JP2009302348A - Solid-state image pickup device and electronic information equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve efficient vertical and horizontal charge-transfer of signal charges by giving a transfer direction in each charge-transfer region under a plurality of electrodes arranged in a horizontal CCD on the side close to a vertical CCD. <P>SOLUTION: In a solid-state image pickup device 20 having two horizontal CCDs 4, 5, each transfer-direction oriented part 14 with a potential gradient D, to which a vertical transfer direction and a horizontal transfer direction are oriented, is formed in a plan-view trapezoidal region under each charge-transfer electrode 11A, 11B in a part under the two charge-transfer electrodes 11A, 11B provided on the horizontal CCD 4 close to a vertical CCD. Therefore, it is possible to efficiently execute charge-transfer of signal charges from the horizontal CCD 4, close to the vertical CCD, to the CCD 5 on side far from the vertical CCD without leaving behind charges unlike conventional one. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention uses a solid-state imaging device having a plurality of horizontal transfer units composed of a plurality of semiconductor elements that photoelectrically convert image light from a subject to image and uses the solid-state imaging device as an image input device in an imaging unit. For example, the present invention relates to an electronic information device such as a digital camera such as a digital video camera and a digital still camera, an image input camera, a scanner device, a facsimile device, and a camera-equipped mobile phone device.

  In recent years, conventional solid-state imaging devices have been improved in resolution and frame rate, and due to the accompanying high-speed driving of the horizontal CCD, there has been a problem such as deterioration in signal charge transfer in the horizontal direction and increase in power consumption. It has become.

  In order to solve this problem, it is considered that the drive frequency is lowered by providing a plurality of channels (a plurality of horizontal CCDs and their output units) in the horizontal CCD and its output unit. As described above, even if a plurality of horizontal CCDs are provided, the transfer efficiency when transferring the signal charges from the plurality of vertical CCDs from the horizontal CCD in contact with the vertical CCD to another horizontal CCD is low. This is the main cause of the deterioration of the yield of a conventional solid-state imaging device having a horizontal CCD.

  As means for solving this problem, Patent Document 1 proposes to improve the charge transfer efficiency by preventing the transfer charge from remaining.

  FIG. 6 is a plan view of a horizontal CCD showing a configuration example of a main part of a conventional solid-state imaging device disclosed in Patent Document 1. FIG. 7 is a waveform diagram of drive pulses applied to each electrode of FIG. 6 during the horizontal blanking period. FIG. 8 is a schematic diagram showing a cross-sectional structure along the line A-A ′ in FIG. 6 and a potential distribution under each electrode and a state of charge transfer of signal charges in each period t1 to t5 in FIG.

  6 to 8, the storage electrodes of the horizontal CCD 104 out of the horizontal CCDs 104 and 105 for distributing and transferring the signal charges from the alternately arranged vertical CCDs 102 and 103 are divided at a substantially central portion of the channel. It is composed of two electrode elements, a first electrode element 111A and a second electrode element 111B. The first electrode element 111 </ b> A constitutes a storage electrode of the horizontal CCD 105, and the second electrode element 111 </ b> B is connected in common with the barrier electrode 112. Reference numeral 108 denotes a metal wiring.

  The operation of the conventional solid-state imaging device 100 will be described below with reference to FIGS.

In the conventional solid-state imaging device 100, first, the signal charges accumulated under the final vertical transfer electrodes 107 of the vertical CCDs 102 and 103 are driven pulses ΦH1 applied to the horizontal transfer electrodes in the period t1, as shown in FIG. , ΦH2A, ΦH2B are simultaneously set to V _H, and the drive pulse ΦV _LAST applied to the final vertical transfer electrode 107 is set to _VL , thereby lowering the first electrode element 111A and the second electrode element 111B corresponding to the horizontal CCD 104. At the same time, the charges are transferred to the horizontal CCD 104 as the first signal charges 115 in FIG.

Next, in the period t2, as shown in FIG. 7, the drive pulse ΦT applied to the distribution gate electrode 106 is set to V _H , the drive pulses ΦH1 and ΦH2B are simultaneously set to _VL , and the drive pulse ΦH2A is set to V _H and V by the V _M which is an intermediate value of _L, the signal charges horizontally CCD104 and charge transfer smoothly to form a potential gradient under the storage electrode of the horizontal CCD104 the charge transfer to the distribution channel 106 as shown in FIG. 8 Is done.

Thereafter, in the period t3, as shown in FIG. 7, the drive pulse ΦH2A is set to _VL , thereby completing the charge transfer to the signal charge distribution channel 106 as shown in FIG.

