JP5832414B2 - CHARGE COUPLED ELEMENT, ITS MANUFACTURING METHOD, ITS DRIVING METHOD, AND SOLID-STATE IMAGING DEVICE HAVING CHARGE COUPLED ELEMENT - Google Patents

Description

  The present invention relates to a charge coupled device (CCD), a manufacturing method thereof, a driving method thereof, and a solid-state imaging device including the charge coupled device.

  As a conventional CCD, for example, Patent Document 1 discloses a CCD having the following configuration. That is, as a constituent part of the photoelectric conversion unit, a plurality of first and second transfer electrodes made of polysilicon are formed in parallel on a semiconductor substrate via an insulating film. These first and second transfer electrodes are formed on one side of each other so that the second transfer electrode overlaps the first transfer electrode via an insulating film. Further, in the other side portion of the first and second transfer electrodes, a virtual electrode is formed on the surface portion of the semiconductor substrate in the gap region between the first transfer electrode and the second transfer electrode. Yes. The virtual electrode is formed by ion-implanting impurities of the same conductivity type as the semiconductor substrate using the first and second transfer electrodes as a mask.

  In the CCD configured as described above, by supplying clock pulses of H and L voltage levels to the first transfer electrode and the second transfer electrode, respectively, electrons excited in the photoelectric conversion period by light incident on the CCD are generated. The potential wells formed at the first, second and virtual electrode positions are transferred.

  For example, Patent Document 2 also discloses a CCD in which a light receiving portion is formed by ion implantation between the first and second transfer electrodes using these electrodes as a mask.

JP 60-165761 A Japanese Patent Laid-Open No. 4-207075

In the above-described CCD, a virtual electrode is formed between the first transfer electrode and the second transfer electrode. Therefore, in Patent Document 1, an insulating film between the first transfer electrode and the second transfer electrode exists at the first transfer electrode end on the virtual electrode side. Therefore, there is a problem that ion implantation into the virtual electrode is hindered by the insulating film. In addition, there is a problem that the formation position of the virtual electrode is shifted to either the first or second transfer electrode side due to the misalignment of the photolithography.
Further, in Patent Document 2, the first and second transfer electrodes are partially overlapped and formed in two layers, and the first and second transfer electrodes are removed by etching in a region including the two layer portions. For this reason, there is a problem that the surface of the semiconductor substrate after removal is not uniform, and the formation of virtual electrodes is hindered.
As described above, in the inventions of Patent Document 1 and Patent Document 2, a potential dip and a barrier are generated in the virtual electrode, causing a problem that the charge transfer efficiency of the charge coupled device is lowered.

  The present invention has been made to solve such a problem, and is a charge coupled device capable of improving charge transfer efficiency as compared with the prior art, a manufacturing method thereof, a driving method thereof, and a solid-state imaging device including the charge coupled device. An object is to provide an apparatus.

In order to achieve the above object, the present invention is configured as follows.
In other words, the charge coupled device according to one embodiment of the present invention includes a silicon substrate, a first transfer electrode formed on the gate insulating film over the silicon substrate at an interval, and an insulating film formed over the first transfer electrode. A charge coupled device comprising a second transfer electrode formed between the first transfer electrodes via the first virtual electrode and a second virtual electrode formed in the silicon substrate, wherein the charge coupled device includes A pair of first A transfer electrode and first B transfer electrode that separates the first transfer electrode in a direction perpendicular to the vertical direction for transferring the generated signal charge, that is, an opening extending in the horizontal direction, and the second transfer electrode A pair of second A transfer electrodes and second B transfer electrodes separated from each other, and in the vertical direction, the first A transfer electrode, the first virtual electrode, the first B transfer electrode, the second A transfer electrode, and the second virtual electrode; , Cycle of 2B transfer electrode in order Characterized in that repeatedly arranging the electrodes Te.

