JPH01133001A - Production of color separation filter - Google Patents

Abstract

PURPOSE:To improve accuracy and to reduce cost by subjecting plural kinds of multi-layered interference films repeatedly to a stage for forming an arbitrary kind of multi-layered interference film, then removing the multi-layered interference films except the necessary parts which are made to remain. CONSTITUTION:The 1st kind of multi-layered interference film 2 is formed on a solid-state image pickup element 1 and a resist 3 is coated thereon; thereafter, the resist 3 is patterned to leave only the desired parts. Multi-layered interference films 2a are then etched with the resist 3 as a mask in such a manner that only the desired parts thereof remain. The resist 3 is removed to form a multi-layered interference film filter 2a, following which an intermediate protective layer 4 is formed. This stage is repeated with the 2nd and 3rd kinds of multi-layered interference films to form multi-layered interference film filters 2a-2c in the respective positions. The entire part is coated with a protective film 5 to complete the color sepn. filter. Accuracy is thereby improved and cost is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for easily mass-producing color separation filters with high accuracy.

[Prior art and its problems] Color separation filters used in color image sensors, etc. are those that form a transparent organic polymer layer on the element and dye each pixel, or those that are colored organic polymer layers. Those in which a molecular layer is patterned are known.

However, although the conventional organic filters described above are advantageous in terms of productivity, they are disadvantageous in color characteristics and reliability.

In other words, it has poor heat resistance, is subject to large discoloration due to ultraviolet rays, etc., and because its color characteristics are determined by the color inherent to the dye, it is difficult to obtain desired spectral characteristics, and furthermore, it is difficult to form it accurately and inexpensively. be.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a method for mass-producing color separation filters accurately and inexpensively using a multilayer interference film made of an inorganic material that has excellent heat resistance and a large degree of freedom in color design.

[Means for Solving the Problems] A method for manufacturing a color separation filter according to the present invention includes a color separation filter in which a plurality of multilayer interference film filters of a plurality of types are arranged;
In the method of manufacturing evening meal.

The method is characterized in that, after forming an arbitrary type of multilayer interference film, the process of removing the multilayer interference film leaving only the necessary portions is repeated for a plurality of types of multilayer interference films.

[Operation] Since a color separation filter can be manufactured by simply repeating the process of selectively removing the multilayer interference film, it is possible to mass-produce it with high precision and easily by using photolithography or the like.

Furthermore, by using a multilayer interference film filter instead of an organic filter, thermal properties and color design freedom can be improved. That is, a multilayer interference film filter has a structure in which thin films with different refractive indexes are laminated, and by selecting the refractive index and film thickness, the center wavelength and passband width of the passband can be arbitrarily set.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

However, in the following embodiments, a method will be described in which a multilayer interference film filter having three types of spectral characteristics is formed on a solid-state image sensor 1 in which a plurality of optical sensors are arranged.

FIGS. 1A to 1G are manufacturing process diagrams schematically showing a first embodiment of the method for manufacturing a color separation filter according to the present invention.

First, a first type of multilayer interference film 2 is formed on the solid-state image sensor 1 by vacuum evaporation or the like ((A) in the same figure), and a resist 3 is applied thereon ((B) in the same figure).

Subsequently, the resist 3 is patterned to leave only a desired portion (FIG. 2(C)), and dry or wet etching is performed using the resist 3 as a mask. As a result, only the necessary portions of the multilayer interference film 1 and 2a are left behind (see figure (D)), the resist 3 is removed to form the multilayer interference film filter 2a (see figure (E)), and then the intermediate A protective layer 4 is formed (FIG. 4(F)).

The above process? 52 and the third type of multilayer interference film, the multilayer interference film filter 2 is placed at each position.
a, 2b and 2C are formed. Then, the entire structure is covered with a protective film 5 (FIG. 3(G)).

FIGS. 2(A) to 2(E) are manufacturing process diagrams schematically showing a second embodiment of the present invention.

In this example, first, the resistor 3 is coated on the solid-state image sensor 1 (see (A) in the same figure), and then patterned ((B) in the same figure).
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Next, the first type of multilayer interference film 2 is formed by a vacuum evaporation method or the like (see Figure (C)). By removing the resist 3, the multilayer interference film 2 on the resist 3 is also removed, and the multilayer interference film 2 in the necessary portions is removed. Leave only the membrane filter 2a ((D) in the same figure)
.

By repeating the above steps for the second and third types of multilayer interference films, multilayer interference film filters 2a, 2b, and 2C are formed at the respective positions, and finally the whole is covered with a protective film 5 to complete the process. Figure (E)).

FIGS. 3(A) to 3(C) are graphs showing the spectral characteristics of the multilayer interference film filter, respectively.

In the above embodiment, a method was described in which a filter was formed on a semiconductor called the solid-state image sensor 1, but the method is of course not limited to this. It can also be attached to.

Furthermore, it is also possible to apply the present invention to liquid crystal displays, etc., instead of image pickup devices.

[Effects of the Invention] As explained in detail above, the method for manufacturing a color separation filter according to the present invention does not require photolithography because the color separation filter can be manufactured by simply repeating the process of selectively removing the multilayer interference film. By using such methods, it becomes possible to mass-produce with high precision and easily.

[Brief explanation of the drawing]

FIGS. 1(A) to (G) are manufacturing process diagrams schematically showing a first embodiment of the method for manufacturing a color separation filter according to the present invention. FIGS. A manufacturing process diagram schematically showing the second embodiment, and FIGS. 3(A) to 3(C) are graphs showing the spectral characteristics of the multilayer interference film filter, respectively. ■...ψSolid-state imaging device 2...Multilayer interference film 2a, 2b, 2cma *Multilayer interference film filter 3...Resist 4...Intermediate protective layer 5...φprotective layer Agent Patent attorney Tsuki Yamashita Figure 1 (C) (E) Figure 2 (D) Figure 3 Ichibara table (illusion)

Claims (1)

[Claims] (1) In a method for manufacturing a color separation filter in which multiple types of multilayer interference film filters are arranged, after forming an arbitrary type of multilayer interference film, the multilayer interference film is removed leaving only the necessary portion. A method for manufacturing a color separation filter, characterized by repeating this process for multiple types of multilayer interference films.