Further, in the period t4, as shown in FIG. 7, the drive pulse ΦH1 is set to V _H , and the drive pulse ΦT By setting V _L to V _L , the signal charge of the distribution channel 106 is transferred to the horizontal CCD 105 below the storage electrode 109 as shown in FIG.

  On the other hand, the signal charge transferred from the vertical CCD 102 remains in the horizontal CCD 104 as it is by the channel stopper 101 on the distribution channel 106 in the period t2 to t4. In this way, the signal charges from the vertical CCDs 102 and 103 are distributed to the horizontal CCDs 104 and 105, respectively, and the distributed charge transfer of the signal charges from the vertical CCDs 102 and 103 is completed.

  Thereafter, in the period t5, the distributed signal charges are transferred horizontally in the two horizontal CCDs 104 and 105 toward the output unit (charge detection unit).

As described above, in the conventional solid-state imaging device 100, the storage electrode of the horizontal CCD 104 is configured by the plurality of electrode elements 111 A and 111 B, and the signal charge from the vertical CCDs 102 and 103 is transferred toward the distribution channel 106. By applying different drive pulses ΦH2A and ΦH2B as shown in FIG. 7 to the electrode elements 111A and 111B, a potential gradient is formed under the storage electrode of the horizontal CCD 104, and the horizontal CCD 105 is transferred from the horizontal CCD 104 via the distribution channel 106. In addition, the signal charge can be efficiently transferred.
JP-A-6-319081

  However, in Patent Document 1, in the solid-state imaging device having a plurality of horizontal CCDs, when charge is transferred from the horizontal CCD 104 closer to the vertical CCD to the horizontal CCD 105 farther from the vertical CCD, the charge storage capacity of the horizontal CCD 104 However, the potential of the horizontal CCD 104 is flat in the charge transfer region under each electrode, and the charge transfer region under each electrode is flat in the charge transfer region. Since there is no potential gradient, the remaining charges are likely to occur like the signal charges 114 described above. For this reason, the remaining signal charges 114 are mixed with the next second signal charges 116 and become noise components. There is a risk of becoming.

  The present invention solves the above-mentioned conventional problems, and each of the charge transfer regions is arranged in the charge transfer region under the plurality of electrodes arranged in the horizontal CCD on the side close to the vertical CCD, so that both the vertical direction and the horizontal direction are provided. It is an object of the present invention to provide a solid-state imaging device capable of efficiently transferring signal charges and an electronic information device such as a mobile phone device with a camera using the solid-state imaging device as an image input device in an imaging unit.

In the solid-state imaging device of the present invention, each signal charge read from a plurality of light receiving units that photoelectrically convert incident light to generate a signal charge is transferred in a first direction using a plurality of first charge transfer paths. A plurality of first charge transfer means, and each signal charge transferred from the plurality of first charge transfer means in a second direction orthogonal to the first direction using a plurality of second charge transfer paths. In a solid-state imaging device having a plurality of second charge transfer means for transferring charges,
A plurality of charge transfer electrodes are arranged in the width direction on the second charge transfer means on the side close to the first charge transfer means, and in each charge transfer region under the plurality of charge transfer electrodes, the first direction and The transfer direction directing portions in the second direction are respectively formed, whereby the above object is achieved.

  Preferably, the transfer directing portion in the solid-state imaging device of the present invention is configured such that a potential gradient for charge transfer is formed in the first direction and the second direction.

  Further preferably, the transfer directing portion in the solid-state imaging device of the present invention is formed by ion-implanting P-type impurities into a predetermined shape region in the charge transfer region into which N-type impurities are ion-implanted.

  Further preferably, the transfer directing portion in the solid-state imaging device of the present invention is formed by ion-implanting N-type impurities into a predetermined shape region in the charge transfer region into which N-type impurities are ion-implanted.

  Further preferably, the transfer directing portion in the solid-state imaging device of the present invention is ion-implanted with a uniform impurity concentration over a planar view shape.

  Still preferably, in a solid-state imaging device according to the present invention, the shape of the transfer directing portion in plan view is closer to the first charge transfer means than the length in the second direction far from the first charge transfer means. It is the shape which lengthened the length of the 2nd direction.

  Still preferably, in a solid-state imaging device according to the present invention, the shape of the transfer directing portion in plan view is closer to the first charge transfer means than the length in the second direction far from the first charge transfer means. It is the shape which shortened the length of the 2nd direction.

