JP2909789B2 - Linear color charge coupled device image sensor and charge transfer method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a charge coupled device image sensor (charge coupled device image sensor, hereinafter abbreviated as CCDIS) and a charge transfer method thereof, and more particularly to a linear color charge coupled device image sensor and a charge transfer method thereof. .

[0002]

2. Description of the Related Art As shown in FIG. 3, in a conventional CCDIS structure, three guiding pixels SA, SB, SC (usually red,
Ai, contains green three pixels), each of the induction pixels
Excites charges by light. Light at each guide pixel
Are excited by the transfer gates T1, T2,
After T3, each CCD transmission gate C ₁₁ , C ₁₂ , C
_21, C _22, C _31, and transmitted to C ₃₂ Ru output. However, the guide pixels of this type of CCDIS are relatively far apart from each other, and there is a time lag in the data transmission of each guide pixel during optical scanning, and one complete data corresponds to three guide pixels. Because it is the sum of data, in use, it partially occupies the hard memory and stores the data of each induction pixel,
After that, the corresponding data must be selected and recreated into one complete data, which not only wastes memory capacity, but also considerably increases the processing time of the software and the volume of the device used.

To solve the above problem, another type of C
Although CDIS is proposed, as shown in FIG. 4, the CCDIS includes three guide pixels SA1, SB1, and SC1.
Expected in, but is to array in close proximity to two induction pixel SA1, SB1, since another induction pixel SC1 separating still a both said induction pixel SA1, SB1 and one transmission gate C2 of You can't get enough effect. Furthermore, as shown in FIG. 5, although the other one or the other CCDIS the advent, CCDIS the seed is present a planar _{structure, S 11, S 12, S} 21, S 22 induction pixels in FIG. When each pixel is irradiated with light, the pixel is charged and after a certain period of integration, the charge is transferred from the transfer gates T ₁₁ and T ₁₂ to the vertical CCD.
Send to the transmission gates CV ₁ and CV ₂ , and further vertically
After transmission to the D transmission gate, the electric charge is output through the output port and output as an output signal. The distance between pixels in this type of structure is reduced to the size of one pixel, but the unit from that it contains in the induction pixel and transfer gate T ₁₁ vertical CCD transfer gates CV _1, the effective area of the induction leaving only half slightly, dielectric constant of the CCD is reduced greatly.

[0004]

SUMMARY OF THE INVENTION In view of the above-mentioned problems in the conventional charge-coupled device image sensor and its execution method, the present invention has a high light guide rate, saves software processing time, and improves the function of the system. It is another object of the present invention to provide a linear color charge-coupled device image sensor capable of reducing hardware installation costs and reducing the volume of a system to be used, and a charge transfer method thereof.

[0005]

In order to achieve the above object, the present invention relates to a first guide pixel SA0, which is located close to one side of the first guide pixel SA0 with an appropriate insulation interval.
Third induction pixel S to close to the other side of the second induction pixels SB0 are sequence; and a second induction pixels SB0 to be sequence
C0 and; second is disposed between the second induction pixel SB0 and third induction pixel SC0; the first induction pixel first provided in proximity to the other side of the SA0 of the transfer gate TA A second transfer gate TB; a third transfer gate TC provided close to the other side of the third guide pixel SC0; and a first transfer pixel provided outside the first transfer gate TA. First CCD that outputs charges excited by SA0
A transmission gate CH1; provided outside the third transfer gate TC, the second transfer gate TB and the third
A first vertical CCD transmission gate CVA for sequentially outputting charges excited by the second induction pixel SB0 and the third induction pixel SC0 supplied via the transfer gate TC; the first vertical CCD transmission The second lead pixel SA0 and the third lead provided outside the gate CVA and passed through the second transfer gate TB, the third transfer gate TC, the first vertical CCD transfer gate CVA. A second CCD transmission gate CH2 that is supplied with the electric charge excited by the pixel SB0, passes the electric charge excited by the third induction pixel SB0, and selectively outputs the second induction pixel SA0; It is provided outside of the second CCD transfer gates CH2, is passed to the third transfer gate TC, the first vertical CCD transfer gates CVA, the second CCD transfer gates CH2 Excitation of at serial third induction pixel SC0
A second vertical CCD transmission gate CVB for selectively passing the charged electric charges ; and the second vertical CCD transmission gate CVB.
, The third transfer gate TC, the first vertical CCD transmission gate CVA, the second CCD transmission gate CH2, and the second vertical CCD transmission gate CV.
Excited at the third guiding pixel SC0 passed through B
Structure from the third CCD transfer gates CH3 for outputting a charge
To achieve. Further, the carrier empty of the second guide pixel SB0 is used.
Become more preferably if Re be such a potential at the time of white is higher than the collector position of the third induction pixels SC0.

