JPS646616Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a color image sensor configured by integrating an image sensor body and a color separation filter.

For example, when making a one-chip color solid-state image pickup device using a charge transfer device such as a CCD (charge coupled device) or a BBD (bucket brigade device), a color separation filter is required. Conventionally, a color separation filter was made separately from the image sensor and was attached to the light-receiving surface of the image sensor using an adhesive. That is, an organic material dyeing base made of gelatin, polyvinyl alcohol (PVA), etc., for example, is formed on a predetermined glass substrate, and a dye-resistant mask such as photoresist is formed on this dyeing base to selectively dye the dye. By repeating the process, the dyed base was dyed differently to create a color separation filter, and this color separation filter was attached to the light-receiving surface of the image sensor. However, the color image pickup device having such a configuration has many problems as described below.

A glass substrate is required in the production of a color separation filter, and it takes time and effort to cut this substrate.

A special jig is required to bond the completed color separation filter to the device, that is, the image sensor body.

The adhesive layer for bonding has a thickness, and when this thickness increases, an erroneous signal (due to light) is generated due to leakage of adjacent light, resulting in poor S/N ratio. In order to avoid this, it is necessary to make the thickness of the adhesive layer as thin as possible, for example, 10 μm or less, which requires advanced technology.

When laminating color separation filters, misalignment easily occurs, making it difficult to achieve lamination accuracy.

It is difficult to provide a light-shielding area in a color separation filter that can completely block light with a single layer.

The present invention solves the above-mentioned problems and provides a color image sensor configured so that the manufacturing process is not complicated.

Hereinafter, an example of the color image sensor according to the present invention will be described in detail with reference to the drawings, along with its manufacturing method.

In the present invention, first, as shown in FIG. A, a solid-state imaging device 1 having a CCD configuration, for example, is provided. The figure particularly shows the light-receiving surface of the solid-state image sensor, and as usual, a plurality of light-receiving parts 2 [2
G, 2R, 2B] and a transfer section 4 having a transfer electrode 3 adjacent to the light receiving section 2 and transferring charges in one direction by two-phase or three-phase driving.

Next, on the light-receiving surface of the element 1 on which the color separation filter is to be formed, the light-receiving portion 2G on which the first color dyeing layer is to be formed and the portion to be light-shielded, that is, the other light-receiving portions 2R and 2B in the illustrated example, are formed. Then, an organic material dyeing base, for example, a gelatin base 5, is selectively formed on the transfer section 4. This gelatin base 5 is prepared by applying a mixed solution of gelatin and ammonium dichromate in a ratio of 9:1 to the entire surface of the light-receiving surface of the element, curing only the above-mentioned desired area by exposure to ultraviolet rays, and then It can be formed by removing the unhardened portion. Then, add this gelatin base 5 to 1
For example, the green dye layer 6 is immersed in a green dye solution.
form G (Figure B).

Next, a transparent isolation layer 7 made of, for example, KPR or TPR (both trade names) is deposited on the entire surface of the light-receiving surface including the green dyed layer 6G (Figure C). This isolation layer 7 is for preventing color mixing when forming the second and third color dyed layers to be formed later.

Next, the light receiving portion 2R on which the second color dye layer is to be formed is
A gelatin base 5 is selectively formed only on the area to be shielded from light by the same method as above, and this gelatin base 5 is immersed in a dye solution of a second color, for example, red, to form a red dye layer 6R (Fig. D).

Next, the same process is repeated, that is, after depositing a transparent isolation layer 7 on the entire surface (Fig. E), successively 3
A gelatin base 5 is selectively formed only on the light-receiving part 2B where a colored dyed layer is to be formed and a region to be light-shielded, and this gelatin base 5 is immersed in a third color, for example, a blue dyeing liquid, to form a blue dyed layer. Form 6B.

By doing so, as shown in FIG. A desired color image pickup device is obtained in which a light-shielding layer 8 that absorbs visible light is formed by laminating green, red, and blue dyed layers 6G, 6R, and 6B in the target area, that is, in this case, on the transfer section 4.

According to such a color image sensor, the trouble of bonding the image sensor 1 and the color separation filter 6 can be saved, and at the same time, the thickness of adhesive that occurs in conventional bonding is eliminated, so optical precision is improved and adjacent light is Erroneous signals due to signal leakage are minimized and the S/N ratio is improved. Furthermore, since a glass substrate is not required and the step of cutting this substrate is also eliminated when producing a color separation filter, labor savings can be expected. In addition, it becomes easier to create the color separation filter 6, and at the same time, three dye layers 6G and 6 are used in the area where light should be blocked.
Since R and 6B are laminated and a black filter is essentially formed by the additive coloring method, sufficient light shielding is achieved.
The characteristics of the image sensor as a whole are improved.

Furthermore, since the light shielding layer 8 can be formed in the color separation filter 6 at the same time in the process of creating the color separation filter 6, manufacturing of the image pickup device can be facilitated.

Also, since an isolation layer 7 is formed between each dyeing layer 6G, 6R, and 6B, mixing (bleeding) during dyeing is prevented.
is definitely prevented.

[Brief explanation of the drawing]

FIGS. 1A to 1F are cross-sectional views showing an example of a color image sensor according to the present invention in the order of steps. 1 is an image sensor, 2G, 2R, 2B are light receiving parts, 3
is a transfer electrode, 4 is a transfer section, 5 is a layer to be dyed, 6G,
6R and 6B are dyed layers, and 7 is an isolation layer.

Claims (1)

[Scope of utility model registration request] A color separation filter made of an organic substance and having a plurality of dyed layers is provided in direct contact with the light-receiving surface of the image sensor, and the plurality of dyed layers are laminated on areas to be shielded from light except for each light-receiving portion of the light-receiving surface. A color image sensor formed with a light-shielding layer.