JP6970595B2 - Solid-state image sensor, manufacturing method of solid-state image sensor, and electronic equipment - Google Patents

Description

The present invention relates to a solid-state image sensor, a method for manufacturing a solid-state image sensor, and an electronic device.

A CMOS (Complementary Metal Oxide Semiconductor) image sensor is put into practical use as a solid-state image sensor (image sensor) using a photoelectric conversion element that detects light and generates electric charges.
CMOS image sensors are widely applied as part of various electronic devices such as digital cameras, video cameras, surveillance cameras, medical endoscopes, personal computers (PCs), and mobile terminal devices (mobile devices) such as mobile phones. There is.

The CMOS image sensor has an FD amplifier having a photodiode (photoelectric conversion element) and a floating diffusion layer (FD) for each pixel, and its readout selects a certain line in the pixel array. However, the column parallel output type that reads them out in the column direction at the same time is the mainstream.

Each pixel of the CMOS image sensor, for example, for one photodiode, has a transfer transistor as a transfer gate, a reset transistor as a reset gate, a source follower transistor as a source follower gate (amplification gate), and a selection gate. It is configured to include four elements of the selection transistor as active elements (see, for example, Patent Document 1).

A CMOS image sensor generally captures a color image using a three primary color filter of red (R), green (G), and blue (B) and a four complementary color filter of cyan, magenta, yellow, and green.

Generally, in a CMOS image sensor, each pixel is individually provided with a filter. The filter consists of a group of pixels in which four filters are squarely arranged: a red (R) filter that mainly transmits red light, a green (Gr, Gb) that mainly transmits green light, and a blue (B) filter that mainly transmits blue light. It is arranged two-dimensionally as a unit RGB pixel group.

Further, the incident light to the CMOS image sensor is received by the photodiode through the filter. Since the photodiode receives light in a wavelength range (380 nm to 1100 nm) wider than the human visible region (about 380 nm to 780 nm) and generates a signal charge, an error of the infrared light component occurs and color reproduction occurs. The sex is reduced.
Therefore, it is common to remove infrared light in advance with an infrared cut filter (IR filter).
However, since the IR filter attenuates visible light by about 10% to 20%, it lowers the sensitivity of the solid-state image sensor and causes deterioration in image quality.

Therefore, a CMOS image sensor (solid-state image sensor) that does not use an IR filter has been proposed (see, for example, Patent Document 2).
This CMOS image sensor mainly includes an R pixel containing a red (R) filter that transmits red light, a G pixel that includes a green (G) filter that mainly transmits green light, and a blue (B) filter that mainly transmits blue light. A pixel group in which four of the included B pixel and the dedicated near-infrared (NIR) pixel that receives infrared light are squarely arranged is arranged two-dimensionally as a unit RGBIR pixel group.

In this CMOS image sensor, the output signal of the pixel that receives infrared light is used to correct the output signal of the pixel that receives red, green, and blue light, so that high color reproducibility is achieved without using an IR filter. Can be realized.

Further, in the CMOS image sensor provided with the unit RGB pixel group or the unit RGBIR pixel group, the four pixels of the unit pixel group include a floating diffusion FD, a reset transistor RST-Tr, a source follower transistor SF-Tr, and a selection transistor SEL. -Tr may be shared.

Further, in an imaging device such as a digital camera, as a method for realizing automatic focus adjustment (autofocus (AF)), for example, the phase difference information of autofocus (AF) is obtained from a part of the pixels of the pixel array unit. A phase difference detection method such as an image plane phase difference method is known in which autofocus is performed by arranging phase difference detection pixels for the purpose.

In the image plane phase difference method, for example, half of the light receiving area of the pixel is shielded by a light-shielding film, and the phase difference on the image plane is measured by the phase difference detection pixel that receives light in the right half and the phase difference detection pixel that receives light in the left half. Detect (see, for example, Patent Document 3).

On the other hand, a signal obtained by a pair of photoelectric conversion units (photodiodes) by dividing the photoelectric conversion unit (photodiode (PD)) in the pixel into two (providing two) without using a light-shielding film. A method of detecting a phase difference based on the amount of phase shift of the above is known (see, for example, Patent Documents 4 and 5).
This phase difference detection method is also called a pupil division method, in which the light flux passing through the image pickup lens is divided into pupils to form a pair of divided images, and the pattern shift (phase shift amount) is detected to detect the phase shift of the image pickup lens. Detect the amount of focus.
In this case, the phase difference detection is unlikely to be a defective pixel, and by adding the divided photoelectric conversion unit (PD) signal, it can be used as a good image signal.

In the solid-state image pickup device disclosed in Patent Document 4, a plurality of pixels having two photoelectric conversion units are arranged. A floating diffusion FD is arranged in the center of the pixel between one portion and the other portion of the two photoelectric conversion units, and the two photoelectric conversion units are arranged in parallel with the floating diffusion FD interposed therebetween.
Microlenses are provided on such a photoelectric conversion unit on a one-to-one basis with respect to pixels. The microlens is arranged so that the optical center is located at the center of the pixel.

Also in the solid-state image pickup device disclosed in Patent Document 5, a plurality of pixels having two photoelectric conversion units are arranged. However, the floating diffusion FD is arranged not in the central portion of the pixel between one portion and the other portion of the two photoelectric conversion portions, but in the peripheral portion of the pixel.
Also in this case, the microlens is provided one-to-one with respect to the pixel, and the microlens is arranged so that the optical center is located at the center of the pixel.

The photodiode PD as the photoelectric conversion unit is formed so as to be embedded in a semiconductor substrate having a first substrate surface side and a second substrate surface side on the side facing the first substrate surface side, and receives light. It is formed so as to have a photoelectric conversion function of light and a charge storage function.
Further, in the photodiode as the photoelectric conversion unit, a color filter array is arranged on the first substrate surface side (back surface side). A microlens of a microlens array is arranged on the light incident side of each color filter of the color filter array.
Further, the photodiode PD has a red (R) photoelectric conversion region, a green (G) photoelectric conversion region, a blue (B) photoelectric conversion region, and a near infrared (NIR) photoelectric conversion region on the second substrate surface side (front side). ) Is formed with an output unit including an output transistor or the like that outputs a signal corresponding to the charge that has been photoelectrically converted and accumulated.

