JPS60118652A - Method for forming film - Google Patents

Abstract

PURPOSE:To obtain a film for filters having a uniform thickness, by spin coating a substrate having a surface consisting of a different material previously with an aqueous solution of a surfactant, and coating the resultant film with a regular solution of a photosensitive material. CONSTITUTION:An aqueous solution of a surfactant in about 0.2-2wt% concentration is uniformly applied to a glass substrate 1 having a light shielding layer 2 partially on the surface thereof by the spin coating method. The degree of hydrophilicity of the glass surface (a) of the glass substrate 1 and the light shielding layer surface (b) is equal. A coating solution of a water-soluble photosensitive material is then applied to the film by the spin coating method, and dried to form a film. Thus, the aimed film for filter layers having a uniform thickness without uneven spectroscopic characteristics is formed by the abovementioned method.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of forming a coating film on a water-soluble photosensitive material used for manufacturing color filters for solid-state imaging devices, for example.

Water-soluble photosensitive materials are used, for example, as red, green, and blue filter layers of color filters for solid-state imaging devices, but in this case, the thicknesses of these filter layers must be made as uniform as possible. This is because non-uniformity in the thickness of these filter layers causes, for example, variations in spectral characteristics.

Conventionally, spin coating is often used as a method for uniformly coating a thin film of water-soluble photosensitive material on a glass substrate for color filters for solid-state imaging devices. Since a light-shielding film consisting of a single layer, a chromium oxide layer/a metal chromium layer, a chromium oxide layer/a metal chromium layer/a chromium oxide layer, etc. The water-soluble photosensitive material applied to the glass substrate differs in its resistance to warping and warpage, resulting in uneven coating film thickness, thus forming a filter layer with a sufficiently uniform thickness over the entire surface of the glass substrate. It was quite difficult.

This invention has been made in view of the above circumstances, and provides a method for forming a uniform coating film of a water-soluble photosensitive material even on an object to be coated whose surface is made of such different materials. The purpose is to provide

That is, in a method of applying a coating liquid of a water-soluble photosensitive material to an object to be coated to form a coating film using a spin coating method, the present invention includes spin coating an aqueous solution of a surfactant prior to applying a heavy coating liquid. , and then spin-coating a heavy coating solution.

The surfactant used in the present invention is not particularly limited, and for example, an anionic surfactant having an SO6 group at the end can be used as appropriate. When this surfactant aqueous solution is used prior to spin coating of the coating heavy liquid, it is preferable to use the surfactant as a 02 to 2% by weight solution.

Next, a case in which the method of the present invention is applied to manufacturing a color filter for a solid-state image sensor will be described in comparison with a conventional example with reference to the drawings.

In Fig. 1, 1 is a glass substrate of a color filter for a solid-state image sensor (the material is quartz, low expansion glass, ordinary glass, etc.), and the upper surface is coated with a single layer of metallic chromium or chromium oxide and metallic chromium. A light shielding film 2 consisting of multiple layers is deposited. A color filter layer made of a water-soluble photosensitive material is formed on the upper surface of the glass substrate 1 as described below.
First, when a coating heavy liquid of a water-soluble photosensitive material is formed by a spin coating method as shown in Figure 1, the surface of a light-shielding film made of metallic chromium or chromium oxide becomes more hydrophilic than the glass surface of the substrate. Therefore, the coating layer 3 is relatively thick on the light shielding film 2 and relatively thin on the exposed surface of the glass substrate 1.

FIG. 2 shows the form of a coating film formed by the coating film forming method of the present invention. As in the case of FIG. 1, first, an aqueous surfactant solution is uniformly applied by spin coating to a glass substrate (1) having a partially light-shielding layer (2) on its surface.

By this operation, the coated surfaces of the glass substrate (1) have the same or similar degree of hydrophilicity on both the glass surface (a) and the light shielding layer surface (b).

After that, if a heavy coating solution is applied, a coating film (4) of approximately equal thickness is formed over the entire surface of the glass substrate (1), as shown in Figure 2, and the same film thickness is formed in the subsequent process. By dyeing the coating film, a colored filter layer that is homogeneous and has uniform spectral characteristics can be obtained.

In addition, if necessary, a surfactant may be added to the above coating heavy liquid.
, about 5 to 0.05% by weight may be added to further improve the wettability with the object to be coated.

Example A solution prepared by mixing 6 parts by weight of Finschgriu aqueous solution (solid content 40% by weight), 2 parts by weight of ammonium dichromate aqueous solution (25% by weight), and 12 parts by weight of water as the number of water-soluble photosensitive materials. I made it.

Next, a color filter substrate for a solid-state image sensor, in which a light-shielding film pattern of two layers of chromium oxide/metallic chromium with a thickness Q of 2.4'm was formed on a glass substrate, was set on the vacuum chuck stand of a spinner, and then an anion was removed. System surfactant〃
Konidanox ll (trade name, manufactured by Konishiroku Photo Industry C Co., Ltd.)
Prepare a surfactant aqueous solution consisting of 1 part by weight and 100 parts by weight of water, and apply this at 3000 rpm prior to applying the coating heavy liquid.
I made a spin code.

Then, apply the heavy coating liquid written on top of it at +000 rpm.
After spin-coding to a thickness of approximately 1.0 μMl, the coating was dried at a temperature of 80° C. for 20 minutes to form a coating film.

As a result, a coating film for a filter layer having a uniform thickness was formed over the entire surface, and a filter layer based on this coating also had uneven spectral characteristics.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing the state of a coating film obtained by a conventional method, and FIG. 2 is a sectional view showing the state of a coating film obtained by the present invention. (1)...Glass substrate (2)...Light shielding film (3)
・Coating film layer (4)...Coating film patent applicant Toppan Printing Co., Ltd.

Claims (2)

[Claims] (1) For a glass substrate that has a layer of a metal or metal compound on its surface that has a hydrophilicity different from that of glass in a ratio of y<B,
In a method of forming a coating film by applying a coating solution of a water-soluble photosensitive material using the spin coating method, an aqueous solution of a surfactant is spin-coated before applying the main coating solution, and then the main coating solution is spin-coated. A method for forming a coating film on a water-soluble photosensitive material. (2) The coating method according to claim 1, wherein the aqueous solution of the surfactant is a 0.2 to 2% by weight water bath solution.