JP4356340B2 - Solid-state image sensor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a solid-state image sensor, such as a CCD solid-state image sensor or a CMOS solid-state image sensor.
[0002]
[Prior art]
Solid-state imaging devices such as CCD solid-state imaging devices (CCD image sensors) and CMOS-type solid-state imaging devices (CMOS image sensors) are widely used in, for example, digital cameras and camera-equipped mobile phones.
[0003]
A schematic cross-sectional view of such a solid-state imaging device, for example, a CCD type solid-state imaging device is shown in FIG. 19 (see Patent Document 1).
Note that FIG. 19 shows a cross-sectional view of an element corresponding to one pixel.
The CCD type solid-state imaging device 41 has a light receiving sensor unit 43 formed at a predetermined position in the semiconductor substrate 42, and is transferred to a predetermined position on the semiconductor substrate 42 other than the light receiving sensor unit 43 through a gate insulating film 44. An electrode 45 is formed. A light shielding film 47 is formed on the transfer electrode 45 via an interlayer insulating film 46, and an opening 48 is formed on the light receiving sensor portion 43 by the adjacent light shielding film 47. The amount of light incident on the light receiving sensor unit 43 is controlled by the area of the opening 48.
[0004]
On the light shielding film 47, an interlayer insulating film 49 made of, for example, BPSG (boron / phosphorus / silicate glass) is formed, and a concave surface 50 is formed at a position corresponding to the light receiving sensor portion 43 of the interlayer insulating film 49. . Then, a high refractive index layer 51 made of, for example, a SiN film is formed on the interlayer insulating film 49, and an in-layer lens 52 having the concave surface 50 of the interlayer insulating film 49 as a lens surface is formed on the light receiving sensor portion 43. ing.
In order to collect light on the light receiving sensor unit 43, the refractive index of the upper high refractive index layer 51 is adjusted to be larger than the refractive index of the interlayer insulating film 49.
[0005]
The upper surface of the high refractive index layer 51 is flattened, and a passivation film 53 is formed on the flattened high refractive index layer 51. On the passivation film 53, a color filter 54 having a certain repetitive pattern is formed. The color filter 54 is formed so that one color corresponds to one pixel. In the case of FIG. 19, for example, red (R) is formed correspondingly. Further, an on-chip microlens 55 is formed on the color filter 54 at a portion corresponding to the light receiving sensor unit 43 via an interlayer insulating film (not shown).
[0006]
Pixels having such a configuration are arranged in a matrix to form an imaging region of a CCD solid-state imaging device.
[0007]
[Patent Document 1]
JP 11-297974 A
[0008]
[Problems to be solved by the invention]
By the way, in the CCD type solid-state imaging device 41 as described above, since the width D of the opening 48 of the light receiving sensor unit 43 is formed in the same size in each pixel, the opening area is all the same in each pixel. The sensitivity is all uniform.
Therefore, in the image taken with the camera equipped with such a CCD type solid-state image pickup device 41, the photographed object is copied as it is.
[0009]
Here, it is considered that the CCD type solid-state imaging device 41 is used for various purposes so that a predetermined pattern such as a character or a picture appears in a part of the photographed image.
[0010]
However, as described above, the image captured by the camera equipped with the CCD type solid-state imaging device 41 is captured as it is, so that when a predetermined pattern such as characters and pictures is captured in the captured image, A predetermined pattern must be inserted into a part of the photographed image using, for example, a PC (so-called personal computer).
[0011]
However, for example, when a photograph is taken with a camera-equipped mobile phone and a predetermined pattern is inserted into the photographed image using the camera-equipped mobile phone, not only the image pickup mechanism but also an additional circuit such as an image processing mechanism is included in the mobile phone. It is difficult to incorporate an image processing mechanism in addition to the imaging mechanism in a limited space such as a cellular phone because the configuration of the cellular phone becomes large.
Further, even when considering the power consumption and manufacturing cost of the mobile phone, it is difficult to incorporate the additional circuit into the mobile phone.
[0012]
On the other hand, there is a method in which a predetermined pattern is drawn automatically in front of the lens of the camera so that the predetermined pattern is automatically captured in the captured image. The camera itself will be overwhelmed.
[0013]
In view of the above, the present invention provides a solid-state imaging device capable of copying a predetermined pattern on a captured image without requiring an additional circuit.
