JP2022163433A - Imaging element and imaging device - Google Patents

Abstract

SOLUTION: There is provided an imaging element including: a first substrate having a pixel portion in which a plurality of pixels each having a micro-lens and a photoelectric conversion portion is provided in a first direction and in a second direction intersecting the first direction; a second substrate having a processing circuit portion in which a plurality of processing circuits for processing pixel signals output from the pixels is provided in the first direction and the second direction; and a light shielding layer provided between the first substrate and the second substrate in an optical axis direction of the micro-lens and shielding light from the processing circuit portion. Furthermore, there may be provided an imaging device provided with the imaging element.SELECTED DRAWING: Figure 1

Description

The present invention relates to an imaging device and an imaging device.

2. Description of the Related Art An imaging device including a processing circuit such as an AD converter is known (for example, Patent Document 1). Conventionally, noise caused by light generated in the AD converter has been a problem.
Patent document 1 JP 2013-51674

In a first aspect of the present invention, an imaging device has a pixel portion in which a plurality of pixels each having a microlens and a photoelectric conversion portion are provided in a first direction and in a second direction intersecting the first direction. a first substrate; a second substrate having a processing circuit section in which a plurality of processing circuits for processing pixel signals output from pixels are provided in a first direction and a second direction; A light shielding layer provided between the first substrate and the second substrate for shielding light from the processing circuit section.

According to a second aspect of the present invention, there is provided an image pickup apparatus including the above image pickup device.

It should be noted that the above summary of the invention does not list all the features of the invention. Subcombinations of these feature groups can also be inventions.

It is a figure which shows the outline|summary of the image pick-up element 400 which concerns on this embodiment. An example of a specific configuration of the pixel unit 110 is shown. An example of the circuit configuration of the pixel 112 is shown. FIG. 10B schematically shows a plan view of the pixel 112 viewed from the Z direction, which is the optical axis direction. An example of a more specific configuration of the processing circuit section 210 is shown. A cross section of the imaging device 400 is schematically shown. A cross section of a modified example of the imaging device 400 is schematically shown. A cross section of still another modified example of the imaging device 400 is schematically shown. FIG. 9 shows a timing chart of pixel signal readout in the imaging device 400 of FIG. 8 ; FIG. FIG. 10 schematically shows a plan view of another example of the pixel 112 as seen from the Z direction, which is the optical axis direction. FIG. 11 schematically shows a cross section of an imaging device 400 using the pixels 112 of FIG. 10. FIG. An example of electrical operation when another active element is provided in the light shielding layer 156 is shown. FIG. 10 schematically shows a plan view of still another example of the pixel 112 as seen from the Z direction, which is the optical axis direction. FIG. 13 schematically shows a cross section of an imaging device 400 using the pixels 112 of FIG. 13. FIG. 2 is a block diagram showing a configuration example of an imaging device 500 according to an embodiment; FIG.

Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. Also, not all combinations of features described in the embodiments are essential for the solution of the invention.

In this specification, the X-axis and the Y-axis are orthogonal to each other, and the Z-axis is orthogonal to the XY plane. The XYZ axes constitute a right-handed system. A direction parallel to the Z-axis may be referred to as a stacking direction of the imaging device 400 . In this specification, the terms "upper" and "lower" are not limited to vertical directions in the direction of gravity. These terms refer only to relative directions in the Z-axis direction. In this specification, the arrangement in the X-axis direction is described as a "row" and the arrangement in the Y-axis direction is described as a "column," but the matrix direction is not limited to this. Also, the Z-axis direction is the optical axis direction on which the light from the subject is incident.

FIG. 1 is a diagram showing an overview of an imaging device 400 according to this embodiment. The imaging element 400 images a subject. The imaging device 400 generates image data of a captured subject. The image pickup device 400 includes a first substrate 100 and a second substrate 200 . As shown in FIG. 1, the first substrate 100 is laminated on the second substrate 200 .

The first substrate 100 has a pixel section 110 . The pixel unit 110 outputs pixel signals based on incident light. Note that the first substrate 100 is sometimes called a pixel chip.