[0006]

[Action] is configured as described above, the present invention include, but are not sequence to the space between the respective CCD transfer gates CH1, CH2, CH3 longer three induction pixels SA0, SB0, SC0 of each induction three Pixels SA0, SB0, SC
0 tightly is an array with one another, and to ensure perfect induction area, of which is excited by induction pixel SA0 the first
The charged electric charge is transferred to the first transfer gate TA by the first transfer gate TA.
And transmit the CD transmission gate CH1, further outputs from the first output port O ₁ and transmitted horizontally in the order; also excited charge induction pixel SC0 the third, the third transfer <br From the gate TC, the signal is transmitted to the third CCD transmission gate CH3 via the first vertical CCD transmission gate CVA, the second CCD transmission gate CH2, and the second vertical CCD transmission gate CVB, and sequentially transmitted in the horizontal direction. Output from the third output port O ₃ : further excited by the second induction pixel SB0
Charges, after the third induction pixel SC0 is completely transmits the induced charge, a second transfer gate TB, the third induction pixel SC0, third transfer gates TC, the first vertical transfer gate CVA after being transmitted to the second CCD transfer gates CH2, further output from the second output port O ₂ and transmitted in the horizontal direction.

[0007] The capacitor of the second guide pixel SB0 is
As potential in the rear space is higher than the collector position of the third induction pixel SC0, and the second and third induction pixel S
B0 and SC0 are formed in the PNP type, and during the manufacturing process, the impurity concentration of the P-type layer on the upper surface of the second induction pixel SB0 is made higher than the impurity concentration of the P-type layer on the upper surface of the third induction pixel SC0. Is excited by the third guidance pixel SC0.
When the transfer of the charged electric charge is completed , the excitation is performed at the second induction pixel SB0 .
The generated charges can be transferred by the third induction pixel SC0.

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIG. 1, a charge coupled device image sensor according to the present invention comprises a first induction pixel SA0, a second induction pixel SB0, a third induction pixel SC0, and a first transfer gate T.
A, second transfer gate TB, third transfer gate TC, first CCD transfer gate CH1, second CCD transfer gate CH2, third CCD transfer gate CH3, first vertical C
CD transmission gate CVA, second vertical CCD transmission gate C
VB; wherein the first guidance pixel S
A0 is sequence in proximity to the second induction pixel SB0, second
Very thin at only the second transfer gate TB is provided, induction pixel SA0 said first first transfer gate adjacent to the other side during the induction pixel SB0 and third induction pixels SC0 of a first transfer gate TA and a first transfer gate close to the first transfer gate TA.
And it provided the CCD transfer gates CH1 respectively, CCD transfer gates CH1 of the first is equipped with a first output port O _1. On the other hand, induction pixel SC0 said third proximate the other side a third transfer gates TC, and third rolling
A first vertical CCD transmission gate C close to the transmission gate TC
VA, and a second CCD transmission gate CH2 in close proximity to the first vertical CCD transmission gate CVA, and in turn, the second CCD transmission gate CH2.
The second vertical CCD transmission gate CVB is connected to the CCD transmission gate CH2, and the third vertical CCD transmission gate CVB is
CCD transmission gate CH3 is provided in close proximity to the second
Providing an output port O ₂ of the CCD transfer gates CH2, an output port O ₃ of the CCD transfer gates CH3 of the third, respectively.