FIG. 1 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in a solid-state image sensor including near-infrared (NIR) pixels.
FIG. 2 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in a solid-state image sensor using a light-shielding film for phase difference detection.
FIG. 3 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in a solid-state image sensor using two photodiodes for phase difference detection.
In addition, in FIG. 1, FIG. 2, and FIG. 3, for convenience of understanding, each red (R) pixel PXL1, green (G) pixel PXL2, blue (B) pixel PXL3, and near The components of the infrared (NIR) pixel PXL4 are shown in a row.

In the solid-state image pickup devices 1, 1a, 1b of FIGS. 1, 2, and 3, the color filter array 4 is arranged on the first substrate surface 2 side of the photodiodes PD1, PD2, PD3, PD4 via the flat film 3. Has been done.
Then, on the light incident side of each color filter FLT-R, FLT-G, FLT-B, and the near infrared (NIR) pixel of the color filter array 4, the microlens array 5 as an optical unit (lens unit) The microlenses MCL1, MCL2, MCL3, and MCL4 are arranged so as to have a uniform position and shape.

Further, in the solid-state image sensor 1a of FIG. 2, the light-shielding film SLD-R that shields the light incident optical path over almost half in the flat film 3 on the first substrate surface 2 side of the photodiodes PD1, PD2, PD3, PD4. SLD-G, SLD-B, and SLD-NIR are arranged.

Further, in the solid-state image sensor 1b of FIG. 3, the photodiodes PD1, PD2, PD3, and PD4 are formed so as to be divided into two, respectively.
The photodiode PD1 is divided into two photodiodes PD1L and PD1R, the photodiode PD2 is divided into two photodiodes PD2L and PD2R, the photodiode PD3 is divided into two photodiodes PD3L and PD3R, and the photodiode PD4 is 2. It is divided into two photodiodes, PD4L and PD4R.

Japanese Unexamined Patent Publication No. 2005-223681 JP-A-2017-139286 Patent No. 5157436 Patent No. 4027113 Patent No. 5076528

However, in the solid-state image pickup device as shown in FIGS. 1, 2, and 3, as shown by the broken line in the figure, the microlens MCL1 of the microlens array 5 is different even though the focal length differs depending on the wavelength of the incident light. , MCL2, MCL3, and MCL4 are arranged so as to have a uniform position and shape, which has the following disadvantages.

That is, there is a disadvantage that the crosstalk between pixels is large, especially the crosstalk of the red (R) pixel PXL1 and the near infrared (NIR) pixel PXL4 having a long wavelength is large, and the angler response is deteriorated. ..

Further, in the solid-state image pickup devices 1a and 1b having the phase difference detection function of FIGS. 2 and 3, it is difficult to obtain a sufficient phase difference detection function only for the pixel PXL2 having a specific wavelength such as green (G). be.

The present invention is to provide a solid-state image sensor, a method for manufacturing a solid-state image sensor, and an electronic device capable of reducing crosstalk between pixels and preventing deterioration of angle response. ..

The solid-state imaging device according to the first aspect of the present invention has a pixel portion in which a unit pixel group including a plurality of color pixels for photoelectric conversion is arranged, and the unit pixel group photoelectrically receives light incident from one surface side. A lens having a function of converting and having a plurality of photoelectric conversion units corresponding to the plurality of colors and a plurality of lenses having a focal length depending on the wavelength, which incident light on the corresponding plurality of photoelectric conversion units. includes a part, wherein the lens unit is adjusted so that light transmitted through the plurality of lenses has a uniform focal length to said one side of said plurality of photoelectric conversion unit, the plurality of photoelectric conversion unit Are each divided in a direction parallel to the one surface, and have a phase difference detection function .

A second aspect of the present invention has a pixel unit in which a unit pixel group including a plurality of color pixels for photoelectric conversion is arranged, and the unit pixel group has a plurality of photoelectric conversion units and a plurality of lenses arranged in the unit pixel group. It is a method of manufacturing a solid-state imaging device in which the lens is formed including the lens portion, and has a function of photoelectrically converting light incident from one surface side as a step of forming the unit pixel group. A step of forming a plurality of photoelectric conversion units corresponding to the plurality of colors, and a lens unit in which a plurality of lenses having a focal length dependent on a wavelength, which incident light on the corresponding plurality of photoelectric conversion units, are arranged. In the step of forming the photoelectric conversion unit including the step of forming, the plurality of photoelectric conversion units are each divided in a direction parallel to the one surface to have a phase difference detection function, and the lens unit is provided. In the step of forming the lens, the light transmitted through the plurality of lenses is adjusted so as to have a uniform focal length on the one surface side of the plurality of photoelectric conversion units .

The electronic device according to the third aspect of the present invention includes a solid-state image pickup device and an optical system for forming a subject image on the solid-length image pickup device, and the solid-state image pickup device has a plurality of color pixels that perform photoelectric conversion. The unit pixel group has a pixel unit in which a unit pixel group including the lens is arranged, and the unit pixel group has a function of photoelectrically converting light incident from one surface side, and has a plurality of photoelectric conversion units corresponding to the plurality of colors. The lens unit includes a lens unit in which a plurality of lenses whose focal length depends on the wavelength, which incident light on the plurality of photoelectric conversion units, are arranged, and the lens unit includes the plurality of light transmitted through the plurality of lenses. The photoelectric conversion unit is adjusted so as to have a uniform focal length on the one surface side, and each of the plurality of photoelectric conversion units is divided in a direction parallel to the one surface, and has a phase difference detection function. ..

According to the present invention, it is possible to reduce the crosstalk between pixels and prevent the underground response from deteriorating.
Further, according to the present invention, it is possible to have a good phase difference detection function without depending on the wavelength of the incident light.

FIG. 3 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in a solid-state image sensor including near-infrared (NIR) pixels. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which used the light-shielding film for phase difference detection. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which used two photodiodes for phase difference detection. It is a block diagram which shows the structural example of the solid-state image sensor which concerns on 1st Embodiment of this invention. It is a circuit diagram which shows the example which shares one floating diffusion with four pixels of the pixel part of the solid-state image pickup apparatus which concerns on this 1st Embodiment. It is a figure which shows the structural example of the column signal processing circuit in the read circuit which concerns on this embodiment. It is a figure which shows the schematic arrangement example of each component of the solid-state image sensor (CMOS image sensor) which has a unit pixel group which concerns on this 1st Embodiment in a plane. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which concerns on 1st Embodiment of this invention. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which concerns on 2nd Embodiment of this invention. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which concerns on 3rd Embodiment of this invention. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which concerns on 4th Embodiment of this invention. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which concerns on 5th Embodiment of this invention. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which concerns on 6th Embodiment of this invention. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which concerns on 7th Embodiment of this invention. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which concerns on 8th Embodiment of this invention. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which concerns on 9th Embodiment of this invention. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which concerns on 10th Embodiment of this invention. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which concerns on 11th Embodiment of this invention. It is a simplified sectional view schematically showing the structural example of the unit pixel group in the solid-state image pickup apparatus which concerns on 12th Embodiment of this invention. It is a figure which shows an example of the structure of the electronic device to which the solid-state image sensor which concerns on embodiment of this invention is applied.

