JPH06209095A - Solid image sensor - Google Patents

Abstract

PURPOSE: To provide a solid image sensor with an integral optical system and a method for manufacturing the solid-stage image sensor. CONSTITUTION: A solid-stage image sensor has a substrate 104, an array 102 of a photosensitive member being arranged on the surface of the substrate 104, and a light transmission layer 106 that is located at the upper part of the array is adjacent to it and at the same time causes light to be converged onto the array.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state image sensor, and more particularly to a solid-state image sensor for forming an image on a photosensitive semiconductor device.

[0002]

2. Description of the Related Art Recent charge-coupled devices and other photosensitive semiconductor devices (hereinafter "solid-state image sensors")
Can output a signal representative of the (focused) image formed on its surface. Generally, the surface of a solid-state image sensor has photosensitive semiconductor elements (eg, gates or junctions) that are isolated from each other.
Arrays (e.g., columns and rows) of which the location of a particular array corresponds to a particular "pixel" (or location) in the image. For example, modern video cameras use lens systems (optics) that are separate from each other to focus and form images on such solid-state image sensors.

Generally, a single "shooting" lens is
An image can be focused on the array by supporting it at a fixed spacing of at least a few millimeters or 10 millimeters from the array of photosensitive members.
This array is located in the focal plane of the lens. In front of the taking lens, an additional lens focuses and magnifies the image.

Binary (diffractive)
For optical components, "Binary Optics", S
scientific American, May 1992.
Mon, p. 92, 94-97 ("Article").

US Pat. No. 4,425,501 discloses a transparent member 20 having a plurality of lens bodies formed thereon. The transparent member is “attached” above the die 10. Each lens body is associated with a pair of detectors on the die.

US Pat. No. 4,553,036, in FIG. 3A thereof, discloses two one-dimensional arrays 21 with photosensitive detectors juxtaposed with a cylindrical lens 21. Furthermore, as shown in FIG. 14, three rows of one-dimensional sensors are provided and red (R), green (G) and blue (B) filters can be attached, and thus signals from the respective sensors can be attached. Is read independently to obtain color information.

US Pat. No. 4,636,631 discloses a lens 8 assembled on a wafer 2 on a substrate 1 having shims 6, 7 for measuring thickness and a layer of photoresist 5.

US Pat. No. 4,733,096 discloses in FIG. 2 a lens structure (“sensor substrate” 3).
2; 32a, 32b, 38). Insulation layer 4
2 in parallel with the lens structure 32. The sensor 44 is arranged in parallel with the insulating layer 42.

In addition to this, as a known example, US Pat.
51,862 and 4,899,174.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide an improved solid-state image sensor.

A further object of the present invention is to provide a method for manufacturing the above solid-state image sensor.

A further object of the present invention is to provide a solid-state image sensor having an integrated optical system.

Another object of the present invention is to provide a solid-state image sensor useful for color images.

A further object of the present invention is to provide an imaging method using the above solid-state image sensor.

Another object of the present invention is to provide an imaging device. In the preferred embodiment, the imaging device comprises a camera. Desirably, the camera includes the solid-state image sensor described above.

[0016]

SUMMARY OF THE INVENTION The present invention is directed to a substrate, an array of photosensitive members disposed on the surface of the substrate, and light on and above and adjacent to the array. And a light transmission layer capable of converging.

According to an embodiment of the present invention, a light transmission layer is integrally formed on a substrate having an array of photosensitive members on its surface. The light transmission layer comprises an array of lens bodies, preferably binary optics. There is a one-to-one correspondence between the lens bodies and the photosensitive members. By disposing these lens bodies physically or apparently offset from the photosensitive member, each photosensitive member constitutes the only pixel of information corresponding to one position in the incident image. Overall, the photosensitive member provides a complete two-dimensional representation of the incident image.

Furthermore, according to the present invention, the photosensitive member can be arranged regularly, irregularly, in a square shape, or in a rectangular shape.

Further in accordance with the present invention, the array of photosensitive members can cover substantially the entire underlying substrate, or only selected areas (eg, central areas) of the substrate.

Further in accordance with the present invention, an opaque masking layer can be provided between the lens body layer and the photosensitive member, with the masking layer provided with holes aligned with the photosensitive member. be able to. With such a structure, it is possible to prevent the light converged by the lens body without entering the photosensitive member from impacting the circuit elements arranged on the substrate between the photosensitive members.

Further, according to the present invention, an optical transmission layer can be provided between the layer containing the lens bodies and the photosensitive member. This light transmission layer acts as an integral isolation layer between the substrate and the layer containing the lens bodies.