As can be seen from the above structure, each of C
The CD transmission gates CH1, CH2, CH3 are no longer in the space between each of the three guide pixels SA0, SB0, SC0.
Without being sequence, three induction pixel SA0, SB0, SC
0 is tightly array together, and has secured a perfect induction area, of which the charge induced pixels SA0 the first is insensitive, the charge through the first transfer gate TA first CCD transfer gate transmitted to CH1, further outputs from the first output port O ₁ and transmitted horizontally in the order; while charges induced pixels SC0 the third is sensitive, the third transfer gate <br/> over preparative 1st vertical CCD transmission gate CVA from TC, 2nd
The CCD transfer gates CH2, is transmitted to the third CCD transfer gates CH3 via the second vertical CCD transfer gates CVB, sequentially outputted from the third output port O ₃ and transmitted in the horizontal direction: The second Is excited by the lead pixel SB0 of
After waiting for transmission of the electric charge excited in the third induction pixel SC0 , the transferred electric charges are transferred to the second transfer gate TB, the third induction pixel SC0, the third transfer gate TC, The signal is transmitted to the second CCD transmission gate CH2 via the first vertical transmission gate CVA, and further transmitted horizontally to the second output port O2.
Output from ₂ .

Thus, what is most important for implementing the structure of the present invention is how to cause the third induced pixel SC0 to transfer the induced charge of the second induced pixel SB0. Te, the output processing of the other charge is software which is disposed just use the system, does not belong to the feature of the present invention omit description, charge converter is then characteristic of the present invention
The sending method will be described.

FIG. 2 is a cross-sectional view of each guide pixel in the present invention. As shown in FIG. 2A, the structure of each of the three guide pixels SA0, SB0, and SC0 is a PNP type. PA, P in the surface P type of each sensitive pixel
B, PC and PA ′, PB ′, PC ′ in the bottom layer P type are both at the ground potential, and N _A ,
N _B and N _C are joined in a floating state to store the induced charge,
When the electric charge is transmitted, the N-type layer becomes a hole and takes a positive potential.

A feature of the present invention is that the P-type layer PB on the upper surface of the second guide pixel SB0 located at the center is relatively high in P-type layer PB.
Embeds a type impurity concentration (secondary embedded), and a 3 P-type impurity concentration of the P-type layer PC induction pixel SC0 top the lower (primary embedding) of to, induction pixel of said 2 SB0
Electrostatic potential during a carrier blank is induced pixels SC0 the third
Position set higher relative to, and receives the induction pixel SB0 the second irradiation of the third induction pixels SC0 both light induced charge by the irradiated light (in (b) in FIG. shown as) is excited, when accumulated, the third transfer gate T
C is opened first, and the induced charge of the third induced pixel SC0 is vertically transmitted as in the above-described operation mode (as shown in (C) in the figure), and is also shown in (d) in the figure. As described above, in the process of transmitting the charge of the third induction pixel SC0,
When the transfer of the charge of the third inductive pixel SC0 is completed, the second transfer gate TB and the third transfer gate TC are simultaneously opened. Then, as shown in (e) in the figure, the electric charge of the second induction pixel SB0 is first transmitted to the third induction pixel SC0 having a lower potential , and further,
The transmission can be performed by following the same steps as in the above transmission method.

[0014]

Configured as described above according to the present invention, the present invention, respectively without sequence in the space between the respective CCD transfer gates CH1, CH2, CH3 three induction pixel SA0, SB0, SC0, induction of three Pixels SA0, SB0, SC
0 tightly distribution Resshi each other, and since has secured perfect induction area, spacing distance near each induction pixel, when the light scanning, there is no time lag in the induced charge transfer of each induction pixel, thus The software processing time can be reduced to improve the function of the system, and it is not necessary to add hardware, so that the hardware installation cost can be reduced, the volume of the system to be used can be reduced, and The first and third CCD transmission gates, the first and second transfer gates, the first and second vertical CCD transmission gates, and the like output the electric charge induced by the induction pixel of the first embodiment. In addition, the circuit configuration can be simplified, the space between the guide pixels can be reduced, and the guide pixels can be arranged at high density.

[Brief description of the drawings]

FIG. 1 is a structural view of the present invention.

FIG. 2 is a cross-sectional display diagram of an induced charge transmission mode in the present invention.

FIG. 3 is a structural view of a conventional CCDIS.

FIG. 4 is a structural view of another conventional CCDIS.

FIG. 5 is a structural view of a conventional planar CCDIS.

