JP2007079154A - Forming method for color filter and manufacturing method for solid-state imaging element using forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a forming method for a color filter in which pattern formation of high precision is achieved to prevent color mixing and make the color filter thin, and also to provide a solid-state imaging element which has high sensitivity and high reliability even when the element is made thin and fine at high level. <P>SOLUTION: The forming method for the color filter includes a stage of applying a filter material, and a stage of etching the filter material through a resist pattern as a mask, and thereby the filter material is patterned. The stage of etching includes a stage of etching using reactive gas consisting principally of oxygen (O<SB>2</SB>) containing a carbon (C) compound as etching gas. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for forming a color filter and a method for manufacturing a solid-state imaging device using the same, and more particularly to a method for forming a thin and flat color filter that prevents color mixing.

  In recent years, demands for higher resolution and higher sensitivity have been increasing in solid-state imaging devices, and the number of imaging pixels has been increasing to more than gigapixels. Under such circumstances, in order to obtain high resolution without increasing the chip size, it is necessary to reduce the area per unit pixel and achieve high integration. Furthermore, the substrate (silicon substrate) on which the solid-state imaging device is built is mounted by further stacking lenses on the filter. For this reason, not only the color filter and photoelectric conversion unit for each color, but also the positional accuracy between the lens and the photoelectric conversion unit is important, and the distance, that is, the distance in the height direction, is only for the purpose of ensuring the positional accuracy in the manufacturing process. It is also an important factor in terms of sensitivity (photoelectric conversion efficiency) during use.

  The color filter is manufactured as follows. First, a color resist, for example, a B (blue) color filter material is applied on a flat surface, patterned by exposure and development, and then fixed by heat treatment or ultraviolet irradiation, so that the B color filter Form. Next, a colored resist, for example, a G (green) color filter material is applied onto the B color filter and the flat surface, exposed and developed for patterning, and then fixed by heat treatment or ultraviolet irradiation. Thus, a G color filter is formed. Finally, on the B and G color filters and the flat surface, for example, a colored resist, which is an R (red) color filter material, is applied, patterned by exposure and development, and then subjected to heat treatment or ultraviolet irradiation. By fixing, an R color filter is formed.

  In this method, since the photosensitive group is contained, the density of the colored group is small, and since the patterning is performed by the wet processing by development, a residue containing the colored group may adhere.

  Therefore, in recent years, a method of patterning a color filter by dry etching using a resist pattern as a mask has been proposed (see, for example, Patent Document 1 below).

In this method, the filter shape to be obtained greatly depends on the etching selectivity between the resist and the filter material.
For example, as shown in FIG. 16A, when a resist pattern R1 is formed on the surface of the color filter material 50R and etching is performed by dry etching using the resist pattern R1 as a mask, a reverse taper shape is obtained as shown in FIG. There are many cases. Each figure is an enlarged explanatory view of a main part.
As shown in FIG. 16C, the opening formed in this manner is filled with the color filter material 50G of the second color, so there is a concern of color mixing between the first color and the second color. It has come to be.
That is, a part of the pattern of the color (G) or red (R) color filter material to be formed next to the pattern of the B color filter on the blue (B) color filter pattern formed earlier. May overlap. If the G or R color filter material is formed in this state, a part of the G or R color filter formed later remains on the upper part of the adjacent B color filter. It becomes a factor to inhibit.

JP-A-5-183140

  As described above, a method of patterning a color filter by dry etching using a resist pattern as a mask has attracted attention. However, in this method, the obtained filter shape depends greatly on the etching selectivity between the resist and the filter material. Color mixing between the first color and the second color has become a serious problem.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method for forming a color filter that enables highly accurate pattern formation, prevents color mixing, and realizes thinning.
It is another object of the present invention to provide a solid-state imaging device that prevents color mixing, is thin, and has high sensitivity and high reliability even when highly miniaturized.

