JPS62242360A - Color solid-image sensor - Google Patents

Abstract

PURPOSE:To greatly reduce coating irregularities attributable to steps by a method wherein a micro color filter element is removed from over an electrode pad section and at least the flattened layer of the micro color filter element is retained on a dicing section. CONSTITUTION:After a flattening process, a flattened layer 5 of a semiconductor wafer 1 is provided also on a dicing section 4, which means that the difference in height between the highest portion and the lowest portion on the semiconductor wafer 1 is smaller than it used to be prior to the formation of the flattened layer 5. A colored layer 6 is provided on a picture element receiving the color concerned, on image sensors other than light-receiving sections, and over the dicing section 4. A first intermediate layer 7, like the flattened layer 5, is provided on the entire semiconductor wafer 1 except over electrode pads sections 3. An overcoat layer 8 is not on the electrode pad sections 3, either.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides a solid-state image sensing device comprising a light receiving section, a charge transfer section, and a transfer control section, which has an electrode pad section, and has a plurality of electrode pads arranged on a semiconductor wafer. A color solid-state image sensor having a dicing area created to separate the solid-state image sensor from adjacent elements when manufacturing the solid-state image sensor, and further comprising a micro color filter element comprising at least a flattening layer and a dyed layer on the solid-state image sensor. Regarding elements.

(Prior Art) A plurality of COD or MO8 type solid-state image sensors are usually fabricated on one semiconductor wafer. A solid-state image sensing device formed by a normal process has a micro color filter attached to the top when used for color. Attachment of micro color filters is generally carried out through the following process.

(1) Planarization step: Coat a resist layer on the wafer, remove light, develop, rinse, and bake. The reason for installing this flattening layer is (, C
Since the surface of the D or MO8 type solid-state imaging device has unevenness steps of several μm, color unevenness will occur if the dyeing process is performed without a flattening layer, so this is prevented.

(2) Dyeing process: Apply a dyeable resist layer, expose, develop, dye, and bake.

(3) Intermediate layer process: The contents of the process are the same as (1).

(4) Dyeing process: (5) Intermediate layer process: (6) Dyeing process: (7) Overcoat layer process: The contents of the process are the same as (1).

In the case of a micro color filter, three colors of blue, green, and red are generally used in the case of a primary color filter, while on the other hand, four colors of cyan, yellow, green, and magenta (or white) are used in the case of a complementary color filter. Between these two or three dyeing steps, an intermediate layer or fixation treatment is performed, and finally an overcoat layer is formed.

(The problem that the invention aims to solve) On the semiconductor wafer, the die cinder part forms the lowest surface), and on the other hand, A which transfers the signal received by the food cell.
/The top of the transfer section is formed on the highest surface. In this case, a step difference of 4 to 5 μm exists between this lowest surface and the highest surface. If the above-described coating process is repeated on a wafer having such steps, for example, if the coating is repeated multiple times using a spinner coat, uneven coating will occur. Uneven coating
It increases as the number of coating steps increases, and for example, at the end of the third dyeing step, it increases to the extent that it can be visually confirmed.

Coating unevenness occurs mainly in the area extending from the die cinder section to the light receiving section.

Due to such coating unevenness, the quality of micro color filters deteriorates, the quality of reproduced television images also deteriorates, some of them become unusable as products, and the product defect rate increases.The object of the present invention is to It is an object of the present invention to provide a color solid-state imaging device that eliminates unevenness in each layer coated in the process of manufacturing a micro color filter, forms a high-quality image, and can be provided at low cost.

(Means and operations for solving the problem) In order to achieve this object, the color solid-state image sensor according to the present invention has the following features. That is, the micro color filter element is removed by etching on the electrode butt part, and the flattened layer of the micro color filter element remains at least on the dicing part.

When forming a micro color filter on a wafer after manufacturing of a solid-state image sensor, a flattening layer, an intermediate layer, and an overcoat layer are applied to the entire surface of the wafer. On the other hand, the dyed layer is also painted over the entire surface, but a color pattern is formed on pixels corresponding to the color in question, and a layer with the color in question is left in areas outside the light-receiving area. However, the bonteindan nod part is removed.

The respective layers coated over the entire surface of the wafer and the dyed layer removed from some of the pixels are removed by etching, especially on the electrode pad portions. These layers allow at least the flattening layer of the micro color filter element to remain as a cured film layer in other parts, especially in the dicing area.

These layers left in the dicing area will not adversely affect the solid-state imaging device. The process applied to the production of the color solid-state image sensor according to the present invention is not limited to on-wafer color filters, but is also effective for producing bonded color filters.