The second substrate 200 has a processing circuit section 210 and a peripheral circuit section 230 . Note that the second substrate 200 may be called a signal processing chip.

A pixel signal output from the first substrate 100 is input to the processing circuit unit 210 . The processing circuit unit 210 processes input pixel signals. For example, the processing circuit unit 210 performs processing for converting analog signals into digital signals. Specifically, the processing circuit unit 210 performs a process of converting an input pixel signal into a digital signal. Processing circuitry 210 may perform other signal processing. Examples of other signal processing include noise reduction processing such as analog or digital CDS (Correlated Double Sampling).

The processing circuit section 210 of this example is arranged at a position facing the pixel section 110 on the second substrate 200 . That is, the processing circuit section 210 is arranged so as to at least partially overlap the pixel section 110 in the optical axis direction. The processing circuit section 210 may output a control signal for controlling driving of the pixel section 110 to the pixel section 110 .

The peripheral circuit section 230 controls driving of the processing circuit section 210 . The peripheral circuit section 230 is arranged around the processing circuit section 210 on the second substrate 200 . Also, the peripheral circuit section 230 may be electrically connected to the first substrate 100 to control driving of the pixel section 110 .

The imaging device 400 may have a third substrate laminated on the second substrate 200 in addition to the first substrate 100 and the second substrate 200 . For example, the third substrate is a memory chip and performs image processing according to the signal output by the second substrate 200 . Further, the structure of the imaging device 400 may be of a backside illumination type or a front side illumination type. An example of the backside illumination type will be described below.

FIG. 2 shows an example of a specific configuration of the pixel section 110. As shown in FIG. In this example, an enlarged view of a pixel section 110 and a pixel block 120 provided in the pixel section 110 is shown.

The pixel section 110 has a plurality of pixel blocks 120 arranged side by side along the row direction and the column direction. The pixel unit 110 of this example has M×N (M and N are natural numbers) pixel blocks 120 . This example illustrates the case where M is equal to N, but M and N may be different.

Pixel block 120 has at least one pixel 112 . The pixel block 120 of this example has m×n (m and n are natural numbers) pixels 112 . For example, pixel block 120 has 16×16 pixels 112 . The number of pixels 112 corresponding to the pixel block 120 is not limited to this. This example illustrates the case where m is equal to n, but m may be different from n. The number of pixels 112 corresponding to the pixel block 120 may be one. A pixel block 120 has a plurality of pixels 112 connected to a common control line in the row direction. For example, each pixel 112 of pixel block 120 is connected to a common control line so as to be set to the same exposure time. In one example, n pixels 112 arranged in the row direction are connected by a common control line.

On the other hand, different exposure times may be set between the plurality of pixel blocks 120 . That is, each pixel 112 of the pixel block 120 has the same exposure time, but other pixel blocks 120 may have different exposure times. For example, when the pixels 112 of the pixel block 120 are connected by a common control line in the row direction, the pixels 112 of the other pixel blocks 120 are commonly connected by different control lines.

The pixel blocks 120 are arranged corresponding to processing blocks 220 which will be described later. In this embodiment, one pixel block 120 is arranged for one processing block 220 .

The pixel 112 has a photoelectric conversion function of converting light into charge. The pixels 112 accumulate photoelectrically converted charges. The m pixels 112 are arranged side by side along the column direction and connected to a common signal line 122 . The m pixels 112 are arranged in n columns in the row direction in the pixel block 120 .

In other words, pixel block 120 is a group of pixels 112 connected by a common control line. Also, the pixel block 120 can be said to be the minimum circuit unit of a plurality of pixels 112 for which the same exposure time is set.

FIG. 3 shows an example of the circuit configuration of the pixel 112, and FIG. 4 shows a schematic plan view of the pixel 112 viewed from the Z direction, which is the optical axis direction. The pixel 112 includes a photoelectric conversion unit 104 , a transfer unit 123 , a reset unit 126 and a pixel output unit 127 . The pixel output section 127 has an amplification section 128 and a selection section 129 . In this example, the transfer unit 123, the reset unit 126, the amplifier unit 128, and the selection unit 129 are described as N-channel FETs, but the type of transistor is not limited to this.

