JP2006013176A - Solid-state image pickup device and camera equipped therewith - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solid-state image pickup device which is reduced in number of horizontal pixels and can output a video signal of good quality at a high speed without generating moire nor a false signal. <P>SOLUTION: The solid-state image pickup device is equipped with an imaging part 140 having a plurality of photoelectric converters 100 and a vertical transfer 110 formed, a horizontal transfer 120, and a distribution transfer 130 arranged between the imaging part 140 and horizontal transfer 120. The distribution transfer 130 is equipped with a plurality of independent electrodes for controlling a read of signal charges from the vertical transfer 110 to the horizontal transfer 120 independently by columns, and wires connected to the independent electrodes are formed through the horizontal transfer 120. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a solid-state imaging device that converts received light into an electrical signal and outputs it as a video signal.

  Conventionally, a solid-state imaging device that converts received light into an electrical signal and outputs it as a video signal is known, and a camera such as a digital still camera that displays a video signal obtained from the solid-state imaging device as a still image is known. ing. In recent years, a camera using such a solid-state imaging device has been demanded to further improve image quality and function, and the density of image quality has been increasing.

In such a solid-state imaging device, in order to improve the output speed of the video signal, a driving method that reduces the number of pixels in the output video signal by thinning out pixels from which signal charges are read has been proposed. For example, in Patent Document 1, signal charges of two pixels (two pixels at both ends) excluding the central pixel in each block are mixed in a solid-state imaging device, with three pixels in the horizontal direction as one block, A driving method is disclosed in which the number of pixels in the horizontal direction in the output video signal from the solid-state imaging device is reduced by mixing the signal charge with the signal charge of one pixel at the center of the adjacent block.
Japanese Patent Laid-Open No. 11-234688

  However, when sampling at the normal 1/3 frequency by thinning out or the like, the high frequency component is folded back at the Nyquist frequency 1 / 3F, so the (2/3) F component is added to the DC component. In the solid-state imaging device according to the conventional driving method, as shown in g1 of the graph showing the horizontal spatial frequency response in FIG. As a result, there is a problem that the image quality of the output video signal deteriorates due to the occurrence of moire or the generation of a false signal.

  Therefore, in view of such problems, the present invention provides a small-sized and high-resolution solid-state imaging device capable of reducing the number of pixels in the horizontal direction and outputting high-quality video signals at high speed without causing moire or false signals. The purpose is to provide.

In view of the above circumstances, the present inventors have realized a solid-state imaging device capable of reducing the number of pixels in the horizontal direction, and capable of outputting a high-quality video signal at high speed without causing moire or false signals. (The technology described in Japanese Patent Application No. 2002-328868 has already been proposed, although it has not been published.)
FIG. 1A is a schematic configuration diagram of a solid-state imaging device disclosed in Japanese Patent Application No. 2002-328868. FIG. 1B is a diagram for controlling reading of signal charges from the pixel unit 300 to the horizontal transfer unit 120. It is a schematic block diagram of the distribution transfer part 130 which has an independent drive electrode in the column direction.

  As shown in FIG. 1A, the solid-state imaging device shown in the above Japanese Patent Application No. 2002-328868 is two-dimensionally arranged corresponding to pixels, and is red (R), green (G) and blue ( B) a plurality of photoelectric conversion units 100 each having three color filters disposed thereon, and a CCD (Charge Coupled Device) having drive electrodes V1 to V6, V3R, V3L, V5R and V5L, and a drive pulse φV1 ˜V6, φV3R, φV3L, φV5R, and φV5L are constituted by a plurality of vertical transfer units 110 that transfer signal charges generated by the photoelectric conversion unit 100 in the column direction in response to the application, and a CCD that includes the drive electrodes H1 and H2. A horizontal transfer unit 120 that transfers signal charges in the row direction in response to application of drive pulses φH1 and φH2, and a plurality of photoelectric conversion units 100 and vertical transfer units 110 are formed. An independent drive electrode is formed between the imaging unit (effective pixel unit) 140 and the horizontal transfer unit 120 and controls the readout of signal charges from the pixel unit 300 to the horizontal transfer unit 120 in the column direction. And the sorting / transferring unit 130.

  As shown in FIG. 1B, the vertical transfer unit 110 of the distribution transfer unit 130 has the same electrode structure for every 2n + 1 (n is an integer of 1 or more) columns, and drive pulses φV1 to φV6, φV3R, φV3L. , .Phi.V5R and .phi.V5L are applied to a CCD having drive electrodes V1 to V6, V3R, V3L, V5R and V5L. Here, the drive electrodes V1, V2, V4, and V6 are common electrodes over all the columns, and the drive electrodes V3, V3R, V3L, V5, V5R, and V5L are independent electrodes separated into islands in each column, and are distributed and transferred. The unit 130 controls reading of signal charges from the vertical transfer unit 110 to the horizontal transfer unit 120 independently for each column.