[0014]
[Means for Solving the Problems]
  The solid-state imaging device according to the present invention is a solid-state imaging device in which a predetermined pattern is formed on a part of a photographed image, and a light shielding film formed by covering a plurality of light receiving sensor units and at least other than the light receiving sensor unit And a color filter formed in a predetermined repeating pattern over the entire imaging region, the pixel having a condensing lens formed correspondingly on the light receiving sensor unit is arranged in a matrix. The repeated pattern of the color filter that is arranged and formed on some pixels corresponding to the predetermined pattern is formed in a different repeating pattern from the repeated pattern of the color filter formed on pixels other than some pixels.
[0015]
  According to the above-described solid-state imaging device according to the present invention, as a means for forming a predetermined pattern on a part of a photographed image, a repetitive pattern of color filters formed on some pixels corresponding to the predetermined pattern is: It is formed with a repetitive pattern different from the repetitive pattern of the color filter formed on pixels other than some of the pixels. For this reason, it is not necessary to add an additional circuit or a filter to the configuration, and the hue of the predetermined pattern that appears in a part of the photographed image is changed to the target hue by changing the hue of some pixels corresponding to the predetermined pattern. Can be changed.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
  Embodiments of the present invention will be described below with reference to the drawings.
  First, a schematic cross-sectional view of a solid-state image sensor, for example, a CCD solid-state image sensor is shown in FIG.
Note that FIG. 1 shows a cross-sectional view of an element corresponding to one pixel.
  CCD type solid-state image sensor 1The light receiving sensor unit 3 is formed at a predetermined position in the semiconductor substrate 2, and the transfer electrode 5 is formed at a predetermined position on the semiconductor substrate 2 other than the light receiving sensor unit 3 through the gate insulating film 4. Yes. A light shielding film 7 is formed on the transfer electrode 5 via an interlayer insulating film 6, and an opening 8 is formed on the light receiving sensor unit 3 by the adjacent light shielding film 7. The amount of light incident on the light receiving sensor unit 3 is controlled by the area of the opening 8.
[0021]
An interlayer insulating film 9 made of, for example, BPSG (boron / phosphorus / silicate glass) is formed on the light shielding film 7, and a concave surface 10 is formed at a position corresponding to the light receiving sensor portion 3 of the interlayer insulating film 9. . A high refractive index layer 11 made of, for example, a SiN film is formed on the interlayer insulating film 9, and an intralayer lens 12 having the concave surface 10 of the interlayer insulating film 9 as a lens surface is formed on the light receiving sensor unit 3. ing.
In order to collect light on the light receiving sensor unit 3, the refractive index of the upper high refractive index layer 11 is adjusted to be larger than the refractive index of the interlayer insulating film 9.
[0022]
The upper surface of the high refractive index layer 11 is flattened, and a passivation film 13 is formed on the flattened high refractive index layer 11. A color filter 14 is formed on the passivation film 13. The color filter 14 is arranged so that one color corresponds to one pixel. In the pixel shown in FIG. 1, for example, red (R) is arranged correspondingly. Further, an on-chip microlens 15 is formed on the color filter 14 at a portion corresponding to the light receiving sensor unit 3 via an interlayer insulating film (not shown).
[0023]
Pixels having such a configuration are arranged in a matrix, and the imaging region of the CCD solid-state imaging device 1 is configured.
[0024]
In the color filter 14, for example, as shown in FIGS. 2A to 2G, each color is arranged in a fixed repeating pattern.
2A to 2G show, for example, arrangement patterns of primary color filters. 2A shows a Bayer color filter, FIG. 2B shows an interline color filter, FIG. 2C shows a G stripe RB checkered color filter, and FIG. 2D shows a G stripe RB full checkered color filter. 2E shows a color filter with a stripe arrangement, FIG. 2F shows a color filter with an oblique stripe arrangement, and FIG. 2G shows a color filter with a primary color difference arrangement.
[0025]
  Andthe aboveIn particular, the configuration of some pixels corresponding to the predetermined pattern is formed to be different from the configuration of the other pixels.
  That is, as shown in FIG. 3, when it is desired that a character or a picture (for example, the character “Sample”) be captured in a part of the image 23 when the image is taken, a pixel corresponding to the character or picture is displayed as a pixel. It is formed with a configuration different from the other pixels.
[0026]
  First, for example, when the configuration of the condenser lens is differentSolid-state image sensorIs shown in FIG. Specifically, the on-chip microlens 15 has a different size.
  The left side of the drawing shows a cross-sectional view corresponding to one pixel other than the pixels corresponding to the predetermined pattern, and the right side of the drawing shows a cross-sectional view corresponding to one pixel of the pixels corresponding to the predetermined pattern.
  Solid-state image sensorThen, the on-chip microlens 15 is formed large in the pixel corresponding to the portion where the character “Sample” is shown as shown in FIG. Form small. The other parts are the same as those shown in FIG. 1, and the corresponding parts are denoted by the same reference numerals.