The photoelectric conversion unit 104 has a photoelectric conversion function of converting light into charge. The photoelectric conversion unit 104 accumulates photoelectrically converted charges. The photoelectric conversion unit 104 is, for example, a photodiode. The photoelectric conversion section 104 has an injection region 106 implanted with an impurity and having a photoelectric conversion function, and an isolation region 108 disposed around the injection region 106 and isolating the injection region 106 from other elements.

The transfer unit 123 transfers the charges accumulated in the photoelectric conversion unit 104 to the accumulation unit 125 . The transfer unit 123 is an example of a transfer gate that transfers charges of the photoelectric conversion unit 104 . In other words, the transfer section 123 as a gate, the photoelectric conversion section 104 as a source, and the storage section 125 as a drain constitute a so-called transfer transistor. A gate terminal of the transfer unit 123 is connected to a local transfer control line 141 for each pixel block 120 for inputting the control signal φTX1.

The charge from the photoelectric conversion unit 104 is transferred to the accumulation unit 125 by the transfer unit 123 . The accumulation unit 125 is an example of floating diffusion (FD).

The reset unit 126 discharges the charge of the storage unit 125 to the power supply wiring supplied with the predetermined power supply voltage VDD. A gate terminal of the reset section 126 is connected to a global reset control line 143 over a plurality of pixel blocks 120 for inputting a reset control signal φRST.

The pixel output section 127 outputs a signal based on the potential of the storage section 125 to the signal line 122 . The pixel output section 127 has an amplification section 128 and a selection section 129 . The amplifying unit 128 has a gate terminal connected to the storage unit 125 , a drain terminal connected to a power supply line supplied with the power supply voltage VDD, and a source terminal connected to the drain terminal of the selection unit 129 .

The selection unit 129 controls electrical connections between the pixels 112 and the signal lines 122 . When the pixel 112 and the signal line 122 are electrically connected by the selection unit 129 , a pixel signal is output from the pixel 112 to the signal line 122 . A gate terminal of the selection section 129 is connected to a global selection control line 144 extending over a plurality of pixel blocks 120 for inputting a selection control signal φSEL. A source terminal of the selector 129 is connected to the load current source 121 .

The load current source 121 supplies current to the signal line 122 . The load current source 121 may be provided on the first substrate 100 or may be provided on the second substrate 200 .

Hereinafter, any of the charge accumulated in the photoelectric conversion unit 104, the charge transferred to the accumulation unit 125, and the signal based on the potential of the accumulation unit 125, or these may be collectively referred to as a pixel signal.

Additionally, the pixel 112 includes at least one photoelectric conversion unit 104 and a pixel output unit 127 as a readout unit that reads out image signals from the at least one photoelectric conversion unit 104 to the signal line 122 . It can be said that the pixel 112 is the minimum unit of a circuit that outputs pixel signals forming an image to the signal line 122 .

The pixel 112 further has a light shielding layer 150 provided so as to cover the photoelectric conversion section 104 when viewed from the Z direction, that is, the optical axis direction. The light shielding layer 150 will be described later.

FIG. 5 shows an example of a more specific configuration of the processing circuit section 210. As shown in FIG. In this example, an enlarged view of a processing circuit unit 210 and a processing block 220 provided in the processing circuit unit 210 is shown.

The processing circuit section 210 has processing blocks 220 arranged side by side along the row direction and the column direction. The processing circuit section 210 of this example has M×N processing blocks 220 .

The processing blocks 220 are arranged at positions corresponding to the pixel blocks 120, respectively. For example, the processing block 220 and the pixel block 120 are arranged at overlapping positions when viewed from the optical axis direction. In this case, the areas of the processing block 220 and the pixel block 120 may be substantially the same including the margins between adjacent blocks.