According to the charge coupled device of one embodiment of the present invention, the first transfer electrode and the second transfer electrode are separated from each other, and an opening between the separated first transfer electrodes and an opening between the separated second transfer electrodes are provided. Through which ions are implanted. Accordingly, a first virtual electrode is formed between the separated first transfer electrodes, and a second virtual electrode is formed between the separated second transfer electrodes. Thus, there is no conventional form in which the insulating film exists at the first transfer electrode end on the first virtual electrode side, and the ion implantation into the virtual electrode is not hindered by the insulating film.
Therefore, the potential dip and barrier in the virtual electrode can be reduced, and the charge transfer efficiency can be improved as compared with the conventional case.
Further, since the ions are implanted by self-alignment between the separated first transfer electrodes and between the separated second transfer electrodes, there is no bias in the formation position of the virtual electrodes.
Further, each opening for forming the first and second virtual electrodes is a portion where the single-layer first transfer electrode and second transfer electrode are separated from each other. As described above, since the transfer electrode is not a conventional form in which an opening is formed in a portion where two layers overlap each other, the surface from which the transfer electrode is removed by etching can be made uniform. Also from this point, the potential dip and barrier in the virtual electrode can be reduced, and the charge transfer efficiency can be improved as compared with the conventional case.

It is a perspective view which shows the solid-state imaging device in Embodiment 1 of this invention. It is a top view explaining the structure of the detector with which the solid-state imaging device shown in FIG. 1 is equipped. It is sectional drawing of the detector in arrow A-A 'shown to FIG. 2A. It is sectional drawing of the detector in arrow B-B 'shown to FIG. 2A. It is a figure which shows the two-phase clock pattern for driving the detector supplied to the solid-state imaging device shown in FIG. It is a figure which shows the connection relationship of the transfer electrode and two-phase clock terminal in the detector with which the solid-state imaging device shown in FIG. 1 is equipped. It is sectional drawing for demonstrating the manufacturing method of the detector part of the solid-state imaging device shown in FIG. It is a figure which shows the 4-phase clock pattern for driving the detector supplied to the solid-state imaging device shown in FIG. FIG. 2 is a potential diagram when a vertical CCD is driven by supplying four-phase clock pulses to the detector of the solid-state imaging device shown in FIG. 1. It is a figure which shows the connection relation of the transfer electrode and 4-phase clock terminal in the detector with which the solid-state imaging device shown in FIG. 1 is equipped. It is sectional drawing which shows the manufacturing method of the solid-state imaging device in Embodiment 2 of this invention.

  A charge coupled device, a manufacturing method thereof, a driving method thereof, and a solid-state imaging device including the charge coupled device according to an embodiment of the present invention will be described below with reference to the drawings. In each figure, the same or similar components are denoted by the same reference numerals. In addition, in order to avoid the following description from becoming unnecessarily redundant and to facilitate understanding by those skilled in the art, a detailed description of already well-known matters and a duplicate description of substantially the same configuration may be omitted. . Further, the contents of the following description and the accompanying drawings are not intended to limit the subject matter described in the claims.

Embodiment 1 FIG.
FIG. 1 shows a solid-state imaging device 300 according to a first embodiment of the present invention. The solid-state imaging device 300 is roughly divided into a detector array 501 in which a plurality of photodetectors 502 are arranged in a plurality of rows on a silicon substrate 301, and a photodetector 502 in the detector array 501 are sequentially selected. And a signal processing circuit 520 for reading out the signal charge generated in the photodetector 502 to the outside. 1 illustrates the case where the signal processing circuit 520 is formed on the silicon substrate 301, the present invention is not limited to this, and the signal processing circuit 520 may be provided separately.

  The detector array 501 includes a vertical CCD 509 that transfers signal charges generated by the photodetector 502 due to the internal photoelectric effect in the vertical direction 521 of the detector array 501, and further the signal charges transferred by the vertical CCD 509 of the detector array 501. A horizontal CCD 510 for transferring in the horizontal direction 522 and an output amplifier 508 for converting the transferred signal charge into a voltage are provided. When a CCD is used, the output amplifier 508 is often an FDA (Floating Diffusion Amplifier).