  That is, among the “Sample”, for example, an enlarged plan view of the on-chip microlens 15 of the pixel in the vicinity of the “S” portion is shown in FIG. A large on-chip microlens 151 (black portion in the figure) is formed, and a small on-chip microlens 152 (white portion in the figure) is formed in pixels other than the corresponding pixels along the “S” shape.
  In FIG. 5, the case of a pixel corresponding to the letter “S” in “Sample” has been described as an example, but a large on-chip microlens is also applied to pixels corresponding to other characters as in the case described above. 151 is formed.
  As described above, in the pixel corresponding to the character, the on-chip lens 151 larger than the other pixels is formed, so that the amount of received light is increased and the sensitivity can be increased.
[0027]
As described above, in order to form the on-chip microlens 151 that is large only in the pixel corresponding to the predetermined pattern, the resist pattern may be changed only in the pixel corresponding to the predetermined pattern when the on-chip microlens 15 is formed.
[0028]
Hereinafter, a case where the on-chip microlens is enlarged only for pixels corresponding to a predetermined pattern will be described with reference to FIGS.
6 and 7, the left side is a cross-sectional view corresponding to one pixel other than the pixels corresponding to the predetermined pattern, and the right side is a cross-sectional view corresponding to one pixel of the pixels corresponding to the predetermined pattern.
Further, a description will be given from a state in which an on-chip microlens forming material has already been formed on the entire surface including the color filter 14. The parts corresponding to those in FIG.
First, as shown in FIG. 6, a resist layer 20 is formed on the on-chip microlens forming material 19. At this time, the resist layer 20 having a uniform film thickness is formed on both the pixels corresponding to the characters and the pixels other than the pixels corresponding to the characters.
In addition, the resist layer 20 has a small selection ratio with respect to the on-chip microlens forming material 19.
[0029]
Next, a resist mask 21 having a pattern for forming an on-chip microlens is formed from the resist layer 20 by a known lithography technique.
At this time, as shown in FIG. 7, in the resist mask 21, a resist mask 211 having a large pattern is formed in pixels corresponding to the predetermined pattern, and a resist mask 212 having a small pattern is formed in pixels other than the pixels corresponding to the predetermined pattern. Form.
That is, in “Sample”, for example, an enlarged plan view of the resist mask 21 of the pixels around the “S” portion is shown in FIG. In this case, a resist mask 211 having a large pattern is formed, and a resist mask 212 having a small pattern is formed in pixels other than the corresponding pixels along the “S” shape.
In FIG. 8, the pixel corresponding to the letter “S” in “Sample” has been described as an example. However, in the pixels corresponding to other characters as well, a large resist mask 211 is formed in the same manner as described above. Form.
[0030]
Thus, in order to form the resist mask 211 that is large only in pixels corresponding to the predetermined pattern, for example, the resist mask 211 is formed by adjusting the viscosity (fluidity) of the resist layer corresponding to the predetermined pattern or adjusting the exposure time. Can do.
[0031]
Next, using the resist mask 21 as a mask, the on-chip microlens forming material 19 is removed by, for example, isotropic etching.
As a result, as shown in FIG. 4, a large on-chip microlens 151 is formed in pixels corresponding to the predetermined pattern, and a small on-chip microlens 152 is formed in pixels other than the pixels corresponding to the predetermined pattern. .
[0032]
  aboveAccording to the CCD solid-state imaging device 1, a large on-chip microlens 151 is formed in pixels corresponding to a predetermined pattern, and a small on-chip microlens 152 is formed in pixels other than the pixels corresponding to the predetermined pattern. Therefore, only some of the pixels corresponding to the predetermined pattern among the plurality of pixels can change the sensitivity.
  Thereby, a difference in brightness occurs between some pixels corresponding to the predetermined pattern and pixels other than some pixels corresponding to the predetermined pattern, so that only the predetermined pattern is raised. .
  Therefore, when a picture is taken with a camera equipped with such a CCD solid-state imaging device 1, a predetermined pattern (character “Sample”) can be copied on a part of the image 23, as shown in FIG.
  As described above, when a picture is taken, a predetermined pattern can be copied as it is on a part of the image, so that it is not necessary to add an additional circuit, a filter, or the like to the configuration as in the conventional art.
[0033]
  Next, if the configuration of the condenser lens is different,Solid-state image sensorThe form of is shown in FIG. Specifically, this is a case where the size of the in-layer lens is different from the on-chip microlens as described above.
