JP2884195B2 - Solid-state imaging device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state imaging device having an exposure detecting means.

[0002]

2. Description of the Related Art Conventionally, solid-state imaging devices have been used in various fields such as movies, electronic cameras, AF sensors, and the like. Accordingly, it is necessary to control the aperture, shutter speed (light integration time), and the like. Therefore, in a solid-state imaging device used for a movie or the like, the output of the previous frame is fed back to control the exposure. In an electronic camera, an exposure amount is temporarily stored and an image is captured.

[0003]

However, in a system in which the exposure is controlled by feeding back the output of the previous frame, the ability to follow a sudden change in brightness is poor or the light source fluctuates in an AC manner. In some cases, flicker occurs. Also, the method of once storing the exposure amount and taking an image cannot respond to a sudden change in brightness, flash photography, or the like.

For this reason, a method of providing a photometric photodiode on a transfer path (Japanese Patent Laid-Open No. 62-251395) has been proposed as an interline type CCD image pickup apparatus. It can be applied only to an image pickup apparatus, and has a problem that the number of new steps increases in a process.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems in a conventional solid-state imaging device having an exposure detecting means, and does not require a new process step, and is capable of instantaneously responding to a change in brightness. It is an object of the present invention to provide a solid-state imaging device provided with an exposure detecting means capable of coping with the above.

[0006]

In order to solve the above-mentioned problems, the present invention provides a photodiode comprising a semiconductor substrate having a substrate electrode on the back surface and a diffusion layer of a conductivity type opposite to the substrate. And the electrons generated by light incidence
In the solid-state imaging device of the type in which one of the carriers composed of hole pairs flows to the substrate side and the other carrier is accumulated in the diffusion layer, one of the carriers generated by light incident on the substrate side is passed through the substrate electrode. It is provided with an exposure detecting means for detecting and making exposure information.

In the solid-state imaging device thus configured, when light is incident, electron-hole pairs are generated, one carrier is accumulated in the diffusion layer, and the other carrier flows out through the substrate electrode. The current is detected by the exposure detecting means. Since this current is proportional to an electron-hole pair generated by light incidence, exposure information instantaneously corresponding to the amount of incident light can be obtained.

[0008]

Next, an embodiment will be described. FIG. 1 is a sectional view showing a basic embodiment of a solid-state imaging device according to the present invention. In the figure, reference numeral 1 denotes a p-type semiconductor substrate, and the substrate 1 is grounded via an exposure detecting means 5 connected to a substrate electrode 4. On the surface of the substrate 1, an n-type diffusion layer 2 for forming a photodiode for a pixel of an imaging device;
A p-type diffusion layer 3 for electrically separating pixels is formed.

Next, the light integration operation in the solid-state imaging device having such a configuration will be described. Usually, the p-type substrate 1 and n
In order to perform light integration, the photodiode 6 composed of the diffusion layer 2 has a power supply 8 through a switch 7 as shown in FIG.
Is connected and reset. When the switch 7 is turned on, the anode side of the photodiode 6 is reset to a positive potential, and the photodiode 6 enters a reverse bias state.
Next, when the switch 7 is turned off, light integration starts. When light enters as shown in FIG. 1, electron-hole pairs are generated. Then the n-type diffusion layer 2 is biased positively in the initial state, the electrons accumulate toward the n-type diffusion layer 2, a hole flows out through the substrate electrode 4 of the substrate 1, the current I _P Occur. This current _IP is caused by electrons generated by light incidence.
It is proportional to the hole pair. Therefore, by detecting this current _IP by the exposure detecting means 5, it is possible to obtain information on the average brightness of the entire light receiving surface (exposure information).

Next, FIG. 3 shows a specific embodiment in which the present invention is applied to a CCD solid-state imaging device having a pn junction type photodiode. In the figure, 11 is a p-type substrate, 12 is an n-type diffusion layer for forming a photodiode for pixels, 13
Is a p-type channel stop diffusion layer for separating pixels, 14 is a transfer CCD, and 15 is a control electrode of the transfer CCD 14. A light-shielding film 16 is provided on the surface of the transfer CCD 14, so that light is incident only on the pn junction type photodiode portion.