(Description of Examples) The figures are cross-sectional views showing a color solid-state image sensor according to the present invention according to its manufacturing stages. Figure (A) shows a cross section of the semiconductor wafer 1 after the planarization process has been completed. 1
A plurality of solid-state image sensor chips 2 are formed on one wafer 1, and these chips 2 are separated from each other by a dicing area 4. An electrode pad section 3 is provided around each chip 20. Since the flattening layer 5 is also provided in the die cinder region 4, it is clear that the level difference between the highest and lowest parts on the Uni-No-1 is smaller than before the flattening layer 5 was provided. It is clear from this.

The planarization layer 5 can be made by first applying a planarization resist using, for example, a spinner coat, masking the electrode rad portion 3, exposing it to light, developing it, rinsing it, and baking it.

Figure (B) shows the semiconductor wafer 1 after the first dyeing step. This figure (B) and the following figures (C) and figure p) show only a portion of one chip 2 of the wafer 1 on an enlarged scale. The dyeing layer 6 is provided on the image sensor and the dicing section 4 other than the pixels and light receiving sections that receive light of the relevant color.

This dyed layer 6 can be made by exposing a photosensitive liquid such as gelatin, casein, or PVA of the first hue using a spinner coating or a mask, developing it, and dyeing it.

FIG. The intermediate layer process is substantially the same as the planarization layer process.

Figure (D) shows the semiconductor Unino S-1 equipped with a micro color filter that has been completed with an overcoat layer 8. The overcoat layer 8 is also removed only on the electrode notch P portion 3, and its manufacturing process is the same as the planarization process. Further, the second and third dyed layers and the second intermediate layer are provided in the same manner, but each layer can be formed in the same manner as the first dyeing step and the first intermediate layer step.

The present invention is also effective in manufacturing color filters using the following manufacturing process.

Flattening layer coating → Bake (no etching of the electrode pad part. No photolithography process) → First color dyeing layer process (also formed on the electrode pad part) → First intermediate layer process (no photolithography process) → Second color dyeing layer Process → 2nd intermediate layer process → 3rd color dyeing layer process → Oh, 2-coat layer process (no photorin process) → Positive resist coating → Open only on the pad part Oh 7
2-Coat Layer Exposure→Plasma Etching Through the above process, the positive resist serves as a mask during plasma etching, and the overcoat layer dyed layer, intermediate layer, and flattening layer on the electrode knots are etched away. Note that in actual cases, a manufacturing process that does not use an intermediate layer is preferable in order to reduce the thickness of the plasma etched portion.

(Effects of the Invention) According to the color solid-state image sensor according to the present invention, in the process of manufacturing a micro color filter, resist was conventionally left only in the necessary parts of the photodiode 9 in order to reduce the step difference. Resist on the entire surface of the present invention (flattening layer, dyeing layer, intermediate layer).

By changing to a method in which the overcoat layer (overcoat layer) is left (excluding the pad area and some of the pixels), coating unevenness due to steps is greatly reduced, providing a high-quality micro color filter with high Get quality images. Furthermore, even though the manufacturing process is not particularly complex, the defect rate of the products is significantly reduced, so the manufactured products will inevitably be lower priced.

Since the portions of the solid-state image sensor other than the light-receiving portion are covered with the three dyed layers, no light reaches the portions other than the light-receiving portion, and there is no need to form a special anti-flare layer. Therefore, parts for preventing flare can be omitted when constructing an electronic camera, which also contributes to making the device more economical.

[Brief explanation of drawings]

Figures (B), (C), and (D) are cross-sectional views of color solid-state image sensing devices shown according to the manufacturing stages. 1. Wafer, 2. Chip, 3. . . . Electrode pad portion, 4 . . . Dicing area, 5 . . . Flattening layer, 6
...Dyeing layer, 7...Intermediate layer, 8...Overcoat layer. Engraving of the drawings (no changes to the contents) Part l Illustration procedure Nerlj official manuscript (method) July 1985/Zakuchi Patent Office Commissioner Akira Kuroda IF 1, Indication of examples Patent application No. 8 of 1988 / 1931 No. 2, Name of the invention Color solid-state imaging system Ryo 3, Person making the amendment, Case relationship: Tokuko'F Applicant name: (520) Fuji Photo Film Co., Ltd. 4, Agent 6, Increased due to the amendment - Number of inventions 207, Subject of amendment: 1) "Brief explanation of drawings" column 2) of the specification
drawing

Claims (1)

[Claims] (1) A solid-state image sensor consisting of a light-receiving section, a charge transfer section, and a transfer control section has an electrode pad section, and is used to separate adjacent devices when a plurality of solid-state image sensors are manufactured on a semiconductor wafer. In the color solid-state imaging device, the color solid-state imaging device has a dicing area formed and further has a micro-color filter element formed of at least a flattening layer and a dyed layer on the solid-state imaging device, wherein the micro-color filter element is removed on the electrode pad portion. A color solid-state image sensor, characterized in that at least a flattening layer of the micro color filter element remains at least on the dicing part.