Further according to the invention, both the light transmission layer and the masking layer can be arranged between the layer containing the lens bodies and the surface of the substrate. The light transmission layer can be disposed on the masking layer and vice versa.

Further in accordance with the present invention, various materials and techniques are described for the layer containing lens bodies, the masking layer, and the (in between) light transmission layer.

Further in accordance with the invention, the lens body is formed as a preferably (rather than refractive) diffractive optical device.

According to another embodiment of the present invention, the light collecting member is supported on the surface of the substrate by the package body or the like.

Further, according to the present invention, the first optical member is supported on the surface of the substrate by the package body or the like,
The optical member of 1 is integrally formed on the substrate. By incorporating these two optical members, at least one of spherical aberration and chromatic aberration can be minimized by one of the optical members.

Further in accordance with the invention, the photosensitive members are aligned as "triplets" (or "triple pairs") slightly spaced apart from each other and the triplets are aligned in an array. The upper light transmission layer has a lens body formed therein. One lens body is associated with each triplet of photosensitive members. The lens body is preferably a diffractive device, which diffracts different wavelengths of light incident on a particular one of the three photosensitive members in the triplet (e.g.,
Red, green, blue) can be converged.

Further in accordance with the present invention, three monochromatic image sensors are arranged in a linear array, a curved array, or a triangular pattern. The additional optical member acts as a beam splitter, and can separate different wavelengths of light incident on a specific one of the three monochromatic image sensors.

Other objects, features and effects of the present invention will be clarified in the following description.

[0030]

In the solid-state image sensor according to the present invention, various configurations using the optical member related to the photosensitive member are described. In one configuration, the optical member is formed integrally with a substrate including a photosensitive member. In another configuration, the optical member is attached to a package or the like including the substrate and the optical member. Yet another configuration employs two or more optical members including a conventional refractive member, a refractive converging member, and a refractive beam splitting member. It describes its use as a fixed image sensor. It describes its use for monochrome and color images. A method of manufacturing these is described.

[0031]

1 illustrates a basic solid state image sensor 100 according to the present invention. A photosensitive member 102 (denoted by a dot “·”) is formed on the front surface (top surface in the drawing) of the substrate 104. The photosensitive member 102 may be a memory cell that discharges with incident light, or may be any other suitable device that changes state or produces a potential or potential difference with incident light. Board 1
04 can be a silicon semiconductor die.
Other suitable semiconductor materials can also be used. The photosensitive members 102 are arranged in an array, or in a matrix of hundreds to thousands (only 6 columns and 6 rows are shown for simplicity). Preferably, the photosensitive member 1
02 is a square (m rows × m) formed by elements arranged at equal intervals.
Align this in an array of columns) or a rectangle (m rows x n columns). However, the photosensitive members 102 in one column (or row) can be arranged offset from the elements in adjacent columns (or rows). In FIG. 2, the photosensitive members 102 are arranged in a matrix of squares arranged in a matrix. In FIG. 3, the photosensitive member 102 'is
It is arranged in a rectangle on the surface of the substrate 104 'and has a row (or row) of photosensitive members 10 arranged therein.
2'is an adjacent column (or row) of photosensitive member 102 '
I have shifted this.

Returning to FIG. 1, the optical transmission layer 106 is provided on the substrate 10.
4, covering at least the entire array of photosensitive members 102 (or 102 ', 102 ", described below). In Figure 1, the photosensitive members 102 cover substantially the entire surface of substrate 104. However, it is within the scope of the invention that the array of photosensitive members 102 occupy only selected areas, for example, as shown in FIG. This is the central region 103 (enclosed by the dotted line) of the substrate 104 ″ covered by the photosensitive member 102 ″.

In FIG. 2, one column of photosensitive members 102 is aligned with an adjacent column of photosensitive members 102, and one row of photosensitive members 102 is aligned with an adjacent row of photosensitive members 102. is doing.

In FIG. 3, one row of photosensitive members 102 'is offset (perpendicular to) the adjacent row of photosensitive members 102' and one row of photosensitive members 102 '.
Are offset from the photosensitive members 102 'in adjacent rows.

Returning to FIG. 1, the light transmission layer 106 is made of a suitable light transmission material such as silicon dioxide (SiO ₂ ), spin-on glass, reflow glass, photoresist, spin-on photoresist, reflow photoresist, or the like. Formed and preferably have a substantially uniform thickness. A layer having a relatively uniform thickness is formed by a spin-on technique or a reflow technique. Optical transmission layer 10
If the thickness of 6 is not uniform at the initial formation, it is desirable to flatten it by a chemical mechanical polishing method or the like.
For the method of chemical mechanical polishing, see, for example, US Pat. Nos. 4,671,851, 4,910,155, and 4,944,836.