In such a CCD type solid-state imaging device, the substrate electrode 17 formed on the back surface of the substrate for obtaining the potential of the substrate 11 is electrically connected to the chip mounting surface of the package of the imaging device. It is connected to one of the output pins of the package. This terminal is usually connected to a power supply or ground to give a substrate potential,
In the present invention, the current-voltage conversion amplifier 21 is connected to the current-voltage conversion amplifier 21 to detect a current value, and the current-voltage conversion amplifier 21 constitutes an exposure detection unit. In the current-voltage conversion amplifier 21, the substrate electrode 17 is connected to the negative terminal, and the negative terminal is given the same potential as the positive terminal by virtual grounding. Therefore, an output voltage V _OUT expressed by the following equation (1) appears at the output terminal 22. V _OUT = V _SUB- (I _P + I _OF ) · _RL (1) where V _SUB is a substrate voltage, I _P is a photocurrent corresponding to the amount of incident light, and I _OF is a photocurrent. Offset current that flows even in the dark,
R _L is a feedback resistor of the current-voltage conversion amplifier 21. As can be seen from the above equation (1), the output voltage V _OUT is equal to the photocurrent I.
Proportional to _P, and because the light current I _P is proportional to the amount of incident light, Ararewaru information of the incident light quantity is the output voltage V _OUT. When the offset current I _OF is sufficiently smaller than the photocurrent I _P , it is approximated by the following equation (2). _{V OUT ≒ V SUB -I P ·} R L ······ (2)

FIG. 4 shows the relationship between the brightness and the output voltage V _OUT when V _SUB = 0 under such conditions. It can be seen that the output voltage V _OUT fluctuates to the negative side following the temporal change in brightness, and that this output voltage represents exposure information that follows the change in brightness.

Further, instead of the current-voltage conversion amplifier 21,
By using the current-to-voltage conversion amplifier 23 in which the diode D is inserted in the feedback circuit shown in FIG. 5, a logarithmically compressed output voltage V _OUT can be obtained.

Next, in a still camera or the like, an example of the construction of an exposure detecting means provided with an integration circuit necessary for performing direct photometry for stopping the light integration operation when a predetermined exposure amount is reached while taking an image is shown in FIG. Shown in This exposure detection means
24 is a capacitor C and a MOS in the feedback circuit of the current-voltage conversion amplifier.
This is a circuit in which a parallel circuit of the transistor 25 is inserted. By replacing this with the current-voltage conversion amplifier 21 shown in FIG. 3, an integration operation is performed. That is, when the gate application pulse φ _IR of the feedback MOS transistor 25 is set to the H level, the MOS transistor 25 is turned on and the feedback capacitance C is reset. When φ _{IR is set} to L level from this state, the MOS transistor 25 is turned off and the integration operation is started. FIG. 7 shows an exposure detecting means 24 for a change in brightness.
5 shows a temporal change of the output voltage V _OUT of FIG. In the illustrated example, when t = 0, φ _IR is changed from H level to L level. As can be seen from FIG. 7, the exposure detecting means 24 integrates the current generated corresponding to the brightness, and simultaneously sets the integration start time of each pixel of the image sensor and the integration start time of the exposure detection means 24. if, since the average level and the output voltage V _OUT of the integrated amount of each pixel corresponding, the output voltage V _OUT
, An appropriate exposure can be determined.

The above-described configuration example of the exposure detecting means has been described in the case where the offset current I _OF can be ignored. However, when the offset current I _OF is large, the exposure detecting accuracy is corrected by the following means. Can be raised.

(1) First, in a system configuration in which the output voltage V _OUT is used by A / D conversion, the output in the dark is A / D converted in advance, and the digitized data is stored in a memory. In addition, the output voltage can be corrected by performing digital operation processing.