The present invention is a method for forming a color filter that includes a step of applying a filter material and a step of etching the filter material using a resist pattern as a mask, and the step of etching comprises an etching gas. And a step of etching using a reactive gas mainly containing oxygen (O ₂ ) containing a carbon (C) compound.
With this configuration, the etching selectivity between the resist and the filter material can be adjusted by etching using a reactive gas mainly containing oxygen (O ₂ ) containing a carbon (C) compound as an etching gas. And a pattern of filter material with a desired profile can be formed. In addition, since the color filter material is patterned by dry etching, it is possible to form a high-precision pattern with steep pattern edges without forming a residue on the surface of the substrate or attaching a residue. It becomes.

  Further, the present invention includes the method for forming a color filter, wherein the carbon compound is oxygenated carbon (CO).

According to the present invention, in the color filter forming method, the etching step includes a step of performing etching while changing a mixing ratio of oxygen and CO.
With this configuration, the etching selectivity can be adjusted by changing the mixing ratio of oxygen and CO, and a desired profile can be obtained.

In the color filter forming method according to the invention, the etching step includes a step of etching using a C _X H _Y F _Z- based gas as an etching gas.

In addition, the present invention includes the method for forming a color filter, wherein the etching gas is a step of etching using a mixed gas of CH ₂ F ₂ gas and CH ₃ F.

According to the present invention, in the method for forming a color filter, a step of forming a first color filter by forming a color filter material of a first color on a substrate surface and patterning the material by dry etching to form an opening. And forming a second color filter material on the surface of the substrate on which the first color filter is formed, and planarizing the surface on which the second color filter material is formed. The step of forming the first color filter includes adjusting the composition of the etching gas and patterning so that the pattern edge is perpendicular to the substrate surface. Including what is included.
With this configuration, even when the color filter material of the first color adheres to the upper layer by the flattening step, it can be surely removed and the remaining can be prevented. The level difference between the color filters of different colors can be reduced, and color mixing can be prevented and the thickness can be reduced.

According to the present invention, in the method for forming a color filter, the step of forming the first color filter includes a step of forming a photosensitive resist pattern by photolithography on the surface of the substrate on which the color filter material of the first color is formed. Including a step of forming, and a step of patterning the color filter material of the first color by anisotropic etching using the photosensitive resist pattern as a mask.
With this configuration, high-accuracy patterning can be performed, so that a highly reliable color filter can be formed.

  According to the present invention, in the color filter forming method, the first color filter material includes a material having a photosensitive group content of 20% or less.

  This method reduces the content of unnecessary photosensitive groups when used as a filter, so that the content of colored groups can be increased, the overall film thickness can be reduced, and the amount of light can be reduced even during miniaturization. Loss can be reduced, and a highly sensitive element can be formed.

  In the color filter forming method of the present invention, the first color filter material includes a pigment content of 80% or more.

  By this method, since the content of the colored group can be increased, the overall film thickness can be reduced, and the loss of light amount can be reduced even during miniaturization, and a highly sensitive element can be formed. Become.

According to the present invention, in the color filter forming method, the color filter is formed on the substrate on which the solid-state imaging device is formed.
With this configuration, it is possible to form a thin solid-state imaging device that has no color mixing and is highly reliable.

According to the present invention, the pattern edge of the color filter of each color can be made vertical (steep), the pattern accuracy can be improved, and color mixing can be suppressed.
Furthermore, the sensitivity can be improved by reducing the thickness of the color filter layer.
In addition, it is possible to improve the stains and unevenness associated with the color filter pigment adhesion.
Further, color mixing of the color filter can be prevented and the thickness can be reduced, and a thin and highly sensitive solid-state imaging device can be provided.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
The method for forming a color filter described in the present embodiment is used, for example, for manufacturing a solid-state imaging device.

(Embodiment 1)
In the present embodiment, the color filter material is applied, and etching is performed using a material in which the mixing ratio of oxygen and CO is changed as an etching gas. The mixing ratio of oxygen and CO The etching selectivity is adjusted by changing, and a color filter pattern having a vertical pattern edge is formed.

  FIG. 1 is a cross-sectional view of a solid-state imaging device in which a color filter is formed by the method of Embodiment 1 of the present invention, and FIG. 2 is a schematic plan view. 1 is a schematic cross-sectional view taken along line AA in FIG.