A processing block 220 controls the driving of the corresponding pixel block 120 . For example, processing block 220 controls the exposure time of pixel block 120 . Also, the processing block 220 has a processing circuit such as an AD converter, and processes the signal output from the pixel block 120 . In one example, processing block 220 converts analog pixel signals output from corresponding pixel blocks 120 to digital signals. The processing block 220 of this example includes an exposure control section 10 , a pixel driving section 20 , a junction section 30 , a signal conversion section 40 and a signal output section 50 .

The exposure control unit 10 controls exposure of the pixels 112 . The exposure controller 10 generates a signal for controlling the exposure time of the pixels 112 . In one example, the exposure control unit 10 controls the exposure time for each pixel block 120 by adjusting at least one of the start timing and end timing of exposure.

The pixel driver 20 is electrically connected to the pixels 112 . The pixel driving section 20 selects and drives an arbitrary pixel 112 from a plurality of pixels 112 based on a signal from the exposure control section 10 . The pixel driving section 20 is arranged at a position corresponding to the m pixels 112 arranged in the column direction. Since the imaging device 400 can set the exposure time for each pixel block 120 according to the intensity of incident light, the dynamic range can be expanded.

The bonding portion 30 bonds the first substrate 100 and the second substrate 200 together. The junction section 30 inputs the pixel signal input from the first substrate 100 to the signal conversion section 40 . The junction section 30 is provided corresponding to n pixels 112 arranged in the row direction, and inputs pixel signals to the signal conversion section 40 for each column.

The signal conversion unit 40 digitally converts the analog signal output from the pixel unit 110 . The signal converter 40 of this example converts analog pixel signals into digital signals. The signal converter 40 sequentially converts the analog signals from the m pixels 112 arranged in the column direction into digital signals. The signal conversion unit 40 parallel-digital-converts the analog signals from the pixels 112 arranged in n columns in the row direction. This can be said to be a so-called column ADC method for one pixel block 120 .

The signal output section 50 receives the digital signal from the signal conversion section 40 . In one example, the signal output section 50 temporarily stores the digital signal. The signal output unit 50 may have a latch circuit for storing digital signals.

Instead of providing one processing block 220 for one pixel block 120, one processing block 220 may be provided for N pixel blocks 120 (N is a natural number equal to or greater than 2). The N pixel blocks 120 corresponding to one processing block are sometimes called a pixel block group. For example, one processing block 220 may be provided with two pixel blocks 120 arranged side by side in the column direction as one pixel block group. In this case, processing block 220 may control the exposure time for each pixel block 120 .

In addition, the processing block 220 is electrically connected to at least one pixel block 120 and can be said to be the minimum unit of a circuit that processes pixel signals of the at least one pixel block 120 . It can also be said that the processing circuit section 210 is composed of a group of processing blocks 220 .

FIG. 6 schematically shows a cross section of the imaging element 400. As shown in FIG. In particular, FIG. 6 shows a cross section through the photoelectric conversion portion 104 and the transfer portion 123 in the pixel 112 . However, FIG. 6 is shown in a simplified manner for the sake of explanation, and the position, size, number, etc. of each component are merely schematic examples unless otherwise specified.

The first substrate 100 has microlenses 180, a planarization layer 181, a color filter 182, a planarization layer 183, a pixel forming region 187, a gate oxide film 188 and a wiring layer 190 along the optical axis direction. A light shielding layer 184 is arranged on the planarization layer 183 . In the pixel formation region 187 , an element isolation portion 186 is arranged together with the configuration of the pixel 112 such as the photoelectric conversion portion 104 and the accumulation portion 125 . A wiring 192 and a light shielding layer 150 are arranged on the wiring layer 190 .

The second substrate 200 has a wiring layer 252, a gate oxide film 256, a circuit region 258 and a substrate 259 along the optical axis direction. A wiring 254 is arranged in the wiring layer 252 . In the circuit area 258, elements of the processing block 220, such as transistors included in the signal conversion section 40, are arranged. The elements may be arranged across other regions. For convenience of explanation, the transistor 260 included in the signal conversion section 40 is shown in FIG. 6 as the element. The first substrate 100 and the second substrate 200 are electrically connected by bumps 193 and 251 facing each other on the bonding surface 250 .