Hereinafter, embodiments of the present invention will be described in association with the drawings.

(First Embodiment)
FIG. 4 is a block diagram showing a configuration example of the solid-state image sensor according to the first embodiment of the present invention.
In the present embodiment, the solid-state image sensor 10 is composed of, for example, a CMOS image sensor.

As shown in FIG. 4, the solid-state image sensor 10 includes a pixel unit 20 as an image pickup unit, a vertical scanning circuit (row scanning circuit) 30, a readout circuit (column readout circuit) 40, and a horizontal scanning circuit (column scanning circuit) 50. , And a timing control circuit 60 as a main component.
Further, among these components, for example, a vertical scanning circuit 30, a readout circuit 40, a horizontal scanning circuit 50, and a timing control circuit 60 constitute a pixel signal readout unit 70.

In the present embodiment, the solid-state imaging device 10 has a plurality of color filters in the unit pixel group so that the crosstalk between the pixels can be reduced and the angle response can be prevented from deteriorating. A color filter array in which is arranged and an output unit having a function of photoelectrically converting the light transmitted through each color filter arranged on one side and outputting the charge obtained by the photoelectric conversion are arranged on the other side. In addition, a lens unit in which a plurality of photoelectric conversion units corresponding to a plurality of color filters and a plurality of microlenses whose focal distance depends on the wavelength, which incident light on the corresponding photoelectric conversion units through each color filter, are arranged. When, wherein the lens unit is that is adjusted so that light transmitted through the plurality of micro lenses have a uniform focal length on one side of the plurality of photoelectric conversion unit.
Then, in the first embodiment, the lens unit changes the thickness of each microlens so that the light transmitted through the microlenses has a uniform focal length on one surface side of the plurality of photoelectric conversion units. Has been done.
In the first embodiment, the thickness of each microlens is set to be thicker as the microlens corresponds to light having a longer wavelength, and the design has a larger curvature.
In the first embodiment, the unit pixel group is formed as a unit RGBIR pixel group.

Hereinafter, the outline of the configuration and the function of each part of the solid-state image sensor 10 will be described, and then the specific configuration, arrangement, and the like of the pixels will be described in detail.

(Structure of pixel unit 20 and pixel PXL)
In the pixel unit 20, a plurality of pixels including a photodiode (photoelectric conversion element) and an in-pixel amplifier are arranged in a two-dimensional matrix of N rows × M columns.

FIG. 5 is a circuit diagram showing an example in which one floating diffusion is shared by four pixels of the pixel portion of the solid-state image sensor according to the first embodiment.

In the pixel unit 20 of FIG. 5, four pixels PXL11, PXL12, PXL21, and PXL22 are arranged in a 2 × 2 square.

The pixel PXL11 includes a photodiode PD11 and a transfer transistor TG11-Tr.

The pixel PXL12 includes a photodiode PD12 and a transfer transistor TG12-Tr.

The pixel PXL21 includes a photodiode PD21 and a transfer transistor TG21-Tr.

The pixel PXL22 includes a photodiode PD22 and a transfer transistor TG22-Tr.

The pixel unit 20 consists of four pixels PXL11, PXL12, PXL21, and PXL22, and includes a floating diffusion FD (Floating Diffusion) 11, a reset transistor RST11-Tr, a source follower transistor SF11-Tr, and a selection transistor SEL11-. Tr is shared.

In such a 4-pixel sharing configuration, in the case of a bayer arrangement, the pixel PXL11 is formed as an R pixel, the pixel PXL12 is formed as a G pixel, the pixel PXL21 is formed as a B pixel, and the pixel PXL22 is formed as a NIR pixel.
For example, the photodiode PD11 of the pixel PXL11 functions as a red (R) photoelectric conversion unit, the photodiode PD12 of the pixel PXL12 functions as a green (G) photoelectric conversion unit, and the photodiode PD21 of the pixel PXL21 functions as a blue (B) photoelectric conversion unit. It functions as a conversion unit, and the photodiode PD22 of the pixel PXL22 functions as a near-infrared (NIR) photoelectric conversion unit.

In general, the sensitivity to saturation of the photodiode PD of each pixel is different for each color.
For example, the sensitivity of the photodiode PD12 of the G pixel is higher than the sensitivity of the photodiode PD11 of the R pixel, the photodiode PD21 of the B pixel, and the photodiode PD22 of the NIR pixel.

As the photodiodes PD11, PD12, PD21, and PD22, for example, an embedded photodiode (PPD) is used.
Since surface levels due to defects such as dangling bonds exist on the surface of the substrate forming the photodiodes PD11, PD12, PD21, and P22, a large amount of electric charge (dark current) is generated by thermal energy, and the correct signal can be read out. It will disappear.
In the embedded photodiode (PPD), by embedding the charge storage portion of the photodiode PD in the substrate, it is possible to reduce the mixing of dark current into the signal.

The photodiodes PD11, PD12, PD21, and PD22 generate and accumulate a signal charge (here, an electron) in an amount corresponding to the amount of incident light.
Hereinafter, the case where the signal charge is an electron and each transistor is an n-type transistor will be described, but the signal charge may be a hole or each transistor may be a p-type transistor.

The transfer transistor TG11-Tr is connected between the photodiode PD11 and the floating diffusion FD11 and is controlled through the control line (or control signal) TG11.
In the transfer transistor TG11-Tr, under the control of the readout unit 70, the control line TG11 is selected during a high level (H) period of a predetermined level to be in a conductive state, and the charge (electrons) converted by photoelectric conversion by the photodiode PD11 and accumulated is obtained. ) Is transferred to the floating diffusion FD11.

The transfer transistor TG12-Tr is connected between the photodiode PD12 and the floating diffusion FD11 and is controlled through the control line (or control signal) TG12.
In the transfer transistor TG12-Tr, under the control of the readout unit 70, the control line TG12 is selected during a high level (H) period of a predetermined level to be in a conductive state, and the charge (electrons) converted by photoelectric conversion by the photodiode PD12 and accumulated is obtained. ) Is transferred to the floating diffusion FD11.