  In the solid-state imaging device having the above-described configuration, the driving pulses are applied to the vertical transfer unit 110, the horizontal transfer unit 120, and the distribution transfer unit 130 according to the timing chart shown in FIG. Are mixed with signal charges of three pixels. When drive pulses φV1 to φV6, φV3R, φV3L, φV5R, and φV5L are at a high level, the drive electrode to which the drive pulse is applied becomes a storage unit, and drive pulses φV1 to φV6, φV3R, φV3L, φV5R, and φV5L In the case of a high level, the drive electrode to which the drive pulse is applied becomes a barrier portion.

  According to the solid-state imaging device having the above-described configuration, since signal charges are not discarded in pixel mixing, a video signal with high sensitivity can be obtained. Further, since the center of gravity of each mixed pixel group has an equal interval in the horizontal transfer unit, the 2 / 3F component becomes 0 as shown in g2 of the graph showing the horizontal spatial frequency response in FIG. Is almost eliminated, and an image signal with little moire and false signals can be obtained.

  In the above description, the electrode structure having the same electrode structure with a cycle of 2n + 1 columns has been described. However, pixel mixing can be realized with a cycle of 2n (n is an integer of 1 or more) columns. However, moire and false signals become large.

However, in the solid-state imaging device, the distribution transfer unit 130 needs to include a plurality of independent drive electrodes.
The solid-state imaging device of the present invention is a solid-state imaging device including a pixel unit that generates signal charges and transfers the signal charges in the column direction, and a horizontal transfer unit that receives the signal charges from the pixel units and transfers them in the row direction. The pixel unit includes an effective pixel unit that generates a signal charge and a dummy pixel unit that does not generate a signal charge sandwiched between the effective pixel unit and the horizontal transfer unit, and the dummy pixel unit moves from the pixel unit to the horizontal transfer unit. A plurality of independent drive electrodes separated in the row direction for controlling the reading of the signal charges.

  As a result, the drive electrodes can be independently formed in the row direction in the dummy pixel portion that is not the effective pixel portion, so that the number of pixels in the horizontal direction is reduced by mixing pixels in the horizontal transfer portion without losing effective signal charges. In addition, it is possible to realize a solid-state imaging device that facilitates the realization of a solid-state imaging device that can output a high-quality video signal at high speed without generating moire or false signals.

  A first plug that vertically connects the drive electrode and a first wiring formed in a layer different from the drive electrode, and the drive electrode is disposed below the drive electrode layer below the first plug; The drive electrodes of different layers may be formed. As a result, the distance between the independent electrode and the wiring can be shortened, and the contact can be formed in a flat place, and the cost can be reduced by stabilizing the yield.

  In addition, there is a second plug that vertically connects the drive electrode and the second wiring formed in a layer different from the drive electrode, and the layer other than the drive electrode is provided below the drive electrode layer below the second plug. The drive electrode may not be formed.

  As a result, the dimensions required to form the contact between the independent electrode and the wiring can be determined only by the dimensional variation between the contact and the drive electrode, thereby minimizing the pixel size and reducing the size and height. A resolution solid-state imaging device can be realized.

Further, the present invention may be a camera including the solid-state imaging device according to any one of claims 1 to 3.
Thereby, since data is output from the solid-state imaging device at high speed, a camera capable of high-speed operation and excellent in image quality can be realized.

  According to the solid-state imaging device according to the present invention, signal charges are not discarded in pixel mixing, and the center of gravity of each mixed pixel group is equally spaced in the horizontal transfer unit, so that the number of pixels in the horizontal direction is reduced, and There is an effect that it is possible to realize a solid-state imaging device capable of outputting a high-quality video signal at high speed without generating moire or a false signal. Further, according to the solid-state imaging device according to the present invention, since the independent electrode can be formed without damaging the effective signal charge, the number of pixels in the horizontal direction is reduced without losing the effective signal charge, and There is an effect that it is possible to realize a solid-state imaging device capable of outputting a high-quality video signal at high speed without generating moire or false signals.

  Further, according to the solid-state imaging device according to the present invention, in the region where the independent electrode and the wiring are in contact, the contact can be stabilized and manufacturing variation can be prevented, so that damage such as yield is greatly reduced. There is an effect that a low-cost solid-state imaging device can be realized.

