JPH02285672A - Solid-state image sensing device and its manufacture - Google Patents

Abstract

PURPOSE:To facilitate the improvement of a protective function to the surface of a solid-state image sensing device, the prevention of irregular reflection due to bubbles in a molding resin and the like by a method wherein the device is manufactured into a structure, wherein filter layers having a plurality of hues obtained by dying a photosensitive resin with dyes, transparent intermediate layers and a protective layer are laminated in order on photodetecting parts on a substrate to form color filter parts and a glass plate is adhered on the upper surfaces of the color filter parts. CONSTITUTION:A solid-state image sensing device is manufactured into a structure, wherein filter layers 11, 9 and 13 having a plurality of hues obtained by dying a photosensitive resin with dyes, transparent intermediate layers 10 and 12 and a protective layer 14 are laminated in order on photodetecting parts 4 on a substrate 1 to form color filter parts and a glass plate 22 is adhered on the upper surfaces of the color filter parts. Moreover, in case the solid-state image sensing device like the above structure is manufactured, the manufacture is carried out so as to go through a process for forming laminatedly the above layers 10 and 12 and 14 by a coating means, a process for adhering the plate 22 on the upper surfaces of the color filter parts with the above layers 11, 9 and 13 laminated on them and a process for removing a region other than a region adhered with the plate 22 by dry etching.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a solid-state image sensor in which color filter layers of a plurality of hues are formed in stages on a light receiving portion on a substrate, and a method for manufacturing the same.

[Prior art]

In general, as a solid-state image sensor equipped with this type of color filter layer, the one disclosed in, for example, Japanese Unexamined Patent Publication No. 19885-1985 is well known as a conventional example. In this conventional example, a detailed explanation is given in the fourth method (corresponding to the fourth embodiment) as an example in which color filter layers of a plurality of hues are formed stepwise, and the specific structure thereof is described in the same publication. 9th of
10. As shown in FIG. However, the manufacturing method and process, that is, the manufacturing process including the electrode part and scribe line of the semiconductor wafer, etc., are not explained in detail. Explain an example. In FIG. 4, reference numeral 1 denotes a silicon substrate such as a semiconductor wafer, on which a large number of regions of solid-state image sensing devices 3 are cut along scribe lines 2 to form - chips, and each A large number of light receiving sections 4 and electrode sections 5 are mounted in the area of the image sensor 3, respectively. and,
The surface of the silicon substrate 1 is subjected to surface treatment as shown in FIGS. 5A to 5E, and colored filter treatment is performed as shown in FIGS. 6A to 6K. 5. In Figures 5 (^) to ([), the light-receiving parts 4 are recessed adjacent to each other as shown in Figure (A), and the holes in the light-receiving parts 4 that are recessed are filled in as shown in Figure (B). The photosensitive transparent resin layer 6 is spin-coded as shown in FIG. By processing with (D), the photosensitive transparent resin layer 6 of each light receiving part 4 remains as shown in FIG. Then, a photosensitive transparent resin similar to that described above is spin-coded onto the flat surface to form a base layer 8, and the surface is further flattened. In this case, the electrode portion 5 is exposed by removing the base layer 8 for wiring, that is, wire bonding, and the scribe line 2 portion is formed by cutting each solid-state image sensor 3 into a chip. At this time, the cut resin powder scatters and adheres to the entire surface, making it difficult to remove it, so the photosensitive transparent resin on the scribe line, that is, the base layer 8, is removed and exposed. After the groundwork has been done in this way, the 6th (^)~(
K) A colored filter layer is formed in the steps shown in the figure. That is, gelatin, which will become the first filter layer 9 as shown in the figure (B), is spin-coded on the silicon substrate 1 that has been subjected to the surface treatment shown in the figure (A), and the first filter layer 9 is spin-coded. 9 is generally red, so if you use a pattern mask that leaves only that part corresponding to the position where the red filter layer 9 is to be formed, expose and develop it as shown in Figure (C). Only the filter layer 9 corresponding to the red color of the light receiving section 4 remains. This remaining filter layer 9
is dyed by a known dyeing method, and then the intermediate layer 10 is spin-coded with a photosensitive transparent resin as shown in Figure (D), and the electrode portion 5 and the scribe line 2 are removable. When exposed and developed using a pattern mask, only the portions corresponding to the electrode portions 5 and the scribe line 2 are removed, and the entire red filter layer 9 is covered, as shown in the figure. An intermediate layer 10 is formed. Through steps similar to the above, the green filter layer 11 and the intermediate layer 12 are sequentially formed as shown in Figures (F) to (H), and furthermore, as shown in Figures (1) to (B), a blue color filter layer 11 and an intermediate layer 12 are formed in sequence. A filter layer 13 and a surface protective layer 14 are sequentially formed, and each adjacent light receiving section 4 has a filter layer 9 of a different hue.
11.13 is an insulating base layer 8゜intermediate layer 10.1
By cutting the semiconductor wafers, which are laminated in stages through the wafers 2 and on which the protective layer 14 is formed, into chips along the scribe line 2, a substantial solid-state image sensor with a color filter is formed. . As shown in FIG. 7, the solid-state imaging device cut into chips is connected by bonding wires 16 between each electrode portion 5 and a plurality of lead frames 15, and then the solid-state imaging device is cut into chips. The image sensor, all of the wires 16, and a part of the lead frame 15 are molded and bonded with transparent resin 17 to complete a solid-state image sensor as a single product.