  9 also shows a cross-sectional view corresponding to one pixel other than the pixels corresponding to the predetermined pattern on the left side of the drawing, and a cross-sectional view corresponding to one pixel of the pixels corresponding to the predetermined pattern on the right side of the drawing. Is shown. The other parts are the same as those shown in FIG. 1, and the corresponding parts are denoted by the same reference numerals.
  The above solid-state image sensorAlso in the case of FIG. 5, similarly to the case where the size of the on-chip microlens 15 shown in FIG. 5 is changed, the large intra-layer lens 121 is formed only for the corresponding pixel along the character “Sample”, In other than the corresponding pixels, a small inner lens 122 is formed.
  In this way, in some pixels corresponding to characters, the inner lens 121 larger than pixels other than some pixels corresponding to characters is formed, so that the amount of light received only by the pixels corresponding to the predetermined pattern is increased. To increase the sensitivity.
[0034]
As described above, in order to form the inner lens 12 large only for pixels corresponding to the predetermined pattern, the pixels corresponding to the predetermined pattern are formed when the inner lens 12 is formed, as in the case of the on-chip microlens 15 described above. Only the resist pattern needs to be changed.
[0035]
Hereinafter, FIGS. 10 to 11 show process diagrams in the case where the inner lens is enlarged only for each pixel corresponding to the predetermined pattern.
The left side of the figure shows a cross section of pixels corresponding to the predetermined pattern, and the right side of the figure shows a cross section of pixels other than the pixels corresponding to the predetermined pattern. Further, a description will be given from a state in which an interlayer insulating film 9 (for example, BPSG) is already formed on the entire surface so as to cover the light shielding film 7.
First, as shown in FIG. 10A, a resist layer 20 is formed on the interlayer insulating film 9. At this time, the resist layer 20 having a uniform film thickness is formed on both the pixels corresponding to the characters and the pixels other than the pixels corresponding to the characters.
[0036]
Next, a resist mask 26 having a pattern in which an opening 25 is formed at a position where the inner lens 12 is formed is formed from the resist layer 20 by a known lithography technique.
At this time, as shown in FIG. 10B, the resist mask 26 forms a large opening width D1 in pixels corresponding to characters, and forms a small opening width D2 in pixels other than pixels corresponding to characters.
[0037]
Next, using the resist mask 26 as a mask, the interlayer insulating film 9 is removed by, for example, isotropic etching.
Accordingly, as shown in FIG. 11C, a large concave surface 101 is formed at a position corresponding to the light receiving sensor portion 3 of the interlayer insulating film 9 in the pixel corresponding to the character, and a small concave surface is formed in the pixel other than the pixel corresponding to the character. 102 is formed.
[0038]
Next, as shown in FIG. 11D, the high refractive index material layer 11 (for example, having a higher refractive index than the interlayer insulating film 9 is formed on the entire surface covering the concave surfaces 10 (101, 102) formed in the interlayer insulating film 9. For example, a SiN film) is formed.
As a result, the large intra-layer lens 121 is formed in the pixel corresponding to the character, and the small intra-layer lens 122 is formed in the pixel other than the pixel corresponding to the character.
[0039]
After this, although not shown, the upper surface of the high refractive index layer is flattened, a passivation film is formed on the flattened high refractive index layer, a color filter is formed on the passivation film, and a color filter is formed on the color filter. An on-chip microlens is formed in a portion corresponding to the light receiving sensor portion via an interlayer insulating film.
[0040]
  the aboveAccording to the CCD solid-state imaging device of this form, the large intra-layer lens 121 is formed in the pixels corresponding to the predetermined pattern, and the small intra-layer lens 122 is formed in the pixels other than the pixels corresponding to the predetermined pattern. Of the plurality of pixels, only some of the pixels corresponding to the predetermined pattern can change the sensitivity.
  Thereby, a difference in brightness occurs between some pixels corresponding to the predetermined pattern and pixels other than some pixels corresponding to the predetermined pattern, so that only the predetermined pattern is raised. .
  Therefore, as mentioned aboveSolid-state image sensorSimilarly to the case of FIG. 3, when photographing is performed with a camera equipped with such a CCD type solid-state imaging device, a predetermined pattern (character “Sample”) is copied on a part of the image 23 as shown in FIG. Can do.
  As described above, when a picture is taken, a predetermined pattern can be copied as it is on a part of the image, so that it is not necessary to add an additional circuit, a filter, or the like to the configuration as in the conventional art.
[0041]
  Mentioned aboveSolid-state image sensorThen, all of some pixels corresponding to a predetermined pattern are formed with a large condenser lens (on-chip microlens 15 and in-layer lens 12), and all other pixels are formed with a small condenser lens. However, for example, by changing the size of the condensing lens of the pixels around some of the pixels corresponding to the predetermined pattern, a character such as brightness or darkness is added around the character so that characters appearing in the image can be displayed. It can be rich.