(2) The current can be corrected by performing current-voltage conversion after subtracting the same current as the offset current I _{OF in the} dark from the photocurrent. FIG. 8 shows this type of exposure detection means. This exposure detecting means is constructed by connecting a variable current source 26 composed of a variable resistor R _C and a pair of current mirrors to a negative input terminal of a current-voltage conversion amplifier, and when dark, V _OUT = 0V By adjusting the variable resistor R _C so that the offset current I
_OF can be canceled.

In order to electrically perform the adjustment, there is a method of connecting a current output type D / A converter to a current-voltage conversion amplifier. One example is shown in FIG. In this configuration example, a 4-bit current output type D / A converter 27 is connected, but D _{0 is set} so that V _OUT = 0 V in the dark.
By adjusting the data · · · D _3, it is possible to cancel the offset current I _OF.

By connecting the variable current source 26 and the current output type D / A converter 27 shown in FIGS. 8 and 9 to the current-voltage conversion amplifier shown in FIGS. The accuracy of the exposure information can be improved by canceling the current I _OF .

In the above embodiment, average exposure information of the entire light receiving surface of the CCD type solid-state imaging device can be obtained.
If the light-receiving surface can be divided into several blocks and the exposure can be determined by weighting each block,
More effective. This can be realized by dividing the substrate electrode provided on the back surface of the substrate into several blocks and extracting photocurrent.

FIG. 10 shows an example of a metal pattern of a package in which the electrodes on the chip mounting surface of the solid-state imaging device for detecting the exposure are divided into several blocks. This configuration example is a 14-pin package, and 31-1, 31-2,... 31-14 represent each pin. The solid-state imaging device is mounted with its imaging surface 32 aligned with the position shown by the broken line, and pins 31-1, 31-7,
31-8, 31-11, and 31-14 are connected to the current-voltage conversion amplifiers 21 or 23 shown in FIG. 3 or FIG. 5 or the exposure detecting means 24 shown in FIG. Upper right,
Exposure information corresponding to the upper left, lower left, center, and lower right can be obtained. However, since the light receiving area of each block differs due to a shift in the chip mounting position or the like, it is necessary to adjust the output gain for each block in advance by applying average light. This can be dealt with by various methods such as adjustment using a trimmer or the like, or writing the correction coefficient for each block into the ROM for each chip and adjusting using the data.

Although a specific embodiment applied to the CCD type solid-state imaging device shown in FIG. 3 has been described above, the present invention relates to a solid-state imaging device using SIT as pixels as shown in FIG. As shown in FIG. 12, the present invention can also be applied to a solid-state imaging device using BASIS as a pixel, and the polarity is reversed, but the photocurrent IP flowing to the substrate electrode is similarly _transmitted from a current-voltage conversion amplifier or the like. The exposure information can be obtained by detecting the exposure information.

Further, the substrate 35 and the channel / stop region 36 are electrically connected to the solid-state imaging device having a MOS type photodiode as shown in FIG. 13 instead of the pn junction type photodiode. The present invention can be applied to such a structure, and the exposure can be controlled by detecting the substrate current. In FIG. 13, 37 is
An SiO ₂ film 38 indicates a polysilicon gate.

Next, as in a CCD type solid-state image pickup device having a vertical overflow drain structure, the other of the electron-hole pairs generated by photoelectric conversion, which is not a carrier for pixel accumulation, does not flow to the substrate side. An embodiment in which the present invention is applied to an imaging device will be described.

FIG. 14 shows an embodiment applied to a CCD type solid-state imaging device having a vertical overflow drain structure. FIG.
The same reference numerals are given to the same or equivalent components as those of the embodiment shown in FIG. The difference from the embodiment shown in FIG. 3 is that the substrate 11 is n-type and the p-type epitaxial layer 41 is formed thereon. Therefore, the substrate 11
Must be biased to a positive potential, and the potential of the epitaxial layer 41 must be the ground potential. Therefore, a potential is applied through the channel stop diffusion region 13 having a high concentration.
Also, an n-type diffusion layer constituting a photodiode for photoelectric conversion
12 is biased to have a positive potential at the time of reset.