  Still preferably, in a solid-state imaging device according to the present invention, the shape of the transfer orientation unit in plan view is smoother in the second direction as it goes in the first direction from the side closer to the first charge transfer means to the side farther from the side. It becomes narrower in stages.

  Still preferably, in a solid-state imaging device according to the present invention, the shape of the transfer orientation unit in plan view is smoother in the second direction as it goes in the first direction from the side closer to the first charge transfer means to the side farther from the side. It is getting wider gradually.

  Still preferably, in a solid-state imaging device according to the present invention, the shape of the transfer orientation unit in plan view is narrower in one side in the second direction than in the first direction from the side closer to the first charge transfer means to the side farther from the first charge transfer means. It has become.

  Still preferably, in a solid-state image pickup device according to the present invention, the shape of the transfer orientation unit in plan view is such that one side is wider in the second direction than the first direction going from the side closer to the first charge transfer means to the side farther from the side. It has become.

  Further preferably, signal charges from the plurality of first charge transfer means in the solid-state imaging device of the present invention are allocated to the plurality of second charge transfer means.

  Further preferably, in the solid-state imaging device of the present invention, the shape of the transfer directing portion in plan view includes a trapezoidal shape having an inclined side on one side, a right triangle shape, and a trapezoidal inclined side having an inclined side on one side. It is at least one of the outside of the trapezoidal shape or the inside of the trapezoid.

  Furthermore, it is preferable that the number of the plurality of charge transfer electrodes in the solid-state imaging device of the present invention is at least two.

  Further preferably, the N-type impurity in the solid-state imaging device of the present invention is As (arsenic) or P (phosphorus), and the P-type impurity is B (boron).

  The electronic information device of the present invention uses the solid-state imaging device of the present invention as an image input device in an imaging unit, and thereby achieves the above object.

  With the above configuration, the operation of the present invention will be described below.

  In the present invention, a plurality of electrodes are arranged on the second charge transfer means closer to the first charge transfer means, and the charge transfer region under each electrode has a first direction and a second direction perpendicular thereto. A transfer directing portion having a potential gradient is formed on the surface.

  As described above, in the solid-state imaging device having the plurality of second charge transfer units, the transfer directing units are respectively provided in the charge transfer regions below the plurality of electrodes arranged in the second charge transfer unit closer to the first charge transfer unit. Thus, the signal charge is efficiently transferred in the first direction (vertical direction) without leaving any charges as in the conventional case, from the second charge transfer means closer to the first charge transfer means to the second charge transfer means farther. Charge transfer is possible. At the same time, by assigning the transfer direction in the second direction (horizontal direction) orthogonal to the above, it is possible to efficiently transfer the signal charge without leaving any charge in the second direction. Become.

  As described above, according to the present invention, in the solid-state imaging device having a plurality of second charge transfer means, the charge transfer regions under the plurality of electrodes arranged in the second charge transfer means closer to the first charge transfer means. Since each transfer direction directing portion is provided, the signal charge is efficiently transferred from the second charge transfer means closer to the first charge transfer means to the second charge transfer means far from the first charge transfer means in the first direction (vertical direction). Charge transfer to At the same time, by performing the transfer direction in the second direction (horizontal direction) orthogonal to this, it is possible to efficiently transfer the signal charges without leaving any charges.

  Embodiments 1 and 2 of the solid-state imaging device of the present invention and implementation of an electronic information device such as a mobile phone device with a camera using the solid-state imaging device 1 or 2 as an image input device in an imaging unit will be described below. The third embodiment will be described in detail with reference to the drawings.

(Embodiment 1)
FIG. 1 is a plan view of a horizontal CCD showing a configuration example of a main part of a solid-state imaging device according to Embodiment 1 of the present invention. FIG. 2 is a waveform diagram of each drive pulse applied to each charge transfer electrode of FIG. 1 during the horizontal blanking period. FIG. 3 is a schematic diagram showing a cross-sectional structure along the line BB ′ in FIG. 1, and a potential distribution under each charge transfer electrode and a state of charge transfer of signal charges in each period t1 to t5 in FIG. .

  1 to 3, the solid-state imaging device 20 according to the first embodiment receives a plurality of signal charges read from a plurality of light receiving units (not shown) that photoelectrically convert incident light to generate signal charges. A plurality of vertical charge transfer means (vertical CCDs) as a plurality of first charge transfer means for transferring charges in the vertical direction (first direction) using the vertical charge transfer paths, and a plurality of vertical charge transfer means. A plurality (two in this case) of horizontal charge transfer means (horizontal charges) as a plurality of second charge transfer means for transferring the signal charges in the horizontal direction (second direction) using a plurality of horizontal charge transfer paths. CCD).