The transfer transistor TG21-Tr is connected between the photodiode PD21 and the floating diffusion FD11 and is controlled through the control line (or control signal) TG21.
In the transfer transistor TG21-Tr, under the control of the readout unit 70, the control line TG21 is selected during a high level (H) period of a predetermined level to be in a conductive state, and the charge (electrons) converted by photoelectric conversion by the photodiode PD21 and accumulated. ) Is transferred to the floating diffusion FD11.

The transfer transistor TG22-Tr is connected between the photodiode PD22 and the floating diffusion FD11 and is controlled through the control line (or control signal) TG22.
In the transfer transistor TG22-Tr, under the control of the readout unit 70, the control line TG22 is selected during a high level (H) period of a predetermined level to be in a conductive state, and the charge (electrons) converted by photoelectric conversion by the photodiode PD22 and accumulated is obtained. ) Is transferred to the floating diffusion FD11.

As shown in FIG. 5, the reset transistor RST11-Tr is connected between the power supply line VDD and the floating diffusion FD, and is controlled through the control line (or control signal) RST11.
The reset transistor RST11-Tr may be connected between the power supply line VRst and the floating diffusion FD, which are different from the power supply line VDD, and may be configured to be controlled through the control line (or control signal) RST11.
Under the control of the read unit 70, for example, during a read scan, the reset transistor RST11-Tr is selected for the control line RST11 during the H level period to be in a conductive state, and the floating diffusion FD11 is set to the potential of the power supply line VDD (or VRst). Reset.

The source follower transistor SF11-Tr and the selection transistor SEL11-Tr are connected in series between the power supply line VDD and the vertical signal line LSGN.
A floating diffusion FD11 is connected to the gate of the source follower transistor SF11-Tr, and the selection transistor SEL11-Tr is controlled through the control line (or control signal) SEL11.
The selection transistor SEL11-Tr is in a conductive state when the control line SEL11 is selected during the H level period. As a result, the source follower transistor SF11-Tr outputs the read voltage (signal) VSL (PIXOUT) of the column output, which is obtained by converting the charge of the floating diffusion FD11 into a voltage signal with a gain corresponding to the amount of charge (potential), to the vertical signal line LSGN. do.

Since the pixels PXL are arranged in N rows × M columns in the pixel unit 20, there are N lines for each control line SEL, RST, and TG, and M lines for each of the vertical signal lines LSGN.
In FIG. 4, each control line (or control signal) SEL, RST, and TG is represented as one row scanning control line.

The vertical scanning circuit 30 drives the pixels through the row scanning control lines in the shutter row and the readout row according to the control of the timing control circuit 60.
Further, the vertical scanning circuit 30 outputs a row selection signal of a lead row that reads out the signal according to the address signal and a row address of the shutter row that resets the charge accumulated in the photodiode PD.

In a normal pixel readout operation, a shutter scan is performed by driving the vertical scanning circuit 30 of the readout unit 70, and then a readout scan is performed.

The readout circuit 40 includes a plurality of column signal processing circuits (not shown) arranged corresponding to each column output of the pixel unit 20, and even if the plurality of column signal processing circuits are configured to enable column parallel processing. good.

The readout circuit 40 can be configured to include a Correlated Double Sampling (CDS) circuit, an ADC (analog digital converter; AD converter), an amplifier (AMP, amplifier), a sample hold (S / H) circuit, and the like. Is.

As described above, as shown in FIG. 6A, for example, the read circuit 40 may include an ADC 41 that converts the read signal VSL of each column output of the pixel unit 20 into a digital signal.
Alternatively, as shown in FIG. 6B, for example, the readout circuit 40 may include an amplifier (AMP) 42 that amplifies the readout signal VSL of each column output of the pixel unit 20.
Further, in the read circuit 40, for example, as shown in FIG. 6C, a sample hold (S / H) circuit 43 that samples and holds the read signal VSL of each column output of the pixel unit 20 may be arranged.

The horizontal scanning circuit 50 scans signals processed by a plurality of column signal processing circuits such as the ADC of the readout circuit 40, transfers them in the horizontal direction, and outputs the signals to a signal processing circuit (not shown).

The timing control circuit 60 generates timing signals necessary for signal processing of the pixel unit 20, the vertical scanning circuit 30, the reading circuit 40, the horizontal scanning circuit 50, and the like.

The outline of the configuration and function of each part of the solid-state image sensor 10 has been described above.
Next, a specific configuration of the pixel arrangement according to the first embodiment will be described.

FIG. 7 is a diagram showing a schematic arrangement example of each component of a solid-state image sensor (CMOS image sensor) having a unit pixel group according to the first embodiment in a plan view.

The pixel portion 20 of FIG. 7 is shown by flattening the circuit of FIG. 5, and four pixels PXL11, PXL12, PXL21, and PXL22 are arranged in a 2 × 2 square.
More specifically, in the rectangular arrangement area AR10, the arrangement areas AR11, AR12, AR21, and AR22 in which the four pixels PXL11, PXL12, PXL21, and PXL22 are arranged, respectively, are allocated to 2 × 2 squares.

The pixel portion 20 of FIG. 7 shows a configuration in the case of a bayer arrangement in a 4-pixel sharing configuration, in which the pixel PXL 11 is formed as an R pixel, the pixel PXL 12 is formed as a G pixel, the pixel PXL 21 is a B pixel, and the pixel PXL 22. Is formed as NIR pixels.

The pixel unit 20 is composed of four pixels PXL11, PXL12, PXL21, and PXL22, and shares a floating diffusion FD11, a reset transistor RST11-Tr, a source follower transistor SF11-Tr, and a selection transistor SEL11-Tr.

FIG. 8 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in the solid-state image sensor according to the first embodiment of the present invention.
In FIG. 8, for convenience, each red (R) pixel PXL11, green (G) pixel PXL12, blue (B) pixel PXL21, and near infrared (NIR) PXL22 are configured for ease of understanding. The elements are shown in a row.

The unit RGB NIR pixel group 200 includes a microlens array 210 as a lens unit, a color filter array 220, a photodiode array 230 as a photoelectric conversion unit, and a flat layer 240 as main components.

Each color pixel in this unit RGB NIR pixel group 200 not only has a specific responsiveness inherent in the visible range (400 nm to 700 nm), but also has a high responsiveness in the near infrared (NIR) region (800 nm to 1000 nm). Have.

The color filter array 220 is divided into a red (R) filter region 221, a green (G) filter region 222, a blue (B) filter region 223, and a near infrared (NIR) region 224 so as to form each color pixel. Has been done.

The photodiodes PD11, PD12, PD21, and PD22 as photoelectric conversion units have a reference to a semiconductor substrate 250 having a first substrate surface 251 side and a second substrate surface 252 side facing the first substrate surface 251 side. It is formed so as to be embedded, and has a photoelectric conversion function and a charge storage function of the received light.

In the photodiodes PD11, PD12, PD21, and PD22 of the photodiode array 230, the color filter array 220 is arranged on the first substrate surface 251 side (back surface side) via the flat layer 240.
On the second substrate surface 252 side (front side) of the photodiodes PD11, PD12, PD21, and PD22, output units 231, 232, 233, 234 including an output transistor that outputs a signal corresponding to the charge obtained by photoelectric conversion and accumulated are included. Is formed.

The microlens of the microlens array 210 is located on the light incident side of each red (R) filter region 221, green (G) filter region 222, blue (B) filter region 223, and near infrared (NIR) region 224. MCL-R, MCL-G, MCL-B, and MCL-NIR are arranged.

The microlenses MCL-R, MCL-G, MCL-B, and MCL-NIR have the same transmission characteristics, the focal length has wavelength dependence, and the focal length differs depending on the wavelength of the incident light.
Therefore, in the first embodiment, the photodiodes PD11, PD12, PD21, in which the light transmitted through the plurality of microlenses MCL-R, MCL-G, MCL-B, MCL-NIR is a plurality of photoelectric conversion units, the first substrate surface 251 side of the PD 22 (one side, back surface side), that is adjusted to have a uniform focal distance.

In the first embodiment, the thickness of each microlens MCL-R, MCL-G, MCL-B, and MCL-NIR is set to be thicker as the microlens corresponds to light having a longer wavelength.
Microlens for near-infrared (NIR) light with the longest wavelength MCL-NIR thickness LT-NIR is set with the thickest, thickest and largest curvature, and the micro for red (R) light with the second longest wavelength. The thickness LT-R of the lens MCL-R is set to the second thickest and the second largest curvature, and the thickness LT-G of the microlens MCL-G for green (R) light having the third longest wavelength is 3 The thickness LT-B of the microlens MCL-B for blue (B) light, which is the third thickest and is set with the third largest curvature, and has the fourth longest wavelength, is set with the fourth thickest and the second largest curvature. There is.
That is, the thickness of each microlens MCL-R, MCL-G, MCL-B, and MCL-NIR is adjusted so as to have the relationship of LT-NIR>LT-R>LT-G> LT-B. ..

In the unit RGB NIR pixel group 200, the thickness LT-NIR of the microlens MCL-NIR for near-infrared (NIR) light having the longest wavelength is set to be the thickest, and for red (R) light having the second longest wavelength. The thickness LT-R of the microlens MCL-R is set to the second thickest, and the thickness LT-G of the microlens MCL-G for green (R) light having the third longest wavelength is set to the third thickest. The thickness LT-B of the microlens MCL-B for blue (B) light having the fourth longest wavelength is set to be the fourth thickest.
As a result, the incident light transmitted through each of the microlenses MCL-R, MCL-G, MCL-B, and MCL-NIR is the corresponding red (R) pixel PXL11, green (G) pixel PXL12, and blue (B) pixel PXL21. For each near-infrared (NIR) pixel PXL22, the first surface 251 side of the substrate 250 is individually and uniformly irradiated, and unnecessary incidents on the photodiode PD not in charge are greatly reduced.
Therefore, the crosstalk between pixels is significantly reduced, and the deterioration of the underground response is prevented.

As described above, according to the first embodiment, in the solid-state imaging device 10, the unit pixel group 200 includes a color filter array 220 in which a plurality of color filters are arranged and each color filter arranged on one side. A photodiode array having a plurality of photodiodes corresponding to a plurality of color filters, in which an output unit having a function of photoelectrically converting the light transmitted through the capacitor and outputting the charge obtained by the photoelectric conversion is arranged on the other side. wherein 230 is incident light to the plurality of photoelectric conversion units corresponding through each color filter, a microlens array 210 as a lens unit in which a plurality of microlenses are arranged the focal length depends on the wavelength, a plurality microlenses MCL-R, MCL-G, MCL-B, that the light transmitted through the MCL-NIR has not been adjusted to have a uniform focal length on one side of the plurality of photodiodes.

Then, in the first embodiment, the lens portion changes the curvature of the lens by changing the thickness of each microlens MCL-R, MCL-G, MCL-B, MCL-NIR, and transmits the microlens. The light is adjusted so that it has a uniform focal length on one side of a plurality of photoelectric conversion units.
In the first embodiment, the thickness of each microlens is set to be thicker as the microlens corresponds to light having a longer wavelength, and the design has a larger curvature.
In the first embodiment, the thickness LT-NIR of the microlens MCL-NIR for near-infrared (NIR) light having the longest wavelength is set to the thickest and the largest curvature, and the wavelength is the second longest red. (R) Thickness of microlens MCL-R for (R) light LT-R is set with the second thickest and second largest curvature, and the wavelength of the microlens MCL-G for green (R) light is the third longest. The thickness LT-G is set to the third thickest and the third largest curvature, and the thickness LT-B of the microlens MCL-B for blue (B) light having the fourth longest wavelength is the fourth thickest and the fourth. Is set with a large curvature.

According to the first embodiment having such a configuration, it is possible to reduce the crosstalk between pixels and prevent the underground response from deteriorating.

(Second embodiment)
FIG. 9 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in the solid-state image sensor according to the second embodiment of the present invention.

The difference between the second embodiment and the first embodiment is as follows.
The unit pixel group 200A of the second embodiment is a light-shielding film SLD11-R that shields the light incident optical path by almost half in the flat film 240 on the first substrate surface 251 side of the photodiodes PD11, PD12, PD21, PD22. , SLD12-G, SLD21-B, and SLD22-NIR are arranged and configured to have a phase detection function.

According to the second embodiment, it is possible to reduce the crosstalk between pixels and prevent the angle response from deteriorating, as in the effect of the first embodiment described above. Moreover, it is possible to obtain a sufficient phase difference detection function for any pixel without depending on the wavelength of the incident light.

(Third embodiment)
FIG. 10 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in the solid-state image sensor according to the third embodiment of the present invention.