The above-described photodetector 502 will be described with reference to FIGS. 2A, 2B, and 2C.
The photodetector 502 prevents interference between each electrode, the photoelectric conversion unit 503 that converts incident light formed in the silicon substrate 301 into signal charges, and the photodetector 502 adjacent along the horizontal direction 522. And a detector separation 504. Such photo detectors 502 are arranged in a line in the vertical direction 521 to constitute a vertical CCD 509. Therefore, in the vertical CCD 509, as shown in FIG. 2C, for example, the first A transfer electrode 511A, the first virtual electrode 513, the first B transfer electrode 511B, the second A transfer electrode 512A, the second virtual electrode 514, and the second B transfer electrode 512B are cycled. These electrodes are repeatedly arranged. The first A transfer electrode 511A and the first B transfer electrode 511B may be collectively referred to as a first transfer electrode 511, and the second A transfer electrode 512A and the second B transfer electrode 512B may be collectively referred to as a second transfer electrode 512. . The extending direction of the first transfer electrode 511, the second transfer electrode 512, the first virtual electrode 513, and the second virtual electrode 514 corresponds to a direction perpendicular to the vertical direction 521, that is, the horizontal direction 522.
One photodetector 502 necessarily includes the first transfer electrode 511 and the second transfer electrode 512, and further includes one of the first virtual electrode 513 and the second virtual electrode 514.

The light detection principle of the light detector 502 will be described.
When light emitted from a subject to be imaged by the solid-state imaging device 300 enters the photodetector 502 in the detector array 501, the silicon substrate 301 has a number of electrons corresponding to the amount of incident light due to the internal photoelectric effect. Hole pairs (the signal charges described above) are generated. Here, a region in the silicon substrate 301 in which light is incident and electron-hole pairs are generated is referred to as a photoelectric conversion unit 503. For each photodetector 502, this signal charge (in many cases, electrons) is transferred through the vertical CCD 509 and the horizontal CCD 510 and converted into a voltage by the output amplifier 508 to obtain a captured image of the subject.

  Here, there are two types of photodetectors 502: a panchromatic detector that detects the entire light region, and a multiband detector that detects the light region by dividing the light region by arranging a color filter above. is there. In the present embodiment, both panchromatic detectors and multiband detectors are targeted. Further, the photodetector 502 can be classified into two types depending on the signal charge readout method. One is an area sensor in which a vertical CCD 509 and a photoelectric conversion unit 503 are arranged in parallel, and is a detector used when the readout method is frame transfer or interline transfer. The other one is a detector used when the vertical CCD 509 includes a photoelectric conversion unit 503, is a line sensor, and the readout method is TDI (Time Delay Integration). In the present embodiment, a TDI readout type line sensor is targeted.

The vertical CCD 509 in the solid-state imaging device 300 according to the present embodiment can be driven using two-phase clock pulses φ1 and φ2 that are 90 degrees out of phase with each other. In this case, the two-phase clock pattern is the pattern shown in FIG. The clock pulses φ1 and φ2 are supplied to the first transfer electrode 511 and the second transfer electrode 512, respectively, as shown in FIG.
With this driving method, signal charges generated in the respective photodetectors 502 constituting the vertical CCD 509 are sequentially transferred in the vertical direction 521 and output from the output amplifier 508 to the outside via the horizontal CCD 510.

  Next, a manufacturing method of the charge coupled device, that is, the vertical CCD 509 or the detector array 501 in this embodiment will be described with reference to FIG. FIG. 5 shows a cross-sectional structure along the vertical direction 521 of the solid-state imaging device 300.

  First, a silicon substrate 301 is prepared (FIG. 5A). Next, an impurity diffusion layer is formed on the surface of the silicon substrate 301 in a region where the vertical CCD 509 and the horizontal CCD 510 are formed on the silicon substrate 301 by using the impurity diffusion method or the ion implantation method, and the photoelectric conversion unit 503. And detector separation 504. Next, an isolation oxide film is formed at a specified position by LOCOS (Local Oxidation of Silicon) isolation method or trench isolation method (not shown). Next, a gate insulating film 304 is formed on the silicon substrate 301 (FIG. 5B).

