JPH10229181A - Solid-state image-pickup apparatus and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid-state image-pickup apparatus and manufacture thereof which corrects shading, without applying micro-scaling to a microlens array. SOLUTION: This apparatus, having light receiving rections 1 for forming pixels and microlenses 2 arranged at a first and second pitches P equal to each other on an imaging region, comprises microlenses 2a disposed at every predetermined no. of pixels from the center of the imaging region to the periphery at second pitches which is reduced by reducing the width by W', thereby shifting stepwise more greatly the microlenses 2 at the more peripheral positions on the imaging region, in the imaging region center direction with respect to the photodetectors 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a solid-state imaging device capable of correcting shading and a method of manufacturing the same.

[0002]

2. Description of the Related Art In recent years, as the size and weight of a video camera or the like using a solid-state imaging device have been reduced, the exit pupil distance of a camera optical system has been significantly reduced.

FIG. 15 shows a main part of a conventional solid-state imaging device. As shown in the figure, a light receiving section 1 and a vertical transfer section 6 are provided alternately on a semiconductor substrate 7, and a light shielding film 4 for preventing light from entering the vertical transfer section 6 is provided with a vertical transfer section. 6 is formed so as to cover the vertical transfer electrode 5 provided on the substrate 6. The light-shielding film 4 is opened on the light-receiving portion 1, and microlenses 2 are formed corresponding to each light-receiving portion in order to efficiently converge incident light on the opening 8 of the light-receiving portion 1. . Reference numeral 3 denotes a color filter formed between the light receiving unit 1 and the microlens 2 so as to correspond to each light receiving unit.

As shown in FIG. 16, when the exit pupil distance d of the camera optical system (the distance from the aperture A of the camera lens to the light receiving section 1) is long, the micro lens 2 is not disposed even in the periphery of the imaging area. The incident light L condensed at the point enters the opening 8 of the light receiving section 1. However, when the exit pupil distance d is short, as shown in FIG.
In particular, at the end portion in the x-axis direction (hereinafter, referred to as the horizontal direction), the incident angle of the incident light L on the microlens 2 becomes larger than when the exit pupil distance d is long, so that the incident light that cannot be accommodated in the opening 8 is large. The generation of a component, so-called "vignetting" of the incident light L occurs, and the incidence rate into the opening decreases. As a result, the sensitivity is reduced in the periphery of the imaging region, and when viewed on the imaging screen, so-called “shading” occurs in which the luminance is reduced in the periphery of the screen. FIG. 18 shows an output waveform of one horizontal scan showing this state. In the figure, a broken line indicates an output waveform when shading occurs in the peripheral portion, and a solid line indicates an output waveform when shading in the peripheral portion is corrected. As shown by the broken line, when shading occurs, the output signal Ve at the peripheral portion is considerably lower than the output signal Vo at the central portion.

As a measure against such shading,
JP-A-1-213079 and JP-A-6-140
No. 609 discloses that the pitch P ′ of the microlenses is made smaller than the pitch P of the light receiving unit 1 by performing micro-scaling on the microlens array centering on the center of the imaging area as shown in FIG. It has been proposed to gradually shift the microlenses 2 from the corresponding light receiving unit 1 toward the center of the imaging region as the distance from the center of the imaging region toward the periphery increases. By shifting the micro lens 2 around the imaging region toward the center of the imaging region in this manner, the “eclipse” of incident light at the periphery of the imaging region is reduced, and shading is reduced as shown by the solid line in FIG. Will be corrected. Further, depending on the camera optical system, the exit pupil position may behave as if it is located on the rear surface of the solid-state imaging device. In such a case, the microlens is used as shown in FIG. Japanese Unexamined Patent Publication No.
No. 40609 teaches.

Further, in the above-mentioned Japanese Patent Application Laid-Open No. Hei 6-140609, as shown in FIG. 21, the shift amount of the color filter 3 formed between the light receiving section 1 and the microlens 2 is determined by the shift amount of the microlens 2. It is disclosed that by making the size smaller, it is possible to prevent the incident light from passing through the side surface of the color filter 3 and to prevent the occurrence of color unevenness or the like at the screen edge. Incidentally, in FIG. 21, C _M is the center of the microlens 2, the C _F center of the color filter 3, the C _P represents the center of the light receiving portion 1.