The microlens 180 converges incident light onto the photoelectric conversion unit 104 . The color filter 182 transmits a predetermined wavelength range, ie color, of the light incident on the microlens 180 . The light-shielding layer 184 is a black, metal, or other film that does not transmit visible light, and avoids crosstalk between adjacent pixels 112 in the matrix direction. The element isolation portion 186 is an isolation band that avoids electrical interference with adjacent pixels in the row and column direction.

In the above configuration, an active element included in the processing block 220, such as the transistor 260 included in the signal converter 40, may unintentionally function as a light-emitting diode and emit light when driven. In this case, when the light emitted from the transistor 260 is incident on the photoelectric conversion unit 104, it is photoelectrically converted, and the light from the subject incident from the microlens 180 becomes noise in the pixel signal. For example, infrared rays with a wavelength of about 1000 nm may be emitted from the transistor 260 , and this wavelength is within the range of sensitivity of the photoelectric conversion unit 104 .

Therefore, in the present embodiment, the light shielding layer 150 is provided on the second substrate 200 side of the photoelectric conversion section 104 and at least partially overlaps the photoelectric conversion section 104 in the optical axis direction. In the example shown in FIG. 6, the light blocking layer 150 completely covers the photoelectric conversion section 104 in the optical axis direction.

The light shielding layer 150 preferably blocks light in the wavelength band to which the photoelectric conversion section 104 is sensitive. The light blocking layer 150 may be metal. If the first substrate 100 is made of silicon, the light blocking layer 150 may be polysilicon instead of metal. Further, the light shielding layer 150 may be provided separately from each element of the pixel 112, or the light shielding layer 150 may be formed by adjusting the position and size of part of any element. In this case, for example, the light blocking layer 150 may be an extension of the transfer section 123 . In other words, it can be said that the light shielding layer 150 is integrally connected to the gate terminal of the transfer section 123 .

According to this embodiment, light shielding layer 150 blocks light from processing block 220 , such as transistor 260 . Therefore, noise in pixel signals due to the light can be reduced. In addition, the light shielding layer 150 blocks stray light, in which the light from the subject incident from the microlens 180 passes through the photoelectric conversion unit 104 and is reflected inside the wiring layer 190 to enter the adjacent photoelectric conversion unit 104 . It also has the effect of

FIG. 7 schematically shows a cross section of a modified example of the imaging device 400. As shown in FIG. In FIG. 7, the second substrate 200 is omitted, and the same components as those of the first substrate 100 in FIG.

7, in addition to the light shielding layer 150 of FIG. 6, a black siliconized layer 152 is provided on the surface of the light shielding layer 150 on the second substrate 200 side. The black siliconized layer 152 has, for example, nano-order unevenness on the surface of a silicon layer to reduce the reflectance of infrared and visible light (in other words, it is black with respect to these lights). Black siliconized layer 152 can absorb light from processing block 220 and prevent it from becoming stray light.

Instead of the black siliconized layer 152, a silicided layer may be provided. The silicidation layer is, for example, a layer in which silicon and metal are alloyed, and has a high reflectance with respect to infrared and visible light. The silicidation layer can reflect light from the processing block 220 and more reliably prevent it from entering the photoelectric conversion unit 104 .

FIG. 8 schematically shows a cross section of still another modified example of the imaging device 400, and FIG. 9 shows a timing chart of reading out pixel signals in the imaging device 400 of FIG. In FIG. 8 as well, the second substrate 200 is omitted, and the same reference numerals are given to the same components as those of the first substrate 100 in FIG. 6, and the description thereof is omitted.

In FIG. 8, the light shielding layer 150 is electrically connected to the storage section 125 by the wiring section 154 . Therefore, when photoelectric conversion occurs in the light shielding layer 150 due to light incident on the light shielding layer 150 from the processing block 220 , charges due to the photoelectric conversion are accumulated in the accumulation unit 125 .