Alternatively, the light transmission layer 106 may be formed as a precipitation layer having a relatively uniform thickness. See, for example, "Precipitation Deposition of Photoresist on a Semiconductor Wafer," filed June 29, 1992, by Ross Talker, U.S. Patent Application No. 906,902.

The thickness of the light transmission layer 106 can be verified by an optical interference technique or the like, and finally it can be adjusted to an appropriate thickness.

As shown in FIG. 1, a plurality of lens members or “lens bodies” 108 are formed on the light transmission layer 106.
(Indicated as a circle marked with a circle). These lens bodies 108 are formed by the photosensitive members 102 located in the lower layer.
To one-to-one with respect to each other, they are arranged as an array or as a matrix of hundreds to thousands (only 6 columns and 6 rows are shown for simplicity). The lens bodies 108 (lens members) are aligned with the upper layer of the photosensitive member 102 by one of the various methods described below. Preferably, this lens body 108
Is preferably formed as a diffractive (binary) optical structure imageable on the underlying photosensitive member 102.

Generally, each lens body 108 is
Although it is located directly above its corresponding photosensitive member 102, each pair of lens bodies 108 and corresponding photosensitive member 102 has a specific portion of the image focused on the substrate 104. In particular, it should be aligned to sense. This structure is formed by one of various methods.

FIG. 5 shows three photosensitive members 102a, 10a.
Corresponding three lens bodies 10 in the upper layers of 2b and 102c
8 shows a configuration 200 of 8a, 108b, 108c. In this example, the photosensitive members 102a, 102b, 102c are arranged in a regular array at regular intervals "d" (in the figure, three photosensitive members 102a, 102a, 102).
b, 102c and lens bodies 108a, 108b, 1
08c only is shown). On the other hand, the lens body 108
a, 108b, 108c have their spacing varied to align them in an irregular array. Especially, the lens body 1
Reference numeral 08a is one-dimensionally or two-dimensionally displaced from the photosensitive member 102a and is arranged. Lens body 108b
Are arranged right above the photosensitive member 102b. The lens bodies 108c are arranged so as to be displaced in the opposite direction (from the shifting direction of the lens bodies 108a) from the photosensitive member 102c. In this way, the substrate 1
A specific portion (eg, top left, center, bottom right, etc.) of the image formed on 04 is a particular photosensitive member 102.
Is converged to. Each photosensitive member 102 is a substrate 1
The information related to a certain "pixel" of the image formed in 04 is output. As a whole, the plurality of photosensitive members 102 output the pixel information of the entire image, and each pixel represents a specific portion of the image. Various physical staggering structures for the lens bodies 108 provide these results. That is, it covers the entire two-dimensional surface of the image.

FIG. 6 shows three photosensitive members 102d and 10
Corresponding three lens bodies 10 in the upper layers of 2e and 102f
8d shows another configuration 210 of 8d, 108e, 108f. In this example, lens bodies 108d, 108e, 108f
Aligns it in a regular (equally-spaced) array with regular spacing "s". On the other hand, the photosensitive members 102d, 10
2e, 102f have this arranged in an irregular (spaced) array. In particular, the photosensitive member 102d
Are arranged one-dimensionally or two-dimensionally from the lens bodies 108d. The photosensitive member 102e is arranged immediately below the lens body 108e. The photosensitive member 102f is arranged so as to be displaced in a direction opposite to the lens small body 108f (the direction in which the photosensitive member 102d is displaced). In this way, a particular portion of the image formed on the substrate 104 (eg, top left, center, bottom right, etc.) is focused on a particular photosensitive member 102. Each photosensitive member 102 outputs information related to a certain "pixel" of the image formed on the substrate 104. Similar to the configuration of FIG. 5, as a whole, the plurality of photosensitive members 102 output the pixel information of the entire image, and each pixel represents a specific portion of the image. Various physical staggering structures for the photosensitive member 102 provide these results. That is, it covers the entire two-dimensional surface of the image.