  In this solid-state imaging device 20, each signal charge is delivered from the vertical final gate 7 of the vertical CCD as a plurality of columns of vertical charge transfer means for transferring the signal charges in the vertical direction, and each signal charge is assigned to two rows. Horizontal CCDs 4 and 5 as horizontal charge transfer means, and a distribution channel 6 disposed between the two horizontal CCDs 4 and 5 for separating the horizontal CCDs 4 and 5. The signal charge of the horizontal CCD 4 (charge transfer path) on the side close to the vertical CCD is transferred via the channel 6 to the horizontal CCD 5 (charge transfer path) on the side far from the vertical CCDs in a plurality of columns.

  On the distribution channel 6, a first-layer distribution electrode 15 made of a polysilicon film is disposed via an insulating film.

  As shown in FIG. 3, a second layer electrode 11A made of a polysilicon film and a third layer electrode 11B made of a polysilicon film are disposed on the horizontal CCD 4 via an insulating film. . A fourth layer electrode 10 made of a polysilicon film is disposed on these electrodes 11A, 11B, electrode 15 and electrode 9 with an insulating film interposed therebetween, and a barrier region 13 is formed below the electrode 10. Has been.

  Each of the horizontal CCDs 4 below the electrodes 11A and 11B is formed with a transfer direction portion 14 for transferring charges in the vertical direction. Further, the transfer direction unit 14 also serves as a horizontal transfer direction.

  The transfer orientation unit 14 is formed in a trapezoidal shape or a triangular shape having a long side near the vertical CCD and a short side near the vertical CCD. Further, the shape of the transfer orientation unit 14 in plan view is narrower with one side smoothly inclined in the horizontal direction with respect to the vertical direction as the first direction from the side closer to the vertical CCD to the side farther from the vertical CCD. It is formed in a trapezoidal shape or a right triangle shape.

  This is because the potential gradient D is formed in the vertical direction in the horizontal CCD 4. This is also intended to form a potential gradient in the horizontal direction in the horizontal CCD 4. The trapezoidal shape is easier to process because it has fewer acute angle portions than the right triangle shape.

  The transfer direction unit 14 ion-implants B (boron) into a predetermined charge transfer region (horizontal CCD 4) below the charge transfer electrode 11A and the charge transfer electrode 11B to form a potential gradient D in the vertical direction and the horizontal direction. However, considering the charge transfer in the horizontal direction, the amount of boron ions implanted in the transfer direction portion 14 must be smaller than the amount of boron implanted in the barrier region 13. Ions are implanted with a uniform boron ion implantation concentration into a predetermined area of a trapezoidal shape or a right triangle shape as a result. However, as a result, the amount of boron ions implanted is wide on the side close to the vertical CCD. As the distance from the vertical CCD increases, the area decreases.

When a P-type impurity B (boron) (or BF ₂ ) is ion-implanted into a predetermined region of the charge transfer region (horizontal CCD 4) into which N-type impurity P (phosphorus) or As (arsenic) is ion-implanted, a potential potential is obtained. Since the ion implantation amount of the horizontal CCD 4 decreases in the implantation area as it goes in the direction of the horizontal CCD 5 (vertical direction), the potential potential increases in the direction of the horizontal CCD 5 (vertical direction). It begins to tilt deeply. As described above, in the transfer orientation unit 14, the potential gradient D for charge transfer is formed in the vertical direction and the horizontal direction.

  In the case where the transfer direction portion 14 having a potential gradient (potential gradient D) is formed in a predetermined charge transfer region below the charge transfer electrodes 11A and 11B, as described above, the N-type impurity P (phosphorus) Or, in contrast to the case where the P-type impurity B (boron) is ion-implanted into the charge transfer region (horizontal CCD 4) into which As (arsenic) is ion-implanted, the N-type impurity P (phosphorus) or As (arsenic) is ionized. It may be considered that N-type impurities P (phosphorus) or As (arsenic) are ion-implanted into the implanted charge transfer region (horizontal CCD 4). As described above, when the N-type impurity P (phosphorus) or As (arsenic) is ion-implanted, the potential potential becomes deep, and therefore the shape of the transfer directing portion 14 in the plan view is the side closer to the vertical CCD. It is formed in a predetermined trapezoidal or triangular predetermined shape region with a short and far side. From the viewpoint of preventing charge from being left behind, it is better to make the potential potential shallower by ion implantation of P-type impurity B (boron).