  As shown in FIG. 1, in this solid-state imaging device, the color filter 50 is made of a resin material having a photosensitive group content of 0 above the photodiodes 30 so that the photodiodes 30 face each photodiode 30. High-precision patterns obtained by forming the boundary surface of each color by patterning by dry etching with the etching selectivity adjusted by changing the mixing ratio of oxygen and CO as etching gas through photolithography Has been. In this color filter, a red color filter 50R (not shown), a green color filter 50G, and a blue color filter 50B are arranged on the lower flattening film 74 so as to correspond to each photodiode 30. Each pattern edge is formed to be vertical, and the surface is a flat surface. In FIG. 2, reference numerals (R, G, B) indicating the color filters formed above the photodiodes 30 are attached to the photodiodes 30. As shown in enlarged views of the main part in FIGS. 3A to 3C, the pattern edge is perpendicular to the surface.

  Others have a usual structure, but prior to the description of the method of forming the color filter, the solid-state imaging device will be described first. In the solid-state imaging device used here, photodiodes 30 as photoelectric conversion units are arrayed on the surface of an n-type silicon substrate 1, and signal charges generated in the photodiodes 30 are arranged in the column direction (Y in FIG. 2). The charge transfer section 40 for transferring in the direction) is formed by meandering between a plurality of photodiode rows composed of the plurality of photodiodes 30 arranged in the column direction. Then, the odd-numbered photodiode rows are formed so as to be shifted in the direction of approximately half the array pitch of the photodiodes 30 arranged in the column direction with respect to the even-numbered photodiode rows.

  The charge transfer unit 40 includes a plurality of charge transfer channels 33 formed in the column direction of the surface portion of the silicon substrate 1 corresponding to each of the plurality of photodiode columns, and a charge transfer formed in the upper layer of the charge transfer channel 33. It includes an electrode 3 (first layer electrode 3a, second layer electrode 3b) and a charge readout region 34 for reading out charges generated in the photodiode 30 to the charge transfer channel 33. The charge transfer electrode 3 has a meandering shape extending in the row direction (X direction in FIG. 2) as a whole between a plurality of photodiode rows composed of a plurality of photodiodes 30 arranged in the row direction. . Here, the charge transfer electrode 3 has a single layer electrode structure in which a second layer electrode is formed on the first layer electrode via an interelectrode insulating film and is flattened by CMP, but is not limited to a single layer electrode structure. A two-layer electrode structure in which a part of the first layer electrode is covered with the second layer electrode may be used.

  As shown in FIG. 1, a p well layer 1P is formed on the surface of the silicon substrate 1, an n region 30b for forming a pn junction is formed in the p well layer 1P, and a p region 30a is formed on the surface. The photodiode 30 is configured, and the signal charge generated in the photodiode 30 is accumulated in the n region 30b.

  On the right side of the photodiode 30, a charge transfer channel 33 composed of an n region is formed with a slight distance. A charge readout region 34 is formed in the p-well layer 1P between the n region 30b and the charge transfer channel 33.

A gate oxide film 2 is formed on the surface of the silicon substrate 1, and a first electrode 3 a and a second electrode 3 b are formed on the charge readout region 34 and the charge transfer channel 33 via the gate oxide film 2. The An interelectrode insulating film 5 is formed between the first electrode 3a and the second electrode 3b. A channel stop 32 made of a p ⁺ region is provided on the right side of the vertical transfer channel 33, and is separated from the adjacent photodiode 30.

  An insulating film 6 such as a silicon oxide film and an antireflection layer 7 are formed on the charge transfer electrode 3, and an intermediate layer 70 is further formed thereon. Of the intermediate layer 70, 71 is a light shielding film, 72 is an insulating film made of BPSG (borophosphosilicate glass), 73 is an insulating film (passivation film) made of P-SiN, and 74 is a flattening film under a filter made of transparent resin or the like. It is. The light shielding film 71 is provided except for the opening of the photodiode 30. A color filter and a microlens 60 are provided above the intermediate layer 70. Between the color filter and the micro lens 60, an on-filter planarizing film 61 made of an insulating transparent resin or the like is formed.