  Further, according to the solid-state imaging device according to the present invention, in the region where the independent electrode and the wiring are in contact with each other, the size necessary for forming the contact between the independent electrode and the wiring can be minimized. There is an effect that a small-sized and high-resolution solid-state imaging device can be realized.

  Therefore, according to the present invention, it is possible to provide a solid-state imaging device capable of reducing the number of pixels in the horizontal direction and outputting a high-quality video signal at high speed without generating moire or false signals, and has practical value. high.

(First embodiment)
Hereinafter, solid-state imaging devices according to embodiments of the present invention will be described with reference to the drawings.

  FIG. 1A is a schematic configuration diagram of the solid-state imaging device according to the first embodiment, and FIG. 1B is a row direction for controlling readout of signal charges from the pixel unit 300 to the horizontal transfer unit 120. FIG. 1C is a schematic configuration diagram of the distribution transfer unit 130 having independent drive electrodes, and FIG. 1C is a schematic cross-sectional view of the distribution transfer unit 130.

  The solid-state imaging device of the present embodiment is intended to realize a solid-state imaging device that can reduce the number of pixels in the horizontal direction and can output a high-quality video signal at high speed without causing moire or false signals. As shown in FIG. 1 (a), three color filters of red (R), green (G), and blue (B) are arranged in two dimensions corresponding to the pixels. And a plurality of photoelectric conversion units 100 and a CCD having drive electrodes V1 to V6, V3R, V3L, V5R, and V5L, and photoelectrically responding to application of drive pulses φV1 to φV6, φV3R, φV3L, φV5R, and φV5L. It is composed of a plurality of vertical transfer units 110 that transfer signal charges generated by the conversion unit 100 in the column direction, and a CCD having drive electrodes H1 and H2, and applies drive pulses φH1 and φH2. In accordance with the horizontal transfer unit 120 that transfers signal charges in the row direction, and between the image pickup unit (effective pixel unit) 140 and the horizontal transfer unit 120 in which a plurality of photoelectric conversion units 100 and vertical transfer units 110 are formed. The distribution transfer unit 130 is provided in a dummy pixel unit 125 which is provided and formed with independent drive electrodes separated in the row direction for controlling reading of signal charges to the horizontal transfer unit 120.

  As shown in FIG. 1B, the vertical transfer unit 110 of the distribution transfer unit 130 has the same electrode structure for every 2n + 1 (n is an integer of 1 or more) columns, and drive pulses φV1 to φV6, φV3R, φV3L. , .Phi.V5R and .phi.V5L are applied to a CCD having drive electrodes V1 to V6, V3R, V3L, V5R and V5L. Here, the drive electrodes V1, V2, V4, and V6 are common electrodes over all the columns, and the drive electrodes V3, V3R, V3L, V5, V5R, and V5L are independent electrodes separated into islands in each column, and are distributed and transferred. The unit 130 controls reading of signal charges from the vertical transfer unit 110 to the horizontal transfer unit 120 independently for each column.

  In addition, as shown in FIG. 1C, the distribution transfer unit 130 includes a drive electrode having a two-layer structure in which a first layer polysilicon 150 and a second layer polysilicon 160 are stacked, The first wiring 170, which is an aluminum layer that also serves as a light shield for the vertical transfer unit 110, the second wiring 180, which is a tungsten layer, and the first wiring 170 and the second-layer polysilicon 160 made of tungsten. Alternatively, a plug 190 that electrically connects the second wiring 180 is formed.

  In the solid-state imaging device having the above-described configuration, the driving pulses are applied to the vertical transfer unit 110, the horizontal transfer unit 120, and the distribution transfer unit 130 according to the timing chart shown in FIG. Are mixed with signal charges of three pixels. When drive pulses φV1 to φV6, φV3R, φV3L, φV5R, and φV5L are at a high level, the drive electrode to which the drive pulse is applied becomes a storage unit, and drive pulses φV1 to φV6, φV3R, φV3L, φV5R, and φV5L In the case of a high level, the drive electrode to which the drive pulse is applied becomes a barrier portion.

  FIG. 3 is a diagram showing an outline of the wiring layout of the solid-state imaging device according to the embodiment. The same elements as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof will be omitted here.

  As shown in FIG. 3, in the solid-state imaging device of the embodiment, the portion of the imaging unit (effective pixel unit) 140 excluding the photoelectric conversion unit 100 is covered with tungsten for light shielding, and the horizontal transfer unit 120 and the sorting transfer are performed. The unit 130 is covered with tungsten and aluminum for light shielding, and the horizontal transfer unit 120 is vertically connected to the independent electrodes V5, V5R and the pixel unit 300 including the imaging unit (effective pixel unit) 140 and the distribution transfer unit 130. A wiring layout is used in which wiring connected to V5L is formed and wiring connected to the independent electrodes V3, V3R, and V3L is formed in the horizontal direction from the side of the pixel portion 300.