That is, as shown in FIG. 9, charges from the light shielding layer 150 are accumulated as the charge signal φFD during the accumulation time determined by the control signal φTX1. However, before transfer from the charge signal φPD of the photoelectric conversion unit 104, the charge signal φFD of the storage unit 125 is reset by the reset signal φRST. Therefore, the charge signal φFD corresponding to the charge signal φPD of the photoelectric conversion unit 104 is transferred and read without being affected by the charge from the light shielding layer 150 .

FIG. 10 schematically shows a plan view of another example of the pixel 112 as seen from the Z direction, which is the optical axis direction, and FIG. 11 schematically shows a cross section of an imaging device 400 using the pixel 112 of FIG. Also in FIG. 11, the second substrate 200 is omitted, and the same reference numerals are given to the same components as those of the first substrate 100 of FIG. 6, and the description thereof is omitted.

10 and 11, the light shielding layer 156 is electrically insulated from the transfer section 123. In FIG. Instead, it has a connection wiring 146 that electrically connects the light shielding layer 156 to the power supply potential.

The light shielding layer 156 does not cover a portion of the photoelectric conversion unit 104 on the side closer to the transfer unit 123 when viewed in the optical axis direction, but covers most of the other portion. Therefore, in the examples of FIGS. 10 and 11 as well, the light shielding layer 156 blocks most of the light from the processing block 220, such as the transistor 260, so that the noise in the pixel signal due to the light can be reduced. In addition, since the light shielding layer 156 is electrically connected to the power supply potential, electric charges photoelectrically converted in the light shielding layer 156 can be discharged through the connection wiring 146 . Therefore, it is possible to suppress the influence of the charge photoelectrically converted in the light shielding layer 156 on the pixel signal.

It should be noted that instead of connecting the light shielding layer 156 to the power supply potential, the connection wiring 146 may be used to connect the light shielding layer 156 to the ground potential. As yet another example, light blocking layer 156 may be biased with a negative voltage. This serves as a countermeasure against dark current. As yet another example, other active elements that selectively apply a voltage to the light blocking layer 156 may be provided.

FIG. 12 shows an example of electrical operation when another active element is connected to the light shielding layer 156. In FIG. FIG. 12A shows charge accumulation in the photoelectric conversion unit 104, and FIG. 12B shows charge transfer.

As shown in FIG. 12A, a negative voltage is applied to the transfer section 123 during accumulation, and no voltage is applied to the light shielding layer 156 . As a result, charges are accumulated in the photoelectric conversion unit 104 .

As shown in FIG. 12B, a positive voltage is applied to the transfer section 123 and a negative voltage is applied to the light blocking layer 156 during transfer. As a result, the charge accumulated in the photoelectric conversion unit 104 is more reliably transferred to the storage unit 125 via the transfer unit 123 .

FIG. 13 schematically shows a plan view of still another example of the pixel 112 as seen from the Z direction, which is the optical axis direction, and FIG. 14 schematically shows a cross section of an imaging device 400 using the pixel 112 of FIG. . Also in FIG. 14, the second substrate 200 is omitted, and the same reference numerals are given to the same components as those of the first substrate 100 of FIG. 6, and the description thereof is omitted.

13 and 14, in addition to the light shielding layer 150 of FIG. 6, another light shielding layer 158 is provided on the second substrate 200 side of the light shielding layer 150. FIG. The light shielding layer 158 at least partially overlaps the photoelectric conversion section 104 and the light shielding layer 150 in the optical axis direction.

Also, the light shielding layer 158 of this example is electrically connected to the transfer section 123 . On the other hand, the light shielding layer 150 is electrically connected to the connection wiring 146 . According to this example, since the light-shielding layer 150 and the light-shielding layer 158 are doubled, the light from the processing block 220 such as the transistor 260 is blocked more reliably, and the noise in the pixel signal due to the light is reduced. be able to. In addition, the charge accumulated in the light shielding layer 150 can be discharged through the connection wiring 146, and the charge can be used to assist the transfer of the photoelectric conversion unit 104. FIG.

