JPS5950962B2 - color filter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a color filter suitable for use in a solid-state color imaging device using, for example, a CCD (charge coupled device). It was designed to do so.

Prior to explaining the present invention, a solid-state imaging device using a CCD used in this example will be explained.

FIG. 1 shows an example of a CCD, which includes, for example, the main surface 1a of a P-type semiconductor substrate 1! :SiO. Insulating layer 2 such as
A plurality of electrode layers 3a, 3b, . V,
, V0 (V, > V0), the main plane 1
In the above example, carriers of Θ induced in accordance with the amount of light incident on the a side are accumulated in the electrode layers 3a and 3d. For example, in the case of a three-phase CCD 5, terminals 4a to 4C form a set, the corresponding terminals are commonly connected, and these three terminals 4a, 4b, and 4c are connected to one terminal in turn.
Clock pulses φA, φB, φC with a phase of 200
is supplied, and now the clock pulse φA is supplied only to the electrode 4a, a depletion layer 6 as shown by the dotted line in the figure is formed corresponding to the electrode layer 3a, and the induced carriers are accumulated here. . Then, as shown in FIG. 2, a clock pulse φBl is supplied to the electrode 4b (the applied voltage is V,
V2, V0 (V2>V1>V0)), the depletion layer 6 becomes the state shown in the figure, so carriers are transferred to the next electrode 4b.
By repeating this operation, the carriers are sequentially transferred. When such a CCD 5 is constructed as a solid-state imaging device, it is as shown in FIG. 3.

That is, the solid-state imaging device 10 includes an imaging section 11 as a light receiving section, a light-shielded accumulation section 12 for accumulating carriers obtained by the imaging section 11, and an output section 13 for outputting an imaging output signal 50'. configured. 14 indicates an output terminal.

A plurality of electrode layers 3 are formed on the main surface 1a of the semiconductor substrate 1 constituting the imaging section 11 and the storage section 12, as shown in FIG.
a, 3b..., 3a', 3b'..., but if n electrode layers are formed on the imaging section 11, the accumulation section The same number of n electrode layers are also deposited on 12.

In the direction orthogonal to these electrode layers 3a to 3n, 3a' to 3n', the CCD 5 is divided into a plurality of picture elements, and a channel stopper (
(shown with dotted lines) 7 are formed, and these are commonly connected. A positive voltage is applied to the commonly connected output terminal 8. Incidentally, in the region of the semiconductor substrate 1 where the channel stopper 7 is formed, a discharge region, ie, an overflow drain, for discharging excess carriers is formed.

This overflow drain is the fourth drain. As shown in the figure and FIG. 5, the stopper 7 is composed of an N'' region 16 formed within the P-type region 15a, and excess carrier generated when a large amount of light is received is emitted through this region 16. By the way, the solid-state imaging device 10 formed in this manner is driven by clock pulses φA to φC shown in FIG.

The outline of the driving operation will be explained next. Electrode layers 3a, 3d, 3
A first clock pulse φA having a predetermined repetition period shown in FIG. 6A is supplied to the first input terminal 4a derived from G. As shown in the figure, this first clock pulse φA transfers carriers induced in the semiconductor substrate 1 by light irradiation to the electrode layers 3a, 3d, 3g, . . .
The carrier accumulation parameters for accumulation in the depletion layer 6 corresponding to... It consists of a pulse φA, and a plurality of transfer pulses φA2 for sequentially transferring the accumulated carriers to the storage section 12, and the pulse width of the accumulation pulse φA, that is, the accumulation period (imaging period) Ta is as shown in FIG. The time from time T, corresponding to one field on the screen to T,. (1/60 second), while the entire period of the transfer pulse φA2 (period from time T. to T) is selected to be 1/100 of the period Ta.
~1/200 is selected, and the carrier is stored in the storage unit 12 at high speed transfer. Note that the transfer pulse φA
．． The pulse width W of (φ,...) is determined according to the number of picture elements. Electrode layers 3b, 3e, 3h...
The second clock pulse φB shown in FIG. 6B is supplied to the second input terminal 4b derived from .
The carrier accumulated in g... is transferred to this electrode layer 3b.
, 3e, 3h, . . . , there is no pulse corresponding to the accumulation pulse φA1 in the first clock pulse φA, but a transfer pulse φB similar to the first clock pulse φA. , has only .

A third clock pulse φc indicated by C in the figure is supplied to the third input terminal 4C. In this case as well, the transfer pulse φC. have only The first to third clock pulses φA to φC are 1 as shown in the figure.
The pulses are sequentially supplied to the terminals 4a to 4c with a phase difference of 20°, and at the current accumulation pulse φA, the electrode layers 3a, 3d, 3g, . . .
The carrier accumulated at ... is at time T.

The transfer pulse φB2 supplied in the electrode layer 3b,
The transfer pulse φC is transferred to the 3e, 3h, . and electrode layer 3C, 3
It is transferred to the f, 3i... side. Such an operation is performed during the transfer period Tb and is accumulated in the storage section 12, which is sequentially converted into an electric signal through the output section 13.
An imaging output signal SO having an output level corresponding to the amount of received light can be obtained from the output terminal 14. As mentioned above,
In the solid-state imaging device 10, when further obtaining a color video signal, a filter section dyed in a predetermined pattern is provided on the imaging section 11, which is a light receiving section, and a filter section dyed in a predetermined pattern is provided on the storage section 12 and the output section 13. In addition, it is necessary to provide a color filter with a light-shielding film.