The differences between the third embodiment and the first embodiment are as follows.
The unit pixel group 200B of the third embodiment is formed so that the photodiodes PD11, PD12, PD21, and PD22 are each divided into two, and are configured to have a phase detection function.
The photodiode PD11 is divided into two photodiodes PD11L and PD11R, the photodiode PD12 is divided into two photodiodes PD12L and PD12R, the photodiode PD21 is divided into two photodiodes PD21L and PD21R, and the photodiode PD22 is 2. It is divided into two photodiodes PD22L and PD22R.

According to the third embodiment, it is possible to reduce the crosstalk between pixels and prevent the angle response from deteriorating, as in the effect of the first embodiment described above. Moreover, it is possible to obtain a sufficient phase difference detection function for any pixel without depending on the wavelength of the incident light.

(Fourth Embodiment)
FIG. 11 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in the solid-state image sensor according to the fourth embodiment of the present invention.

The differences between the fourth embodiment and the first embodiment are as follows.
In the unit pixel group 200C of the fourth embodiment, instead of adjusting the thickness of each microlens so that the light transmitted through the microlenses has a uniform focal length on one surface side of the plurality of photoelectric conversion units. , The height from the first surface 251 side (one surface side) of the substrate 250 corresponding to the focal length position is adjusted.

In the fourth embodiment, the height of each microlens is set higher as the microlens corresponds to light having a longer wavelength.
In the fourth embodiment, the height LH-NIR of the microlens MCL-NIR for near-infrared (NIR) light having the longest wavelength is set to the highest, and the red (R) light having the second longest wavelength is set. The height LH-R of the microlens MCL-R for light is set to the second thickest, and the height LH-G of the microlens MCL-G for green (R) light having the third longest wavelength is the third highest. The height LH-B of the microlens MCL-B for blue (B) light, which is set and has the fourth longest wavelength, is set to the fourth highest.
That is, the heights of the microlenses MCL-R, MCL-G, MCL-B, and MCL-NIR are adjusted so as to have the relationship of LH-NIR>LH-R>LH-G> LH-B. ..

In the fourth embodiment, the incident light transmitted through the microlenses MCL-R, MCL-G, MCL-B, and MCL-NIR is the corresponding red (R) pixel PXL11 and green (Gr) pixel PXL12. For each of the blue (B) pixel PXL21 and the near-infrared (NIR) pixel PXL22, the first surface 251 side of the substrate 250 is individually and uniformly irradiated, and unnecessary incidents on the photodiode PD, which is not in charge, are significantly increased. Decrease.
Therefore, the crosstalk between pixels is significantly reduced, and the deterioration of the underground response is prevented.

As described above, according to the fourth embodiment, the same effect as that of the first embodiment described above can be obtained.

(Fifth Embodiment)
FIG. 12 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in the solid-state image sensor according to the fifth embodiment of the present invention.

The difference between the fifth embodiment and the fourth embodiment is as follows.
The unit pixel group 200D of the fifth embodiment is a light-shielding film SLD11-R that shields the light incident optical path by almost half in the flat film 240 on the first substrate surface 251 side of the photodiodes PD11, PD12, PD21, and PD22. , SLD12-G, SLD21-B, and SLD22-NIR are arranged and configured to have a phase detection function.

According to the fifth embodiment, it is possible to reduce the crosstalk between pixels and prevent the angle response from deteriorating, as in the effect of the fourth embodiment described above. Moreover, it is possible to obtain a sufficient phase difference detection function without depending on the wavelength of the incident light and without depending on the wavelength of the incident light.

(Sixth Embodiment)
FIG. 13 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in the solid-state image sensor according to the sixth embodiment of the present invention.

The difference between the sixth embodiment and the fourth embodiment is as follows.
The unit pixel group 200E of the sixth embodiment is formed so that the photodiodes PD11, PD12, PD21, and PD22 are each divided into two, and are configured to have a phase detection function.
The photodiode PD11 is divided into two photodiodes PD11L and PD11R, the photodiode PD12 is divided into two photodiodes PD12L and PD12R, the photodiode PD21 is divided into two photodiodes PD21L and PD21R, and the photodiode PD22 is 2. It is divided into two photodiodes PD22L and PD22R.

According to the sixth embodiment, it is possible to reduce the crosstalk between pixels and prevent the angle response from deteriorating, as in the effect of the fourth embodiment described above. Moreover, it is possible to obtain a sufficient phase difference detection function for any pixel without depending on the wavelength of the incident light.

(7th Embodiment)
FIG. 14 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in the solid-state image sensor according to the seventh embodiment of the present invention.

The difference between the seventh embodiment and the first embodiment is as follows.
In the unit pixel group 200F of the seventh embodiment, instead of adjusting the thickness of each microlens so that the light transmitted through the microlenses has a uniform focal distance on one surface side of the plurality of photoelectric conversion units. , The light emitting side of each microlens and the first substrate surface 251 side (one surface side) of each photodiode PD11, PD12, PD21, PD22, in this example, is arranged at the arrangement position of the flat film 240, and the microlens. Optical member OPT-R, which guides the light transmitted through MCL-R, MCL-G, MCL-B, and MCL-NIR to the first substrate surface 251 side (one surface side) of each photodiode PD11, PD12, PD21, PD22. OPT-G, OPT-B, and OPT-NIR are provided.

In the seventh embodiment, the refractive index of each optical member OPT-R, OPT-G, OPT-B, and OPT-NIR is set to be larger as the optical member corresponds to light having a longer wavelength.
In the seventh embodiment, the refractive index ORF-NIR of the optical member OPT-NIR corresponding to the microlens MCL-NIR for near-infrared (NIR) light having the longest wavelength is set to the maximum, and the wavelength is set to 2. The refractive index ORF-R of the optical member OPT-R corresponding to the microlens MCL-R for the longest red (R) light is set to the second largest, and the wavelength is the third longest for the green (R) light. Optical member corresponding to microlens MCL-G The refractive index ORF-G of OPT-G is set to the third highest, and the optical member corresponding to microlens MCL-B for blue (B) light having the fourth longest wavelength. The refractive index ORF-B of OPT-B is set to the fourth largest.
That is, the refractive indexes of each optical member OPT-R, OPT-G, OPT-B, and OPT-NIR are adjusted so as to have the relationship of ORF-NIR>ORF-R>ORF-G> ORF-B. ..