  4 and 5 are diagrams showing details of the wiring layout of the distribution transfer unit 130, FIG. 4 shows the wiring layout of layers made of tungsten and aluminum, and FIG. 5 shows the wiring layout of layers made of polysilicon. Yes. 1 and 3 are denoted by the same reference numerals, and detailed description thereof will be omitted here.

  As shown in FIG. 4, in the distribution transfer unit 130, the vertical transfer unit 110 is covered with the first wiring 170 and the light shielding layer 400 that is a tungsten layer, and from the side of the pixel unit 300 (from the lower side or the upper side in the drawing). The second wiring 180 is wired, the second wiring 180 and the first wiring 170 are brought into contact with each other by a plug 190 at an appropriate position 410, and the first wiring 170 and the second-layer polysilicon 160 are further contacted. Are connected to the independent electrodes V3, V3R, and V3L by opening the light-shielding layer 400 at a predetermined position 420 and making contact with the plug 190, and are formed from the bottom of the pixel portion 300 (right side in the drawing). One wiring 170 is wired, and the light shielding layer 400 is opened at the position 420 between the first wiring 170 and the second-layer polysilicon 160, and the plug 190. Wiring layout is used to form a wiring which is connected to the independent electrodes V5, V5R and V5L by more contacts.

Further, the second wiring 180 is arranged so that the end portions thereof do not intersect with the driving electrodes (lower side or upper side in the drawing) overlapping with the second wiring 180 shown in FIG.
Further, as shown in FIG. 5, in the distribution transfer unit 130, the second-layer polysilicon 160 is formed on the vertical transfer unit 110, thereby forming the independent electrodes V3, V3R, V3L, V5, V5R, and V5L. Then, a wiring layout is used in which a common electrode is formed by forming the first layer of polysilicon 150 over the entire vertical transfer portion 110.

FIG. 6 is a diagram illustrating details of the wiring layout of the horizontal transfer unit 120.
As shown in FIG. 6, in the horizontal transfer unit 120, the horizontal transfer unit 120 is covered with the first wiring 170 and the light-shielding layer 600 that is a tungsten layer for light shielding, and below the horizontal transfer unit 120 (on the left side in the figure). The wiring layout for forming the first wiring 170 on the horizontal transfer unit 120 is used so that the first wiring 170 wired from (1) is brought into contact with the second layer polysilicon 160 at the position 420. Here, the light shielding layer 600 is arranged so as to fill the space of the wiring 170, but may be filled without a gap.

  FIG. 7A is a diagram showing details of the wiring layout (enlarged view of portion A in FIG. 5), and FIG. 7B is a detailed sectional view (cross section taken along the line cc ′ of FIG. 7A). 8A is a diagram showing details of the wiring layout (enlarged view of portion B in FIG. 5), and FIG. 8B is a detailed sectional view (d-- in FIG. 8A). It is sectional drawing in d 'line | wire.

  As shown in FIG. 7B, the distribution transfer unit 130 at the position 410 has a first layer polysilicon 150, a second layer polysilicon 160, a second wiring 180, and a second wiring. The plug 190 that contacts the first wiring 170 and the first wiring 170 and the first wiring 170 are sequentially stacked.

  Further, as shown in FIG. 8B, the distribution transfer unit 130 at the position 420, the first layer polysilicon 150, the second layer polysilicon 160, and the second layer polysilicon. The plug 190 that contacts the 160 and the first wiring 170 and the first wiring 170 are sequentially stacked.

Here, in each of the positions 410 and 420, the first-layer polysilicon 150 is located under the plug 190 and has a flat surface larger than the bottom area of the plug 190.
As described above, according to the solid-state imaging device of the present embodiment, the number of pixels in the horizontal direction can be reduced to 1 / (2n + 1) without discarding signal charges in pixel mixing without losing effective signal charges. In addition, the center of gravity of each mixed pixel group in the horizontal transfer unit 120 is equally spaced.
Therefore, the solid-state imaging device of the present embodiment can realize a solid-state imaging device capable of outputting a high-quality video signal at high speed without generating moire or a false signal.