The light shielding layers 150 and the like shown in FIGS. 6 to 14 may be combined. Further, instead of connecting each light shielding layer to the transfer section 123, it may be connected to another element of the pixel 112, for example, the reset section 126. FIG. In addition, when the light shielding layer 150 and the like are electrically connected to the storage section 125, this corresponds to substantially increasing the capacitance of the storage section 125. FIG. Therefore, overflow of charges in the storage unit 125 is less likely to occur.

Note that in any of the above embodiments, the pixel 112 may be provided with a discharge portion. The discharge unit discharges the charge accumulated in the photoelectric conversion unit 104 to the power supply wiring supplied with the power supply voltage VDD. As another example, the transfer unit 123 may be omitted. In that case, the storage section 125 no longer functions as a floating diffusion. Also, the storage unit 125 and the pixel output unit 127 may be shared with other pixels. Also, the pixel 112 may be configured with a plurality of photoelectric conversion units 104 and transfer units 123 .

Furthermore, in any of the above-described embodiments, the processing block 220 is not provided with the exposure control unit 10 and the pixel driving unit 20, and reading is mainly performed for each processing block 220 to perform conversion by the signal conversion unit 40. good. In this case, the exposure time of the pixels 112 is controlled not for each pixel block 120 but for the entire pixel section 110 .

FIG. 15 is a block diagram showing a configuration example of an imaging device 500 according to the embodiment. The imaging apparatus 500 includes an imaging device 400, a system control unit 501, a driving unit 502, a photometry unit 503, a work memory 504, a recording unit 505, a display unit 506, a driving unit 514, and an imaging lens 520. Prepare.

The photographing lens 520 guides subject light beams incident along the optical axis OA to the image sensor 400 . The photographing lens 520 is composed of a plurality of optical lens groups, and forms an image of subject light flux from a scene in the vicinity of its focal plane. The imaging lens 520 may be an interchangeable lens that can be attached to and detached from the imaging device 500 . Note that FIG. 15 represents the photographing lens 520 by a single virtual lens arranged near the pupil.

A driving unit 514 drives a photographing lens 520 . In one example, the drive unit 514 moves the optical lens group of the taking lens 520 to change the focus position. Further, the driving unit 514 may drive the iris diaphragm in the photographing lens 520 to control the light amount of the subject light flux incident on the imaging device 400 .

The drive unit 502 has a control circuit that executes charge accumulation control such as timing control and area control of the image sensor 400 according to instructions from the system control unit 501 . Further, the operation unit 508 receives instructions from the photographer using a release button or the like.

The image pickup device 400 transfers pixel signals to the image processing unit 511 of the system control unit 501 . The image processing unit 511 generates image data by performing various image processing using the work memory 504 as a workspace. For example, when generating image data in the JPEG file format, compression processing is executed after a color video signal is generated from the signal obtained in the Bayer array. The generated image data is recorded in the recording unit 505, converted into a display signal, and displayed on the display unit 506 for a preset time.

A photometry unit 503 detects the luminance distribution of a scene prior to a series of shooting sequences for generating image data. The photometry unit 503 includes, for example, an AE sensor with approximately one million pixels. A calculation unit 512 of the system control unit 501 receives the output of the photometry unit 503 and calculates the brightness for each area of the scene.

A calculation unit 512 determines the shutter speed, the aperture value, and the ISO sensitivity according to the calculated luminance distribution. The photometry unit 503 may also be used by the image sensor 400 . Note that the calculation unit 512 also executes various calculations for operating the imaging device 500 . The drive unit 502 may be partially or wholly mounted on the imaging device 400 . A part of the system control unit 501 may be mounted on the imaging device 400 .

Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is obvious to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the description of the scope of claims that forms with such modifications or improvements can also be included in the technical scope of the present invention.