Next, first transfer electrodes 511 are formed on the gate insulating film 304 with a gap in the vertical direction 521 (FIG. 5B). The first transfer electrode 511 extends along a direction perpendicular to the vertical direction 521, that is, along the horizontal direction 522. Next, a first insulating film 305 is formed so as to cover the first transfer electrode 511 ((c) in FIG. 5).
Next, second transfer electrodes 512 are formed on the first insulating film 305 so as to alternate with the first transfer electrodes 511 in the vertical direction 521 (FIG. 5C). The second transfer electrode 512 also extends along a direction perpendicular to the vertical direction 521, that is, along the horizontal direction 522. Next, a resist mask 530 is formed on the entire surface of the silicon substrate 301 so as to cover the second transfer electrode 512 and the like.
Furthermore, each region in the resist mask 530, the first transfer electrode 511, and the second transfer electrode 512 corresponding to the substantially central portion of the first transfer electrode 511 and the second transfer electrode 512 in the vertical direction 521 is etched. As a result, each of the above regions is removed, and an opening 531 is formed (FIG. 5D). Similar to the first transfer electrode 511 and the second transfer electrode 512, the opening 531 extends along a direction perpendicular to the vertical direction 521, that is, along the horizontal direction 522.

By the etching, the first transfer electrode 511 and the second transfer electrode 512 are divided at a substantially central portion in the vertical direction 521, and the first transfer electrode 511 becomes a pair of the first A transfer electrode 511A and the first B transfer electrode 511B. The second transfer electrode 512 is a pair of second A transfer electrode 512A and second B transfer electrode 512B.
As described above, in this embodiment, the first transfer electrode 511 and the second transfer electrode 512 are divided by etching along the extending direction to form a pair of electrodes, respectively. There is no insulating film in the cross section. In addition, since the first transfer electrode 511 and the second transfer electrode 512 of a single layer are etched instead of etching the overlapping portions of the transfer electrodes, the exposed surface after etching is made a uniform flat surface. Can do.

  Next, the first virtual electrode 513 and the second virtual electrode 514 are formed on the silicon substrate 301 by performing ion implantation through the opening 531 by self-alignment while leaving the resist mask 530 used in the etching of the opening 531 ( (D) of FIG. As a result, a first virtual electrode 513 is formed between the first A transfer electrode 511A and the first B transfer electrode 511B, and a second virtual electrode 514 is formed between the second A transfer electrode 512A and the second B transfer electrode 512B. The At this time, as described above, since there is no insulating film on the divided cross section of each electrode, ion implantation for forming the first virtual electrode 513 and the second virtual electrode 514 is not hindered. Therefore, the potential dip and the barrier in the first virtual electrode 513 and the second virtual electrode 514 can be reduced, and the charge transfer efficiency can be improved as compared with the conventional case. Further, there is no deviation in the formation positions of the first virtual electrode 513 and the second virtual electrode 514.

  Next, after removing the resist mask 530, a second insulating film 306 is formed so as to cover the second transfer electrode 512 ((e) of FIG. 5). Next, an opening is formed in the second insulating film 306 corresponding to the first A transfer electrode 511A, the first B transfer electrode 511B, the second A transfer electrode 512A, and the second B transfer electrode 512B to form a wiring layer (not shown). ). Finally, a protective film is formed (not shown). In this way, the charge coupled device portion of the solid-state imaging device 300 in the present embodiment is completed.