  Further, according to the solid-state imaging device of the present embodiment, the wiring connected to the independent electrodes V5, V5R, and V5L is formed through the horizontal transfer unit 120 from the bottom of the pixel unit 300 in the vertical direction. Therefore, since the wiring connected to V5, V5R, and V5L can be formed regardless of the distance between the pixel portion and the horizontal transfer portion, the solid-state imaging device according to the present embodiment generates effective signal charges. To realize a solid-state imaging device wiring layout that facilitates the realization of a solid-state imaging device that can reduce the number of pixels in the horizontal direction without loss and can output high-quality video signals at high speed without generating moire or false signals Can do.

  In addition, according to the solid-state imaging device of the present embodiment, a part of the light shielding layer made of tungsten that has been conventionally used only for light shielding of the pixel unit 300 is connected to the independent electrodes V3, V3R, and V3L. Use as wiring. Therefore, since there is no need to provide a new layer and form a wiring for the independent electrodes V3, V3R, and V3L, the solid-state imaging device according to the present embodiment suppresses an increase in cost without adding a new manufacturing process. can do.

  Further, according to the solid-state imaging device of the present embodiment, the first wiring 170 serves not only as the wiring of the sorting and transferring unit 130 but also as a light shielding. Therefore, since the vertical transfer unit of the distribution transfer unit can be shielded by the first wiring, the solid-state imaging device according to the present embodiment prevents deterioration in image quality caused by light entering the vertical transfer unit 110. The solid-state imaging device can be realized.

  Further, according to the solid-state imaging device of the present embodiment, the independent electrode V <b> 5 that also serves as the light-shielding layer of the horizontal transfer unit 120 is used as the light-shielding layer made of aluminum that has been conventionally used only for light shielding of the horizontal transfer unit 120. , Used as wiring connected to V5R and V5L. Therefore, since there is no need to provide a new layer and form a wiring for the independent electrodes V5, V5R, and V5L, the solid-state imaging device of the present embodiment suppresses an increase in cost without adding a new manufacturing process. can do. Further, according to the solid-state imaging device of the present embodiment, the first layer polysilicon 150 has a larger area than the bottom surface of the plug 190 at the position 410 where the first wiring 170 and the second wiring 180 are in contact. The first-layer polysilicon 150 has a larger area than the bottom surface of the plug 190 at a position 420 where the first wiring 170 and the second-layer polysilicon 160 are in contact with each other. It has a flat surface. Therefore, the second wiring and the second-layer polysilicon have a flat surface with a larger area than the bottom surface of the plug, the distance to the wiring is shortened, the contact can be stabilized, and manufacturing variations are prevented. In addition, since the overlapping wiring and the end face of the drive electrode do not cross each other, they can be sufficiently electrically insulated, so that the solid-state imaging device of this embodiment greatly reduces damage such as yield and is low in cost. The effect that a solid-state imaging device can be realized.

  The contact with the polysilicon is the second-layer polysilicon 160, but the contact with the first-layer polysilicon 150 is the same, and the second-layer polysilicon 160 is larger than the bottom surface of the plug 190. What is necessary is just to have a flat surface in area.

  In the solid-state imaging device of this embodiment, the horizontal transfer unit 120 is shielded by the light shielding layer 600 that is a tungsten layer and the first wiring 170 that is an aluminum layer. However, the horizontal transfer unit may be formed of aluminum having a two-layer structure, and the horizontal transfer unit may be shielded from light by a light shielding layer that is an aluminum layer and a first wiring that is an aluminum layer.

  In the solid-state imaging device of the present embodiment, wirings connected to the independent electrodes V3, V3R, and V3L are formed by the first wiring 170 that is an aluminum layer and the second wiring 180 that is a tungsten layer. However, tungsten having a two-layer structure is formed on the distribution transfer portion, and wirings connected to the independent electrodes V3, V3R, and V3L are formed by the first wiring that is the tungsten layer and the second wiring that is the tungsten layer. May be.

  In addition, an on-chip lens layer may be formed on the horizontal transfer unit 120, or a black on-chip lens layer may be formed on the distribution transfer unit 130. Further, the black on-chip lens layer may be a lens layer close to black in which a plurality of colors are stacked, for example, R and B are stacked. At this time, the on-chip lens layer is formed, for example, in the process of forming the color film of the photoelectric conversion unit. As a result, it is possible to prevent the light from entering the transfer unit without adding a new manufacturing process, and thus it is possible to easily prevent the image quality from being deteriorated.

  Further, as shown in the top view of the horizontal transfer unit 120 in FIG. 9, the first transfer line 170 on the horizontal transfer unit 120 and the other line having a width larger than the first transfer line 170 may be A dummy wiring 900 having substantially the same shape as at least one of the one wiring 170 may be formed. As a result, the first wiring can be formed with high dimensional accuracy.