[Problem to be solved by the invention]

In the solid-state imaging device in the conventional example, the protective layer 14 formed on the surface is made of the same resin as the base layer 8 and the intermediate layer 10, 12, so it has poor smoothness and chemical resistance, and the surface Not only does it have problems with its protection function, but
Another problem is that when a chip-shaped solid-state image sensor is molded with a transparent resin after being connected to a lead frame, bubbles are generated and diffused reflection increases. Moreover, even in the conventional manufacturing method, in order to expose the portions corresponding to the electrode portions 5 and the scribe lines 2, an exposure and development step is performed each time when forming each filter layer, intermediate layer, and protective layer. Since these steps are carried out individually, not only is the number of steps large and the workability is poor, but also the exposure and development steps each time result in the vicinity of the electrode section 5 and scribe line 2 being in the state shown in FIG. 8. That is, by performing the exposure and development process each time, the base layer 10. The intermediate layer 12 and the protective layer 14 are gradually thinned at the boundary portions where each electrode portion and the scribe line are located, and other portions are raised, resulting in distortion as a whole. Therefore, in the conventional example, there are serious problems in improving the surface protection function, preventing diffused reflection due to bubbles in the mold resin, improving productivity, and eliminating distortion. [Means for Solving the Problems] As a specific means for solving the problems in the conventional example, the present invention provides a light-receiving section on a substrate with filter layers of a plurality of hues made of photosensitive resin dyed with dyes and a transparent intermediate layer. A color filter section is formed by sequentially laminating layers and a protective layer, and a solid-state image sensor is formed by pasting a glass plate on the top surface of the color filter section, and a light-receiving section on the substrate is dyed with a photosensitive resin. A method for manufacturing a solid-state imaging device by sequentially laminating filter layers of a plurality of hues, a transparent intermediate layer, and a protective layer, the method comprising: forming the transparent intermediate layer and the protective layer by laminating them using a coating means; , comprising means for adhering a glass plate to the upper surface of the color filter portion on which the filter layers of the plurality of hues are laminated, and means for removing an area other than the area to which the glass plate is adhered by dry etching. The present invention provides a method for manufacturing a solid-state image sensor characterized by the presence of the glass plate, which not only further improves the surface protection effect, but also prevents the generation of bubbles and bubbles because the molding resin is molded avoiding the glass plate. There is no need to worry about diffused reflection caused by
Furthermore, in the lamination formation of the intermediate layer and the protective layer, pattern matching and exposure and development processing can be omitted, so work efficiency is improved, and a dry etching process is performed at the final stage to remove the color filter portion covered with the glass plate. Since the laminated resin is removed outside the area, the terminal portion and scribe line can be easily exposed.