When light is incident in such a state and an electron-hole pair is generated, electrons are accumulated in the n-type diffusion layer 12, and holes flow out through the channel-stop diffusion region 13 and a current I _P flows. Occurs. This current _IP is converted to a current-voltage conversion amplifier 21.
In the same manner as in the embodiment shown in FIG.
It is possible to obtain information on average brightness of the entire light receiving surface. Further, the current-voltage conversion amplifier 21 is connected to the current-voltage conversion amplifier shown in FIG.
By substituting the voltage conversion amplifier 23 or the exposure detecting means 24 shown in FIG. 6, it is also possible to obtain a logarithmic compressed output or an integrated output.

In the CCD type solid-state image pickup device having this structure, a part of the electrons generated by the light incidence flows out to the substrate, so that the channel stop diffusion region 13 is connected to GND in FIG. , + Terminal to V _SUB
It is also possible to obtain exposure information by connecting a current-to-voltage conversion amplifier to which a current is connected and detecting this current. However, this current is affected not only by the intensity of the incident light but also by the potential of the n-type diffusion layer. In particular, a large current flows immediately below the pixel at which the saturated level has been reached by the intense light. For this reason, the exposure control by this current is not an average photometry, but a form in which the weight is increased for bright pixels, and this method is effective depending on the application.

Next, a description will be given of an embodiment in which the imaging surface is divided into a plurality of blocks and the photocurrent is detected.
FIG. 15 shows a configuration example of an interline type CCD solid-state imaging device. A photodiode 51 constituting a pixel, a vertical CCD 52 for transferring charges, a horizontal CCD 53, a transfer gate 54 for transferring charges of the photodiode 51 to the vertical CCD 52, and a charge for detecting charges transferred by the horizontal CCD 53. It comprises a detection amplifier 55. In order to separate each pixel column, a channel stop diffusion region 56 is formed as shown by a broken line. By dividing the channel stop diffusion region 56 into a plurality of blocks according to the arrangement of the electrodes, exposure information can be obtained in block units.

FIG. 16 shows an example of the configuration. 61 in the figure
Is a column of channel stop diffusion regions, and 62 is an imaging surface. The imaging surface 62 is divided into three regions, left, center, and right, as shown in the figure, and electrodes for the channel stop diffusion region are separately provided for each of those regions. The current to the respective electrodes - is connected with a voltage conversion amplifier 21, when their output voltage is _{V 1, V 2, V 3} , V 1 is the left region, V ₂ is the central region, V ₃ is the right area brightness The output voltage corresponds to the output voltage. In this manner, by dividing the blocks into blocks according to the arrangement of the electrodes in the channel / stop diffusion region, brightness information for each block can be detected. Arbitrary block division can be realized by using a transparent electrode or the like to establish conduction with the channel / stop diffusion region near the center of the imaging surface. Also, by providing the current-voltage conversion amplifier 23 shown in FIG. 5 or the exposure detecting means 24 shown in FIG. 6 instead of the current-voltage conversion amplifier 21 in FIG. 16, it is also possible to obtain a logarithmic compression output, an integration output, and the like. It is.

In the above embodiment, the present invention is applied to a CCD type solid-state image pickup device having a vertical overflow drain structure. However, the present invention is not limited to the CCD type solid-state image pickup device having this structure. Forming layers, etc.
The carrier that does not accumulate in the pixel out of the electron-hole pairs generated by light incidence, such as the one with a structure in which a photodiode is formed in that part, is not transferred from the substrate electrode but to the channel / stop diffusion region, etc. The present invention can be applied to any solid-state imaging device of a type that flows out from electrodes.