FIG. 7 shows three photosensitive members 102g and 10g.
Corresponding three lens bodies 10 in the upper layer of 2h, 102i
8 shows another configuration 220 of 8g, 108h, 108i. In this example, lens bodies 108g, 108h, 108i
Aligns it in a regular (equally-spaced) array at regular intervals "s", while
02h and 102i are also arranged in a regular array with a regular spacing "d". In other words, the lens bodies 108g, 108h, and 108i are physically displaced so that the lower photosensitive members 102g, 102h, and 102 are not moved.
It is in a state of being physically aligned with i. If all the lens bodies 108g, 108h, and 108i are formed to be the same (the convergence parameters are the same), all the photosensitive members 102g, 102h, and 102i have the same pixel as the other photosensitive member 102. It means outputting information. Therefore, the lens bodies 108g, 10
8h and 108i are respectively formed as binary (diffractive) optical systems having uniform convergence characteristics. In particular, the lens body 108g is formed by shifting the focus of the lens body from the photosensitive member 102g one-dimensionally or two-dimensionally. The lens body 108h is formed so that its focus is on the photosensitive member 102h. The lens body 108i has its focus on the photosensitive member 1
02i is arranged in line with the lens small body 108i, and is arranged in the opposite direction (opposite to the shifting direction of the lens small body 108g). Thus, the lens body 108 and the photosensitive member 1 are in sharp contrast to the physical offset structure described in FIGS. 5 and 6.
02 to form a pair of "apparent" staggered structures. However, the result is similar in that certain parts of the image formed on the substrate 104 (eg, top left, center, bottom right, etc.) are focused onto a particular photosensitive member 102. is there. Each photosensitive member 102 outputs information related to a certain "pixel" of the image formed on the substrate 104. Similar to the configuration of FIGS. 5 and 6, as a whole, a plurality of photosensitive members 102 are provided.
Outputs pixel information of the entire image, and each pixel represents a specific portion of the image. Due to the various apparent staggering structures for the photosensitive member 102,
You get these results. That is, it covers the entire two-dimensional surface of the image.

The commonality of the configurations shown in FIGS. 5, 6 and 7 is that the relative directionality of the lens body 108 and the photosensitive member 102 (regardless of physical or appearance) is small. The light from the selected portion of the image formed on the substrate 104 by the body 108 is transferred to one photosensitive member 1
02, that is, the photosensitive members 102 of this array as a whole are aligned to output a complete pixel-by-pixel image (ie, a signal representative of the incident image).

On the other hand, in each of the configurations 220, 210 or 220 shown in FIG. 5, 6 or 7,
Light from a particular portion of the image formed on the die (substrate 104) is transmitted by all lens bodies 108 to the substrate 104.
Converged on. However, light from a particular portion of this image is focused on only one of the photosensitive members 102. For the rest of the photosensitive member 102, light from that particular portion of the image is focused on the surface of the substrate 104 in the areas between the photosensitive members 102. It is also within the scope of the present invention that there may be circuitry (eg, image processing circuitry) formed on the surface of substrate 104 in the areas between photosensitive members 102, or in any other suitable area. Conversely, such circuits can be affected by light. Thus, these areas between the photosensitive members 102 are preferably "masked" with an opaque layer such as silicon nitride, aluminum, or an opaque photoresist (ink).

FIG. 8 shows a configuration 300 similar to that of FIG. However, in this example, an optically opaque masking layer 310 is formed over the substrate 304 and surface circuitry (not shown) on the substrate 304. The masking layer 310 is formed of an appropriate material such as silicon nitride or opaque photoresist, and has openings 312 (holes) vertically aligned with the plurality of photosensitive members 302 on the surface of the substrate 304. To have.
Similar to that shown in FIG. 4, the array of photosensitive members 302 may cover only a portion of the surface of the substrate 304. A light transmitting layer 306 is formed on top of the opaque masking layer 310 and is formed to fill the holes 312 while maintaining a relatively flat surface. The light transmission layer 306 also has a lens body 3 on its exposed surface.
It may also be subjected to chemical mechanical polishing before forming 08. A lens body 308 (preferably diffractive) is formed in the light transmission layer 306. The techniques described in connection with FIGS. 2, 3, 5, 6 and 7 are also applicable to this configuration 300 using an additional masking layer 310.

In some applications, the substrate, the photosensitive member, the masking layer (if used), and the lens member are maintained as a unitary structure while the lens member (eg lens It is desirable to place the small bodies 108, 308) away from the photosensitive member (eg, photosensitive members 102, 302). Such a configuration allows greater freedom in the design of lens bodies, such as increasing the depth of focus.