  In the solid-state imaging device according to the present embodiment, signal charges generated in the photodiode 30 are accumulated in the n region 30b, and the accumulated signal charges are transferred in the column direction by the charge transfer channel 33, and the transferred signals are transferred. The charge is transferred in the row direction by a horizontal charge transfer path (HCCD) (not shown), and a color signal corresponding to the transferred signal charge is output from an amplifier (not shown). In other words, on the silicon substrate 1, a solid-state imaging device unit that is a region including a photoelectric conversion unit, a charge transfer unit, an HCCD, and an amplifier, and a peripheral circuit that is a region where peripheral circuits (PAD unit and the like) of the solid-state imaging device are formed. Are formed to constitute a solid-state imaging device.

Next, the manufacturing process of the above-described solid-state imaging device will be described.
First, the manufacturing process before forming the color filter will be described.
Impurities are introduced into the surface of the n-type silicon substrate 1 to form a p-well layer 1P, a charge transfer channel 33, a charge readout region 34, a channel stop layer 32, and the like, and then a gate oxide film 2 is formed. Subsequently, a first conductive film constituting the first layer electrode 3a is formed on the gate oxide film 2, and patterning is performed to form the first layer electrode 3a and peripheral circuit wiring. Next, an insulating film 5 made of a silicon oxide film is formed around the first layer electrode 3a, and a second conductive film constituting the second layer electrode 3b is formed thereon. Next, the second conductive film 3b is planarized by CMP and patterned to form the second layer electrode 3b. Next, after forming the insulating film 6 so as to cover these charge transfer electrodes 3, the n region 30b and the p region 30a in the photodiode region are formed, and the light shielding film is opened to the light receiving region in the photodiode region. 71 is formed. Next, an insulating film 72 is formed and planarized by high temperature reflow.

Next, after forming a contact hole in the upper part of the peripheral circuit of the insulating film 72, a metal material is formed and patterned to form a bonding pad (not shown). Then, a passivation film 73 made of a silicon nitride film is formed by a CVD method, and the passivation film on the bonding pad is selectively etched away to form an opening to expose the bonding pad. Thereafter, sintering is performed in an inert gas atmosphere containing H _2, and then a planarizing film having a thickness of 0.5 to 2.0 μm is formed by spin coating or scan coating. Here, in order to avoid confusion with other planarization films, this planarization film is referred to as an under-filter planarization film 74. The manufacturing process so far is a usual method. As the planarizing film 74 under the filter, a resist material transparent to visible light (for example, C series manufactured by FUJIFILM Electronics Materials Co., Ltd.) is used.

Next, the manufacturing process of the color filter will be described in detail with reference to FIGS.
These are views showing each manufacturing process of the color filter of the present embodiment, in which (a) is a cross-sectional view, (b) is a plan view, and (a) is an a-a view of (b). It is sectional drawing. In the plan view, the solid-state imaging device is illustrated as being rotated 45 degrees with respect to the X direction from the state of FIG. In each figure (b), the red color filter 50R is marked with "R", the green color filter 50G is marked with "G", and the blue color filter 50B is marked with "B". In this embodiment, a CMP process for planarization is performed, but since the resist is used as a polishing stop layer, the polishing rate for the resist is about 2: 1 in the CMP process as each color filter material for RGB. Use materials. In the present embodiment, “B” corresponds to the first color, and “R” and “G” correspond to the second color and the third color. In each plan view, the lower layer than the passivation film 73 is omitted.

  First, as shown in FIGS. 4A and 4B, an under-filter flattening film 74 is formed on the passivation film 73, and then, as shown in FIGS. Among the filter materials, the B color filter material having the slowest polishing rate by CMP is applied so as to have a film thickness of 0.5 to 2.0 μm. This color filter material does not contain a photosensitive group.

  Thereafter, as shown in FIGS. 6A and 6B, a resist pattern R1 for forming a blue color filter pattern is formed by photolithography. Here, in FIG. 6B, which is a plan view, the resist pattern R1 covers the region that becomes the blue color filter, and the blue color filter material 50B (B) is otherwise exposed. (Here, as the resist pattern R1, for example, FH-6400L manufactured by FUJIFILM Electronics Materials Co., Ltd. is used, and as the color filter material, C series such as SG-7103L manufactured by FUJIFILM Electronics Materials Co., Ltd. is used).

