insulating material such as TEOS, SiO2 or SiN.
- the insulating layer 80 has a tapered shape that tapers upward. Specifically, the shape of the insulating layer 80 is a truncated cone shape with a through hole provided in the center. As shown in FIGS. 3 and 4, a plug 70 is embedded in the central through hole.
- the insulating layer 80 has an upper surface 80a and a lower surface 80b. The area of the upper surface 80a is smaller than the area of the lower surface 80b. Specifically, in a plan view, the inner circumference of the upper surface 80 a and the inner circumference of the lower surface 80 b overlap each other and match the outer shape of the plug 70 . In addition, the outer circumference of the upper surface 80a is located inside the outer circumference of the lower surface 80b.
- the lower surface 80 b is larger than the conductive film 71 and prevents the conductive film 71 from contacting the photoelectric conversion layer 52 .
- the inclination angle of the outer surface 80c of the insulating layer 80 is constant.
- the angle of inclination is the angle formed between the outer side surface 80c and the xy plane in the xz cross section passing through the center of the plug 70 (that is, the cross section shown in FIG. 4).
- the xy plane is a plane parallel to the main surface of the semiconductor substrate 31 .
- the shape of the insulating layer 80 is not limited to a truncated cone shape with a through hole provided in the center.
- the outer surface 80c of the insulating layer 80 may be curved downward or convex upward. That is, the inclination of the outer side surface 80c of the insulating layer 80 may not be constant.
- the outer surface 80c of the insulating layer 80 may be formed stepwise.
- FIGS. 5A to 5I are cross-sectional views showing each step of the manufacturing method of the imaging device according to this embodiment.
- the charge detection circuit 25 is formed inside the semiconductor substrate 31 .
- the amplification transistor 11, the reset transistor 12, the address transistor 13, the element isolation region 42, and the like are formed using a known technique such as the CMOS process.
- FIG. 5A illustrates the uppermost interlayer insulating layer 43C, vias 47C and 47D provided inside the interlayer insulating layer 43C, the pixel electrode 51 and the conductive film 71.
- the illustration of the semiconductor substrate 31 and the like is omitted in FIGS. 5A to 5I.
- the interlayer insulating layer 43C is a TEOS film, for example, and is formed by a CVD (Chemical Vapor Deposition) method or the like. Contact holes are formed in the TEOS film by photolithography and etching, and vias 47C and 47D are formed by burying Cu therein. Further, a buried TiN electrode is formed as the conductive film 71 and the pixel electrode 51 on the upper layer of the TEOS film.
- CVD Chemical Vapor Deposition
- the TEOS film 80A is deposited over the entire surface, the portion corresponding to the lower portion of the pixel electrode 61 of the photoelectric conversion section 60, that is, the upper portion of the conductive film 71 is removed by etching. to form a via hole 70A. As a result, the upper surface of the conductive film 71 is exposed at the bottom of the via hole 70A.
- plugs 70 are formed by filling the via holes 70A with Cu.
- the embedding of Cu is performed using, for example, electrolytic plating. Therefore, although not shown, a seed layer used for plating and a barrier layer for preventing diffusion of Cu are formed on the bottom surface and side surfaces of the plug 70 made of Cu. Ti or Ta, for example, is used for the barrier layer.
- the TEOS film 80A except for the TEOS film 80A near the plug 70 is removed by dry etching, for example.
- etching conditions are controlled so that the width of the TEOS film covering the side surface 70c of the plug 70 increases from the top to the bottom of the plug 70 .
- the shape of the insulating layer 80 which is the remaining TEOS film, can be tapered upward.
- the etching gas is mixed with a gas that causes reaction products to adhere to the side walls of the etched portion.
- the shape of the insulating layer 80 formed by etching can be controlled.
- the shape of the insulating layer 80 can also be controlled by selecting a resist that serves as a protective material during etching.
- the insulating layer 80 having a tapered shape can be formed by using a resist having a characteristic that the end portion is easily inclined. That is, the outer side surface 80c of the insulating layer 80 is obliquely inclined.
- a photoelectric conversion material that will form the photoelectric conversion layer 52 is applied onto the interlayer insulating layer 43C by spin coating.
- the coating film formed by spin coating is less likely to run on the upper surfaces of the plugs 70 and the insulating layer 80 .