In the above-described embodiment, the electrode structure having the same electrode structure with a period of 2n + 1 columns has been described. However, pixel mixing can be realized with a period of 2n (n is an integer of 1 or more) columns.
The color filter has been described as an RGB three-color filter, but may be a four-color filter such as cyan, magenta, yellow, and green.
(Second Embodiment)
Hereinafter, a solid-state imaging device according to a second embodiment of the present invention will be described with reference to the drawings.

The schematic configuration of the solid-state imaging device in the second embodiment is the same as that of the solid-state imaging device in the first embodiment. Detailed descriptions of FIGS. 1A, 1B, and 1C are omitted here.
Further, the driving is the same as that of the solid-state imaging device according to the first embodiment in accordance with the timing chart shown in FIG.

  The outline of the wiring layout is the same as that of the solid-state imaging device according to the first embodiment and is shown in FIG. 4 and 10 are diagrams showing details of the wiring layout of the distribution transfer unit 130, FIG. 4 shows the wiring layout of layers made of tungsten and aluminum, and FIG. 10 shows the wiring layout of layers made of polysilicon. ing. 1 and 3 are denoted by the same reference numerals, and detailed description thereof will be omitted here.

FIG. 4 is the same as the solid-state imaging device according to the first embodiment, and a detailed description thereof will be omitted here.
Further, as shown in FIG. 10, in the distribution transfer unit 130, the second layer polysilicon 160 is formed on the vertical transfer unit 110, thereby forming the independent electrodes V3, V3R, V3L, V5, V5R, and V5L. Then, a wiring layout is used in which a common electrode is formed by forming the first layer of polysilicon 150 over the entire vertical transfer portion 110.

The details of the wiring layout of the horizontal transfer unit 120 are the same as those of the solid-state imaging device according to the first embodiment, and are shown in FIG.
FIG. 11A is a diagram showing details of the wiring layout (enlarged view of portion A in FIG. 10), and FIG. 11B is a detailed sectional view (cross section taken along the line cc ′ of FIG. 11A). 12A is a diagram showing details of the wiring layout (enlarged view of a portion B in FIG. 10), and FIG. 12B is a detailed sectional view (d-- in FIG. 12A). It is sectional drawing in d 'line | wire.

  As shown in FIG. 11B, the distribution transfer unit 130 transfers the second-layer polysilicon 160, the second wiring 180, the second wiring 180, and the first wiring 170 at the position 410. A plug 190 to be contacted and a first wiring 170 are sequentially stacked.

  Further, as shown in FIG. 12B, the distribution transfer unit 130 contacts the second layer polysilicon 160, the second layer polysilicon 160, and the first wiring 170 at the position 420. The plug 190 and the first wiring 170 are sequentially stacked.

  As described above, according to the solid-state imaging device of the present embodiment, the number of pixels in the horizontal direction can be reduced to 1 / (2n + 1) without discarding signal charges in pixel mixing without losing effective signal charges. In addition, the center of gravity of each mixed pixel group in the horizontal transfer unit 120 is equally spaced. Therefore, the solid-state imaging device of the present embodiment can realize a solid-state imaging device capable of outputting a high-quality video signal at high speed without generating moire or a false signal.

  Further, according to the solid-state imaging device of the present embodiment, the wiring connected to the independent electrodes V5, V5R, and V5L is formed through the horizontal transfer unit 120 from the bottom of the pixel unit 300 in the vertical direction. Therefore, since the wiring connected to V5, V5R, and V5L can be formed regardless of the distance between the pixel portion and the horizontal transfer portion, the solid-state imaging device according to the present embodiment generates effective signal charges. To realize a solid-state imaging device wiring layout that facilitates the realization of a solid-state imaging device that can reduce the number of pixels in the horizontal direction without loss and can output high-quality video signals at high speed without generating moire or false signals Can do.

  In addition, according to the solid-state imaging device of the present embodiment, a part of the light shielding layer made of tungsten that has been conventionally used only for light shielding of the pixel unit 300 is connected to the independent electrodes V3, V3R, and V3L. Use as wiring. Therefore, since there is no need to provide a new layer and form a wiring for the independent electrodes V3, V3R, and V3L, the solid-state imaging device according to the present embodiment suppresses an increase in cost without adding a new manufacturing process. can do.

  Further, according to the solid-state imaging device of the present embodiment, the first wiring 170 serves not only as the wiring of the sorting and transferring unit 130 but also as a light shielding. Therefore, since the vertical transfer unit of the distribution transfer unit can be shielded by the first wiring, the solid-state imaging device according to the present embodiment prevents deterioration in image quality caused by light entering the vertical transfer unit 110. The solid-state imaging device can be realized.