As an example, FIG. 17 shows an embodiment applied to a solid-state image pickup device having a vertical overflow drain structure using a MOS photodiode as a pixel. In this embodiment, a p-type epitaxial layer is formed on an n-type substrate 71 to form a p-type well 72. The p-type well 72 is configured to be biased through the p ⁺ -type channel / stop diffusion region 73. 74 is a SiO ₂ film, 75
Is a polysilicon gate. In the solid-state imaging device having such a structure, when the light in a state of pulling up the gate voltage V _G applied to the polysilicon gate 75 to a positive potential is incident, electron-hole pairs are generated, the inversion layer of electrons is directly below the gate And holes flow out through the channel stop diffusion region 73. By detecting this current with the current-voltage conversion amplifier 21, an output corresponding to the brightness can be obtained as in each of the above embodiments.

As another embodiment of this type, CM
FIG. 18 shows a solid-state imaging device using a D (Charge Modulation Device) as a pixel. CMD is a low-concentration n-type epitaxial layer 82 stacked on a p-type substrate 81.
The source region 83 and drain region 84 made of n ⁺ diffusion layer formed, and a ring-shaped polysilicon gate 85 formed on the oxide film. The p-type substrate 81 has a substrate electrode 86
The substrate voltage V _SUB is _supplied through the _switch . The drain region 84 is fixed to the drain voltage V _D, source region 83 is given the ground potential is connected to a vertical signal line.

[0033] In this state, by controlling the gate voltage V _G, the reset operation, accumulating operation, and read operation is performed. Of these operations, the case of the accumulation operation will be described. During storage operation, the gate potential V _G is biased to a negative potential to the gate just below the inversion layer is formed. When light is incident in this state and an electron-hole pair is generated, holes are accumulated in the inversion layer immediately below the gate, and electrons flow out of those electrodes from the point where they are generated via the source region 83 or the drain region 84. . By detecting the current flowing from the electrode through the drain region 84 by the current-voltage conversion amplifier 21, the brightness information of the light receiving surface of the imaging device can be obtained.

In this embodiment, unlike the previous embodiments, the carrier opposite to the carrier accumulated in the pixel flows out into two regions, ie, a source region and a drain region, but is uniform in a small region of each pixel. If light strikes, even if the brightness changes, the ratio of the carriers flowing out of the source region and the drain region becomes constant, and the brightness can be detected as in the previous embodiments. Further, by replacing the current-voltage conversion amplifier 21 in this embodiment with the current-voltage conversion amplifier 23 shown in FIG. 5 or the exposure detecting means 24 shown in FIG. 6, a logarithmic compression output or an integral output can be obtained. Needless to say.

In the solid-state imaging device using the CMD, of the electron-hole pairs generated by the incidence of light, the holes generated in the light receiving portion near the gate are accumulated immediately below the gate. In addition to the above, for example, holes generated in the source region and the drain region have components flowing out to the substrate side. The substrate current generated by holes not accumulated immediately below the gate also corresponds to the amount of incident light. Therefore, even if this substrate current is detected by a current-voltage conversion amplifier as shown in the embodiment of FIG. 3, exposure information can be obtained similarly. That is, in FIG. 18, the drain voltage V _D is applied to the drain region 84, the substrate electrode 86, a current which is connected to V _SUB to the positive terminal -
By connecting a voltage conversion amplifier, it is possible to detect substrate current and obtain exposure information.

In each of the above embodiments, the description has been made assuming that the photocurrent due to carriers other than the photocurrent accumulated in the photodiode in the solid-state imaging device is used as the exposure information. Needless to say, it can be used as other information.

[0037]

As described above with reference to the embodiments,
According to the present invention, it is possible to realize a solid-state imaging device capable of obtaining exposure information instantaneously corresponding to the amount of incident light by providing a simple exposure detecting means without adding a new process or the like.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a basic embodiment of a solid-state imaging device according to the present invention.

FIG. 2 is a diagram showing an equivalent circuit for driving the embodiment shown in FIG.