Example 1 Next, the present invention will be explained in more detail with reference to the illustrated examples. In order to facilitate understanding, parts that are the same as those in the conventional example are given the same reference numerals and details thereof are omitted. In FIG. 1, reference numeral 1 denotes a silicon substrate such as a semiconductor wafer, on which a large number of regions of solid-state image sensing devices 3 are cut along scribe lines 2 to form - chips, and each A large number of light receiving sections 4 and electrode sections 5 are mounted in the area of the image sensor 3, respectively. and,
Each of the adjacent light-receiving parts 4 is filled with a photosensitive transparent resin layer 6 for filling holes, and a base layer 8 is provided thereon to make the whole flat, and filter layers 11 of different hues are formed on the base layer. .9 and 13 are laminated in stages through insulating intermediate layers 10 and 12, and the upper protective layer 14 is laminated, which is the same as the conventional example. In the present invention, in order to further impart smoothness to the surface of the color filter section 21 in the protective layer 14 and to protect the surface, the scriber is attached to the glass plate 22 integrally. The structure is such that there is no resin base layer, intermediate layer, or protective layer above the line 2 and the electrode section 5. Further, regarding each of the filter layers, the first filter layer 1
1 is green, the second filter layer 9 is red, and the third
The third filter layer 13 is formed in blue. Furthermore, the second
The layer and third layer remain the same even if they are switched. A method for manufacturing the solid-state image sensor having the above configuration will be explained based on FIGS. 2(A) to 2(1). First, as shown in Figure (A), each light receiving part 4 of the silicon substrate 1 is filled with a photosensitive transparent resin layer 6 to make its surface substantially flat, and then the conventional example and Similarly, the base layer 8 is formed by spin-coding a photosensitive transparent resin. In this case, the difference from the conventional example is that the electrode portion 5
The scribe line 2 is also covered with the base layer 8, and the exposure and development steps are not performed. The photosensitive transparent resin used therein is a negative type photosensitive resin (trade name: rsANBo AR-GJ, manufactured by Sanpo Chemical Research Institute).
It is formed with a thickness in the range of about 4,000 to 6,000 people. After the base treatment is completed in this manner, the same latin that will become the first filter layer 11 is spin-coded in the step shown in FIG. The layer thickness in this case is approximately io, oo
o ~ 13,000 people. When exposed and developed using a pattern mask that exposes only that portion corresponding to the position where the first filter layer 11 is to be formed, the light-receiving portion is exposed as shown in FIG. Only the filter layer 11 corresponding to green color 4 remains. When this remaining filter layer 11 is dyed green using a known dyeing method, the thickness of the layer becomes approximately 15,000 to 16,000. Next, as shown in the figure (D), the intermediate layer 10 is spin-coated with a photosensitive transparent resin to cover the electrode portion 5 and the scribe line 2 as described above. In this case, the thickness of the intermediate layer is also in the range of approximately 4,000 to 6,000 layers. After forming the first green filter layer 11 and the intermediate layer 10, the intermediate layer 10 is subjected to the same process as above, i.e., spin code, patterning exposure, as shown in the figure. , a second red filter layer 9 is formed by a developing and dyeing process, and an intermediate layer 12 is further formed by spin-coding as shown in FIG. In this case as well, the thickness of the red filter layer 9 after dyeing is approximately 15 mm.
000 to 16,000 people, and the thickness of the middle @ 12 is in the range of about 4,000 to 6,000 people as described above, and it is also the same that the electrode part 5 and the scribe line 2 are covered as they are. Furthermore, by the same process as described above, as shown in CG), a blue filter layer 13 is formed on the upper part of the intermediate layer 12 corresponding to the light receiving part 4, and a protective layer 14 is sequentially formed on the upper part of the blue filter layer 13. Specifically, filter layers 11, 9, and 13 of different hues are provided on each adjacent light-receiving section 4, respectively, and an insulating base layer 8 is provided.
．． A semiconductor wafer is obtained in which the intermediate layers 10 and 12 are laminated in stages, the protective layer 14 is formed on top of the intermediate layer 10, and the electrode portion 5 and the scribe line 2 are completely covered with the insulating resin layer. It will be done. The blue filter layer 13 is formed to have a thickness of about 4,000 people,
After dyeing, the thickness of the protective layer 14 is approximately 6,000 mm, and in order to reduce the overall level difference between the previously laminated filter layers of each color and the intermediate layer, the protective layer 14 has a thickness of approximately 10.000 to 11.0 mm.
．． The thickness of the semiconductor wafer is made to be approximately 1,000 mm thick to absorb partial differences in level, thereby making the surface of the semiconductor wafer substantially flat. Next, above the protective layer 14 and the color filter section 2
As shown in figure (H), a glass plate 22 having a thickness of about 1 mm is adhered to the top of the glass plate 1, and as shown in figure (1), dry etching is performed to form a glass plate. The intermediate layer 12° 10 and the base layer 8 are sequentially etched and removed from the protective layer 14 exposed in the area where the plate 22 is not present, that is, in the area other than the color filter part 21, and the electrode part 5 and the scribe line 2 are exposed. become a state. Then, by cutting the semiconductor wafer into chips along the scribe line 2, a solid-state image sensor with a color filter is formed. As shown in FIG. 3, the solid-state image sensor with a color filter cut into chips has the following characteristics as in the conventional example:
Each electrode part 5 and a plurality of lead frames 15 are connected by bonding wires 16, and then molded with transparent resin 17.The difference from the conventional example is that the upper surface of the glass plate 22 This method solves the problem of bubbles caused by the mold resin by exposing the glass plate and molding the entire wire 16 and part of the lead frame 15 from the edge of the glass plate to the side surface. Furthermore, this mold resin
Since it does not cover the upper surface of 2, it does not contribute to the light receiving function at all, and therefore there is no need to use transparent mold resin. Furthermore, as described above, the base layer, intermediate layer, and protective layer are removed by dry etching in the final stage over the entire area other than the color filter section 21, so the resin used for each of these layers is expensive. This eliminates the need to use photosensitive resin. Effects of the Invention As explained above, the solid-state image sensor according to the present invention includes filter layers of a plurality of hues made of photosensitive resin dyed with dye, a transparent intermediate layer, and a protective layer in the light receiving part on the substrate. Since the color filter section is formed by sequentially laminating layers and a glass plate is attached to the top surface of the color filter section, the surface of the solid-state image sensor becomes smooth, and since the surface layer is inorganic, it is chemical resistant. It has excellent properties and has the excellent effect of significantly improving its protective function. In addition, the method for manufacturing a solid-state image sensor according to the present invention includes sequentially stacking filter layers of a plurality of hues made of photosensitive resin dyed with dye, a transparent intermediate layer, and a protective layer on a light-receiving part on a substrate to form a solid-state image sensor. A method for manufacturing an image sensor, the method comprising: forming the transparent intermediate layer and the protective layer by laminating them using a coating means; and placing a glass plate on the top surface of the IC color filter section in which the filter layers of the plurality of hues are laminated. By adopting a process including a means for adhering the glass plate and a means for removing the area other than the area to which the glass plate is adhered by dry etching, pattern matting and exposure are not required in the lamination formation of the intermediate layer and the protective layer. Since development processing can be omitted, work efficiency is improved, and at the final stage, a dry etching process is performed to remove the resin on the electrode parts and scribe lines.
It has excellent workability, and the presence of the glass plate makes the entire surface flat, making it possible to manufacture a solid-state imaging device without distortion.