- the coating film on the plug 70 and the insulating layer 80 slides down to the surroundings via the oblique outer surface 80c of the insulating layer 80 . Therefore, as shown in FIG.
- the upper surface 70a of the plug 70, the upper surface 80a of the insulating layer 80, and the upper surface 52a of the photoelectric conversion layer 52 can be flush with each other.
- a step of optimizing various parameters such as the rotation speed of spin coating or the viscosity of the coating material may be performed separately so that the height of the coating film is the same as that of the plug 70 .
- an electrode material is deposited on the upper surface 52a of the photoelectric conversion layer 52, the upper surface 70a of the plug 70, and the upper surface 80a of the insulating layer 80.
- Film formation of the electrode material is performed, for example, by sputtering, vapor deposition, or the like.
- the electrode material on the upper surface 80a of the insulating layer 80 is removed by patterning the deposited electrode material. Thereby, the electrode material on the photoelectric conversion layer 52 and the electrode material on the plug 70 are separated.
- the electrode material above the photoelectric conversion layer 52 is the transparent electrode 53 of the photoelectric conversion section 50 .
- an insulating film is deposited on the entire surface, and only the insulating film above the plugs 70 is removed by etching.
- insulating layer 81 is formed so as to expose only the electrode material electrically connected to plug 70 .
- an electrode material is deposited on the upper surface of the insulating layer 81 and patterned into a predetermined shape by etching. Thereby, the pixel electrode 61 of the photoelectric conversion unit 60 is formed.
- a photoelectric conversion layer 62 is formed.
- the photoelectric conversion layer 62 is formed by, for example, spin coating, similarly to the photoelectric conversion layer 52 .
- a transparent electrode 63 is formed on the photoelectric conversion layer 62, and an insulating layer 82 is formed on the upper surface thereof as a protective film. Thereby, the laminated structure of the photoelectric conversion units 50 and 60 shown in FIG. 4 is formed.
- the imaging device 100 shown in FIG. 2 is manufactured by forming the color filter 91 and the microlens 92 as necessary.
- FIG. 6 is a cross-sectional view showing a plug 170 penetrating through the photoelectric conversion layer 52 of the imaging device according to Modification 1.
- top surface 170 a of plug 170 and top surface 180 a of insulating layer 180 are located above top surface 52 a of photoelectric conversion layer 52 . That is, the top surface 170a of the plug 170 and the top surface 180a of the insulating layer 180 do not have to be flush with the top surface 52a of the photoelectric conversion layer 52 .
- FIG. 6 shows an example in which the upper surface 170a of the plug 170 and the upper surface 180a of the insulating layer 180 are flush with each other, the upper surface 170a and the upper surface 180a may have a step.
- the top surface 170 a of the plug 170 may be positioned above the top surface 180 a of the insulating layer 180 .
- FIG. 7 is a cross-sectional view showing a plug 270 penetrating through the photoelectric conversion layer 52 of the imaging device according to Modification 2.
- width d1 of plug 270 is shorter than width d2 of via 47C to which plug 270 is connected.
- Widths d1 and d2 are the maximum widths of plug 270 or via 47C, respectively. If the shape of the plug 270 is cylindrical, the width d1 is the diameter of the bottom surface. For example, in plan view, the entire plug 270 is positioned inside the contour of the via 47C.
- the areas of the upper surface 70a of the plug 270 and the upper surface 80a of the insulating layer 80 become smaller. This makes it difficult for the coating film to remain on the upper surface 70a of the plug 270 and the upper surface 80a of the insulating layer 80, so that the photoelectric conversion layer 52 can be easily planarized.
- FIG. 8 is a cross-sectional view showing a plug 370 penetrating through the photoelectric conversion layer 52 of the imaging device according to Modification 3.
- the plug 370 has an upwardly tapered shape. That is, the side surface 370c of the plug 370 is inclined with respect to the xy plane.
- the shape of the plug 370 is, for example, an upwardly tapering truncated cone or pyramid.
- the width of the insulating layer 380 is constant. That is, the outer side surface 80c of the insulating layer 380 and the side surface 370c of the plug 370 are parallel in a cross section perpendicular to the xy plane. Since the plug 370 has such a tapered shape, the insulating layer 380 covering the side surface 370c of the plug 370 may also have an upwardly tapered shape. Even in this case, it is possible to obtain the same effects as in the above-described embodiment.