FIG. 3 is a diagram showing an embodiment in which the present invention is applied to a CCD solid-state imaging device having a photodiode.

FIG. 4 is a diagram showing a relationship between brightness and an output voltage of an exposure detecting means in the embodiment shown in FIG.

FIG. 5 is a circuit diagram showing another example of the configuration of the exposure detecting means.

FIG. 6 is a circuit diagram showing still another example of the configuration of the exposure detecting means.

FIG. 7 is a diagram showing a relationship between brightness and a detection output voltage when the exposure detection means shown in FIG. 6 is used.

FIG. 8 is a circuit configuration diagram showing an exposure detection unit in which an offset current has been corrected.

FIG. 9 is a circuit diagram showing another example of the configuration of the exposure detecting means for correcting the offset current.

FIG. 10 is a diagram illustrating an example of a metal pattern of a package used in a solid-state imaging device for performing exposure detection for each block.

FIG. 11 is a diagram illustrating an embodiment in which the present invention is applied to a solid-state imaging device using SIT as pixels.

FIG. 12 is a diagram illustrating an embodiment in which the present invention is applied to a solid-state imaging device using BASIS as pixels.

FIG. 13 is a diagram illustrating an example in which the present invention is applied to a solid-state imaging device having a MOS photodiode.

FIG. 14 is a diagram illustrating an embodiment in which the present invention is applied to a CCD solid-state imaging device having a vertical overflow drain structure.

FIG. 15 is a diagram illustrating a configuration example of an interline CCD solid-state imaging device.

16 is a diagram illustrating a configuration example in a case of obtaining exposure information in block units in the device illustrated in FIG. 15;

FIG. 17 is a diagram showing an embodiment in which the present invention is applied to a solid-state imaging device having a vertical overflow drain structure using a MOS photodiode as a pixel.

FIG. 18 is a diagram illustrating an embodiment in which the present invention is applied to a solid-state imaging device using a CCD as a pixel.

[Explanation of symbols]

 Reference Signs List 1 p-type semiconductor substrate 2 n-type diffusion layer 3 p-type diffusion layer 4 substrate electrode 5 exposure detecting means 11 p-type substrate 12 n-type diffusion layer 13 p-type channel stop diffusion layer 14 transfer CCD 15 control electrode 16 light-shielding film 21 current -Voltage conversion amplifier

──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Hideaki Yoshida 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd. (56) References JP-A-2-149079 (JP, A) JP-A JP-A-63-143862 (JP, A) JP-A-63-90974 (JP, A) JP-A-3-214869 (JP, A) JP-A-2-108924 (JP, A) (58) Fields investigated (Int .Cl. ⁶ , DB name) H04N 5/335 H01L 27/14

Claims (12)