In the seventh embodiment, each microlens MCL-R, MCL-G, MCL-B, MCL-NIR, a color filter, an optical member OPT-R, OPT-G, OPT-B, and OPT-NIR are transmitted. The incident light is individually generated on the first surface 251 side of the substrate 250 for each of the corresponding red (R) pixel PXL11, green (Gr) pixel PXL12, blue (B) pixel PXL21, and near-infrared (NIR) pixel PXL22. Moreover, it is uniformly irradiated, and unnecessary incidents on the photodiode PD, which is not in charge, are greatly reduced.
Therefore, the crosstalk between pixels is significantly reduced, and the deterioration of the underground response is prevented.

As described above, according to the seventh embodiment, the same effect as that of the first embodiment described above can be obtained.

(8th Embodiment)
FIG. 15 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in the solid-state image sensor according to the eighth embodiment of the present invention.

The difference between the eighth embodiment and the seventh embodiment is as follows.
The unit pixel group 200G of the eighth embodiment is a light-shielding film SLD11-R that shields the light incident optical path by almost half in the flat film 240 on the first substrate surface 251 side of the photodiodes PD11, PD12, PD21, PD22. , SLD12-G, SLD21-B, and SLD22-NIR are arranged and configured to have a phase detection function.

According to the eighth embodiment, similar to the effect of the seventh embodiment described above, it is possible to reduce the crosstalk between pixels and prevent the angle response from deteriorating. Moreover, it is possible to obtain a sufficient phase difference detection function for any pixel without depending on the wavelength of the incident light.

(9th embodiment)
FIG. 16 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in the solid-state image sensor according to the ninth embodiment of the present invention.

The differences between the ninth embodiment and the seventh embodiment are as follows.
The unit pixel group 200H of the ninth embodiment is formed so that the photodiodes PD11, PD12, PD21, and PD22 are each divided into two, and are configured to have a phase detection function.
The photodiode PD11 is divided into two photodiodes PD11L and PD11R, the photodiode PD12 is divided into two photodiodes PD12L and PD12R, the photodiode PD21 is divided into two photodiodes PD21L and PD21R, and the photodiode PD22 is 2. It is divided into two photodiodes PD22L and PD22R.

According to the ninth embodiment, it is possible to reduce the crosstalk between pixels and prevent the angle response from deteriorating, as in the effect of the seventh embodiment described above. Moreover, it is possible to obtain a sufficient phase difference detection function for any pixel without depending on the wavelength of the incident light.

(10th Embodiment)
FIG. 17 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in the solid-state image sensor according to the tenth embodiment of the present invention.

The tenth embodiment differs from the first embodiment as follows.
In the unit pixel group 200I of the tenth embodiment, instead of adjusting the thickness of each microlens so that the light transmitted through the microlenses has a uniform focal length on one surface side of the plurality of photoelectric conversion units. , The refractive index of each microlens MCL-R, MCL-G, MCL-B, MCL-NIR is adjusted.

In the tenth embodiment, the refractive index of each of the microlenses MCL-R, MCL-G, MCL-B, and MCL-NIR is set to be larger as the microlens corresponds to light having a longer wavelength.
In the tenth embodiment, the refraction coefficient MRF-NIR of the microlens MCL-NIR for near-infrared (NIR) light having the longest wavelength is set to be the largest, and the red (R) light having the second longest wavelength is set. The refraction coefficient MRF-R of the microlens MCL-R for use is set to the second largest, and the refraction coefficient MRF-G of the microlens MCL-G for green (R) light having the third longest wavelength is the third highest. The refraction coefficient MRF-B of the microlens MCL-B for blue (B) light, which is set and has the fourth longest wavelength, is set to the fourth largest.
That is, the refractive indexes of the microlenses MCL-R, MCL-G, MCL-B, and MCL-NIR are adjusted so as to have the relationship of MRF-NIR>MRF-R>MRF-G> MRF-B. ..

In the tenth embodiment, the incident light transmitted through each of the microlenses MCL-R, MCL-G, MCL-B, and MCL-NIR is the corresponding red (R) pixel PXL11, green (Gr) pixel PXL12, and the like. For each of the blue (B) pixel PXL21 and the near-infrared (NIR) pixel PXL22, the first surface 251 side of the substrate 250 is individually and uniformly irradiated, and unnecessary incidents on the photodiode PD, which is not in charge, are significantly increased. Decrease.
Therefore, the crosstalk between pixels is significantly reduced, and the deterioration of the underground response is prevented.

As described above, according to the tenth embodiment, the same effect as that of the first embodiment described above can be obtained.

(11th Embodiment)
FIG. 18 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in the solid-state image sensor according to the eleventh embodiment of the present invention.

The eleventh embodiment differs from the tenth embodiment as follows.
The unit pixel group 200J of the eleventh embodiment is a light-shielding film SLD11-R that shields the light incident optical path by almost half in the flat film 240 on the first substrate surface 251 side of the photodiodes PD11, PD12, PD21, PD22. , SLD12-G, SLD21-B, and SLD22-NIR are arranged and configured to have a phase detection function.

According to the eleventh embodiment, it is possible to reduce the crosstalk between pixels and prevent the underground response from deteriorating, as in the effect of the tenth embodiment described above. Moreover, it is possible to obtain a sufficient phase difference detection function for any pixel without depending on the wavelength of the incident light.

(12th Embodiment)
FIG. 19 is a simplified cross-sectional view schematically showing a configuration example of a unit pixel group in the solid-state image sensor according to the twelfth embodiment of the present invention.

The twelfth embodiment differs from the tenth embodiment as follows.
The unit pixel group 200K of the twelfth embodiment is formed so that the photodiodes PD11, PD12, PD21, and PD22 are each divided into two, and are configured to have a phase detection function.
The photodiode PD11 is divided into two photodiodes PD11L and PD11R, the photodiode PD12 is divided into two photodiodes PD12L and PD12R, the photodiode PD21 is divided into two photodiodes PD21L and PD21R, and the photodiode PD22 is 2. It is divided into two photodiodes PD22L and PD22R.

According to the twelfth embodiment, it is possible to reduce the crosstalk between pixels and prevent the angle response from deteriorating, as in the effect of the tenth embodiment described above. Moreover, it is possible to obtain a sufficient phase difference detection function for any pixel without depending on the wavelength of the incident light.

The solid-state imaging device 10 described above can be applied as an imaging device to electronic devices such as digital cameras, video cameras, portable terminals, surveillance cameras, and medical endoscope cameras.

FIG. 20 is a diagram showing an example of the configuration of an electronic device equipped with a camera system to which the solid-state image sensor according to the embodiment of the present invention is applied.