  Further, according to the solid-state imaging device of the present embodiment, the independent electrode V <b> 5 that also serves as the light-shielding layer of the horizontal transfer unit 120 is used as the light-shielding layer made of aluminum that has been conventionally used only for light shielding of the horizontal transfer unit 120. , Used as wiring connected to V5R and V5L. Therefore, since there is no need to provide a new layer and form a wiring for the independent electrodes V5, V5R, and V5L, the solid-state imaging device of the present embodiment suppresses an increase in cost without adding a new manufacturing process. can do. Further, according to the solid-state imaging device of the present embodiment, the first wiring 170 and the second-layer polysilicon 160 are in contact at the position 410 where the first wiring 170 and the second wiring 180 are in contact. At the position 420, the dimensions required for contact formation can be determined only by the dimensional variations of the plug 190 and the second-layer polysilicon 160, and can be kept to a minimum. The effect that can be realized. In addition, since the overlapping wiring and the end face of the drive electrode are arranged so as not to intersect with each other, it can be sufficiently electrically insulated. Therefore, the solid-state imaging device of the present embodiment can realize a low-cost solid-state imaging device. Is played.

  The contact with the polysilicon is the second-layer polysilicon 160, but the contact with the first-layer polysilicon 150 is also the same, and a drive electrode is arranged under the first-layer polysilicon 150. If there is no.

  In the solid-state imaging device of this embodiment, the horizontal transfer unit 120 is shielded by the light shielding layer 600 that is a tungsten layer and the first wiring 170 that is an aluminum layer. However, the horizontal transfer unit may be formed of aluminum having a two-layer structure, and the horizontal transfer unit may be shielded from light by a light shielding layer that is an aluminum layer and a first wiring that is an aluminum layer.

  In the solid-state imaging device of the present embodiment, wirings connected to the independent electrodes V3, V3R, and V3L are formed by the first wiring 170 that is an aluminum layer and the second wiring 180 that is a tungsten layer. However, tungsten having a two-layer structure is formed on the distribution transfer portion, and wirings connected to the independent electrodes V3, V3R, and V3L are formed by the first wiring that is the tungsten layer and the second wiring that is the tungsten layer. May be.

  In addition, an on-chip lens layer may be formed on the horizontal transfer unit 120, or a black on-chip lens layer may be formed on the distribution transfer unit 130. Further, the black on-chip lens layer may be a lens layer close to black in which a plurality of colors are stacked, for example, R and B are stacked. At this time, the on-chip lens layer is formed, for example, in the process of forming the color film of the photoelectric conversion unit. As a result, it is possible to prevent the light from entering the transfer unit without adding a new manufacturing process, and thus it is possible to easily prevent the image quality from being deteriorated.

  Further, as shown in the top view of the horizontal transfer unit 120 in FIG. 9, the first transfer line 170 on the horizontal transfer unit 120 and the other line having a width larger than the first transfer line 170 may be A dummy wiring 900 having substantially the same shape as at least one of the one wiring 170 may be formed. As a result, the first wiring can be formed with high dimensional accuracy.

In the above-described embodiment, the electrode structure having the same electrode structure with a period of 2n + 1 columns has been described. However, pixel mixing can be realized with a period of 2n (n is an integer of 1 or more) columns.
The color filter has been described as an RGB three-color filter, but may be a four-color filter such as cyan, magenta, yellow, and green.
(Third embodiment)
Hereinafter, a camera equipped with a solid-state imaging device according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 14 is a block diagram of a camera according to the third embodiment.
As shown in FIG. 14, the camera includes a lens 1000, a solid-state imaging device 1010, a drive circuit 1020, a signal processing unit 1030, and an external interface unit 1040.

In the camera having the above configuration, processing until a signal is output to the outside is performed in the following order.
(1) Light passes through the lens 1000 and enters the solid-state imaging device 1010.
(2) The signal processing unit 1030 drives the solid-state imaging device 1010 through the drive circuit 1020 and takes in an output signal from the solid-state imaging device 1010.
(3) The signal processed by the signal processing unit 1030 is output to the outside through the external interface unit 1040.

  As described above, according to the camera of the present embodiment, data is output from the solid-state imaging device at high speed. Therefore, the camera of this embodiment can realize a camera that can operate at high speed and has excellent image quality.

  The present invention can be used for a solid-state imaging device, and in particular, can be used for a digital still camera or the like.