As already described, in the manufacture of the conventional charge coupled device, a virtual electrode is formed between the first transfer electrode and the second transfer electrode. Therefore, at the first transfer electrode end on the virtual electrode side, ion implantation into the virtual electrode is inhibited by the insulating film provided between the first transfer electrode and the second transfer electrode. Further, the formation position of the virtual electrode is shifted to one of the transfer electrodes due to the misalignment of the photoengraving. Further, since the transfer electrode portion overlapping the two layers is removed by etching, the surface after etching becomes non-uniform. As a result, potential dip and barrier occurred in the virtual electrode, and the charge transfer efficiency of the vertical CCD was low.
On the other hand, in the vertical CCD 509 of the solid-state imaging device 300 according to the present embodiment, as described above, the section of the first A transfer electrode 511A and the first B transfer electrode 511B, and the second A transfer electrode 512A and the second B A conventional insulating film does not exist in the cross section with the transfer electrode 512B. Further, the resist mask 530 used for etching the opening 531 is left, and ions are implanted into the opening 531 by self-alignment. Further, virtual electrodes 513 and 514 are formed at locations where the single-layer transfer electrodes 511 and 512 are removed by etching.
As a result, the ion implantation into the virtual electrodes 513 and 514 is not hindered by the insulating film in the divided section. In addition, there is no bias in the formation positions of the virtual electrodes 513 and 514. Further, the surfaces after the transfer electrodes 511 and 512 are removed by etching are uniform.
Therefore, since the potential dip and barrier in the virtual electrodes 513 and 514 can be reduced, the charge transfer efficiency of the vertical CCD 509 can be improved. That is, a charge coupled device having high charge transfer efficiency can be provided. Therefore, a solid-state imaging device having a high MTF (Modulation Transfer Function) can be provided.

  Further, since the performance of the solid-state imaging device can be improved as described above, the yield can be improved, and accordingly, the energy consumption can be reduced and the raw materials can be reduced.

Although the method for driving the charge coupled device in the present embodiment has already been described with reference to FIG. 4, it can also be driven as follows.
That is, the vertical CCD 509 in the solid-state imaging device 300 can be driven using four-phase clock pulses φ1, φ2, φ3, and φ4 that are different in phase by 90 degrees as shown in FIG. FIG. 7 shows a potential configuration diagram in this case. FIG. 7 shows the relative level of potential under each electrode with respect to the arrangement of the transfer electrodes 511 and 512 and the virtual electrodes 513 and 514.

In FIG. 7A, the voltages of the clock pulses φ1 and φ2 are at the low level, and the voltages of the clock pulses φ3 and φ4 are at the high level. In FIG. 7B, the voltages of the clock pulses φ2 and φ3 are at the low level, and the voltages of the clock pulses φ4 and φ1 are at the high level. In FIG. 7C, the voltages of the clock pulses φ3 and φ4 are at the low level, and the voltages of the clock pulses φ1 and φ2 are at the high level. In FIG. 7D, the voltages of the clock pulses φ2 and φ3 are at a high level, and the voltages of the clock pulses φ4 and φ1 are at a low level.
Signal charges generated by incident light are accumulated in the photoelectric conversion unit 503 below the electrode whose clock pulse voltage is at a high level. By repeating the operation in the order of (a) → (b) → (c) → (d) → (a) → (b) →..., Signal charges are transferred from left to right. The
Further, as shown in FIG. 8, the four-phase clock pulses φ1, φ2, φ3, and φ4 are supplied to the first A transfer electrode 511A, the first B transfer electrode 511B, the second A transfer electrode 512A, and the second B transfer electrode 512B. The

Embodiment 2. FIG.
The configuration (external appearance) of the solid-state imaging device 300-2 according to the second embodiment is the same as the configuration of the solid-state imaging device 300 according to the first embodiment shown in FIG. 1, and the photodetector 502 according to the second embodiment. The configuration and the light detection principle are the same as those in the first embodiment. Further, the driving method of the vertical CCD 509 of the solid-state imaging device 300-2 according to the second embodiment is the same as that in the first embodiment using the clock pulse shown in FIG. 3 or FIG.
On the other hand, the solid-state imaging device 300-2 according to the second embodiment is different from the first embodiment in the manufacturing method, as described below.