(57) [Claims] A semiconductor substrate having a substrate electrode on a back surface;
A photodiode composed of the substrate and a diffusion layer of the opposite conductivity type, wherein one of carriers composed of electron-hole pairs generated by light incidence flows to the substrate side, and the other carrier accumulates in the diffusion layer. A solid-state imaging device of the type described above, further comprising an exposure detecting means for detecting one carrier generated by light incident on the substrate side through the substrate electrode to obtain exposure information. 2. The apparatus according to claim 1, wherein said substrate electrode is divided into a plurality of blocks, and said exposure detecting means is connected to each of said divided substrate electrodes to detect exposure information for each block. The solid-state imaging device according to claim 1. 3. An epitaxial layer of a conductivity type opposite to the substrate formed on a semiconductor substrate having a substrate electrode on a back surface;
A plurality of photodiodes formed by the epitaxial layer and a diffusion layer of the opposite conductivity type, and a plurality of channel stop diffusion regions of the same conductivity type as the epitaxial layer formed between the plurality of photodiodes, One of the carriers composed of electron-hole pairs generated by light incidence is accumulated in the photodiode, and the other carrier flows out to the channel-stop diffusion region in a solid-state imaging device of a type that flows to the channel-stop diffusion region. A solid-state imaging device, comprising: an exposure detection unit that detects the other carrier as a current and generates exposure information. 4. The apparatus according to claim 1, wherein the plurality of channel stop diffusion regions are divided into a plurality of blocks, and the exposure detecting means is provided for each block to detect exposure information for each block. Item 3. The solid-state imaging device according to Item 3. 5. An epitaxial layer of a conductivity type opposite to the substrate formed on a semiconductor substrate having a substrate electrode on a back surface;
A plurality of photodiodes formed by the epitaxial layer and a diffusion layer of the opposite conductivity type, and a plurality of channel stop diffusion regions of the same conductivity type as the epitaxial layer formed between the plurality of photodiodes, In a solid-state imaging device of a type in which one of carriers formed of electron-hole pairs generated by light incidence is accumulated in the photodiode and a part of the carrier flows to the substrate, and the other carrier flows to the channel / stop diffusion region. A solid-state imaging device comprising: an exposure detecting unit that detects one carrier flowing through the substrate without being stored in the photodiode as current and uses the carrier as exposure information. 6. The apparatus according to claim 1, wherein said substrate electrode is divided into a plurality of blocks and said exposure detecting means is connected to each of said divided substrate electrodes to detect exposure information for each block. The solid-state imaging device according to claim 5. 7. A plurality of MOS photodiodes formed on a semiconductor substrate having a substrate electrode on a back surface, and
And a channel-stop diffusion region of the same conductivity type as the semiconductor substrate formed between the photodiodes. One of the carriers composed of electron-hole pairs generated by light incidence accumulates immediately below the gate of the MOS photodiode. And the other is a solid-state imaging device of the type that flows into the substrate or the channel stop diffusion region, and further includes an exposure detection unit that detects the other carrier that flows into the substrate or the channel stop diffusion region as a current and uses the carrier as exposure information. A solid-state imaging device characterized by the above-mentioned. 8. The apparatus according to claim 1, wherein the substrate electrode or the channel stop diffusion region is divided into a plurality of blocks, and the exposure detecting means is provided for each block to detect exposure information for each block. The solid-state imaging device according to claim 7. 9. An epitaxial layer of a conductivity type opposite to the substrate formed on a semiconductor substrate having a substrate electrode on a back surface,
A plurality of MOS photodiodes formed on the epitaxial layer, and a channel stop diffusion region of the same conductivity type as the epitaxial layer formed between the MOS photodiodes, wherein electrons and holes generated by light incidence are provided. In the solid-state imaging device of the type in which one of the pairs of carriers is accumulated directly below the gate of the MOS photodiode and the other carrier flows in the channel stop diffusion region, the other carrier flows in the channel stop diffusion region. A solid-state imaging device, comprising: an exposure detection unit that detects current and detects exposure information. 10. The apparatus according to claim 1, wherein the plurality of channel / stop diffusion regions are divided into a plurality of blocks, and the exposure detecting means is provided for each block to detect exposure information for each block. Item 10. The solid-state imaging device according to Item 9. 11. An epitaxial layer of a conductivity type opposite to the substrate formed on a semiconductor substrate having a substrate electrode on a back surface,
A plurality of MOS photodiodes formed on the epitaxial layer, and a channel stop diffusion region of the same conductivity type as the epitaxial layer formed between the MOS photodiodes, wherein electrons and holes generated by light incidence are provided. In a solid-state imaging device of the type in which one of the pair of carriers is stored immediately below the gate of the MOS photodiode and part of the carrier flows to the substrate, and the other carrier flows to the channel / stop diffusion region. A solid-state imaging device comprising: an exposure detecting unit that detects one carrier flowing through the substrate without being accumulated in the substrate as a current and generates exposure information. 12. The apparatus according to claim 1, wherein the substrate electrode is formed by dividing the substrate into a plurality of blocks, and the exposure detecting means is connected to each of the divided electrodes to detect exposure information for each block. 12. The solid-state imaging device according to claim 11.