  Even in such a case, when forming the condensing lens, the resist pattern of the pixel corresponding to the predetermined pattern may be changed, and the resist pattern of the surrounding pixels may be changed.
[0042]
  Also mentioned aboveSolid-state image sensorIn FIG. 12, only the pixels corresponding to the predetermined pattern are formed with a large condensing lens. However, as shown in FIG. 12, for example, the curvature of the condensing lens corresponds to some pixels corresponding to the predetermined pattern and the predetermined pattern. It is also possible to make it different from pixels other than some of the pixels. In the case of FIG. 12, an on-chip microlens 152 having a small curvature formed on a pixel other than the pixel corresponding to the predetermined pattern is shown on the left side in the drawing, and the pixel corresponding to the predetermined pattern is formed on the right side in the drawing. An on-chip microlens 151 having a large curvature is shown.
[0043]
In this case, when forming the condensing lens, the curvature can be relatively easily set, for example, if the pattern is a predetermined pattern as a whole, depending on the thickness of the resist layer and the etching amount (etching speed × etching time). Although it can be controlled, it is difficult to change the curvature at random for each pixel.
[0044]
  Also mentioned aboveSolid-state image sensorIn the above description, a CCD type solid-state imaging device including the on-chip microlens 15 and the condenser lens 12 is described as an example.But exampleFor example, the present invention can be applied to a CCD type solid-state imaging device in which the intralayer lens 12 is not formed.
[0045]
In addition, as described above, the condensing lens can be greatly formed only in some pixels corresponding to the predetermined pattern only by changing the resist pattern of only some pixels corresponding to the predetermined pattern. There is no significant change, and the number of steps is small.
[0046]
The size range of the condensing lens is a maximum that does not interfere with the condensing lens of the adjacent pixel. On the other hand, when forming it small, for example, you may make it not form a condensing lens.
In this case, the amount of received light is reduced, the sensitivity is lowered and the image becomes dark.
[0047]
  Next, when the opening state of the light shielding film on the light receiving sensor part is made differentSolid-state image sensorIs shown in FIG.
  In the case of FIG. 13 as well, a cross-sectional view of pixels other than a part of pixels corresponding to a predetermined pattern is shown on the left side of the figure, and a cross-sectional view of a part of pixels corresponding to the predetermined pattern is shown on the right side of the figure. ing.
  Solid-state image sensorIn FIG. 5, only the pixel corresponding to the character “Sample” is formed with a large opening width D3 of the light-shielding film 7 on the light-receiving sensor unit 3, and the light-shielding on the light-receiving sensor unit 3 is formed except for the pixel corresponding to the character. The opening width D4 of the film 7 is formed small.
  Thereby, in the pixel corresponding only to the character, the aperture area can be made larger than the pixel other than the pixel corresponding to the character, and the amount of received light is increased and the sensitivity is increased.
[0048]
As described above, in order to form only the pixels corresponding to the predetermined pattern with a large opening width D3, for example, when forming the light-shielding film 7, only each pixel corresponding to the predetermined pattern is formed as in the case of the condenser lens described above. What is necessary is just to change a resist pattern.
[0049]
Process steps for increasing the opening width D3 only for each pixel corresponding to the predetermined pattern are shown in FIGS.
The left side of the figure shows a cross-sectional view of pixels other than the pixels corresponding to the predetermined pattern, and the right side of the figure shows a cross-sectional view of the pixels corresponding to the predetermined pattern. Further, a description will be given from a state in which the transfer electrode 5 has already been formed at a predetermined position on the semiconductor substrate 2 via the gate insulating film 4 and the interlayer insulating film 6 has been formed to cover the transfer electrode 5.
First, as shown in FIG. 14A, a light shielding film forming material film 29 is formed on the entire surface so as to cover the interlayer insulating film 6. Next, as shown in FIG. 14B, a resist layer 30 is formed on the entire surface so as to cover the light shielding film forming material film 29.
At this time, the resist layer 30 having the same film thickness is formed in the pixels corresponding to the predetermined pattern and the pixels other than the pixels corresponding to the predetermined pattern.
[0050]
Next, as shown in FIG. 15C, a resist mask 32 having a pattern having an opening 31 in the light receiving sensor unit 3 is formed from the resist layer 30 by a known lithography technique.
At this time, the opening 311 of the resist mask 31 is formed large in the pixel corresponding to the character, and the opening 312 of the resist mask 31 is formed small in the pixel other than the predetermined pattern.