That is, in the first embodiment, as described above, ion implantation is performed through the opening 531 to form the virtual electrodes 513 and 514 on the silicon substrate 301. In the virtual electrodes 513 and 514, the number of times of ion implantation is set. And the ion concentration is the same.
On the other hand, in the second embodiment, the number of ion implantations and the ion concentration are made different in the virtual electrodes 513 and 514. In this respect, the second embodiment is different from the first embodiment. Therefore, in FIG. 9 for explaining the method of manufacturing the solid-state imaging device 300-2 according to the second embodiment, the steps from (a) to (d) are the steps from (a) to (d) in FIG. The description is omitted here. Hereinafter, the steps (e) and (f) of FIG. 9 will be described in detail.

In FIG. 9D, the first virtual electrode 513 and the second virtual electrode 514 are formed on the silicon substrate 301 by performing ion implantation through the opening 531 by self-alignment while leaving the resist mask 530. As a result, a first virtual electrode 513 is formed between the first A transfer electrode 511A and the first B transfer electrode 511B, and a second virtual electrode 514 is formed between the second A transfer electrode 512A and the second B transfer electrode 512B. The
Next, as shown in FIG. 9E, only one of the first virtual electrode 513 and the second virtual electrode 514 is ion-implanted with respect to the first virtual electrode 513 in the second embodiment. To do. In order to execute this, after a resist mask 532 is further formed on the resist mask 530, only the portion corresponding to the first virtual electrode 513 is removed and the opening 531 is formed. Then, ion implantation is performed again through the opening 531 corresponding to the first virtual electrode 513.

Next, after removing the resist masks 530 and 532, as shown in FIG. 9F, a second insulating film 306 is formed so as to cover the second A transfer electrode 512A, the second B transfer electrode 512B, and the like. . Next, an opening is formed in the second insulating film 306 corresponding to the first A transfer electrode 511A, the first B transfer electrode 511B, the second A transfer electrode 512A, and the second B transfer electrode 512B to form a wiring layer (not shown). ). Finally, a protective film is formed (not shown).
In this way, the solid-state imaging device 300-2 in the second embodiment is completed.

As described above, in the second embodiment, the first virtual electrode 513 and the second virtual electrode 514 in the vertical CCD 509 are different in the number and concentration of ion implantations, unlike the first embodiment. In the second embodiment, the first virtual electrode 513 is more ion-implanted than the second virtual electrode 514.
As described above, in the second embodiment, for example, even when there is a difference in potential between the first virtual electrode 513 and the second virtual electrode 514, adjustment is performed by ion implantation so as to reduce the difference. It is possible.

  The vertical CCD 509 of the solid-state imaging device 300-2 of the second embodiment described above adopts the same configuration as that of the solid-state imaging device 300 of the first embodiment except for the ion implantation operation. The same effect as that produced by the solid-state imaging device 300 can be obtained. That is, the ion implantation into the virtual electrodes 513 and 514 is not hindered, the bias of the formation positions of the virtual electrodes 513 and 514 is eliminated, and the surface where the transfer electrodes 511 and 512 are removed by etching becomes uniform. The solid-state imaging device 300-2 of the second embodiment can also reduce the potential dip and barrier in the virtual electrodes 513 and 514, and can improve the charge transfer efficiency of the vertical CCD 509.

  Furthermore, in the solid-state imaging device 300-2 according to the second embodiment, the potential difference between the first virtual electrode 513 and the second virtual electrode 514 can be reduced, so that the charge transfer efficiency of the vertical CCD 509 can be further improved. At the same time, the difference in light sensitivity between the photodetectors 502 adjacent along the vertical direction 521 can be reduced. That is, as compared with the charge coupled device in the first embodiment, the present second embodiment can provide a charge coupled device with higher charge transfer efficiency and less photosensitivity unevenness. As a result, it is possible to provide a solid-state imaging device that has a higher MTF and less photosensitivity unevenness than the solid-state imaging device of the first embodiment.

  Moreover, since the performance of such a solid-state imaging device can be improved, the yield can be improved, and accordingly, the energy consumption can be reduced and the amount of raw materials can be reduced.