[0007]

As described above, as one of the specific methods for micro-scaling the microlens array around the center of the imaging area, Japanese Patent Laid-Open Publication No.
Japanese Patent Application Laid-Open No. 140609/140 discloses that a photomask in which the entire mask pattern of the microlens array 2 is uniformly reduced at a predetermined magnification (<1) is used to reduce the pitch P ′ of the microlens array 2 to the pitch P of the light receiving unit 1. The method of making smaller is shown. In this method, the pitch P ′ of the microlens array is constant (P ′ = a × P (a <
1)).

The production of the photomask can be realized by applying a minute scaling to the mask pattern when drawing the mask pattern on a transparent substrate such as glass using an electron beam exposure apparatus. However, when fine scaling is performed only in the horizontal direction or only in the vertical (y-axis) direction, or when the reduction ratio in the horizontal direction is different from that in the vertical direction, it is necessary to modify the hardware of the electron beam exposure apparatus. Further, it becomes difficult to mix the apparatus with the case of manufacturing a photomask for an ordinary LSI, and the productivity is reduced.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a solid-state imaging device capable of correcting shading without applying micro scaling to a microlens array, and a method of manufacturing the same.

[0010]

According to a first aspect of the present invention, there is provided a solid-state imaging device according to the first aspect, wherein a light-receiving portion and a light-collecting portion constituting a pixel have a first pitch and a first pitch, respectively.
In the solid-state imaging device arranged in the imaging area at the same second pitch as the specific pitch, the specific light condensing unit in which the second pitch is changed by a predetermined dimension or the specific light receiving unit in which the first pitch is changed by a predetermined size Any one of which is disposed as the light-collecting unit or the light-receiving unit for a predetermined number of pixels from a central portion to a peripheral portion of the imaging region,
It is characterized in that the light condensing part is largely shifted stepwise from the light receiving part toward the periphery of the imaging region.

In this solid-state imaging device, due to the presence of the specific light-collecting portion or the specific light-receiving portion, the light-collecting portion is gradually reduced with respect to the light-receiving portion as it goes to the periphery of the imaging region without being subjected to reduction scaling. It is greatly shifted. Therefore,
“Vignetting” of incident light in the periphery of the imaging region is reduced, and shading is prevented.

In the solid-state imaging device according to the second aspect, the central portion and the peripheral portion of the imaging region are the central portion and the peripheral portion in the horizontal direction.

In this case, since the direction in which the light-collecting unit is shifted with respect to the light-receiving unit is in the horizontal direction of the imaging area, that is, in the x-axis direction, shading in the horizontal direction is prevented. In this specification, the horizontal direction is the x-axis direction, and the vertical direction is y
Refers to the axial direction.

[0014] In the solid-state imaging device according to the third aspect, the central portion and the peripheral portion of the imaging region are the central portion and the peripheral portion in the vertical direction.

In this case, the direction in which the light-collecting portion is shifted with respect to the light-receiving portion is the vertical direction, so that shading in the vertical direction is prevented.

In the solid-state imaging device according to the fourth aspect, the predetermined size change of the second pitch and the first pitch is performed by:
This corresponds to a predetermined size reduction of the pitch.

In the solid-state imaging device according to the fifth aspect, the change in the predetermined dimensions of the second pitch and the first pitch corresponds to an increase in the predetermined dimension of the pitch.

When the second pitch, that is, the pitch of the specific light-collecting portion is reduced, and when the first pitch, that is, the pitch of the specific light-receiving portion is increased, the direction of the shift of the light-collecting portion with respect to the light receiving portion is changed. , The shading is prevented when the exit pupil position is in front of the solid-state imaging device.

Conversely, when the second pitch, that is, the pitch of the specific light-collecting portion is enlarged, and when the first pitch, that is, the pitch of the specific light-receiving portion, is reduced, the light-collecting portion with respect to the light-receiving portion is reduced. Since the shift direction is the peripheral direction of the imaging region, shading is prevented when the exit pupil position is on the rear surface of the solid-state imaging device.

The change of the dimension of the second pitch can be achieved by changing the width of the condensing portion. It can also be achieved by changing the distance between adjacent light condensing parts.