  The operation of the solid-state imaging device according to the first embodiment will be described with the above configuration.

In the solid-state imaging device 20 according to the first embodiment, first, the signal charge accumulated under the vertical final gate 7 of the vertical CCDs 2 and 3 is applied to the horizontal transfer electrode in the period t1 as shown in FIG. pulses ΦH1, ΦH2A, simultaneously _{V H} and Faieichi2B, the drive pulse? V _LAST applied to the vertical last gate 7 to _{V L} from _{V H,} by the _{V L} drive pulse .phi.T, charge transfer electrodes corresponding to the horizontal CCD4 At the same time under 11A and 11B, the charge is transferred like the first signal charge 16 in FIG. 3 and the signal charge is accumulated in the transfer area of the horizontal CCD 4.

Next, in the period t2, as shown in FIG. 2, the drive pulse ΦT applied to the distribution gate electrode 15 is changed to V _H , and the drive pulses ΦH1 and ΦH2B are simultaneously changed from V _H to _VL , and the drive pulse ΦH2A By the V _M which is an intermediate value of the V _H and V _L, and the signal charges which have a vertical CCD3 are charge transfer is the charge transfer from the vertical CCD4 the distribution channel 6.

  In this case, the vertical CCDs 4 below the charge transfer electrodes 11A and 11B are each provided with a transfer direction portion 14 in the vertical direction, and a potential gradient D is provided in the vertical direction as shown in FIG. Accordingly, the transfer directing section 14 forms a potential gradient D (inclined portion) under the charge transfer electrodes 11A and 11B of the horizontal CCD 4 so that the signal charge can be smoothly transferred from the horizontal CCD 4 to the distribution channel 6 side without remaining charge. Forward.

Thereafter, at time t3, as shown in FIG. 2, by the driving pulse ΦH2A V _M from the V _L, to ensure charge transfer to the distribution channel 6 signal charges as shown in FIG.

Further, in the period t4, as shown in FIG. 2, the drive pulse ΦH1 is set to V _H and the drive pulse ΦT is set to _VL , whereby the signal charge of the distribution channel 6 is stored in the storage electrode 9 as shown in FIG. Charges are transferred to the lower horizontal CCD 5.

  On the other hand, the signal charge transferred from the vertical CCD 2 remains in the horizontal CCD 4 as it is by the channel stopper 1 on the distribution channel 6 in the period t2 to t4. In this way, the signal charges from the vertical CCDs 2 and 3 are distributed to the horizontal CCDs 4 and 5, respectively, and the transfer charge transfer of the signal charges from the vertical CCDs 2 and 3 is completed.

  Further, in the period t5, the second horizontal CCD 4 and 5 are transferred in the horizontal direction toward the output unit (charge detection unit), respectively, and the second charge newly transferred from the vertical CCD 3 to the horizontal CCD 4 is transferred. The signal charge 17 is not mixed with the remaining charge of the previous first signal charge 16 and becomes a noise component.

  As described above, according to the first embodiment, in the solid-state imaging device 20 having the two horizontal CCDs 4 and 5, the electric charges are charged in the two charge transfer electrodes 11 </ b> A and 11 </ b> B provided in the horizontal CCD 4 close to the vertical CCD. Since the transfer direction directing portion 14 for performing the transfer direction in the vertical direction and the horizontal direction is provided in a predetermined area below the transfer electrodes 11A and 11B, the horizontal CCD 4 on the side closer to the vertical CCD is shifted to the horizontal CCD 5 on the far side as in the related art. Thus, the signal charge can be efficiently transferred without leaving any signal charge. For this reason, the solid-state image sensor 20 with a high frame rate and a good yield can be obtained.

  Note that. In the first embodiment, the solid-state imaging device 20 having two horizontal CCDs has been described. However, the present invention is not limited to this, and there may be three or four horizontal CCDs or more horizontal CCDs. Good.

  In this case, the transfer direction portions 14 are formed in regions under the charge transfer electrodes formed on the horizontal CCD other than the horizontal CCD farthest from the vertical CCD.

  In the first embodiment, the case where two charge transfer electrodes are arranged on the horizontal CCD close to the vertical CCD has been described. However, the present invention is not limited to this, and three charge transfer electrodes are arranged. Or four charge transfer electrodes may be arranged, or more charge transfer electrodes may be arranged.