[0051]
Next, using the resist mask 31 as a mask, the light shielding film forming material film 29 is etched away by, for example, isotropic etching. As a result, as shown in FIG. 15D, a light shielding film 7 having a predetermined pattern is formed.
At this time, in the pixel corresponding to the character, the light-shielding film 72 having a small protrusion on the light-receiving sensor unit 3 is formed, so that the opening width D1 on the light-receiving sensor unit 3 is increased, and the pixels other than the pixel corresponding to the character are formed. In this pixel, the light shielding film 72 having a large protrusion on the light receiving sensor unit 3 is formed, so that the opening width D2 on the light receiving sensor unit 3 is formed small.
[0052]
Thereafter, although not shown, an interlayer insulating film and a high refractive index layer are sequentially formed on the entire surface covering the light shielding film, and a passivation film is further formed on the high refractive index layer. Then, a color filter is formed on the passivation film, and an on-chip microlens is formed on the color filter at a portion corresponding to the light receiving sensor portion via an interlayer insulating film.
[0053]
  aboveAccording to the CCD type solid-state imaging device, the opening width D3 of the light shielding film 71 on the light receiving sensor unit 3 of the pixel corresponding to the predetermined pattern is formed large, and on the light receiving sensor unit 3 of the pixel other than the pixel corresponding to the predetermined pattern. Since the opening width D4 of the light shielding film 72 is formed small, it is possible to increase the sensitivity of only a part of the pixels corresponding to the predetermined pattern among the plurality of pixels.
  Thereby, a difference in brightness occurs between some pixels corresponding to the predetermined pattern and pixels other than some pixels corresponding to the predetermined pattern, so that only the predetermined pattern is raised. .
  Therefore, as mentioned aboveSolid-state image sensorSimilarly to the case of FIG. 3, when photographing is performed with a camera equipped with such a CCD type solid-state imaging device, a predetermined pattern (character “Sample”) is copied on a part of the image 23 as shown in FIG. Can do.
    As described above, when a picture is taken, a predetermined pattern can be copied as it is on a part of the image, so that it is not necessary to add an additional circuit, a filter, or the like to the configuration as in the conventional art.
[0054]
  Solid-state image sensorIn FIG. 2, the projection width of the light shielding film 7 on the light receiving sensor unit 3 of the pixel corresponding to the predetermined pattern is increased by reducing the protrusion of the light shielding film 7 on the light receiving sensor unit 3. For example, as shown in FIG. 16, the light-shielding film 7 may be formed so as to completely cover the light-receiving sensor unit 3 so that there is no opening.
  In this case, since the light receiving sensor unit 3 is completely covered with the light shielding film 7, the opening area becomes zero and the image becomes dark.
[0055]
  Mentioned aboveSolid-state image sensorAs in the case of, characters appearing in the image with gradations such as brightness and darkness around the characters by changing the opening state of the light shielding film on the light receiving sensor portion around the pixels corresponding to the predetermined pattern. Can be made rich.
  Even in such a case, when forming the light shielding film, the resist pattern of each pixel corresponding to the predetermined pattern may be changed and the resist pattern of each peripheral pixel may be changed.
[0056]
  Also mentioned aboveSolid-state image sensorIn this case, the opening width of the light-shielding film 7 on the light-receiving sensor unit 3 can be increased only by changing the resist pattern of only some pixels corresponding to the predetermined pattern. Therefore, there is little increase in the number of processes without greatly changing the manufacturing process.
[0057]
Next, FIG. 17 shows an embodiment in which the color filter repeat pattern is made different.
FIG. 17A shows an arrangement rule of color filters formed over the entire imaging region, and FIG. 17B shows an arrangement rule of color filters formed on pixels corresponding to a predetermined pattern.
That is, as shown in FIGS. 2A to 2G, various color filters 14 having a constant repeating pattern so that one color corresponds to one pixel in the entire imaging region of the CCD type solid-state imaging device. Is formed.
However, in this embodiment, a color filter 141 having a repetitive pattern different from the color filter 142 having a certain repetitive pattern formed in the entire imaging region is formed in some pixels corresponding to the predetermined pattern. To.
[0058]
For example, as shown in FIG. 17A, the entire imaging area is composed of 4 pixels of Red (red), 8 of Green (green), and 4 of Blue (blue). In the case where the color filter 142 having the arrangement rule (so-called Bayer arrangement) is formed, if it is desired that the predetermined pattern is reddish, red may be increased with respect to the arrangement of the color filter 142. That is, as shown in FIG. 17B, for example, the color filter 141 may be formed with 8 Red (red), 4 Green (green), and 4 Blue (blue).