As shown in FIG. 20, the electronic device 100 has a CMOS image sensor 110 to which the solid-state image sensor 10 according to the present embodiment can be applied.
Further, the electronic device 100 has an optical system (lens or the like) 120 that guides incident light (images a subject image) to the pixel region of the CMOS image sensor 110.
The electronic device 100 includes a signal processing circuit (PRC) 130 that processes the output signal of the CMOS image sensor 110.

The signal processing circuit 130 performs predetermined signal processing on the output signal of the CMOS image sensor 110.
The image signal processed by the signal processing circuit 130 can be displayed as a moving image on a monitor including a liquid crystal display or output to a printer, and can be directly recorded on a recording medium such as a memory card. Is possible.

As described above, by mounting the above-mentioned solid-state image sensor 10 as the CMOS image sensor 110, it is possible to provide a high-performance, compact, and low-cost camera system.
Electronic devices such as surveillance cameras and medical endoscope cameras are used in applications where there are restrictions on camera installation requirements such as mounting size, number of connectable cables, cable length, and installation height. Can be realized.

10 ... Solid-state image sensor, 20 ... Pixel unit, PXL11, PXL12, PXL21, PXL22 ... Pixel, PD11, PD12, PD21, PD22 ... Photodiode, 200, 200A-200K ... Unit pixel Group, 210 ... Microlens array, MCL-R, MCL-G, MCL-B, MCL-NIR ... Microlens, 220 ... Color filter array, 230 ... Photodiode array, 240 ... Flat layer, 250 ... semiconductor substrate, OPT-R, OPT-G, OPT-B, OPT-NIR ... optical member, 30 ... vertical scanning circuit, 40 ... horizontal scanning circuit, 50. Read circuit, 60 ... Timing control circuit, 70 ... Read unit 100 ... Electronic device, 110 ... CMOS image sensor, 120 ... Optical system, 130 ... Signal processing circuit (PRC) ).

Claims (12)

It has a pixel unit in which a unit pixel group including a plurality of color pixels for photoelectric conversion is arranged.
The unit pixel group is
It has a function of photoelectrically converting light incident from one side, and has a plurality of photoelectric conversion units corresponding to the plurality of colors.
A lens unit in which a plurality of lenses whose focal length depends on a wavelength, which incidents light on the plurality of photoelectric conversion units, are arranged.
The lens unit is adjusted so that the light transmitted through the plurality of lenses has a uniform focal length on the one surface side of the plurality of photoelectric conversion units .
The plurality of photoelectric conversion units are each divided in a direction parallel to the one surface.
A solid-state image sensor with a phase difference detection function. The lens part is
The solid-state image pickup device according to claim 1 , wherein the thickness of each lens is changed so that the light transmitted through the lenses has a uniform focal length on the one side of the plurality of photoelectric conversion units. The solid-state image sensor according to claim 2, wherein the thickness of each lens is set to be thicker as the lens corresponds to light having a longer wavelength. The lens part is
Claims that the height of each lens from one side of the photoelectric conversion unit is changed so that the light transmitted through the lens has a uniform focal length on the one surface side of the plurality of photoelectric conversion units. 1. The solid-state imaging device according to 1. The solid-state image sensor according to claim 4 , wherein the height of each lens from one side of the photoelectric conversion unit is set higher as the lens corresponds to light having a longer wavelength. The lens part is
The solid according to claim 1, which includes an optical member arranged between the light emitting side of each lens and one surface side of the photoelectric conversion unit and guiding the light transmitted through the lens to the one surface side of the plurality of photoelectric conversion units. Image sensor. Before Symbol light Faculty materials, as optical members wavelength corresponding to a long optical, solid-state imaging device according to claim 6, wherein the refractive index is set larger. The lens part is
The solid-state imaging device according to claim 1 , wherein the refractive index of each lens is changed so that the light transmitted through the lens has a uniform focal length on the one side of the plurality of photoelectric conversion units. The solid-state image sensor according to claim 8 , wherein each lens has a higher refractive index as a lens corresponding to light having a longer wavelength. It has a filter array including a plurality of color filters arranged between the light emitting side of each lens of the lens unit and one surface side of the photoelectric conversion unit.
The filter array is
It is divided into a red filter area, a green filter area, a blue filter area, and an infrared area.
The plurality of photoelectric conversion units are
Red photoelectric conversion unit corresponding to the red filter region, a green photoelectric conversion unit corresponding to the green filter region, the blue photoelectric conversion unit corresponding to the blue filter region, and the infrared photoelectric conversion units corresponding to the infrared region The solid-state imaging device according to any one of claims 1 to 9, which includes. It has a pixel unit in which a unit pixel group including a plurality of color pixels for photoelectric conversion is arranged.
The unit pixel group is
With multiple photoelectric conversion units,
A method for manufacturing a solid-state image sensor in which the pixels are formed including a lens portion in which a plurality of lenses are arranged.
As a step of forming the unit pixel group,
A step of forming a plurality of photoelectric conversion units corresponding to the plurality of colors having a function of photoelectrically converting light incident from one surface side.
A step of forming a lens portion in which a plurality of lenses whose focal length depends on a wavelength, which incidents light on the plurality of photoelectric conversion portions , is included.
In the step of forming the photoelectric conversion unit,
The plurality of photoelectric conversion units are each divided in a direction parallel to the one surface.
With a phase difference detection function,
In the process of forming the lens portion,
A method for manufacturing a solid-state image sensor that adjusts light transmitted through a plurality of lenses so that the light transmitted through the plurality of lenses has a uniform focal length on the one side of the plurality of photoelectric conversion units. With a solid-state image sensor,
The solid-state image sensor has an optical system for forming a subject image, and the solid-state image sensor has an optical system.
The solid-state image sensor
It has a pixel unit in which a unit pixel group including a plurality of color pixels for photoelectric conversion is arranged.
The unit pixel group is
It has a function of photoelectrically converting light incident from one surface side, and has a plurality of photoelectric conversion units corresponding to the plurality of colors.
A lens unit in which a plurality of lenses whose focal length depends on a wavelength, which incidents light on the plurality of photoelectric conversion units, are arranged.
The lens unit is adjusted so that the light transmitted through the plurality of lenses has a uniform focal length on the one side of the plurality of photoelectric conversion units .
The plurality of photoelectric conversion units are each divided in a direction parallel to the one surface.
An electronic device that has a phase difference detection function.

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