JPH021976A - Color solid-state image sensor - Google Patents

Abstract

PURPOSE:To eliminate a color mixture due to an obliquely incident light to improve an image sensing device provided with this device in reproducibility of image colors so as to obtain an image of high quality by a method wherein two or more light shielding layers are provided above a channel stopper of a CCD and between filter layers. CONSTITUTION:For instance, an obliquely incident light (a), which has penetrated through a third filter layer 12 of blue dye permissible only to a blue light wavelength, hits inevitably shielding layers 6 provided between the upside of a channel stopper of a CCDE and a filter layer D and is absorbed or reflected by the light shielding layer 6, so that the above incident light a is prevented from being incident on an adjacent channel b section, where only a blue light is incident, to be photoelectrically converted.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to a color solid-state imaging device.

(Prior Art) FIGS. 2 and 3 are side cross-sectional views IJ of two main parts of a frame transfer CCD imaging device, which is a conventional color solid-state imaging device. In order to colorize this kind of conventional frame transfer type CCDI imager, as shown in No. 2171, a sensor chip 81-- which consists of a glass filter A1CCD or the like formed with a desired color filter array on a glass plate. A method of aligning and bonding,
As shown in No. 31'E4, there is an on-one method in which a filter layer is sequentially formed directly on the wafer L with devices such as CCO formed on the wafer, as in the normal IC manufacturing process, and In the case of this conventional frame transfer, since the pixels are in close contact with each other, the color arrangement is often a vertical stripe.

Regarding the drawings, in Fig. 2, l is a glass plate, 2 is an intermediate layer,
3 is filter protective clothing, 4 is adhesive layer, 5 is protection 11q
(oxidation 1112), 6 is the color, iB, G at 1-JT of the channel stopper 8 between the adjacent pixels ga and 8a.
, R is a light-shielding layer formed of chromium, silicide, etc. in order to return light; 8 is a channel stopper that prevents signal charges stored in each pixel from diffusing to the neighboring pixels; 9 is a polyester layer; Silicon gate electrode, 10 is an oxide film, 11 is a red dye (R), 12 is a blue dye (B), 13
is a green pigment (G), and in FIG. 3, 6 is a light-shielding layer of only one layer disposed close to the channel stopper 8 between the filter layer and above the channel stopper 8 of the semiconductor sea urchin 80. Layer 7 is a flat layer.

As mentioned above, the light-shielding layer 6 in the conventional example shown in FIG. B), dye (G) 1 is formed in the middle part of dye (R), and since there was no light-shielding layer above the channel stopper 8 and between the filter layer, for example, dye (B) The oblique incident light a incident on the part is the pigment (B
) Pigment (G) passes through 12 and is not blocked by light! It reaches the channel b section of No. 3 and performs photoelectric conversion corresponding to the dye (G). In addition, the light shielding layer 6 in the conventional example shown in FIG. Since there was only one layer close to the channel stopper 8, and there was no layer between the channel stopper 8 and the filter layer, for example, obliquely incident light a incident on the dye (B) 12 part
) 12, most of the light that is not blocked by the one-layer light-shielding layer 6 reaches channel b of the dye (G) 13, and the dye (G)
Performs photoelectric conversion compatible with

The above description relates to a frame transfer type CCD image pickup device, or similar filter systems are also used in interline transfer type CCD image pickup devices and X-Y address type solid-state image pickup devices as conventional examples.

[Invention or problem to be solved]

As mentioned above, the conventional frame transfer type CCD
In the solid-state imaging device, as shown by the dotted lines in FIGS. 2 and 3, obliquely incident light a passes through a blue pigment (B) 12, which is a filter that transmits only the wavelength of fruits and vegetables, for example, and then passes through the edge thread light. It will be incident on the channel b part where it should be incident only.
The color is a mixture of blue and green. For this reason, there was a problem in that the color reproducibility of the image system of an imaging apparatus using this device was deteriorated.

Incidentally, even in conventional interline transfer type or XY address type solid-state image sensing devices, problems similar to those described above occur as the pixel size becomes smaller.

This invention was made to solve the above-mentioned problems, and aims to eliminate color mixing due to obliquely incident light, improve color reproducibility of the video system of an imaging device using this device, and obtain high-quality images. With the goal.

[Means to solve the problem]

Therefore, in the present invention, in a solid-state imaging device equipped with a CCD etc. and provided with a desired color filter layer above the image area, two or more layers are provided between the above channel stopper of the CCD and the curved filter layer. By providing a light-shielding layer, the objective is to achieve the above objectives.

In addition, the above objective is also achieved by providing two or more light-shielding layers between the filter layer and on the light-insensitive area adjacent to the photoelectric conversion region of the pixel.