[Explanation of symbols]

SA0 First induction pixel SB0 Second induction pixel SC0 Third induction pixel TA First transfer gate TB Second transfer gate TC Third transfer gate CH1 First CCD transmission gate CH2 Second CCD transmission gate CH3 third CCD transfer gates CVA first vertical CCD transfer gates CVB second vertical CCD transfer gates O ₁ first output port O ₂ second output port O ₃ third output port

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-191467 (JP, A) JP-A-64-61163 (JP, A) JP-A-63-191467 (JP, A) JP-A-1- 241264 (JP, A) (58) Field surveyed (Int. Cl. ⁶ , DB name) H04N 9/07 H04N 5/335 H01L 21/339

Claims (4)

(57) [Claims] 1. A first induction pixel and (SA0); said first second induction pixels array in close proximity while maintaining a suitable insulating distance on one side of the induction pixels (SA0) (SB0)
When; provided in close proximity to the other side of said first induction pixel (SA0); third induction pixels array in proximity to the other side of the second induction pixels (SB0) and (SC0) A first transfer gate (TA); the second guide pixel (SB0) and the third guide pixel (S
Second transfer gate disposed between the C0) (TB)
A third transfer gate (TC) provided adjacent to the other side of the third guide pixel (SC0); and a first transfer gate provided outside the first transfer gate (TA). first CCD transfer gate for outputting the excited charge pixel (SA0) and (CH1); provided on the outside of the third transfer gate (TC), the second transfer gate (TB) and the second 3 through the transfer gate (TC).
0) and a first vertical CCD transmission gate (CVA) for sequentially outputting the charges excited by the third induction pixel (SC0)
When; provided outside of the first vertical CCD transfer gates (CVA), the second transfer gate (TB), the third rolling
Transfer gate (TC), the second guiding pixel (SA0) passed through the first vertical CCD transmission gate (CVA)
And the electric charge excited by the third induction pixel (SB0) is supplied, and the electric charge is excited by the third induction pixel (SB0) .
A second CCD transmission gate (CH2) for passing charges and selectively outputting the second induction pixel (SA0); and a third CCD transmission gate (CH2) provided outside the second CCD transmission gate (CH2). Transfer gate (TC) of the first vertical C
CD transmission gate (CVA), the third guiding pixel (SC) passed through the second CCD transmission gate (CH2)
0) a second vertical CCD transmission gate (CVB) for selectively passing the electric charge excited in 0); and a third vertical transfer gate (TC) provided outside the second vertical CCD transmission gate (CVB). ), The first vertical CCD transmission gate (CVA), the second CCD transmission gate (CH2), and the third guiding pixel (SC0) passed through the second vertical CCD transmission gate (CVB).
And a third CCD transmission gate (CH3) for outputting the charge excited in step (a). 2. The carry of said second guide pixel (SB0).
(A) The potential at the time of blank is calculated from the potential of the third induction pixel (SC0).
2. The linear color charge of claim 1, wherein the charge is high.
Coupling element image sensor. 3. The second and third guide pixels (SB0, SB0,
SC0) is formed into a PNP type, and in a manufacturing process,
The buried density of the P-type layer on the upper surface of the second induction pixel (SB0)
Of the P-type layer on the upper surface of the third induction pixel (SC0).
3. The line according to claim 1, wherein the density is higher than the embedding density.
Type color charge-coupled device image sensor. 4. The linear color charge coupling of claim 1, wherein :
In the element image sensor, the light emitted to the first guide pixel (SA0) is
The electric charge excited in the first induction pixel (SA0) is
From the first transfer gate (TA) to the first CCD transmission gate.
Port (CH1), and further in the horizontal direction in the first direction.
The signal is transmitted to the output port (O ₁ ) and output; the charge excited by the third induction pixel (SC0) is transferred to the upper port.
From the third transfer gate (TC) to the first vertical CCD
Transmission gate (CVA), said second CCD transmission gate
(CH2), the second vertical CCD transmission gate (CV)
B) and transmitted to the third CCD transmission gate (CH3).
To the third output port (O ₃ ) in the horizontal direction.
Transmitted and output; charge excited in the second induction pixel (SB0) is
The third induced pixel (SC0) transmits the induced charge
After that, the second transfer gate (TB)
A third induction pixel (SC0), the third transfer gate (T
C) through the first vertical CCD transmission gate (CVA)
To the second CCD transmission gate (CH2)
Are sequentially transmitted to the _second output port (O ₂ ) in the horizontal direction.
Outputs Te; linear color charge-coupled device image sensor comprising as
Charge transfer method.