Thereafter, as shown in FIGS. 7A and 7B, reactive ion etching (RIE), which is anisotropic dry etching, is performed using the resist pattern R1 as a mask to form a blue color filter material pattern. To do. Etching gas at this time, oxygen and a mixed gas of CO, resist and etching selectivity of the color filter material is 1 or more and becomes as the composition ratio of oxygen O _2: CO = _1: at 3 adjust. Here, in FIG. 7B, which is a plan view, the resist pattern R1 covers the region to be the blue color filter, and the rest is the under filter flattening layer 74 exposed.

  Then, the resist pattern R1 is ashed to form a blue color filter 50B (FIGS. 8A and 8B). Here, in FIG. 8B, which is a plan view, the pattern of the blue color filter B is formed, and the others are in a state in which the under-filter flattening layer 74 is exposed.

    Next, the red color filter material R is applied so as to have a film thickness of 0.5 to 2.0 μm. This color filter material does not contain a photosensitive group (FIGS. 9A and 9B). In FIG. 9B, which is a plan view, the blue color filter B pattern is covered with a red color filter material, and the entire surface is a red color filter layer R.

  Then, CMP is performed using the pattern of the blue color filter 50B as a polishing stopper layer to flatten the red color filter material. The R color filter material is formed to fit tightly between the B color filters 50B. In this step, a red color filter 50R is formed (FIGS. 10A and 10B).

  Thereafter, as shown in FIGS. 11A and 11B, a resist pattern R2 for forming a red color filter pattern is formed by photolithography. Here, in FIG. 11B, which is a plan view, the resist pattern R2 covers the regions to be blue and red color filters, and the red color filter material 50R (R) is otherwise exposed.

Thereafter, as shown in FIGS. 12A and 12B, reactive ion etching (RIE), which is anisotropic dry etching, is performed using the resist pattern R2 as a mask to form a red color filter material pattern. To do. In other words, here is a step of exposing the under-filter flattening film 74 in the region where the green color filter is to be formed. Here, in FIG. 12B, which is a plan view, the resist pattern R2 covers the regions to be red and blue color filters, and the underlying filter under-planar planarization layer 74 is exposed. The etching gas used here is a mixed gas of oxygen and CO, and the composition ratio is oxygen O ₂ : CO = 1: 3 so that the etching selectivity ratio between the resist and the color filter material is 1 or more. adjust.

  Then, the resist pattern R2 is ashed to form a red color filter 50R (FIGS. 13A and 13B). Here, in FIG. 13B, which is a plan view, the pattern of the red and blue color filters R and B is formed, and the underlying under-filter flattening layer 74 is exposed in the region where the green color filter is formed. It has become.

  Next, a green color filter material G is applied so as to have a film thickness of 0.5 to 2.0 μm. This color filter material does not contain a photosensitive group (FIGS. 14A and 14B). Here, in FIG. 14B, which is a plan view, the pattern of the red and blue color filters R and B is covered with a green color filter material, and the entire surface is a green color filter layer G. .

  Then, CMP is performed using the pattern of the blue color filter 50B as a polishing stopper layer, and the green color filter material is flattened to form the green color filter 50G (FIGS. 15A and 15B). The green color filter material G is formed so as to fit tightly between the red color filter 50R of the blue color filter 50B.

  By this CMP process, the color filter surface of each color is flat, and a highly accurate color filter pattern can be formed without residue.

  Then, on this color filter, a resist material transparent to visible light (for example, C series manufactured by FUJIFILM Electronics Materials Co., Ltd.) is applied so as to have a film thickness of 0.5 to 2.0 μm. A chemical film 61 is formed. Thereafter, a microlens 60 is formed on the planarizing film 61 by an etching method, a melt method, or the like, thereby forming a solid-state imaging device as shown in FIG.