300, 300-2 solid-state imaging device, 301 silicon substrate, 304 gate insulating film, 305 first insulating film, 306 second insulating film,
501 detector array, 502 photodetector, 504 detector separation,
508 output amplifier, 509 vertical CCD, 510 horizontal CCD,
511 1st transfer electrode, 511A 1A transfer electrode, 511B 1B transfer electrode,
512 Second transfer electrode, 512A Second A transfer electrode, 512B Second B transfer electrode,
513 first virtual electrode, 514 second virtual electrode, 521 vertical direction,
522 horizontal direction, 530 resist mask, 531 opening.

Claims (6)

A silicon substrate, a first transfer electrode formed on the gate insulating film on the silicon substrate at an interval, and a first transfer electrode formed between the first transfer electrodes via an insulating film formed on the first transfer electrode. A charge coupled device comprising two transfer electrodes and a first virtual electrode and a second virtual electrode formed in the silicon substrate,
In the vertical direction to transfer the signal charge generated in the charge-coupled device through the opening, the first transfer electrode has a pair of first 1A transfer electrodes and the 1B transfer electrodes, said second transfer electrodes, have a pair of first 2A transfer electrodes and the 2B transfer electrodes,
When viewed from the thickness direction of the charge-coupled device, both ends of the first virtual electrode are positioned corresponding to the first virtual electrode side ends of the first A transfer electrode and the first B transfer electrode, respectively.
When viewed from the thickness direction of the charge-coupled device, both ends of the second virtual electrode are respectively located corresponding to the second virtual electrode side ends of the second A transfer electrode and the second B transfer electrode,
In the vertical direction, each electrode is repeatedly arranged in the order of the first A transfer electrode, the first virtual electrode, the first B transfer electrode, the second A transfer electrode, the second virtual electrode, and the second B transfer electrode. Charge coupled device. A detector array in which a plurality of photodetectors having the charge coupled device according to claim 1 are arranged on a silicon substrate;
An output amplifier formed on a silicon substrate for amplifying the output of the photodetector;
A solid-state imaging device comprising: A method of manufacturing a charge coupled device according to claim 1,
Forming an impurity diffusion layer in a region for forming a vertical CCD and a horizontal CCD on the surface of the silicon substrate;
Forming a first transfer electrode at an interval on the gate insulating film on the surface of the silicon substrate;
Forming second transfer electrodes alternately with respect to the first transfer electrodes by interposing a first insulating film on the first transfer electrodes;
Using the resist mask formed on the second transfer electrode, the first transfer electrode and the second transfer electrode are etched to form an opening, and in the opening, the first transfer electrode is moved to the first A The transfer electrode and the first B transfer electrode are separated into the second transfer electrode and the second B transfer electrode, respectively.
A first virtual electrode is formed in the impurity diffusion layer between the pair of the first A transfer electrode and the first B transfer electrode by self-aligning and ion-implanting through the opening using the resist mask. Forming a second virtual electrode in the impurity diffusion layer between the second A transfer electrode and the second B transfer electrode;
A method for manufacturing a charge coupled device.   The method for manufacturing a charge coupled device according to claim 3, wherein ion implantation is further performed on one of the first virtual electrode and the second virtual electrode. The method for driving a charge coupled device according to claim 1, wherein a potential well is formed in the silicon substrate according to a voltage level applied to the electrode to accumulate and transfer the signal charge.
In the vertical direction in which the signal charge generated in the charge coupled device is transferred, the phase of the first A transfer electrode, the first B transfer electrode, the second A transfer electrode, and the second B transfer electrode in the order of the phases is 90. A method for driving a charge-coupled device, wherein two-phase clock pulses different in degree are sequentially supplied to apply a voltage to each electrode. The method for driving a charge coupled device according to claim 1, wherein a potential well is formed in the silicon substrate according to a voltage level applied to the electrode to accumulate and transfer the signal charge.
In the vertical direction in which the signal charge generated in the charge coupled device is transferred, the cycle of the first A transfer electrode, the first virtual electrode, the first B transfer electrode, the second A transfer electrode, the second virtual electrode, and the second B transfer electrode A method for driving a charge-coupled device, comprising: sequentially supplying four-phase clock pulses having phases different from each other by 90 degrees and applying a voltage to each electrode.

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