The execution order of each process such as actions, procedures, steps, and stages in the devices, systems, programs, and methods shown in the claims, the specification, and the drawings is particularly "before", "before etc., and it should be noted that they can be implemented in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the specification, and the drawings, even if the description is made using "first," "next," etc. for the sake of convenience, it means that it is essential to carry out in this order. not a thing

10 exposure control section 20 pixel drive section 30 junction section 40 signal conversion section 50 signal output section 100 first substrate 104 photoelectric conversion section 106 injection region 108 isolation region 110 pixel section 112 pixel 120 pixel block, 121 load current source, 122 signal line, 123 transfer section, 125 storage section, 126 reset section, 127 pixel output section, 128 amplification section, 129 selection section, selection section, 141 transfer control line, 143 reset control line, 144 selection control line, 146 connection wiring, 150 light shielding layer, 152 black siliconized layer, 154 wiring portion, 156 light shielding layer, 158 light shielding layer, 180 microlens, 181, 183 planarization layer, 182 color filter, 184 light shielding layer ( between pixels), 186 element isolation portion, 187 pixel formation region, 188 gate oxide film, 190 wiring layer, 192 wiring, 193, 251 bump, 200 second substrate, 210 processing circuit portion, 220 processing block, 250 bonding surface, 252 wiring layer, 254 wiring, 256 gate oxide film, 258 circuit region, 259 substrate, 260 transistor, 400 imaging device, 500 imaging device, 501 system control unit, 502 driving unit, 503 photometry unit, 504 work memory, 505 recording unit, 506 display unit, 508 operation unit, 511 image processing unit, 512 calculation unit, 514 driving unit, 520 photographing lens

Claims (13)

a first substrate having a pixel portion in which a plurality of pixels each having a microlens and a photoelectric conversion portion are provided in a first direction and in a second direction crossing the first direction;
a second substrate having a processing circuit section in which a plurality of processing circuits for processing pixel signals output from the pixels are provided in the first direction and the second direction;
a light shielding layer provided between the first substrate and the second substrate in the optical axis direction of the microlens for shielding light from the processing circuit section;
An image sensor. The imaging device according to claim 1, wherein the pixel section and the processing circuit section are provided in the optical axis direction. 3. The imaging device according to claim 2, wherein the pixels and the processing circuit section are provided in the optical axis direction. The imaging device according to any one of claims 1 to 3, wherein the light shielding layer is provided so as to cover the photoelectric conversion section. 5. The imaging device according to claim 1, wherein the first substrate is a silicon substrate, and the light shielding layer is a polysilicon layer. 6. The imaging device according to claim 5, wherein the surface of the polysilicon layer on the second substrate side is black siliconized. 6. The imaging device according to claim 5, wherein the surface of the polysilicon layer on the side of the second substrate is silicided. each of the plurality of pixels further includes an active element that controls the charge of the photoelectric conversion unit;
The imaging device according to any one of claims 1 to 7, wherein the light shielding layer is integrally connected to the gate of the active device. each of the plurality of pixels,
an active element that controls the charge of the photoelectric conversion unit;
8. The imaging device according to any one of claims 1 to 7, further comprising another active device that selectively applies a voltage to the light shielding layer. 8. The imaging device according to any one of claims 1 to 7, wherein the light shielding layer has a connection wiring electrically connected to one of a power supply potential and a ground potential. 2. Each of the plurality of pixels further includes another light shielding layer that at least partially overlaps with the photoelectric conversion section and the light shielding layer in the optical axis direction, closer to the second substrate than the light shielding layer. 11. The imaging device according to any one of 10. the pixel unit has a first pixel block and a second pixel block each having a pixel;
The processing circuit section has a first processing circuit block for processing pixel signals output from the first pixel block and a second processing circuit block for processing pixel signals output from the second pixel block. ,
The first processing circuit block is provided at a position corresponding to the first pixel block in the optical axis direction,
The imaging device according to any one of claims 1 to 11, wherein the second processing circuit block is provided at a position corresponding to the second pixel block in the optical axis direction. An imaging device comprising the imaging device according to claim 1 .

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