In the solid-state imaging device according to the present invention, preferably, the pixels are arranged between the light-receiving portion and the light-collecting portion at the same third pitch as the first and second pitches. While further having a layer, a specific intermediate layer obtained by changing the third pitch by a predetermined dimension is arranged as a certain number of the intermediate layers from a central part of the imaging region to a peripheral part for a predetermined number of pixels, The closer to the periphery of the imaging area, the larger the intermediate layer is shifted from the light receiving section in the same direction as the light collecting section.

According to a ninth aspect of the present invention, the intermediate layer includes a color filter layer. In this solid-state imaging device, the color filter layer is also displaced from the light receiving portion in the same direction as the light condensing portion. Light components are prevented from entering from the side surface of the filter, and color unevenness at the screen edge is prevented.

In the solid-state imaging device according to the tenth aspect, the specific light-collecting portion and the specific intermediate layer are arranged at the same position.

Further, a method for manufacturing a solid-state imaging device according to the present invention is a method for manufacturing a solid-state imaging device according to any one of the first to tenth aspects. A manufacturing method according to claim 11 is characterized in that the imaging region is divided into small regions having an equal number of pixels, and a fixed number of the specific light-collecting portions are arranged in each of the small regions. On the other hand, a manufacturing method according to a twelfth aspect is characterized in that the imaging region is divided into small regions having an equal number of pixels, and a fixed number of the specific light receiving units are provided in each of the small regions.

According to a thirteenth aspect of the present invention, the specific light-collecting portion or the specific light-receiving portion is arranged at a random position in each of the small regions.
The random position can be determined based on a random number.

In the method of manufacturing the solid-state imaging device, the specific light-collecting portion or the specific light-receiving portion can be arranged without extreme bias over the entire imaging region. Therefore, the light-collecting portion is not uneven with respect to the light-receiving portion and largely shifted toward the periphery of the imaging region, so that shading is prevented without causing image defects such as sensitivity unevenness and fixed patterns.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in FIGS. 1 to 14, the same components as those of the conventional solid-state imaging device shown in FIGS. 15 to 21 are denoted by the same reference numerals, and detailed description is omitted.

FIGS. 1A and 1B are schematic views showing a solid-state imaging device according to a first embodiment of the present invention. FIG. 1A is a plan view showing a pixel array, and FIG. 1B is a cross-sectional view taken along line AA ′ in FIG. FIG.
The left side in the figure is the center of the imaging region in the horizontal (x-axis) direction of the chip, and the right side is the periphery (right end) of the imaging region in the horizontal direction of the chip. In the figure, 1 is a light receiving section, 2 is a micro lens, and 2a is a micro lens whose width is reduced by a predetermined dimension w 'in the horizontal direction from the micro lens 2. The reduced dimension w ′ is not more than 0.5% with respect to the width w of the microlens 2. The micro lens 2, 2a
Are provided in a one-to-one correspondence with the light receiving units 1, and one corresponding microlens and one light receiving unit constitute one pixel. At the center of the imaging region, the center of the light receiving unit and the center of the microlens coincide. Also, the micro lens 2a
Are arranged for every predetermined number of pixels from the center of the imaging region to the peripheral portion, that is, one for every predetermined number of pixels. As a result, the microlenses are gradually shifted from the light receiving unit toward the center of the imaging region toward the periphery of the imaging region.

FIG. 2 is a detailed view of an imaging area per one horizontal line in the solid-state imaging device shown in FIG. As typically shown in this figure, one horizontal line includes a predetermined number of lines from the center of the imaging region to the left end of the imaging region.
nl reduction microlenses 2a, and a predetermined number nr of reduction microlenses 2 from the center of the imaging area to the right end of the imaging area.
“a” is provided for every predetermined number of pixels from the center of the imaging area to the periphery. At this time, the adjacent distance s between the micro lenses 2, 2a is constant. Further, at the center of the imaging region, the center of the light receiving unit 1 and the center of the microlens 2 coincide.

