JPS59122072A - Color charge transfer device - Google Patents

Abstract

PURPOSE:To obtain a color signal with high resolution and to prevent color mixture by providing two arrays of photosensitive part areas and three arrays of read register parts. CONSTITUTION:Transfer registers 43-45 are arranged in three parallel arrays; a photosensitive part 1a is disposed between the registers 43 and 44 and a photosensitive part 1b is disposed between the registers 44 and 45. The photosensitive part 1a is provided with a red filter 49, and green filter 51 repeatedly by turns for respective picture elements along the array direction, and the photosensitive part 1b is provided with the filter 51 and a blue filter 50 alternately. Thus, the filters are arranged repeatedly, so the resolution does not deteriorate as compared with a black-and-white; and the register parts consists of three areas 43, 44, and 45, so signals of red, green, and blue are transferred independently by the respective registers to prevent the occurrence of color mixture due to transmission loss.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a charge transfer device, and more particularly to a charge transfer device for -dimensional color.

[Technical background of the invention]

One-dimensional color charge transfer devices are often used in photosensitive parts of facsimile machines, copiers, optical character readers (OCR), and the like.

FIGS. 1(8) to 1(C) show an example of a Pu'er channel type one-dimensional color charge transfer device that has been commonly used in the past. In Figure 1, (b) is a cross-sectional view taken along line A-A in (a), and (C) is a cross-sectional view taken along line B-B in (a). In Figure 1, the charge transfer device is functionally Broadly divided into photosensitive parts that generate and accumulate signal charges in response to optical signals.
, charge transfer shift registers (also called read registers) 2 and 3 that read and transfer the signal charges, and electrodes that control the read and transfer of the accumulated signal charges. It consists of

The photosensitive part l has the following structure. First, an insulating film (5i0
2, etc.)/2 is provided on which conductor electrode (polysilicon, etc.)/3. Further, near the surface of the semiconductor substrate //, an impurity semiconductor region /3 containing a high concentration of impurity of the λ-th conductivity type opposite to the semiconductor substrate // is provided. Further, a part of the impurity semiconductor region/S, a conductor electrode/3. A silicon oxide film with good light transmittance is provided on /μ, control electrodes + and j, and shift registers 2 and 3 by CVD. A pair of optically opaque light sole films /q, 2.0 are provided on this silicon oxide film 1g to form a slot that allows light to pass only over the impurity semiconductor region /3. Furthermore, impurity semiconductor region/! ; on top and a light shielding film/
9. A color filter 30 is provided on the silicon glass surface retention film 2/ including the area where 20 is opened. 0 An overcoat layer 3II is provided on this color filter 30 to protect the filter. . As shown in FIG. 1(a), the color filter 30 includes a green (G) filter 3/, a red (R) filter 32, and a red (R) filter 32 for each pixel.
Blue (B) filters 33 are arranged, respectively.

R and B filters are arranged so as to alternately repeat b
Ru.

Next, the operation will be briefly explained. Conductor electrode/3. When a voltage is applied between the conductor electrode /3' and the semiconductor substrate // to form a depletion layer on the surface of the semiconductor substrate // under the conductor electrode /3', the conductor electrode /3. A channel stopper of the same conductivity type as the semiconductor substrate /I and a potential well having 21A as a potential barrier are formed below Il/-. Signal charges generated in response to light are accumulated in this potential well, and the accumulated signal charges are transferred to the control electrode, which operates as an optical sensor element. , shift register, 3 as an output signal.

[Problems with background technology]

As mentioned above, when creating a color charge transfer device, a method is used in which a device normally used for black and white is configured to extract color signals by combining filters for each of the three primary colors, red, green, and blue. is taken. However, this method has a problem in that since the three primary color filters are allocated to the photosensitive area, the resolution in the horizontal direction (in the pixel arrangement direction) is reduced to 50%. To solve this problem, the number of pixels in the horizontal direction could be tripled, but with the current level of technology, the chip size would have to be extremely large. Furthermore, since the transfer efficiency of the registers is not ioo%, there is a problem in that when transfer is performed using two registers, color mixing of red, green, and blue inevitably occurs.

[Purpose of the invention]

Therefore, the present invention provides
Another object of the present invention is to provide a color charge transfer device that does not cause color mixing due to transfer loss.

[Summary of the invention]

In order to achieve the above object, the color charge transfer device according to the present invention includes first, first, and third readout registers arranged in parallel, and provided between the seventh and second readout registers. a first photosensitive section arranged on each pixel such that a red filter and a green filter are arranged alternately for each pixel in the pixel arrangement direction; and between the second and third readout registers. and a first filter arranged on each pixel such that green filters and blue filters are arranged alternately for each pixel in the pixel arrangement direction.
A photosensitive section is provided, and red, green, and blue image signals are independently read out from the first, first, and third readout registers, respectively.

[Embodiments of the invention]

Embodiments of the color charge transfer device according to the present invention will be described below with reference to the drawings. An example of a Pu-erh channel type two-dimensional color charge transfer device according to the present invention is shown in FIG.
Shown in a) to (C). (b) is a sectional view at A- in (A),
(C) shows a BB' cross-sectional view of (a).