  As described above, according to the manufacturing method of the present embodiment, a resist pattern formed by photolithography is used as a mask, a mixed gas of oxygen and CO is used as an etching gas, and an etching selectivity ratio between the resist and the color filter material is used. Since the composition ratio is adjusted to be oxygen: CO = 1: 3 so as to be 1 or more and dry etching is performed by RIE, a color filter pattern having a vertical pattern edge can be obtained. Further, it can be composed of only a material necessary as a filter component such as a coloring group without using a photosensitive group, and a high-precision pattern can be formed. Further, the height from the surface of the planarizing film 74 of the color filter can be increased. Since it can be made lower than before, the solid-state imaging device can be made thinner. As a result, a margin for obliquely incident light is widened, and a highly sensitive solid-state imaging device can be manufactured. In addition, color mixing can be prevented.

  In addition, when a pigment-dispersed color filter material is used as the color filter material, a residue is generated at the time of washing with water after forming the pattern of the color filter material, which adheres to the color filters of other colors, Although this is a factor that degrades optical characteristics, particularly image quality, according to the present embodiment, the above residue can also be removed by CMP processing, so that image quality degradation can be prevented.

  In addition, the color filter obtained by the method of the present embodiment has a vertical section with a steep boundary between adjacent color filters, and the surface thereof is substantially flattened. It is also possible to form the microlens 60 directly on the color filter surface without forming it. According to this configuration, the solid-state imaging device can be further thinned, the manufacturing process can be reduced by one step, and a high-sensitivity solid-state imaging device can be manufactured at low cost.

  In this embodiment, the CMP process is performed using the B color filter 50B as a stopper. However, the CMP process may be performed without using the stopper. In this case, by adjusting the processing time, the thickness of the R color filter 50R and the G color filter 50G at a position higher than the height from the surface of the planarizing film 74 of the B color filter 50B becomes 50 nm or less. Thus, the CMP process may be performed. This 50 nm is a value in a range that is acceptable as a step. In this case, the order of forming the color filters is not limited to that described above, and can be changed as appropriate.

  In this embodiment, the CMP process is performed after the R color filter 50R and the G color filter 50G are formed. However, the present invention is not limited to this. For example, after forming the R color filter 50R, a CMP process is performed to remove the R color filter 50R at a position higher than the height from the surface of the planarizing film 74 of the B color filter 50B. After the G color filter 50G is formed, a CMP process may be performed to remove the G color filter 50G at a position higher than the height of the B color filter 50B from the surface of the planarizing film 74. .

  In the present embodiment, the blue color filter 50B is used as the polishing stopper layer, but it is not limited to blue. For example, if the polishing rate of the R color filter material can be the slowest among the RGB color filter materials, the R color filter 50R may be formed first and this may be used as a polishing stopper layer. If the polishing rate of the G color filter material can be the slowest among the RGB color filter materials, the G color filter 50G may be formed first and this may be used as the polishing stopper layer.

  In this embodiment, the solid-state imaging device having a configuration in which photodiodes are arranged in a honeycomb shape has been described. However, the present invention is not limited thereto, and a configuration in which a plurality of photodiodes are arranged in a square lattice shape is described. The present invention can also be applied to other solid-state imaging devices.

  In this embodiment, an RGB primary color filter is used as an example, but the present invention can also be applied to cyan, magenta, and yellow complementary color filters.

(Embodiment 2)
In the first embodiment, a mixed gas of oxygen and oxygen carbide is used as an etching gas. However, in this embodiment, a mixed gas of oxygen gas and CH ₂ F ₂ is used, and the composition ratio is oxygen O ₂ : CH _2. Etching was performed such that the etching selectivity was 1 or more by setting F ₂ = 1: 2. Here, the etching selection ratio may be adjusted by changing the composition ratio between the initial stage and the latter stage of etching.

  In this manner, as in the first embodiment, a color filter is formed that is divided into blue, red, and green with high accuracy and the pattern edges are formed perpendicular to the substrate surface.

  The color filter forming method of the present invention can form a thin color filter layer in which a pattern edge is formed perpendicular to the substrate surface, so that it can be made thinner, and an electronic device such as a mobile phone. This is useful as a solid-state imaging device.