Since the width of the microlens 2a is smaller than the width w of the microlens 2 by w ', the pitch of the microlens (the pitch referred to here) in the first microlens 2a from the center of the imaging area toward the right end portion. Is based on one end of the microlens in the horizontal direction), and is reduced by w ′, and the center of the microlens 2a is shifted from the center of the corresponding light receiving unit 1 by w ′ / 2 toward the center of the imaging region. (Note that when the pitch of the microlenses is viewed as the distance between the centers of the microlenses, the microlenses 2a
And the pitch between the microlens 2 on the left and right sides are w '
/ 2. Also, the center of the microlens 2 disposed between the first microlens 2a and the second microlens 2a is shifted from the center of the corresponding light receiving section 1 by w 'toward the center of the imaging area. . Further, in the second micro lens 2a, the center of the micro lens 2a is further shifted by w '/ 2 in the direction of the center of the imaging area, so that the center of the micro lens 2a is (3/2) with respect to the corresponding light receiving unit 1. The position shifts toward the center of the imaging region by w ′. And the second micro lens 2
The center of the microlens 2 disposed between a and the third microlens 2a is shifted from the center of the corresponding light receiving section 1 by 2w 'toward the center of the imaging area. In this way,
The closer to the periphery of the imaging area, the center of the microlens is gradually shifted from the center of the light receiving unit by a predetermined number of pixels step by step, hl = nl × w ′ at the leftmost end and hr = nr × w ′ at the rightmost end. Will shift. By arranging the microlenses 2 and 2a for all the horizontal lines in the same manner as described above, the reduced microlenses 2a are arranged over the entire imaging area, and for all the horizontal lines, the microlens array is located at the leftmost end of the imaging area. And the shift amount hl, hr at the right end
Only in the direction of the center of the imaging region with respect to the light receiving unit.

FIG. 5 is a cross-sectional view schematically showing how incident light is collected in the solid-state imaging device according to the first embodiment. “Vignetting” of the incident light in the periphery of the imaging region is reduced, and the shading is corrected as shown by the solid line in FIG. The pixel formed by the reduced microlens 2a may be less sensitive than the pixel formed by the microlens 2 having a normal size. Since it is as small as 0.5% or less, image defects such as sensitivity unevenness and fixed patterns are not recognized by the eyes. Further, in order to correct the shading symmetrically, it is apparent that the above nr and nl are preferably equal or very close. The dimension w ′ can be set to, for example, the minimum grid dimension of electron beam exposure data at the time of manufacturing a photomask. It is desirable that the minimum grid be as small as possible, but it is set to an optimum value in consideration of the throughput and mass productivity of the electron beam exposure apparatus.

Next, a method of forming the microlens in the first embodiment will be described with reference to FIG.

FIG. 6 is a diagram in which the entire imaging region having the number of horizontal pixels Nx and the number of vertical pixels Ny is equally divided into small regions R having the number of pixels (Bx × 1). hl and hr are horizontal displacement amounts of the center of the micro lens 2 from the center of the light receiving unit 1 at the leftmost end and the rightmost end of the imaging region, respectively, and Cx is the number of small regions R in the horizontal direction. In each small region R, only one microlens 2a having a reduced width in the horizontal direction is arranged at a random position. This random position is determined based on a random number in the range of 1 to Bx. That is, when the random number is 1, the micro pixel is located at the leftmost end of the small region R, when the random number is 2, the second pixel from the left end of the small region R, and when the random number is N, the micro pixel is located at the Nth pixel from the left end of the small region R. The lens 2a is provided.

In such a configuration, the desired shift amount hl
And hr, Cx = (hl + hr) / w 'Cx and Bx are obtained from the relationship of Bx = Nx / Cx = Nx / ((hl + hr) / w'). However, as described above, w 'is set to the minimum grid size of the electron beam exposure data, so hl and hr are multiples of w'. The above equation is B
In the case where x is completely divided, and when the division is not possible, as shown in FIG. 7, the first small region R1 of the number of pixels (Bx × 1) and the first small region R1 of the number of pixels ((Bx + 1) × 1) are used. Second small region R
2 are evenly arranged in the imaging area. The numbers of the first and second small regions R1 and R2 in the horizontal direction are respectively represented by Cx
Assuming that 1, Cx2, each variable is determined by the relationship of Bx = integer part of (Nx / Cx) Cx2 = decimal part of (Nx / Cx) × Bx Cx1 = Cx-Cx2.