In the charge transfer device, as shown in FIG. 2(a), a first transfer register 3, a first transfer register bowl, and a third transfer register box are arranged in three rows, and the first and second transfer registers are arranged in three rows. Register Hiro 3. A first photosensitive portion la is placed between the frame, a first and third transfer register stop, and a second photosensitive portion /b is placed between the frame.

In the seventh photosensitive section 8, a red filter t9 and a green filter S are arranged on each pixel in the arrangement direction.
0 to 9 are arranged so that / are repeated alternately, red (R), green (G), R, C from pressure in Figure 2 (a)
, , R, G......

In the second photosensitive section /b, green filters S/ and blue filters 50 are similarly provided on each pixel so as to be repeated alternately for each pixel along the arrangement direction.
From the left in Figure 2 (,), green (G), blue (B),
They are arranged like G, B, G, B...

3! ;, 3/, J7.3g indicates a storage electrode for temporarily storing signal charges generated in the seventh and second photosensitive portions /a and /b. 3q, 4to, Hiro/, ≠Y indicate control electrodes that control the transfer of signal charges.

Next, the pixels (
The structure of the sensor element (sensor element) will be explained in detail. In addition, the parts in FIGS. 1(b) and 1(c) that overlap with those in FIG. 7 are given the same reference numerals and will be described below.

After forming a buried channel layer with a 33° angle on the semiconductor substrate 11, an insulating film (5i02, etc.)/2 is provided, and storage electrodes 3j, 36. ,?
7°3g is provided to protect it. Further, an impurity semiconductor region /3 having a high impurity concentration and having a conductivity type opposite to that of the substrate / is provided near the surface of the semiconductor substrate / / . After that, a silicon oxide film with good light transmittance formed by CVD is formed over the entire surface, and the original shield film (for example, aluminum, etc.) +,! i,? -7. A plaza will be set up. Then, a red filter IAq, a blue filter 50, and a green filter S/ are provided via a surface protection film such as phosphor glass.

These color filters 't9.30. ．． The general manufacturing method for 3/ is to apply photoengraving to form a stripe or mosaic pattern on a relatively smooth surface protective film 2/, and then dye or otherwise process the pattern to obtain predetermined spectral characteristics. 9.30 for each color filter with a coloring pattern of 0. ! An intermediate layer made of, for example, nitrocellulose is provided between the / as a protective layer. As a matrix for color filters, for example, gelatin to which dichromate is added is dyed with an acid dye or the like to obtain various color patterns. Thereafter, in order to protect the colored pattern, an overcoat layer 3t made of a polymer material such as nitrocellulose having good light transmittance is formed.

By the way, the color filters are the seventh and second photosensitive parts /a,
/b, the arrangement is repeated as shown in FIG. 2(a), but by doing so, especially the green signal is transmitted to the first and second photosensitive portions la.

/b, the resolution is not inferior to the case where everything is black and white. Also, the register section is set to the first. 2nd and 3rd three areas IA; 7. u.

Since it is constructed using a box, each of the red, green, and blue signals is transferred independently by each register, so it is possible to prevent color mixing due to transfer loss as in the conventional case.

In the above embodiment, primary colors of red, green, and blue were used as the three primary colors, but it goes without saying that complementary colors using yellow, cyan, and green can be applied.

〔Effect of the invention〕

According to the present invention, the photosensitive area is arranged in one row,
By having a structure with three rows of read register sections,
The goal is to obtain high-resolution color signals without particularly increasing the chip size in the longitudinal direction.In addition, each color signal is transferred independently from each register, so it is an excellent color signal that does not cause color mixing. Provides charge transfer devices.

[Brief explanation of drawings]

Figure 1 shows an example of the structure of a conventional color charge transfer device, in which (a) is a plan view, (b) is a sectional view taken along line A-A' in (a), and (C) is B in (, ). -B' sectional view, FIG. 1 shows an embodiment of the color charge transfer device of the present invention, (8)
is a plan view, (b) is an AA' sectional view of (,), and (C) is a BB' sectional view of (,). /a...7th photosensitive section, /l)...1st photosensitive section, Hiro 3
...First read register, 1I-1l...Second read register, ys...Third read register, ti
to-Hiroyu...control electrode, t9...red filter,
50...blue filter, 3/...green filter. Applicant's agent Kiyoshi Inomata Figure 1 (a) (b) 1 (C) Figure 2 (a) 1] b-

Claims (1)

[Claims] First, second, and third readout registers arranged in parallel, and a red filter and a green filter provided between the seventh and second readout registers in the pixel arrangement direction. and are arranged on each pixel alternately for each pixel.
With the photosensitive part. A first filter provided between the second and third readout registers and arranged on each pixel such that green filters and blue filters are alternately located for each pixel in the pixel arrangement direction.
1. A color charge transfer device, comprising: a photosensitive section, wherein red, green, and blue image signals are independently read out from each of the first, second, and third readout registers.