1 is a schematic cross-sectional view of a solid-state imaging device according to Embodiment 1 of the present invention. 1 is a schematic plan view of FIG. Explanatory drawing which shows the formation method of the color filter of this Embodiment 1. It is a figure which shows the manufacturing process of the color filter of this Embodiment 1, (a) is sectional drawing, (b) is a top view. It is a figure which shows the manufacturing process of the color filter of this Embodiment 1, (a) is sectional drawing, (b) is a top view. It is a figure which shows the manufacturing process of the color filter of this Embodiment 1, (a) is sectional drawing, (b) is a top view. It is a figure which shows the manufacturing process of the color filter of this Embodiment 1, (a) is sectional drawing, (b) is a top view. It is a figure which shows the manufacturing process of the color filter of this Embodiment 1, (a) is sectional drawing, (b) is a top view. It is a figure which shows the manufacturing process of the color filter of this Embodiment 1, (a) is sectional drawing, (b) is a top view. It is a figure which shows the manufacturing process of the color filter of this Embodiment 1, (a) is sectional drawing, (b) is a top view. It is a figure which shows the manufacturing process of the color filter of this Embodiment 1, (a) is sectional drawing, (b) is a top view. It is a figure which shows the manufacturing process of the color filter of this Embodiment 1, (a) is sectional drawing, (b) is a top view. It is a figure which shows the manufacturing process of the color filter of this Embodiment 1, (a) is sectional drawing, (b) is a top view. It is a figure which shows the manufacturing process of the color filter of this Embodiment 1, (a) is sectional drawing, (b) is a top view. It is a figure which shows the manufacturing process of the color filter of this Embodiment 1, (a) is sectional drawing, (b) is a top view. Schematic showing the material composition of the color filter of the conventional example

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 N-type silicon substrate 2 Gate oxide film 3a 1st electrode 3b 2nd electrode 5 Interelectrode insulating film 6 Insulating film 7 Antireflection layer 60 Micro lens 61 Planarizing film 71 Light shielding film 72 Insulating (BPSG) film 73 Passivation film 74 Flattening films 50B, 50R, 50G Color filters

Claims (10)

Applying a filter material;
Etching the filter material using a resist pattern as a mask,
A method of forming a color filter for patterning the filter material,
The etching process is a method for forming a color filter, which is an etching process using a reactive gas mainly containing oxygen (O ₂ ) containing a carbon (C) compound as an etching gas. A method for forming a color filter according to claim 1,
The method for forming a color filter, wherein the carbon compound is oxygenated carbon (CO). A method for forming a color filter according to claim 1 or 2,
The color filter forming method, wherein the etching step is a step of performing etching while changing a mixing ratio of oxygen and CO. A method for forming a color filter according to claim 1,
The etching step is a method for forming a color filter, which is a step of etching using a C _X H _Y F _Z- based gas as an etching gas. A method for forming a color filter according to claim 4,
The method for forming a color filter, wherein the etching gas is a step of etching using a mixed gas of CH ₂ F ₂ gas and CH ₃ F. A method for forming a color filter according to any one of claims 1 to 5,
Forming a color filter material of the first color on the surface of the substrate and patterning it by dry etching to form an opening, thereby forming a first color filter;
Forming the color filter material of the second color on the surface of the substrate on which the first color filter is formed;
Flattening a surface on which the color filter material of the second color is formed to form a second color filter;
Forming the first color filter comprises:
A method of forming a color filter, comprising a step of adjusting a composition of the etching gas and patterning so that a pattern edge is perpendicular to a substrate surface. A method for forming a color filter according to claim 6,
The step of forming the first color filter includes a step of forming a photosensitive resist pattern by photolithography on the surface of the substrate on which the color filter material of the first color is formed.
Forming a color filter material of the first color by anisotropic etching using the photosensitive resist pattern as a mask. A method for forming a color filter according to claim 7,
The method for forming a color filter, wherein the first color filter material has a photosensitive group content of 20% or less. A method for forming a color filter according to claim 7,
The method for forming a color filter, wherein the first color filter material has a pigment content of 80% or more. Using the method for forming a color filter according to any one of claims 1 to 9,
A method for manufacturing a solid-state imaging device, wherein a color filter is formed on a substrate on which the solid-state imaging device is formed.

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