(A) It is a schematic block diagram of the solid-state imaging device of the 1st and 2nd embodiment of this invention. (B) It is a schematic block diagram of the distribution transfer part 130 of the solid-state imaging device of 1st, 2nd embodiment.

(C) It is a schematic sectional drawing of the distribution transfer part 130 of the solid-state imaging device of 1st, 2nd embodiment.
It is an operation | movement timing chart in the case of performing pixel mixing of the solid-state imaging device of 1st, 2nd embodiment. It is a figure which shows the outline of the wiring layout of the solid-state imaging device of 1st, 2nd embodiment. It is a figure which shows the detail of the wiring layout of the layer which consists of tungsten and aluminum of the solid-state imaging device of 1st, 2 embodiment. It is a figure which shows the detail of the wiring layout of the layer which consists of polysilicon of the solid-state imaging device of 1st Embodiment. It is a figure which shows the detail of the wiring layout of the horizontal transfer part 120 of the solid-state imaging device of 1st, 2nd embodiment. (A) It is a figure (an enlarged view of the A section of FIG. 5) which shows the detail of the wiring layout of the distribution transfer part 130 of the solid-state imaging device of 1st Embodiment.

(B) It is detailed sectional drawing (sectional drawing in the cc 'line of Fig.7 (a)) of the distribution transfer part 130 of the solid-state imaging device of 1st Embodiment.
(A) It is a figure (detailed drawing of the B section of FIG. 5) which shows the detail of the wiring layout of the distribution transfer part 130 of the solid-state imaging device of 1st Embodiment.

(B) It is detailed sectional drawing (sectional drawing in the dd 'line of Fig.7 (a)) of the distribution transfer part 130 of the solid-state imaging device of 1st Embodiment.
It is a top view of the horizontal transfer part 120 of the solid-state imaging device of 1st and 2nd embodiment. It is a figure which shows the detail of the wiring layout of the layer which consists of polysilicon of the solid-state imaging device of 2nd Embodiment. (A) It is a figure which shows the detail of the wiring layout of the distribution transfer part 130 of the solid-state imaging device of 2nd Embodiment (enlarged view of the A section of FIG. 10).

FIG. 12B is a detailed cross-sectional view (cross-sectional view taken along the line cc ′ in FIG. 11A) of the distribution transfer unit 130 of the solid-state imaging device according to the first embodiment.
(A) It is a figure (enlarged view of the B section of FIG. 10) which shows the detail of the wiring layout of the distribution transfer part 130 of the solid-state imaging device of 1st Embodiment.

(B) It is detailed sectional drawing (sectional drawing in the dd 'line of Fig.11 (a)) of the distribution transfer part 130 of the solid-state imaging device of 1st Embodiment.
It is a block diagram of the camera of a 2nd embodiment. It is a graph which shows the horizontal spatial frequency response of the solid-state imaging device of 1st Embodiment. It is a figure which shows the outline of the wiring layout of the conventional solid-state imaging device.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Photoelectric conversion part 110 Vertical transfer part 120 Horizontal transfer part 125 Dummy pixel part 130 Distribution transfer part 140 Imaging part (effective pixel part)
150 First layer polysilicon 160 Second layer polysilicon 170 First wiring 180 Second wiring 190 Plug 300, 1200 Pixel portion 400, 600 Light shielding layer 410, 420 Position 900 Dummy wiring 1000 Lens 1010 Solid Imaging device 1020 Drive circuit 1030 Signal processing unit 1040 External interface

Claims (4)

A solid-state imaging device comprising: a pixel unit that generates a signal charge and transfers the signal charge in a column direction; and a horizontal transfer unit that receives the signal charge from the pixel unit and transfers the signal charge in a row direction.
The pixel unit includes an effective pixel unit that generates the signal charge, and a dummy pixel unit that does not generate the signal charge sandwiched between the effective pixel unit and the horizontal transfer unit, and the dummy pixel unit includes the pixel A solid-state imaging device comprising a plurality of independent drive electrodes separated in a row direction for controlling reading of signal charges from the unit to the horizontal transfer unit. A first plug that vertically connects the drive electrode and a first wiring formed in a different layer from the drive electrode;
2. The solid-state imaging device according to claim 1, wherein a drive electrode of a layer different from the drive electrode is formed below the drive electrode layer under the first plug. A second plug that vertically connects the drive electrode and a second wiring formed in a different layer from the drive electrode;
2. The solid-state imaging device according to claim 1, wherein no drive electrode other than the drive electrode is formed below the drive electrode layer under the second plug. A camera comprising the solid-state imaging device according to claim 1.

Images