Furthermore, in the first embodiment, the shape of the transfer directing unit 14 is described as being wide on the side close to the vertical CCD and narrow on the far side, and the change is smooth. However, the present invention is not limited to this. Instead, it may be a case of changing in a staircase pattern.
(Embodiment 2)
In the first embodiment, the case where the horizontal CCD 4 on the side close to the vertical CCD is divided into two in the vertical direction and divided charges are transferred by the two electrodes has been described. In the second embodiment, the horizontal CCD 4 on the side close to the vertical CCD is described. A case will be described in which the CCD 4 is divided into four in the vertical direction and charge is transferred by four electrodes.

  FIG. 4 is a plan view of a horizontal CCD showing a configuration example of a main part of a solid-state imaging device according to Embodiment 2 of the present invention.

In FIG. 4, the solid-state imaging device 20 </ b> A according to the second embodiment has each signal charge from a vertical final gate (not shown) of a vertical CCD as a plurality of columns of first charge transfer means for transferring signal charges in the vertical direction. Are arranged between the two horizontal CCDs 4 and 5 as the second charge transfer means of the two rows to which each signal charge is allocated and these two horizontal CCDs 4 and 5 are arranged. And a sorting channel 6 for separation, and the signal charges of the horizontal CCD 4 (charge transfer path) on the side close to the plurality of columns of vertical CCDs are transferred to the horizontal CCD 5 (charge transfer path) on the side far from the plurality of columns of vertical CCDs. In order to transfer charges, a plurality (four in this case) of transfer electrodes 31 to 34 are arranged in the width direction of the horizontal CCD 4 on the side closer to the horizontal CCD 4 on the side closer to the vertical CCDs in the plurality of columns. .
The horizontal CCD 4 includes a transfer electrode 21 formed of a first polysilicon layer, and a plurality (four in this case) of charge transfer electrodes 31 to 34 in which a second polysilicon layer and a third polysilicon layer are alternately arranged. Has been.

  The horizontal CCD 4 applies each signal charge transferred from a vertical final gate (not shown) of the vertical CCD to the charge transfer electrode 21 and a drive pulse ΦH2 to the charge transfer electrodes 31 to 34. There are a case where charges are transferred in the horizontal direction by application, and a case where charges are transferred to the horizontal CCD 5 by applying drive pulses ΦHa31 to ΦHa34 to the charge transfer electrodes 31 to 34, respectively. Transfer direction portions 14A are formed in predetermined charge transfer regions under the charge transfer electrodes 31 to 34, respectively.

  In the horizontal CCD 5, a transfer electrode 21 formed of a first polysilicon layer and a transfer electrode 22 formed of a second polysilicon layer are repeatedly arranged in the horizontal direction, and a drive pulse ΦH 1 is applied to the transfer electrode 21. In addition to the application, the drive pulse ΦH2 can be applied to the transfer electrode 22 to transfer charges in the horizontal direction.

  The distribution channel 6 separates between the horizontal CCD 4 and the horizontal CCD 5 and is composed of a third polysilicon layer. The distribution channel 6 and the transfer electrode 21 are formed by the first polysilicon layer at the intersection. A channel stop portion 23 is provided under the charge transfer electrode 21 to separate the horizontal CCD 4 and the horizontal CCD 5 from each other.

  The external shape in plan view of the transfer directing portion 14A is formed in a trapezoidal shape or a triangular shape having a long side near the vertical CCD and a short side far from the vertical CCD. Further, the shape of the transfer direction portion 14A in plan view is such that one side is inclined stepwise in a horizontal direction with respect to the vertical direction as the first direction from the side close to the vertical CCD to the side far from the vertical CCD. It is formed into a trapezoidal shape or a right triangle shape that is narrow.

  This is because the potential gradient D is formed in the vertical direction in the horizontal CCD 4. This is also intended to form a potential gradient D in the horizontal direction in the horizontal CCD 4. The trapezoidal shape is easier to process because it has fewer acute angle portions than the right triangle shape.

The plan view shape of the transfer directing portion 14A is trapezoidal or triangular. However, the shape is not limited to this, and the inclined side of the trapezoid may swell outside the trapezoid. The sides may swell inside the trapezoid. The case where the trapezoidal inclined side swells inside the trapezoidal shape is indicated by the transfer directing portion 14B in FIG. 4 in place of the trapezoidal inclined side instead of the stepped one. In the case of the transfer direction unit 14B, it is difficult for the remaining charge to occur on the side farther from the horizontal CCD 5 in the horizontal CCD 4.
(Embodiment 3)
FIG. 5 is a block diagram illustrating a schematic configuration example of an electronic information device using, as an imaging unit, a solid-state imaging device including any one of the solid-state imaging devices according to the first and second embodiments of the present invention as the third embodiment of the present invention. is there.