However, when forming such a filter portion and a light-shielding film, the light-shielding film cannot have complete light-shielding properties using conventional dyeing methods, and when the light-shielding film and color filter are formed separately, Adhesion, etc., must be carried out, which has the drawback of significantly lowering the mounting accuracy of the color filter and complicating the manufacturing process. In view of these points, the present invention aims to provide a method for manufacturing a color filter in which a filter portion and a light-shielding film are integrally formed, and the light-shielding film has good light-shielding properties.

Hereinafter, an embodiment of the method for manufacturing a color filter according to the present invention will be described with reference to FIGS. 8, 9, and 10.

FIG. 8 shows the entire color filter, which is made of a transparent base material 20 such as gelatin or polyvinyl alcohol.
1 is dyed in a predetermined pattern to form a filter portion (indicated by coarse diagonal lines) 21, and silver is deposited on portions corresponding to the storage portion 12 and output portion 13 of the solid-state imaging device 10 to form a light-shielding film ( 22 (shown with thin diagonal lines).

To obtain such a color filter, the steps shown in FIGS. 9 and 10 are performed.

In FIG. 9A, the imaging section 11 of the solid-state imaging device 10. A photographic emulsion 30 containing silver salt is applied over the entire surface of the storage section 12 and the output section 13 .

Here, the photographic emulsion 30 used is one in which silver halide such as silver bromide is dispersed in a transparent base material such as gelatin or polyvinyl alcohol. In the solid-state imaging device 10 coated with this photographic emulsion 30, the portion corresponding to the imaging section 11 is shielded from light, and after exposure, this photographic emulsion 30 is developed, and as shown in FIG. Silver precipitates in the exposed area 32 and turns black (indicated by diagonal lines), and silver halide is removed from the light-shielded area 31.
Only the transparent base material remains.

Here, the silver is precipitated and the blackened portion has excellent light-shielding properties and forms a good light-shielding film 22. Furthermore, a dyeing filter is formed as shown in FIG. 10 in the light-shielded portion 31 in FIG. 9B where only the transparent base material 5 remains.

First, a photosensitive dye-resistant coating 40 is applied over the entire surface of the portion 31, and then the filter portion 21 is coated as shown in FIG. 10A.
The first color pattern (indicated by diagonal lines) 41 constituting the pattern is exposed to light while being shielded from light. After development, as shown in FIG. 10B, the dye-resistant coating on the light-shielded portion of the pattern 41 is removed, and the other portions (indicated by diagonal lines) 42 remain covered with the dye-resistant coating. In this state, dyeing with the first color is carried out, and the remaining dye-resistant coating is dyed. By peeling off the film 40, as shown in FIG. It is formed. Thereafter, by repeating the above-mentioned process, a second color filter (indicated by a thin diagonal line downward to the left) 4 is obtained, as shown in FIG. 1.10D.
4. Third color filter (indicated by rough diagonal line at the bottom right) 4
5 and 4th color filters (indicated by rough diagonal lines on the bottom left)
46 is formed to constitute the filter section 21.

As described above, according to the method of manufacturing a color filter according to the present invention, since the filter portion and the light-shielding film are integrally formed, there is no need to align the two filters, and the manufacturing process is simple and highly accurate.

Moreover, the light-shielding property of the light-shielding film is also good. Furthermore, in the above-described embodiment, the filter portion 21 is dyed repeatedly in a predetermined pattern.
As described above, the entire area is dyed with the first color, the predetermined pattern 41 is covered with a dye-resistant film, the others are bleached, and then the second pattern is dyed with the second color, and the second pattern is dyed with the dye-resistant film. It is also possible to cover the layer with a coating, decolorize the others, repeat this process, and then remove the dye-resistant coating at all stages when all the colors have been dyed.

Note that the method for manufacturing a filter according to the present invention is not limited to the above-described embodiments, and various other configurations may be adopted without departing from the spirit of the present invention.

[Brief explanation of the drawing]

Figures 1 and 2 are model diagrams for explaining the CCD;
The figure is a plan view showing an example of a solid-state imaging device, FIG. 4 is an enlarged plan view of a part thereof, and FIG. 5 is a sectional view taken along line I-1 in FIG. 4.
FIG. 6 is a waveform diagram of a black pulse used to drive a solid-state imaging device, FIG. 7 is a waveform diagram similar to FIG. 6 used to explain the operation of a CCD, and FIG. 8 is a waveform diagram of a color filter according to the present invention. FIG. 9 and FIG. 10 are diagrams illustrating an example of the manufacturing process of a color filter according to the present invention. 20 is a transparent base material, 21 is a dyed filter part, 2
2 is a light-shielding film on which silver is precipitated.

Claims (1)

[Claims] 1. A step of forming a transparent base material in which a photosensitive silver salt is dispersed over the entire surface of the imaging section, the storage section, and the output section of the solid-state imaging device, and the transparent base material corresponding to the storage section and the output section. A step of exposing a portion of the material to light and then developing it to deposit silver on the exposed portion to form a light-shielding film, and forming a dyed filter portion on a portion of the transparent base material corresponding to the imaging portion where the silver is not deposited. A method for manufacturing a filter for an imaging device, comprising the steps of: