JPH0754363B2 - Color filter peeling method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a color filter peeling method, and more particularly to a color filter peeling method that does not adversely affect a substrate and its attached components. .

<Prior Art> Conventionally, as a method for forming a color filter on a substrate such as a solid-state image sensor or a glass plate, a “dyeing method” is generally known.

A method of manufacturing a color filter by this dyeing method will be described with reference to FIG. 2 (a).
In such a case, the flat layer 16 is formed by coating a resin having excellent transparency, flatness, and adhesiveness with respect to the irregularities on the surface of the solid-state imaging device 14, if necessary. Then, a dyeable resist is coated, exposed and developed to pattern a desired dyeing area, and the pattern area is dyed with a dye having a predetermined spectral characteristic to form a colored resin layer 11. Next, a resin having a dye-proof property is coated, exposed and developed to form the intermediate layer 13.

After that, the steps after the dyeable resist coating are repeated, and all the colored resin layers 11, 11 ′, 11 ″ and the intermediate layers 13, 13 ′ are formed.
After forming the colored resin layers 11, 11 ′ and 11 ″, a color filter 17 is manufactured by coating a transparent resin and providing an overcoat layer 12 to protect the colored resin layers 11, 11 ′ and 11 ″. 11, 11 ', 11 ", intermediate layers 13, 13', and overcoat layer 12.

However, in recent years, color filters are required to have high reliability and accuracy, so that uneven coating of resist, uneven development,
At present, the yield in the color filter manufacturing process is extremely low due to stains due to uneven dyeing and adhesion of dust.

Therefore, when the inconveniences such as the unevenness and the scratches occur, the solid-state image pickup device (for example, charge coupled device:
Hereinafter, it is desirable to peel the color filter from a substrate such as a CCD) and reuse it.

As the peeling method, conventionally known are an acid treatment method using concentrated sulfuric acid and the like, and a method of immersing the whole body in a basic aqueous solution such as sodium hydroxide and potassium hydroxide. These treatment methods can easily peel off the color filter, but it is difficult to reuse all of them in order to erode the CCD surface or dissolve the aluminum wiring.

Further, in JP-A-61-148402, a peeling method of irradiating with ultraviolet rays and then immersing in an organic solvent such as dimethyl sulfoxide or cyclohexanone heated to 100 to 150 ° C. for 5 to 20 minutes is further disclosed. In the 62-124174 publication, the substrate is 250
After heating to ~ 300 ℃, polyamines such as ethylenediamine and 1,2-propanediamine at 10 ~ 120 ℃ at 10 ~ 120 ℃
A peeling method of dipping for a minute is known. These have a problem that the color filter cannot be peeled off from the substrate surface of the CCD with sufficient reproducibility.

<Problems to be Solved by the Invention> An object of the present invention is to solve the above problems and provide a method for removing a color filter that does not adversely affect the substrate and its accessories.

<Means for Solving the Problems> The present invention is a method for removing a color filter, in which a color filter on a solid-state image sensor is ashed using oxygen plasma or the like, and ultrasonic cleaning is performed in pure water. .

Further, when a flattening layer made of transparent resin is formed under the color filter, ashing using oxygen plasma of the color filter, ultrasonic cleaning, and then ashing are performed again to remove the flattening layer. It is a method of removing the filter.

In addition, instead of oxygen plasma, plasma is a mixed gas of oxygen and CF ₄ , or ozone gas is sprayed while the substrate is heated to 100 ° C. to 300 ° C., which is a peeling method in which ashing is performed.

<Operation> As described above, the color filter is ashed by using oxygen plasma, and the residue generated by the ashing process can be easily removed by performing ultrasonic cleaning in pure water, and the silicon can be removed in a short time. The color filter can be peeled off without damaging the solid-state imaging device on the substrate.

Furthermore, if a mixed gas of oxygen and CF ₄ is used as the ashing gas, the ashing rate can be increased and the ashing residue can be reduced. In addition, the substrate is 100 ℃ to 3
By heating to 00 ° C. and spraying ozone gas to perform ashing, electrical damage due to plasma can be eliminated. Therefore, the peeling method of the present invention can be applied to an element that cannot be plasma-treated.

When a flattening layer is provided on the surface of a solid-state image sensor using a transparent resin and a color filter is formed on the flattening layer,
First, the color filter is ashed and processed, ultrasonic cleaning is performed in pure water to remove the residue, and then the ashing process is performed again to remove the flattening layer on the solid-state image sensor. The color filter can be peeled off without hindering the ashing of the flattening layer by the ashing residue generated from.

<Example 1> An example of a method for manufacturing and a method for removing a solid-state image sensor with a color filter used in this example is shown in Fig. 1 (a),
An explanation will be given using (b).

10% by weight on the silicon substrate on which the solid-state image sensor 4 is formed
Staining photoresist consisting of an aqueous solution of gelatin containing ammonium dichromate was spin coated to a film thickness of 1.5 μm, and an i-line reduction projection exposure system (Nikon Corporation) was used.
Was used for exposure and development to form a predetermined pattern.
Then, it was immersed in a dyeing solution, washed with water and dried to form a colored resin layer 2. Examples of the dye include 1) Red dye such as Suminol Sealing Scarlet G (trade name of Sumitomo Chemical Co., Ltd.) 2) Examples of green dye include Suminol Sealing Brilliant Green 5G (Sumitomo Chemical Brand name) manufactured by K.K. Co., Ltd. 3) As a blue dye, for example, Kayanol Sealing Blue GW (trade name manufactured by Nippon Kayaku Co., Ltd.) and the like are known.

Further, in order to protect the colored resin layer 1 from dyeing with other dyes, a negative transparent photoresist FVR (manufactured by Fuji Chemical Industry Co., Ltd.) was applied, exposed and developed to form the intermediate layer 3. After forming all the colored resin layers 1, 1 ′, 1 ″ and the intermediate layers 3, 3 ′ with the red dye, the green dye, and the blue dye, the colored resin layer 1,
Negative type transparent photoresist FVR to protect 1 ′, 1 ″
(Fuji Pharmaceutical Co., Ltd.) was applied, exposed and developed to form an overcoat layer 2 [FIG. 1 (a)], and a color filter 7 was prepared.

The solid-state imaging device 4 with the color filter 7 was set in a parallel plate type plasma ashing device, and the color filter 7 was ashed with oxygen plasma. The processing conditions are O ₂
100 SCCM, 1.0Torr, Rf power 300W, processing time is 30 minutes. Then, it was immersed in pure water and subjected to ultrasonic cleaning for 10 minutes [Fig. 1 (b)].

As a result, the color filter 7 could be peeled off without damaging the surface of the solid-state imaging device 4, the wiring, or the like. The electrical damage to the solid-state image pickup element 4 was at a level without any problem.

<Example 2> The solid-state imaging device with a color filter manufactured in the same manner as in Example 1 was set in the same ashing device, and the enzyme and CF ₄ were added.
The color filter was ashed with the mixed gas. Processing conditions are O ₂ 100 SCCM, CF ₄ 20SCCM, 0.5Toor, Rf power 30
It is 0 W and the processing time is 10 minutes. Then, Example 1
Washing was performed in the same manner as in.

Also in this example, the color filter could be peeled off without damaging the solid-state image sensor, and the treatment could be performed in a shorter time than in Example 1.

<Embodiment 3> This embodiment will be described in detail with reference to FIGS.

A negative transparent resist FVR (manufactured by Fuji Chemical Industry Co., Ltd.) was applied on the silicon substrate on which the solid-state imaging device 14 was formed, and a flattening layer 16 was formed on the surface of the solid-state imaging device 14. Then
The same operation as in Example 1 was performed to produce the color filter 17 on the solid-state image sensor 14 [see FIG. 2 (a)].

The solid-state image sensor 14 with the color filter 17 is mounted on an ozone ashing apparatus OA-2400 (Chlorine Engineers Co., Ltd.).
The color filter 17 was ashed. The processing conditions are O ₂ 41 / min (ozone concentration 8000ppm), temperature 200.
C, treatment time 30 minutes. After that, cleaning was performed in the same manner as in Example 1 [see FIG. 2 (b)]. Further, the flattening layer 16 was removed by treating for 15 minutes with an ozone ashing device [see FIG. 2 (c)].

As a result, the color filter 17 and the underlying flattening layer 16 could be peeled off without damaging the solid-state imaging device 14.

<Effects of the Invention> According to the present invention, the color filter can be peeled off from the solid-state imaging device substrate on which the color filter is formed, which has been difficult to recover in the past, without damaging the device. As a result, by separating the color filter from the substrate with a defective color filter and forming the color filter again, it is possible to reuse the solid-state image sensor with a defective color filter and reduce the cost of the solid-state image sensor with a color filter. be able to.

[Brief description of drawings]

1 (a) and 1 (b) show an embodiment of the color filter peeling method of the present invention, and FIGS. 2 (a) to 2 (c) show another embodiment of the color filter peeling method of the present invention. Is. 11 ', 1 "... Colored resin layer 2 ... Overcoat layer 33' ... Intermediate layer 4 ... Solid-state image sensor 5 ... Light receiving part 7 ... Color filter 1111 ', 11" ... Colored resin layer 12 ... … Overcoat layer 1313 ′ …… Intermediate layer 14 …… Solid-state image sensor 15 …… Light receiving part 16 …… Planarization layer 17 …… Color filter

Claims (4)

[Claims] 1. A method for removing a color filter on a solid-state image pickup device, comprising: ashing the color filter with oxygen plasma, and then performing ultrasonic cleaning in pure water. 2. A method of separating a flattening layer on a solid-state image pickup device from a color filter, wherein the color filter is ashed with oxygen plasma, ultrasonically cleaned in pure water, and then flattened again in oxygen plasma. A method for peeling a color filter by ashing and removing a layer. 3. The method of stripping a color filter according to claim 1, wherein ashing is performed by plasma composed of a mixed gas of oxygen gas and CF ₄ gas instead of oxygen plasma. . 4. The method according to claim 1, wherein ozone gas is blown onto the solid-state image pickup device with a color filter heated to 100 to 300 ° C. instead of oxygen plasma, and ashing is performed. How to peel off the color filter.