FIG. 9 shows a configuration 400 similar to the structure of FIG. However, in this example, the optical transmission layer 410 is
It is formed as an upper layer of the substrate 404 and circuit elements (not shown) on the surface of the substrate 404. The light transmission layer 410 is formed on the substrate 404, preferably by forming the light transmission layer 410 to have a uniform thickness.
Compensates for geometrical non-uniformities that may be caused by the underlying photosensitive member (not shown) on the surface of the. The light transmission layer 410 is formed from a suitable light-transmittable material such as silicon dioxide (SiO ₂ ), spin-on glass, reflow glass, photoresist, spin-on photoresist, reflow photoresist, and preferably substantially. It shall have a uniform thickness. A layer having a relatively uniform thickness is formed by a spin-on technique or a reflow technique. If the thickness of the light transmission layer 410 is not uniform at the initial formation, it is desirable to flatten it by a chemical mechanical polishing method or the like. Alternatively, the light transmission layer 410 may be formed as a precipitation layer having a relatively uniform thickness as described above.

In FIG. 8, the opaque layer 310 functions as a masking layer, thereby allowing the photosensitive member 302 to be exposed.
While preventing light converging on the off-center from impacting the circuit elements between the photosensitive members 302, in this example shown in FIG. 9, the light transmission layer 410 is a “separator”.
Appropriate (increased) to the upper layer 406 including the lens bodies 408 by functioning as a (standoff).
I try to make a space.

As shown in FIG. 4, the array of photosensitive members in the above configuration 400 can cover only a portion on the surface of the substrate 404. Furthermore, as shown in FIGS.
The technique described with reference to FIGS. 5, 6 and 7 can be applied to the optical transmission layer 410 as the isolation member.

FIG. 10 illustrates a configuration 420 that combines the disclosure of FIGS. 8 and 9. In this example, masking layer 422 (similar to masking layer 310) is applied to substrate 404 '.
The masking layer 422 has holes (not shown) aligned with a photosensitive member (not shown). A light transmission isolation layer 424 (similar to light transmission layer 410) is formed over the masking layer 422. Optical transmission layer 40
6'is formed on the optical transmission isolation layer 424, and a lens body (not shown) is provided. 2, FIG. 3, FIG. 4, FIG. 5, FIG.
And the techniques described in connection with FIG. 7 are applicable to this configuration 420 as well.

FIG. 11 illustrates a configuration 440 that combines the disclosures of FIGS. 8 and 9. In this example, a light transmission isolation layer 444 (similar to light transmission layer 410) is formed over the substrate 404 ″. An opaque masking layer 442 (similar to masking layer 310) is formed over the light transmission isolation layer 444. The masking layer 442 has holes (not shown) aligned with a photosensitive member (not shown). An optical transmission layer 406 ″ is formed on the masking layer 442 to form a lens body ( (Not shown). The techniques described in connection with FIGS. 2, 3, 4, 5, 6, and 7 are also applicable to this configuration 440.

Lens member (for example, lens body 10)
8, 308, 408) and a photosensitive member (eg, photosensitive member 102, 302, 402) by providing an appropriate amount of spacing to provide a different or additional lens member configuration. Can be realized.

FIG. 12 shows configuration 500, which is configuration 5
In 00, a large lens member 508 is formed in the light transmission layer 506 which is an upper layer of the array of the photosensitive members 502 on the substrate 504. Preferably, this large lens member 508 forms it as a single binary (diffractive) optical device, covering the entire array of photosensitive members 502. 2, FIG. 3, FIG. 4, FIG. 8, FIG.
The techniques described in connection with FIGS. 10 and 11 are also applicable to this configuration 500. An optical transmission layer (not shown) is preferably provided between the single large lens element 508 and the surface of the substrate 504 (similar to the optical transmission layer 410 shown in FIG. 9).

FIG. 13 shows a configuration 600 having a lens member 608 that is not integral with the substrate as in the various embodiments and configurations described above. In this configuration 600, the lens member 608 is attached to a package 620 or the like that includes a substrate 602 (an array of photosensitive members (not shown)) rather than being a single piece. The package body sidewalls 622 form a known isolation member for the lens member 608 (ie, distance between the lens member 608 and an array of photosensitive members on the surface of the die). The lens member 608 is preferably a refractive optical member, similar to the previously described members (eg, lens bodies 108, 308, 408, and large lens member 508), but in this example it is not integral with substrate 602. Absent. Furthermore, the techniques described in connection with FIGS. 2, 3, 4, 5, 6, and 7 are applicable to this configuration 600.

It is also within the scope of the invention to provide a "mixed" optical system having a combination of conventional refractive lenses and binary refractive lenses. For example, the lens member 6
08 can be formed as a conventional refraction lens etched using a diffractive optical pattern.