[0059]
Further, as shown in FIG. 18A, when it is desired to make the predetermined pattern bluish, if the color filter 143 is formed by increasing blue (for example, 3 Red, 6 Green, and 7 Blue). Good.
As shown in FIG. 18B, when it is not desired to emphasize blue in a predetermined pattern, a color filter 144 with reduced blue (for example, 7 for Red, 6 for Green, and 3 for Blue) is formed. That's fine.
[0060]
As described above, in this embodiment, in some pixels corresponding to a predetermined pattern, the color adjustment is performed by increasing or decreasing each color filter according to the color to be emphasized or the color to be suppressed in the predetermined pattern. To be able to.
[0061]
In addition, in this way, in order to change the repetitive pattern of the color filter only for some pixels corresponding to the predetermined pattern, when the color filter is formed as in the case of the condensing lens and the light shielding film described above, the predetermined pattern It is sufficient to change the resist pattern only for pixels corresponding to.
[0062]
The color filter 14 has been described by taking a primary color filter as an example, but a complementary color filter can also be used.
As described above, even when a complementary color filter is used, in the same manner as in the present embodiment, in some pixels corresponding to a predetermined pattern, the arrangement of each color filter is set according to the hue of the target predetermined pattern. A modified color filter may be formed.
[0063]
According to the CCD solid-state imaging device of the present embodiment, in some pixels corresponding to a predetermined pattern, the color filter 141 in which the arrangement of each color filter is changed according to the target color of the predetermined pattern is formed. Thus, it is possible to change the hue of the predetermined pattern.
Thereby, the predetermined pattern appearing in the photographed image can be adjusted to the target color.
[0064]
In the embodiment described above, the character “Sample” has been described as an example of the predetermined pattern. However, for example, in the case of a picture such as a character, the pixel corresponding to the character is assigned to the pixel corresponding to the character. It is only necessary to form the opening state on the condensing lens and the light receiving sensor portion or the repeated pattern of the color filter so as to be different from each other.
[0065]
In this case, for example, in the color filter formed on the corresponding pixel along the line representing the character, for example, in the portion corresponding to the shaded portion, the arrangement of each color filter is changed so as to become dark, and the portion without the shadow By changing the arrangement of each color filter so that the portion corresponding to is brighter, it is possible to add a gradation to the shade of the character appearing in the image to make it dark.
[0066]
In the case where the size or curvature of the condensing lens is different, for example, in the condensing lens formed on the corresponding pixel along the line representing the character, for example, corresponding to a shadowed portion, as in the case described above. For example, the condensing lens is made small so that it becomes dark, and the condensing lens is made large so that it becomes bright in the part corresponding to the part without shadows. You can add a gradation to make the character rich.
[0067]
Further, even when the opening state of the light shielding film of the light receiving sensor unit 3 is changed, the opening width of the light shielding film 7 is reduced (narrow) in, for example, a shadowed portion in a part of the corresponding pixels along the line representing the character. ) By forming the opening width of the light-shielding film large (wide) in the portion corresponding to the portion without the shadow, the character can be made glossy.
[0068]
  Mentioned aboveSolid-state image sensorIn some pixels corresponding to a predetermined pattern, when the configuration of the condensing lens is different, when the opening state of the light shielding film on the light receiving sensor portion is different, or when the repeated pattern of the color filter is different However, for example, in a pixel corresponding to a predetermined pattern, a plurality of these can be combined.
[0069]
  Also mentioned aboveSolid-state image sensorIn the pixel corresponding to the predetermined pattern, the condensing lens, the light shielding film, and the color filter formed on the semiconductor substrate are different from each other. The configuration of the sensor unit (for example, photoelectric conversion efficiency) can be made different.
  However, in this case, it is necessary to make the configuration of the light receiving sensor unit corresponding to the predetermined pattern different in the initial stage of manufacture of the solid-state imaging device, which causes a problem that it becomes difficult to change the predetermined pattern, for example.
[0070]
Further, in the above-described embodiment, the description has been given with reference to characters and pictures as the predetermined pattern. However, the predetermined pattern includes, for example, a symbol, a mark, a logo, and the like.
[0071]
In the above-described embodiment, the CCD solid-state image sensor has been described as an example. However, the present invention can also be applied to other solid-state image sensors, for example, a CMOS solid-state image sensor.
[0072]
The solid-state imaging device of the present invention is suitable for use in a camera-equipped mobile phone that requires limited space, power consumption, manufacturing cost, and the like, but can also be used in, for example, a digital camera. .
[0073]
The solid-state imaging device of the present invention is suitable for use in, for example, a camera (for example, a surveillance camera) used for security technology.