(Function) The color solid-state imaging device of the present invention is provided with two or more light-shielding layers between the side of the channel stopper of the CCD and the filter layer, or on the light-shielding layer adjacent to the photoelectric conversion region of the pixel of the solid-state imaging device. Since two or more light-shielding layers are provided between the filter layer and the filter layer, for example, obliquely incident light that has passed through the dye that transmits only If-based wavelengths is blocked and does not enter the channel of the adjacent edge thread.

〔Example〕

An embodiment of the present invention will be described below based on the drawings.

FIG. 1 is a side sectional view of the main parts of a color solid-state imaging device according to an embodiment of the present invention, and in the figure, the same or equivalent components as in the above-described embodiments are denoted by the same symbols.

Next, the structure of this 7iK example will be explained in the order of its lamination.

In FIG. 1, CCD E is a channel stopper region 8. which is a region that serves as a commonly used photoelectric conversion and transfer channel, and a region P9 in the case of signal charges or electrons. An accumulation region for accumulating signal charges, a horizontal readout register, an output amplifier, etc. (not shown except for the channel stopper) are fabricated by a known ion implantation method, and oxidized IIA 10 is placed on top of them.
, polysilicon, aluminum, etc. are laminated, and an oxide 11Q 5 is formed as a protective film on top of the gate electrode 9 . Above the channel stopper 8 of such a CCDH, two or more layers, in this case two layers of light shielding layer 6, or an oxide film 5 as a protective film is formed in the gap between them, and the - part is the most Oxidation 1 as upper protective film
1!25 is formed. Next, a flattening layer 7 made of transparent resin or the like is formed on top of this oxidized IIQ 5, and the CCD
A desired filter layer is provided above the image area F of E. The filter layer.

For example, the first filter 13 transmits only the green (G) wavelength. Transparent intermediate layer 2. For example, a second filter 11 that transmits only red (R) wavelengths, a transparent intermediate layer 2. Blue (B
), and the protective film 3 is laminated on top of the third filter layer 12, which transmits only the wavelengths of the filter layer 12.

Next, the operation of this embodiment will be explained using FIG.

In FIG. 1, the oblique incident light a that passes through the third filter layer 12, which is a blue pigment that only transmits the wave 1 of the front thread, always passes through the channel stopper 8 of the CCDE. - A channel 6 that hits either of the light-shielding layers 6 disposed between the filter layer and the light-shielding layer 6, is absorbed or reflected by the light-shielding layer 6, and only the obliquely incident light a or the light from the adjacent edge thread enters the channel 6.
The light enters the area and is not photoelectrically converted.

The above has described the frame transfer 51 ICCD solid-state imaging device, or in the case of an interline transfer or X-Y address type solid-state imaging device, the photoelectric conversion area of the pixel of the solid-state imaging device, for example, the non-photosensitive area adjacent to the photosensitive area. For example, by providing two or more light-shielding layers between the -F side of the transfer section, which usually has a channel striker, and the filter layer, it is possible to obtain the same structure and operation as the above-mentioned frame transfer type.

〔Effect of the invention〕

As described above-1-, according to the present invention, in a solid-state imaging device including a CCD and the like and provided with a desired filter layer above an image area, two layers are provided above the channel stopper of the CCD and between the filter layer. By providing the above light-shielding layer, or by providing two or more light-shielding layers between the upper part of the light-insensitive area adjacent to the photoelectric conversion region of the solid-state imaging device and the filter layer, color mixing due to obliquely incident light is eliminated, and this device can be This has the effect of increasing the color reproducibility of the video system of the imaging device used and producing high-quality images. .

[BRIEF DESCRIPTION OF THE DRAWINGS] FIG. 1 is a side cross-sectional view of the main parts of a color solid-state imaging device according to an embodiment of the present invention, and FIGS. 2 and 3 are side sectional views of main parts of a conventional color solid-state imaging device. FIG. A... Glass filter B... Sensor chip C... Semiconductor wafer D... Filter layer E... CCD F...・Image area 6... Light shielding layer 8... Channel stopper 11... Second filter (red) 12... Third filter (I"f) 13 ...
...First filter (green)

Claims (2)

[Claims] (1) In a solid-state imaging device equipped with a CCD or the like and provided with a desired filter layer above an image area, the CCD
2 between the channel stopper of the CD and the filter layer.
A color solid-state imaging device characterized by having more than one light-shielding layer. (2) The color solid-state imaging device according to claim 1, characterized in that two or more light-shielding layers are provided above the light-insensitive portion adjacent to the photoelectric conversion region of the pixel and between the filter layer.