FIG. 14 shows a configuration 700 similar to the configuration 600 of FIG. 13, in which a package 720 (similar to the package 620) or the like is used for the substrate 7
02 supports a lens member 708 (the array of photosensitive members on the surface of the die or substrate does not show this). However, the substrate 702 is also provided with an integral optical member 788 on its surface. Two types of transformations are possible. That is, (1) the lens member 708 can be a conventional refracting lens, and the optical member 788 integrated with the substrate is the diffractive member (for example, the lens bodies 108, 308, 408, and And large lens member 508), or (2) lens member 708 is a diffractive member (e.g., lens body 108, 3) as previously described.
08, 408 and any of the larger lens members 508) and the optical member 78.
8 can be a conventional refractive lens mounted on the surface of the substrate 702. Furthermore, the techniques described in connection with FIGS. 2, 3, 4, 5, 6, and 7 are applicable to this configuration 700.
In this way, the "mixed" optics (lens member 70
8 and the optical member 788) can be designed to eliminate spherical aberration and / or chromatic aberration. The filter can also be used to remove light having wavelengths associated with chromatic aberration that cannot be corrected by using "mixed optics".

For monochromatic images, the arrangement just described is generally most suitable. On the other hand, there is a demand for an executable structure for color images. Color images can generally be processed using a three-primary system. The three primary colors correspond to different colors of light, such as red (R), green (G), and blue (B). Each system consists of a lens, a filter and an associated photodetector (array). Not surprisingly, these triples of elements are more expensive than a single system.

FIG. 15 shows a configuration 800 suitable for color images. For example, an array of photosensitive members 802 is formed on the substrate 8 in the same manner as the photosensitive member 102.
Align on surface 04. However, this configuration 8
No. 00, three sets of closely grouped photosensitive members (“triple members”) 802a, 802b, 80 at each array location instead of a single photosensitive member 102.
2c is provided. 4 rows x 4 for clarity
An array of columns is shown. Optical transmission layer 806 (optical transmission layer 1
06) and the photosensitive triple members 802a, 802b, 8
It is formed on the upper layer of 02c. In this example, there is one lens body 808 for each "triple member" 802a, 802b, 802c of the photosensitive member. Lens body 808 is preferably diffractive and is designed to have different focal points for different wavelengths of light. For example, red (R) light is a triple-member photosensitive member 802a.
And the green (G) light converges on the three-layer photosensitive member 802.
Then, the light of blue (B) is converged on the photosensitive member 802c of the triple member. In this way, it is possible to form a color image. The techniques described above for the staggered structure (such that each triple member 802a, 802b, 802c represents a pixel of the incident image),
That is, a technique of a masking layer and a transparent layer sandwiched between the light transmission layer 806 and the substrate 804, a technique of supporting a lens structure or another lens structure in a package, a technique of providing a “mixed” optical system, etc. Can be applied to the technique of providing three groups of photosensitive members at the position of the array (pixel).

FIG. 16 shows a structure 900 of a solid-state image sensor capable of processing a color image. In the structure 800 of FIG. 15, a single substrate (die) and a triple member of a photosensitive member are adopted, but in this structure 900, three solid-state image sensors 902, 904, and 906 are adopted, and respective solid-state images are adopted. The sensor is suitable for detecting monochromatic images. Each solid-state image sensor 9
02, 904, and 906 are formed in the same manner as the sensor 100 (solid-state image sensor 100) of FIG. 1 (the modified version of the embodiment of FIG. 1 is equally applicable). Image 910 through beam splitter 912 by suitable optics (not shown).
("A") converges. Beamsplitter 912 is preferably a diffractive optical system designed to direct different wavelengths of light at different angles. For example, beam splitter 912 directs red (R) light to solid-state image sensor 902, green (G) light to solid-state image sensor 904, and blue (B) light to solid-state image sensor 906. The beam splitter 912 may include solid-state image sensors 902, 904, 90 as shown.
It can be designed to accommodate 6 linear planar configurations. Alternatively, instead of this, as shown in FIG. 17, three solid-state image sensors 902 ′, 90
By arranging 4 ′ and 906 ′ in a plane in a triangular (equal triangular) pattern, the beam splitter 9
12 ′ to solid-state image sensors 902 ′ and 9 respectively
The angles to 04 'and 906' can be the same and the directions can be different. Alternatively, instead of FIG.
As shown in FIG. 3, three solid-state image sensors 902 ″,
By aligning 904 ", 906" in an arcuate linear array, the distances from the beam splitter 912 "to the solid-state image sensors 902", 904 ", 906", respectively, can be made equal. This distance corresponds to the focal length of the lens (in the usual sense of the term). Instead, this distance is a predetermined mapping (mappi) of the image onto the solid-state image sensor.
ng) is sufficient. This mapping can be a one-to-one mapping, or alternatively is sufficient for use in combination with compression or decompression algorithms. The term "focal length" as defined for each embodiment of the present invention should be construed to include both these definitions in addition to its "focal length" in the normal sense.