- the width of the insulating layer 380 may not be constant.
- the thickness of the insulating layer 380 may be thicker at the lower end than at the upper end.
- the tapered shape of the insulating layer 380 has a smaller inclination angle than the tapered shape of the plug 370 .
- the thickness of the insulating layer 380 may be thinner at the lower end than at the upper end as long as the outer surface 80c of the insulating layer 380 tapers upward.
- FIG. 9 is a cross-sectional view showing a plug 470 penetrating through the photoelectric conversion layer 52 of the imaging device according to Modification 4.
- the plug 470 has a tapered shape that tapers downward, that is, a reverse tapered shape. That is, the side surface 470c of the plug 470 is inclined opposite to the side surface 370c in FIG. 8 with respect to the z-axis direction.
- the shape of the plug 470 is, for example, a downwardly tapering truncated cone or pyramid.
- the width of the insulating layer 480 is greater at the lower end than at the upper end.
- the insulating layer 480 is provided to fill the space between the plug 470 and the conductive film 71, and has an upwardly tapering outer side surface 80c. Even in this case, it is possible to obtain the same effects as in the above-described embodiment.
- the shape of the plug and the insulating layer according to each modification can be formed by appropriately adjusting the etching conditions, the film forming conditions, and the like.
- the photoelectric conversion unit 50 located on the semiconductor substrate 31 side receives near-infrared light
- the photoelectric conversion unit 60 located above receives visible light.
- the photoelectric conversion unit 60 may receive near-infrared light
- the photoelectric conversion unit 50 may receive visible light.
- the photoelectric conversion units 50 and 60 may receive light in mutually different wavelength ranges, such as mutually different visible light.
- the photoelectric conversion units 50 and 60 may receive light in the same wavelength range. That is, the first wavelength band and the second wavelength band may completely match.
- the range in which light in the same wavelength range can be received is widened, and the dynamic range of the imaging device can be widened.
- three or more photoelectric conversion units may be stacked.
- the wavelength regions of light detected by each of the three photoelectric conversion units may at least partially overlap each other, or may be completely different.
- the arrangement of the pixel electrode 61 and the transparent electrode 63 may be reversed. That is, the transparent electrode 63, the photoelectric conversion layer 62, and the pixel electrode 61 may be arranged in this order from the photoelectric conversion section 50 side. In this case, the transparent electrode 53 of the photoelectric conversion section 50 and the transparent electrode 63 of the photoelectric conversion section 60 may be one common electrode. Also, the plug 70 and the insulating layer 80 may penetrate the photoelectric conversion layer 62 . In this case, the insulating layer 80 is tapered upward at a portion located between the plug 70 and the photoelectric conversion layer 52 and at a portion located between the plug 70 and the photoelectric conversion layer 62 . have a shape. That is, the insulating layer 80 has, for example, two frustoconical portions.
- the arrangement of the pixel electrode 51 and the transparent electrode 53 may be reversed. That is, the transparent electrode 53, the photoelectric conversion layer 52, and the pixel electrode 51 may be arranged in this order from the semiconductor substrate 31 side.
- the present disclosure can be used as a high-performance imaging device, such as a camera or rangefinder.