[Brief explanation of drawings]

FIG. 1 is an enlarged cross-sectional view showing only the main parts of the solid-state image sensor according to the present invention, and FIGS. 2 (^) to (I) are sequential schematic illustrations of the manufacturing process of the color filter layer according to the present invention 3 is a schematic sectional view of the solid-state imaging device of the present invention connected to a lead frame and molded with resin, and FIG. 4 is a part of a general semiconductor wafer. FIGS. 5(A) to 5(E) are schematic plan views showing enlarged views of v- in FIG.
Corresponding to the cross section along line V, FIGS. 6(A) to 6(K) are enlarged cross-sectional views of only the main parts, sequentially schematically showing the base treatment steps in the conventional example. Corresponding to the cross section along the line ■-■, an enlarged cross-sectional view of only the main parts sequentially schematically showing the manufacturing process of the color filter layer according to the conventional example. Fig. 8 is a schematic cross-sectional view showing the electrode part and the vicinity of the scribe line of the conventional example in a further enlarged manner.1...・Silicon substrate 2...Scribe line 3...Image sensor area 4...Light receiving part 5...Electrode part 6...Polling resin 7... ... Pattern mask 8 ... Base layer 9 ... Red filter layer 10.12 ... Intermediate layer 11 ... Green filter layer 13 ...
Blue filter layer 14...Protective layer 21.
...Color filter section 22 ...Glass plate patent applicant Toppan Printing Co., Ltd.

Claims (3)

[Claims] (1) A color filter section is formed by sequentially laminating filter layers of a plurality of hues made of photosensitive resin dyed with dye, a transparent intermediate layer, and a protective layer on the light receiving section on the substrate, and A solid-state image sensor with a glass plate attached to the top surface. (2) The above-mentioned claim (1) wherein the thickness of the glass plate is approximately 1 mm.
) solid-state imaging device. (3) A method for manufacturing a solid-state imaging device by sequentially laminating filter layers of a plurality of hues made of a photosensitive resin dyed with a dye, a transparent intermediate layer, and a protective layer on a light receiving portion on a substrate, the method comprising: means for forming the transparent intermediate layer and the protective layer by laminating them using a coating means; means for adhering a glass plate to the upper surface of the color filter section on which the filter layers of the plurality of hues are laminated; and means for adhering the glass plate. 1. A method of manufacturing a solid-state imaging device, comprising: removing a region other than the removed region by dry etching.