The three solid-state image sensors in any of the embodiments shown in FIGS. 16, 17 and 18 are
It can be aligned with a suitable mounting substrate. For example, the three solid-state image sensors of FIGS. 17 and 18 can be arranged in a package similar to that of FIG. 13 or 14. For example, the optical member (lens member 708) in FIG.
Each of the three solid-state image sensors has an integral converging optical system.
This can be placed in the package cavity (in a manner similar to 08).

FIG. 19 shows the image sensing array 10.
A chip 1000 with 01 is shown. In the embodiment shown in FIG. 19, chip 1000 also includes a logic array 1002 for processing the signals output by image sensing array 1001. Logical array 1002
Can be, for example, an embedded array as disclosed in US patent application Ser. No. 07 / 596,680. The chip 1000 also includes the image sensing array 100.
1 or a memory array 1003 for storing the signals output by the logic array 1002.
In one embodiment, memory array 1003 can be a "hidden" cache memory.

FIG. 20 is a sectional view showing a method of forming a chip according to an embodiment of the present invention. A first light transmission layer 1103, such as spin-on glass, a second light transmission layer 1102, such as pyrolytic silicon dioxide, and a photoresist layer 1101 are sequentially used to cover a substrate 1104. Photoresist layer 1101 is exposed and developed by conventional techniques. Next, the photoresist layer 1
The second light transmission layer 1102 is etched by using 101 as a mask. Any suitable etching technique can be used. When vertical sidewalls are required, reactive ion etching techniques can preferably be used. Wet chemical etching, either alone or in combination with reactive ion etching, can also be used to form a more circular geometry at appropriate sites. In some embodiments, a laser beam can be used to improve the shape of the lens and to reduce defects in the shape of the lens that are detected during testing. If desired, the entire lens can be laser shaped. This method eliminates the need for masking and etching, but reduces throughput.

The refractive lens used in accordance with the present invention is
It can be manufactured by a suitable method. In one embodiment of the invention, such lenses are molded by chemical mechanical polishing.

The thus molded product is shown in FIG. In FIG. 21, layer 1202 represents the second light transmission layer that has undergone the coating and etching steps. In FIG. 21, the second light transmission layer 1202 is formed as a Fresnel lens structure or a binary lens structure. The first optical transmission layer 1203 includes the substrate 12
There is a gap formed with 04. This gap allows the lens to focus an image on an appropriate area of the substrate 1204 having one or more image sensing devices.

It is within the purview of those skilled in the art to which the present invention pertains to implementing monochromatic and color image solid state image sensors using diffractive optics in accordance with the techniques and configurations described above. Modifications that will be apparent from a review of the disclosure are within the scope of the invention. Accordingly, the invention is not limited to that described herein, but rather is defined by the claims and their equivalents.

[0066]

As described above, according to the present invention, since the light transmission layer capable of converging light is provided on the array of the photosensitive members arranged on the surface of the substrate, an improved solid-state image sensor is provided. be able to.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a basic solid-state image sensor according to the present invention.

FIG. 2 is a plan view of a surface of a substrate having an array of solid-state image sensors.

FIG. 3 is a plan view of another example of the surface of a substrate having an array of photosensitive members.

FIG. 4 is a plan view of yet another embodiment of the surface of a substrate having an array of photosensitive members.

FIG. 5 is a diagrammatic explanatory view in which a lens body and a photosensitive member are physically displaced from each other.

FIG. 6 is a schematic explanatory view of another embodiment in which the lens body and the photosensitive member are physically displaced from each other.

FIG. 7 is a diagrammatic explanatory view in which the lens bodies and the photosensitive member are provided with an apparent shift (rather than physically).

FIG. 8 is a partially cutaway perspective view of another embodiment of the present invention.

FIG. 9 is a partially cutaway perspective view of still another embodiment of the present invention.

FIG. 10 is a side view of still another embodiment of the present invention.

FIG. 11 is a side view of still another embodiment of the present invention.

FIG. 12 is a perspective view of still another embodiment of the present invention.