With such a configuration, the microlenses whose pitch has been reduced are arranged at approximately the same number of random positions to the left and right with respect to the center of the imaging region without extreme deviation of the position over the entire imaging region. Also, a certain vertical (y
When looking at the line in the (axis) direction, the difference between the shift amounts of the vertically adjacent microlenses with respect to the light receiving unit does not become larger than w ′. That is, the microlens is largely and uniformly shifted stepwise in the direction toward the center of the imaging region toward the periphery of the imaging region with respect to the light receiving unit, and as described above, the pitch reduction dimension w ′ is smaller than the width w of the microlens. Therefore, shading is corrected symmetrically without any image defects such as sensitivity unevenness and fixed patterns. Therefore, FIG.
As shown by the solid line in FIG. 8, shading can be corrected without any difference from the conventional structure. FIG.
8, if the shading Sh is defined as Sh (%) = (Ve / Vo) × 100, for example, the diagonal length of the imaging region is 4.5 mm (1
/ 4 inch optical system) with an exit pupil distance of 1
In the case of 2.5 mm, the shading with respect to the shift amount (hl and hr) between the center of the light receiving unit and the center of the micro lens at the edge of the imaging region is as follows: hl = hr = 0 Sh = 65% hl = hr = 0.3 um, Sh = 90%. Needless to say, a value of Sh closer to 100% results in a smaller degree of shading, that is, a smaller decrease in luminance at the periphery of the screen. The values of hl and hr are
It varies depending on various parameters such as the exit pupil distance, the diagonal length of the imaging region, and the structural parameters of the pixels.

Although the microlenses 2a are randomly arranged in the above-described microlens configuration method, the positions of the microlenses 2a may be sequentially shifted between horizontally adjacent horizontal lines even if they are not random. In addition, the micro lens 2a can be disposed evenly in the imaging area.

Next, FIG. 3 shows a second embodiment of the present invention. In the first embodiment, the microlens is shifted with respect to the light receiving unit 1 by reducing the width of the microlens by w ′ for each predetermined number of pixels. However, in the second embodiment, the microlens is shifted. Instead of reducing the width of the lens, the distance s between the microlenses is reduced by w ′. In this point, the present embodiment is different from the first embodiment, but has the same effect as the first embodiment. Obtainable.

In FIG. 3, reference numeral 2b denotes a microlens whose distance from the left adjacent microlens 2 is reduced by w 'from a predetermined dimension s. Of course, the micro lens 2 and the micro lens 2b have the same width w. Similar to the microlens 2a in the first embodiment, the microlens 2b in this embodiment is also provided over the entire imaging area, and for every horizontal line, every predetermined number of pixels, that is, with respect to the predetermined number of pixels. Provided in one ratio. At the center of the imaging region, the center of the light receiving unit 1 and the center of the microlens 2 match.

In this embodiment, the distance between the first microlens 2b and the microlens adjacent to the left is reduced by w 'from the center of the imaging area toward the right end. The center of the lens 2b is shifted from the center of the corresponding light receiving unit by w 'toward the center of the imaging area. Also, the center of the microlens 2 disposed between the first microlens 2b and the second microlens 2b is shifted from the center of the corresponding light receiving section 1 by w 'toward the center of the imaging area. Further, in the second microlens 2b, the distance from the left microlens is w ′.
, The center of the microlens 2b is shifted from the corresponding light receiving section 1 by 2w 'toward the center of the imaging area. In this manner, the light-receiving unit and the microlens gradually shift by a predetermined number of pixels step by step toward the periphery of the imaging region, and hl = nl × w at the leftmost end as in the first embodiment. ', At the rightmost end, hr = nr × w'.