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Abstract
Description
特許文献2に開示された撮像装置のように、複数の光電変換膜が積層された構造では、下層の光電変換膜を貫通し、上層の光電変換膜に接続される縦配線を形成する必要がある。具体的には、光電変換膜を形成した後、光電変換膜に開口を形成し、形成した開口を埋めるように絶縁膜を形成する。さらに、絶縁膜の一部であって開口を埋める部分に縦配線用の開口を形成し、形成した開口に縦配線を形成している。
[1.撮像装置の回路構成]
まず、本実施の形態に係る撮像装置の回路構成について、図1を用いて概括的に説明する。
以下では、撮像装置100の画素110の詳細なデバイス構造について、図2を用いて説明する。図2は、本実施の形態に係る撮像装置100の画素110のデバイス構造の断面を模式的に示す断面図である。
以下では、図3および図4を用いて、本実施の形態に係る2つの光電変換部50および60の構造について説明する。
次に、図4に示される光電変換部の積層構造の製造方法について、図5Aから図5Iを用いて説明する。図5Aから図5Iは、本実施の形態に係る撮像装置の製造方法の各工程を示す断面図である。
続いて、実施の形態の変形例について説明する。
以上、1つまたは複数の態様に係る撮像装置について、実施の形態に基づいて説明したが、本開示は、これらの実施の形態に限定されるものではない。本開示の主旨を逸脱しない限り、当業者が思いつく各種変形を本実施の形態に施したもの、および、異なる実施の形態における構成要素を組み合わせて構築される形態も、本開示の範囲内に含まれる。
12 リセットトランジスタ
13 アドレストランジスタ
15 垂直走査回路
16 対向電極信号線
17 垂直信号線
18 負荷回路
19 カラム信号処理回路
20 水平信号読出し回路
21 電源配線
22 差動増幅器
23 フィードバック線
24 電荷蓄積ノード
25 電荷検出回路
26 アドレス信号線
27 リセット信号線
28 水平共通信号線
30 電圧制御回路
31 半導体基板
38A、38B、38C ゲート絶縁層
39A、39B、39C ゲート電極
41A、41B、41C、41D、41E n型不純物領域
42 素子分離領域
43A、43B、43C 層間絶縁層
45A、45B コンタクトプラグ
46A、46B、46C、48B、48C 配線
47A、47B、47C、47D ビア
50、60 光電変換部
51、61 画素電極
52、62 光電変換層
52a、70a、80a、170a、180a 上面
53、63 透明電極
70、170、270、370、470 プラグ
70A ビアホール
70c、370c、470c 側面
71 導電膜
80、81、82、180、380、480 絶縁層
80A TEOS膜
80b 下面
80c 外側面
91 カラーフィルター
92 マイクロレンズ
100 撮像装置
110 画素
111、112 サブ画素
120 周辺回路
Claims (8)
- 半導体基板と、
第1画素電極、前記第1画素電極に対向する第1対向電極、及び前記第1画素電極と前記第1対向電極との間に位置する第1光電変換層を含み、前記半導体基板の上方に位置し、第1波長域の光を第1電荷に変換する第1光電変換部と、
前記第1光電変換部の上方に位置し、第2波長域の光を第2電荷に変換する第2光電変換部と、
前記第1光電変換層を貫通し、前記第2光電変換部に接続されるプラグと、
前記第1光電変換層と前記プラグとの間に位置し、前記プラグの側面を覆う絶縁層と、を備え、
前記絶縁層は、上方に向かって先細るテーパ形状を有する、
撮像装置。 - 前記第1光電変換層は、有機物を含む、
請求項1に記載の撮像装置。 - 前記第2光電変換部は、
第2画素電極と、
前記第2画素電極の上方に位置する第2対向電極と、
前記第2画素電極と前記第2対向電極との間に位置する第2光電変換層と、を含み、
前記プラグは、前記第2画素電極に接続される、
請求項1または2に記載の撮像装置。 - 前記第1対向電極、前記第2画素電極および前記第2対向電極はそれぞれ、前記第1波長域の光に対して透光性を有する、
請求項3に記載の撮像装置。 - さらに、
前記半導体基板内に位置し、前記第2電荷を蓄積する電荷蓄積領域を備え、
前記第2光電変換部は、前記プラグを介して前記電荷蓄積領域に接続されている、
請求項1から4のいずれか1項に記載の撮像装置。 - 前記プラグの上面は、前記第1光電変換層の上面より上方に位置している、
請求項1から5のいずれか1項に記載の撮像装置。 - さらに、
前記プラグの下端に接続されたビアを備え、
前記プラグの幅は、前記ビアの幅より短い、
請求項1から6のいずれか1項に記載の撮像装置。 - 半導体基板と、
第1画素電極、前記第1画素電極に対向する第1対向電極、及び前記第1画素電極と前記第1対向電極との間に位置する第1光電変換層を含み、前記半導体基板の上方に位置し、第1波長域の光を第1電荷に変換する第1光電変換部と、
前記第1光電変換部の上方に位置し、第2波長域の光を第2電荷に変換する第2光電変換部と、
前記第1光電変換層を貫通し、前記第2光電変換部に接続されるプラグと、を備え、
前記プラグは、上方に向かって先細るテーパ形状を有する、
撮像装置。
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