That is, forgery and the like can be prevented, for example, by making the predetermined pattern appearing in the image when the image is taken into a dense pattern that cannot be discerned visually but can be discriminated by a machine.
[0074]
The present invention is not limited to the above-described embodiment, and various other configurations can be taken without departing from the gist of the present invention.
[0075]
【The invention's effect】
According to the solid-state imaging device of the present invention, it is possible to make a predetermined pattern appear in a part of an image when shooting.
Further, by changing the repeated pattern of the color filter only for a part of pixels corresponding to the predetermined pattern, it is possible to change the hue of the predetermined pattern appearing in a part of the image to a target color.
[0076]
Thus, there is no need to add an additional circuit such as an image processing circuit or a filter on which a predetermined pattern is drawn, and a solid-state imaging device capable of copying the predetermined pattern to a part of a photographed image is provided. it can.
[0077]
In addition, since a predetermined pattern can be copied onto a part of an image in this way, it can be used for various purposes such as the security field.
[Brief description of the drawings]
[Figure 1]Solid-state image sensorIt is a schematic sectional drawing corresponding to 1 pixel.
FIGS. 2A to 2G are plan views showing arrangement rules of respective color filters. FIGS.
FIG. 3 is a plan view showing an image including a predetermined pattern.
FIG. 4 shows a case where the configuration of the condenser lens of the pixel corresponding to the predetermined pattern is changed.Solid-state image sensorIt is a schematic sectional drawing which shows.
FIG. 5 is an enlarged plan view showing a configuration of a condensing lens around a pixel corresponding to a predetermined pattern.
FIG. 6 is a process diagram (part 1) illustrating a method of forming a condensing lens.
FIG. 7 is a process diagram (part 2) illustrating a method of forming a condenser lens.
FIG. 8 is an enlarged plan view showing a configuration of a resist mask around a pixel corresponding to a predetermined pattern.
FIG. 9 shows a case where the configuration of the condensing lens of the pixel corresponding to the predetermined pattern is changed.Solid-state image sensorIt is a schematic sectional drawing which shows.
10 is a process diagram (part 1) illustrating the manufacturing method of the embodiment of FIG. 9; FIG.
11A to 11D are process diagrams (part 2) illustrating the manufacturing method of the embodiment of FIG.
FIG. 12 is a schematic cross-sectional view showing a case where the curvature of the condenser lens is changed.
FIG. 13 shows a case where the opening state of the light shielding film of the pixel corresponding to the predetermined pattern is changed.Solid-state image sensorIt is a schematic sectional drawing which shows.
14A to 14B are process diagrams (part 1) showing the manufacturing method of the embodiment of FIG.
15 is a process diagram (part 2) illustrating the manufacturing method of the embodiment of FIG. 13; FIG.
FIG. 16 is a schematic cross-sectional view showing another form of the opening state of the light shielding film.
FIGS. 17A and 17B are plan views showing an embodiment of a color filter arrangement rule for pixels corresponding to a predetermined pattern; FIGS.
FIGS. 18A and 18B are plan views showing other forms of arrangement rules of color filters of pixels corresponding to a predetermined pattern. FIGS.
FIG. 19 is a schematic cross-sectional view corresponding to one pixel of a conventional solid-state imaging device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... CCD type solid-state image sensor, 2 ... Semiconductor substrate, 3 ... Light-receiving sensor part, 4 ... Gate insulating film, 5 ... Transfer electrode, 6 ... Interlayer insulating film, 7 ..Light-shielding film, 8 ... opening, 9 ... interlayer insulating film, 10 (101,102) ... concave surface, 11 ... high refractive index layer, 12 (121,122) ... inside layer Lens, 13 ... Passivation film, 14 (141, 142) ... Color filter, 15 (151, 152) ... On-chip microlens, 19 ... On-chip forming material, 20, 30, ..Resist layer, 21 (211 and 212)... Resist mask, 23... Image, 29.

Claims (2)

In a solid-state imaging device in which a predetermined pattern is formed on a part of a photographed image,
Imaging in which pixels having a plurality of light receiving sensor units, a light shielding film formed so as to cover at least other than the light receiving sensor unit, and a condensing lens formed corresponding to the light receiving sensor unit are arranged in a matrix. Has an area,
A color filter formed in a constant repeating pattern is arranged over the entire imaging region,
In that the predetermined pattern is a repeating pattern of a color filter formed on a part of a pixel corresponding are formed in a different repeating pattern than the repetitive pattern of color filters formed on pixels other than pixels the part A solid-state imaging device. The solid-state imaging device according to claim 1, wherein the predetermined pattern is a character or a picture.

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