Next, FIG. 4 shows a third embodiment of the present invention. In the same figure, 2a is a microlens whose width is reduced by a dimension w ′ in the horizontal direction as in the first embodiment, and 2c is a microlens whose width is reduced by a dimension w ′ in the horizontal direction,
In addition, this is a microlens in which the distance s from the left adjacent microlens is enlarged by the dimension w ′. A predetermined number nl from the center of the imaging area to the left end of the imaging area per one line in the horizontal direction
A predetermined number from the center of the imaging area to the right end of the imaging area
The nr microlenses 2a are provided for every predetermined number of pixels, and between these microlenses 2a, a predetermined number of microlenses 2c and microlenses 2 are sequentially arranged. At the center of the imaging region, the center of the light receiving unit 1 and the center of the microlens 2 match. The first micro lens 2a from the center of the imaging area to the right end
In (2), the pitch of the microlenses (the pitch based on one horizontal end of the microlens) is reduced by w ′, and the center of the microlens 2a is shifted by w ′ / 2 from the center of the corresponding light receiving unit toward the center of the imaging region. Deviate. In addition, the center of the microlens 2c disposed between the first microlens 2a and the second microlens 2a is shifted from the center of the light receiving unit 1 by w ′ / 2 toward the center of the imaging area. The center of the adjacent microlens 2 is shifted from the center of the light receiving unit 1 by w ′ toward the center of the imaging area. (Note that when the pitch of the microlenses is viewed as the distance between the centers of the microlenses, the pitch between the microlenses 2a and the microlens 2 on the left is reduced by w ′ / 2. Pitch w 'with micro lens 2
/ 2). Further, in the second microlens 2a, the pitch of the microlenses is reduced by w ', and the center of the microlens 2a is shifted from the center of the corresponding light receiving unit 1 in the direction of the center of the 3 / 2w' imaging area. In this way, the light receiving unit and the microlens gradually shift by a predetermined number of pixels gradually toward the periphery of the imaging region, and hl = nl × w ′ at the leftmost end and hr =
nr × w '. By arranging the entire horizontal line in the same manner as described above, the reduced microlens 2a is arranged over the entire imaging area, and the entire horizontal line is set at the leftmost end and the rightmost end of the imaging area, respectively.
It is shifted by hl and hr with respect to the light receiving unit toward the center of the imaging area.
Microlens 2a having reduced width as in the present embodiment
And the microlens 2c having a reduced width and an increased distance between adjacent microlenses,
The same effect as that of the embodiment can be obtained.

Although the three representative embodiments have been described above, a microlens whose pitch has been changed by a predetermined dimension is arranged from the center of the imaging area to the peripheral area for each of a predetermined number of pixels. There may be various other methods of shifting the position of the light-receiving unit from the light-receiving unit in a stepwise manner toward the periphery of the imaging region.

In the embodiment described above, the pitch of the microlenses is reduced by setting the pitch of the light receiving section 1 to a constant P. However, as shown in FIGS. The same effect can be obtained by increasing the pitch of the light receiving section. In the figure, reference numeral 1a denotes a light receiving unit whose pitch is enlarged by w '. The point is that the pitch of some of the microlenses should be relatively small with respect to the light receiving unit.

In each of the above embodiments, the reduction of the horizontal pitch of the microlenses in the solid-state imaging device has been described. However, the vertical pitch is reduced as shown in FIG.
(2d in the figure is a microlens with reduced vertical pitch), or both horizontal and vertical pitches are reduced as shown in FIG. 11 (2e in the figure is a microlens with both horizontal and vertical pitch reduced) By doing so, shading in the vertical direction or both in the horizontal and vertical directions can be corrected. FIG. 10 and FIG. 12 show a method of forming each of these microlenses.

In FIG. 10, the entire image pickup area is represented by the number of pixels.
Evenly divide into (1 × By) small regions R3,
Inside, a microlens 2d having a reduced vertical pitch is arranged at a random position in a small area of one pixel. Also,
In FIG. 12, the entire imaging region is equally divided into small regions R4 having the number of pixels (Bx × By), and one microlens 2a having a reduced horizontal pitch is randomly assigned to each horizontal line in each small region R4. In each of the small areas R
For each line in the vertical direction in 4, one microlens 2d having a reduced vertical pitch is arranged at a random position. Here, the microlens 2e in the figure is a case where the positions of the microlenses whose horizontal and vertical pitches are reduced overlap each other, and is a microlens whose horizontal and vertical pitches are simultaneously reduced. With such a configuration, in the vertical direction of the solid-state imaging device, or in both the horizontal and vertical directions, the microlens is shifted stepwise with respect to the light receiving unit, so that the microlens is largely shifted toward the center of the imaging region toward the periphery of the imaging region. In addition, it is shifted evenly as a whole. As a result, there is no image defect such as sensitivity unevenness or fixed pattern, and the bidirectional shading in the horizontal and vertical directions is corrected symmetrically in the left-right and up-down directions.