  In FIG. 5, an electronic information device 90 according to the third embodiment includes a solid-state imaging device 91 that obtains a color image signal by performing various signal processing on the imaging signal from the solid-state imaging device 20 or 20A according to the first and second embodiments. A memory unit 92 such as a recording medium capable of recording data after processing a color image signal from the solid-state imaging device 91 for recording, and a predetermined signal for displaying the color image signal from the solid-state imaging device 91 The display means 93 such as a liquid crystal display device that can be displayed on a display screen such as a liquid crystal display screen after processing, and the color image signal from the solid-state imaging device 91 can be subjected to communication processing after predetermined signal processing for communication. And a communication means 94 such as a transmission / reception device.

  The electronic information device 90 is not limited to this, and in addition to the solid-state imaging device 91, at least one of a memory unit 92, a display unit 93, a communication unit 94, and an image output device 95 such as a printer. You may have.

  As described above, the electronic information device 90 includes, for example, a digital camera such as a digital video camera and a digital still camera, an in-vehicle camera such as a surveillance camera, a door phone camera, and an in-vehicle rear surveillance camera, and a video phone camera. An electronic device having an image input device such as an image input camera, a scanner device, a facsimile device, a camera-equipped mobile phone device, and a portable terminal device (PDA) is conceivable.

  Therefore, according to the third embodiment, based on the color image signal from the solid-state imaging device 91, it is displayed on the display screen, or is printed out on the paper by the image output device 95. (Printing), communicating this as communication data in a wired or wireless manner, performing a predetermined data compression process in the memory unit 92 and storing it in a good manner, or performing various data processings satisfactorily Can do.

  Although not particularly described in the first and second embodiments, a plurality of charge transfer electrodes are arranged in the width direction on the horizontal charge transfer means (horizontal CCD 4) on the side close to the vertical charge transfer means. In each charge transfer region under the plurality of charge transfer electrodes, vertical and horizontal transfer directing portions are formed. As a result, transfer directions are set in predetermined charge transfer regions under a plurality of charge transfer electrodes arranged in the horizontal CCD 4 on the side close to the vertical CCD, and signal charges are efficiently transferred in both the vertical and horizontal directions. The object of the present invention that can be achieved can be achieved.

  As mentioned above, although this invention has been illustrated using preferable Embodiment 1-3 of this invention, this invention should not be limited and limited to this Embodiment 1-3. It is understood that the scope of the present invention should be construed only by the claims. It is understood that those skilled in the art can implement an equivalent range based on the description of the present invention and the common general technical knowledge from the description of specific preferred embodiments 1 to 3 of the present invention. Patents, patent applications, and documents cited herein should be incorporated by reference in their entirety, as if the contents themselves were specifically described herein. Understood.

  The present invention uses a solid-state imaging device having a plurality of horizontal transfer units composed of a plurality of semiconductor elements that photoelectrically convert image light from a subject to image and uses the solid-state imaging device as an image input device in an imaging unit. For example, in a field of electronic information equipment such as a digital camera such as a digital video camera and a digital still camera, an image input camera, a scanner device, a facsimile device, and a camera-equipped mobile phone device, a plurality of solid-state imaging devices having a plurality of horizontal CCDs In the solid-state imaging device having the horizontal charge transfer means, the transfer directing portions are provided in the charge transfer regions below the plurality of charge transfer electrodes arranged in the horizontal charge transfer means close to the vertical charge transfer means. The remaining signal charge from the horizontal charge transfer means on the side closer to the charge transfer means to the horizontal charge transfer means on the far side The signal charge can be efficiently transferred in the vertical direction, and at the same time, the signal charge can be efficiently transferred without leaving the signal charge by performing the transfer direction in the horizontal direction orthogonal thereto. .

It is a top view of the horizontal CCD which shows the principal part structural example of the solid-state image sensor which concerns on Embodiment 1 of this invention. FIG. 2 is a waveform diagram of each drive pulse applied to each charge transfer electrode of FIG. 1 during a horizontal blanking period. FIG. 3 is a schematic diagram illustrating a cross-sectional structure taken along line B-B ′ in FIG. 1 and a potential distribution under each charge transfer electrode and a state of signal charge charge transfer in each period t1 to t5 in FIG. 2. It is a top view of the horizontal CCD which shows the principal part structural example of the solid-state image sensor which concerns on Embodiment 2 of this invention. It is a block diagram which shows the example of schematic structure of the electronic information apparatus which used the solid-state imaging device containing either of the solid-state image sensor of Embodiment 1, 2 of this invention for Embodiment 3 of this invention for an imaging part. It is a top view of the horizontal CCD which shows the example of a principal part structure of the conventional solid-state image sensor currently disclosed by patent document 1. FIG. FIG. 7 is a waveform diagram of drive pulses applied to each electrode in FIG. 6 during a horizontal blanking period. FIG. 8 is a schematic diagram illustrating a cross-sectional structure along the line A-A ′ in FIG. 6 and a potential distribution under each electrode and a state of charge transfer of signal charges in each period t1 to t5 in FIG. 7.