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

FIG. 14 is a sectional view of still another embodiment of the present invention.

FIG. 15 is a partially cutaway perspective view of still another embodiment of the present invention.

FIG. 16 is a schematic explanatory view of still another embodiment of the present invention.

FIG. 17 is a schematic explanatory view of still another embodiment of the present invention.

FIG. 18 is a schematic explanatory view of still another embodiment of the present invention.

FIG. 19 is a schematic explanatory view of still another embodiment of the present invention.

FIG. 20 is a schematic explanatory view of still another embodiment of the present invention.

FIG. 21 is a schematic explanatory view of still another embodiment of the present invention.

[Explanation of symbols]

100 solid-state image sensor 102, 102 ', 102 ", 102a, 102b, 1
02c, 102d, 102e, 102f, 102g, 1
02h, 102i Photosensitive member 103 Central region 104, 104 ', 104 "Substrate 106 Optical transmission layer 108, 108a, 108b, 108c, 108d, 1
08e, 108f, 108g, 108h, 108i Lens body (lens member) 200 Configuration 210 Configuration 220 Configuration 300 Configuration 302 Photosensitive Member 304 Substrate 306 Light Transmission Layer 308 Lens Body 310 Masking Layer 312 Opening (Hole) 400 Configuration 402 Photosensitive member 404, 404 ', 440 "Substrate 406 Upper layer including lens body 408 406', 406" Light transmission layer 408 Lens body 410 Light transmission layer 420 Structure 440 Structure 442 Masking layer 444 Light transmission isolation layer 500 Structure 502 Photosensitive member 504 Substrate 506 Light transmission layer 508 Large lens member 600 Configuration 602 Substrate 608 Lens member 620 Package 622 Side wall of package body 700 Configuration 702 Substrate 708 Lens member 720 Package 788 Optical member 8 00 configuration 804 substrate 802a, 802b, 802c photosensitive member 806 light transmission layer 808 lens body 900 configuration 902, 902 ', 902 ", 904, 904', 90
4 ″, 906, 906 ′, 906 ″ solid-state image sensor 910 image 912, 912 ′, 912 ″ beam splitter 1000 chip 1001 image sensing array 1002 logical array 1003 memory array 1101 second photoresist layer 1102 second light transmission layer 1103 first Optical transmission layer 1104 substrate 1202 second optical transmission layer 1203 first optical transmission layer 1204 substrate

Claims (18)

[Claims] 1. A substrate, an array of photosensitive members disposed on a surface of the substrate, and an optical transmission layer above the array, adjacent to the array, and capable of converging light on the array. A solid-state image sensor having. 2. The solid-state image sensor according to claim 1, wherein the light transmission layer has a Fresnel lens. 3. The solid-state image sensor according to claim 1, wherein the light transmission layer has a binary lens. 4. The solid-state image sensor according to claim 1, wherein the light transmission layer has a convex lens. 5. The solid-state image sensor according to claim 1, wherein the light transmission layer has a concave lens. 6. The solid-state image sensor according to claim 1, wherein the light transmission layer is divided into a plurality of sub layers. 7. The solid-state image sensor according to claim 6, wherein the sub-layers have different structures. 8. The solid-state image sensor according to claim 1, further comprising an array of logic elements on a surface of the substrate. 9. The solid-state image sensor according to claim 8, further comprising an array of memory devices on a surface of the substrate. 10. The solid-state image sensor according to claim 1, further comprising an array of memory devices on a surface of the substrate. 11. The solid-state image sensor according to claim 1, wherein the light transmission layer has only one lens. 12. The solid-state image sensor according to claim 1, wherein the lens focuses light on at least three of the photosensitive members. 13. A light transmission layer having a substrate, an array of photosensitive members disposed on the surface of the substrate, and a Fresnel lens or a binary lens located above the array and capable of focusing light on the array. A solid-state image sensor having: 14. The solid-state image sensor according to claim 13, further comprising a refraction lens arranged to correct chromatic aberration generated by the Fresnel lens or the binary lens. 15. The solid-state image sensor according to claim 13, further comprising a filter. 16. The solid-state image sensor according to claim 15, wherein the filter absorbs light having a wavelength that is not converged on the substrate due to chromatic aberration. 17. The solid-state image sensor according to claim 16, further comprising a refracting lens arranged to correct chromatic aberration caused by the Fresnel lens or the binary lens. 18. A substrate, an array of photosensitive members disposed on the surface of the substrate, an optical member, and packaging means for holding the substrate and holding the optical member on the surface. A solid-state image sensor having.