In each of the above embodiments, a microlens whose pitch is reduced by a predetermined dimension is provided for every predetermined number of pixels from the center of the imaging area to the periphery.
The case where the microlens is shifted stepwise largely toward the center of the imaging unit toward the periphery of the imaging region with respect to the light receiving unit, that is, the exit pupil position is on the front surface of the solid-state imaging device has been described. 13, the microlenses 2f whose pitch is enlarged by a predetermined dimension are arranged for every predetermined number of pixels from the center to the periphery of the imaging region as shown in FIG. In some cases, the microlenses are gradually shifted from the light receiving unit toward the image pickup unit toward the periphery of the region.

In a color solid-state imaging device,
As shown in FIG. 14A, a color filter 3 is formed as an intermediate layer between the light receiving section and the microlens.
In this case, if only the microlens 2 is corrected as described above, the shift amount hr between the color filter 3 and the microlens 2a becomes larger near the imaging area. As a result, an incident light L component from the side surface of the color filter 3 is generated, and problems such as color unevenness at a screen edge occur. As a method for preventing this, as shown in FIG. 14B, similarly to the case of the micro lens, a color filter 3a whose pitch is reduced by a predetermined dimension is provided for every predetermined number of pixels from the center of the imaging area to the peripheral area. By disposing the color filters, the color filters are shifted stepwise from the center of the imaging region to the periphery of the imaging region with respect to the light receiving unit, and the color filters are shifted more greatly toward the periphery of the imaging region. In this case, the position of the micro lens 2a whose pitch is reduced by a predetermined dimension and the position of the color filter 3a are made the same. FIG. 14B is a cross-sectional view of a pixel portion around an imaging area according to this method. This prevents incident light components from the side surface of the color filter 3a, and eliminates problems such as color unevenness at the screen edge.

As described above, various embodiments of the present invention have been described. In addition to these embodiments, various configurations based on the gist of the present invention are possible.

[0048]

As described above, according to the present invention, a specific light-collecting portion or a specific light-receiving portion whose pitch has been changed by a predetermined size is provided for every predetermined number of pixels from the center to the peripheral portion of the imaging area. Accordingly, since the light-collecting portion is gradually shifted from the light-receiving portion toward the periphery of the imaging region, shading can be prevented without applying a minute scaling to the light-collecting portion, that is, the microlens array. In addition, by disposing an intermediate layer having a changed pitch by a predetermined dimension from the center of the imaging region to the peripheral portion for every predetermined number of pixels, the intermediate layer is also provided to the light receiving unit in the same manner as the light collecting unit. Therefore, it is possible to prevent the occurrence of problems such as color unevenness. Further, according to the present invention, since micro-scaling is not applied, a photomask for the light-collecting portion and the intermediate layer is used.
It can be manufactured in the same process as that for manufacturing a photomask for an ordinary LSI, and does not impair productivity.

[Brief description of the drawings]

FIG. 1A is a plan view of an imaging region of a solid-state imaging device according to a first embodiment of the present invention, and FIG. 1B is a cross-sectional view taken along line AA ′ of FIG.

FIG. 2 is a detailed plan view of an imaging region along the line AA ′ in FIG. 1;

FIG. 3 is a detailed plan view of an imaging region according to a second embodiment of the present invention.

FIG. 4 is a detailed plan view of an imaging region according to a third embodiment of the present invention.

FIG. 5 is an explanatory diagram illustrating a state of condensing incident light in an imaging region according to the first embodiment.

FIG. 6 is a diagram illustrating a microlens configuration method according to the first embodiment.

FIG. 7 is a diagram showing a microlens configuration method according to the first embodiment.

FIG. 8A is a plan view showing an imaging area according to another embodiment of the present invention, and FIG. 8B is a cross-sectional view taken along line AA ′ of FIG.

FIG. 9 is a plan view showing an imaging region according to another embodiment of the present invention.

FIG. 10 is a diagram showing a configuration method of a microlens in the embodiment of FIG. 9;

FIG. 11 is a plan view showing an imaging region according to another embodiment of the present invention.