Explanation of symbols

1 channel stop 2, 3 vertical CCD
4, 5 Horizontal CCD
6 Distribution channel 7 Vertical final gate 8 Metal wiring 9, 10, 11A, 11B, 12, 21, 22, 31-34 Electrode 14, 14A, 14B Transfer directing section 15 Distribution electrode 20, 20A Solid-state imaging device D Potential gradient 90 Electronic information equipment 91 Solid-state imaging device 92 Memory unit 93 Display means 94 Communication means 95 Image output device

Claims (16)

A plurality of first charge transfer means for transferring each signal charge read from a plurality of light receiving units that photoelectrically convert incident light to generate a signal charge in a first direction using a plurality of first charge transfer paths. And a plurality of second charges that respectively transfer the signal charges delivered from the plurality of first charge transfer means in a second direction orthogonal to the first direction using the plurality of second charge transfer paths. In a solid-state imaging device having charge transfer means,
A plurality of charge transfer electrodes are arranged in the width direction on the second charge transfer means on the side close to the first charge transfer means, and in each charge transfer region under the plurality of charge transfer electrodes, the first direction and A solid-state imaging device in which the transfer direction directing portion in the second direction is formed.   2. The solid-state imaging device according to claim 1, wherein the transfer orientation unit is configured to form a potential gradient for charge transfer in the first direction and the second direction.   3. The solid-state imaging device according to claim 1, wherein the transfer directing portion is formed by ion-implanting P-type impurities into a predetermined shape region in a charge transfer region into which N-type impurities are ion-implanted.   The solid-state imaging device according to claim 1, wherein the transfer directing portion is formed by ion-implanting N-type impurities into a predetermined shape region in a charge transfer region into which N-type impurities are ion-implanted.   5. The solid-state imaging device according to claim 3, wherein the transfer directing unit is ion-implanted with a uniform impurity concentration over a planar view shape. 6.   The shape in plan view of the transfer direction portion is a shape in which the length in the second direction on the side closer to the first charge transfer means is longer than the length in the second direction on the side far from the first charge transfer means. The solid-state imaging device according to claim 3.   The shape of the transfer direction directing portion in plan view is a shape in which the length in the second direction on the side closer to the first charge transfer means is shorter than the length in the second direction on the side far from the first charge transfer means. The solid-state imaging device according to claim 4.   The shape in plan view of the transfer directing portion becomes narrower in the second direction as it goes in the first direction from the side closer to the first charge transfer means to the side farther from the first charge transfer means. 6. The solid-state imaging device according to 6.   5. The shape of the transfer directing portion in plan view becomes wider or gradually in the second direction as it goes in the first direction from the side closer to the first charge transfer means to the side farther from the first charge transfer means. 8. A solid-state imaging device according to 7.   9. The shape of the transfer directing portion in plan view is such that one side is narrower in the second direction with respect to the first direction from the side closer to the first charge transfer means to the side farther from the first charge transfer means. The solid-state image sensor in any one.   The shape of the transfer direction directing portion in plan view is such that one side is wider in the second direction with respect to the first direction toward the side farther from the side closer to the first charge transfer means. The solid-state image sensor in any one.   The solid-state imaging device according to claim 1, wherein signal charges from the plurality of first charge transfer units are allocated to the plurality of second charge transfer units.   A plan view shape of the transfer directing portion includes a trapezoidal shape having an inclined side on one side, a right triangle shape, and a trapezoidal inclined side having an inclined side on one side bulges outside or inside the trapezoidal shape. The solid-state imaging device according to claim 1, wherein the solid-state imaging device is at least one of the swollen ones.   The solid-state imaging device according to claim 1, wherein the number of the plurality of charge transfer electrodes is at least two.   5. The solid-state imaging device according to claim 3, wherein the N-type impurity is As (arsenic) or P (phosphorus), and the P-type impurity is B (boron).   An electronic information device using the solid-state imaging device according to claim 1 as an image input device in an imaging unit.

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