FIG. 12 is a view showing a configuration method of a microlens in the embodiment of FIG. 11;

FIG. 13 is a view showing another embodiment of the present invention.

FIG. 14 is a detailed cross-sectional view of a pixel portion when the present invention is applied to a color solid-state imaging device.

FIG. 15 is a detailed sectional view of a pixel portion of a conventional solid-state imaging device.

FIG. 16 is an explanatory diagram showing a state of condensing incident light when the exit pupil distance is long in the solid-state imaging device in FIG. 15;

FIG. 17 is an explanatory diagram showing how the incident light is collected when the exit pupil distance is short in the solid-state imaging device in FIG. 15;

FIG. 18 is an output signal waveform diagram of a conventional solid-state imaging device.

FIG. 19 is a cross-sectional view of a conventional solid-state imaging device when the exit pupil distance is short.

FIG. 20 is a cross-sectional view of a conventional solid-state imaging device when an exit pupil position is on a rear surface.

FIG. 21 is a detailed sectional view of a pixel portion of a conventional solid-state imaging device.

[Explanation of symbols]

1, 1a: light receiving section, 2, 2a, 2b, 2c, 2d, 2
e, 2f: micro lens, 3, 3a: color filter, 4: light shielding film, 8: opening, R, R1, R2, R
3, R4 ... small area.

Claims (14)

[Claims] 1. A solid-state imaging device in which a light receiving section and a light collecting section constituting a pixel are arranged in an imaging area at a first pitch and a second pitch identical to the first pitch, respectively. Either the specific light-collecting portion whose pitch has been changed by a predetermined dimension or the specific light receiving portion whose first pitch has been changed by a predetermined size is provided for every predetermined number of pixels from the center to the periphery of the imaging region. The light collecting unit or the light receiving unit is arranged by a certain number, and the light collecting unit is gradually shifted from the light receiving unit toward the periphery of the imaging region. Solid-state imaging device. 2. The solid-state imaging device according to claim 1, wherein a central portion and a peripheral portion of the imaging region are a central portion and a peripheral portion in a horizontal direction. 3. The solid-state imaging device according to claim 1, wherein a central portion and a peripheral portion of the imaging region are a central portion and a peripheral portion in a vertical direction. 4. The solid according to claim 1, wherein the predetermined size change of the second pitch and the first pitch corresponds to a predetermined size reduction of the pitch. Imaging device. 5. The solid according to claim 1, wherein the predetermined size change of the second pitch and the first pitch corresponds to a predetermined size increase of the pitch. Imaging device. 6. The solid-state imaging device according to claim 1, wherein the width of the specific light-collecting portion is different from the width of the light-collecting portion by the predetermined dimension. 7. The space according to claim 1, wherein an interval between the specific light-collecting portion and the adjacent light-collecting portion is different from an interval between the light-collecting portions by the predetermined dimension. Solid-state imaging device. 8. The pixel further includes an intermediate layer between the light receiving unit and the light condensing unit, the intermediate layer being arranged at the same third pitch as the first and second pitches.
The specific intermediate layer whose pitch has been changed by a predetermined dimension is arranged as a certain number of the intermediate layers from the center of the imaging region to the peripheral portion for every predetermined number of pixels. 8. The method according to claim 1, wherein the intermediate layer is largely shifted stepwise with respect to the light receiving section.
The solid-state imaging device according to any one of the above. 9. The solid-state imaging device according to claim 8, wherein said intermediate layer includes a color filter layer. 10. The solid-state imaging device according to claim 8, wherein the specific light-collecting portion and the specific intermediate layer are arranged at the same position. 11. The method of manufacturing a solid-state imaging device according to claim 1, wherein the imaging area is divided into small areas having an equal number of pixels, and A method for manufacturing a solid-state imaging device, comprising: arranging a fixed number of the specific light collecting units. 12. The method of manufacturing a solid-state imaging device according to claim 1, wherein the imaging area is divided into small areas having an equal number of pixels, and A method for manufacturing a solid-state imaging device, wherein a certain number of the specific light receiving units are provided. 13. The method for manufacturing a solid-state imaging device according to claim 11, wherein the specific light-collecting unit or the specific light-receiving unit is arranged at random positions in each of the small regions. 14. The method according to claim 13, wherein the random position is determined based on a random number.