JPS6329415B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to solid-state color imaging devices, and more particularly to solid-state color imaging devices that utilize multiple photosensitive layers stacked on a solid substrate to eliminate the need for multicolor filters.

A well-recognized goal in the field of solid-state color imaging devices is to create solid-state color imaging devices that are extremely light sensitive and produce sharp images while having low manufacturing costs. Many different types of solid state color imaging devices have been created with this goal in mind.

In one example of such an imaging device, arrays of full-color imaging elements are made color selectively sensitive by a composite array of color filters disposed above the arrays. The highly efficient construction of such a filter array maximizes the amount of useful information based on human vision about subtle differences in color. Such filter arrangements are described, for example, in U.S. Pat. No. 3,971,065 issued July 20, 1976 to Bayer;
No. 4,047,203 issued September 6, 1977 to Dillon. However, the resolution inherent in such an array is not only limited by the number of imaging elements that can be placed in the array, but is further limited because only a portion of each element in the array contributes to the fine resolution. The spatial resolution of an array of color imaging elements of such a composite filter is therefore optimized for a particular structure, but is not as high as a monochromatic imaging array of the same number of elements.

British Patent No. 2029642 and Japanese Patent Publication No. 55-39404
Another structure proposed in No. 55-277772, No. 55-277773, No. 51-95720 is made such that a photosensitive element is superimposed on an information transfer device or solid substrate that can perform the switching function. .
This substrate is a MOS switching device or a CCD (charge coupled device) switching device. Such elements are described in detail in GB 2029642, the contents of which are hereby incorporated by reference. Such a structure has a potentially higher sensitivity due to the larger photosensitive area than a typical imaging device in which the photosensitive element is placed at the same height as the information transfer device. However, such devices must utilize multicolor filters, and the reduction in resolution is comparable to the conventional solid-state imaging devices described above. Furthermore, to create such a structure, the color filters must be arranged in a specific pattern over the image sensor, which makes alignment and combination of the color filters difficult, resulting in the difficulty of such devices. Manufacturing is complicated and expensive.

A technique for removing color filters with a vidicon is described in U.S. Pat. No. 3,617,753 to Kato et al.
The vidicon includes a conventional semiconductor layer with a substrate over a number of pn diodes that store electrical signals representative of light intensity. An electron beam scans the pn diode to retrieve the video information. By gradating the thickness of the semiconductor substrate through which the light that reaches the PN diode passes, light of different wavelengths hits the PN diode depending on the size of the gradation. In this way different groups of pn diodes can accumulate different colors of light. Alternatively, by forming the pn diodes at non-uniform depths from the surface, the thickness of the substrate can be substantially stepped. In another embodiment, solid state scanning can be used instead of electron beam scanning. There, junction devices and MOS
A device is utilized for each pixel, and selective etching of the substrate results in non-uniform distances between the photosensitive surface of the semiconductor substrate and the pixel bonding device. The disclosed device is not flattened by a stepped or truncated shape and does not have the advantages offered to devices that utilize semiconductors as photoresponsive elements.

Solid state color image sensor arrays have been developed with potential resolution equal to that of monochromatic arrays of the same size. Such an image sensor
The array has a plurality of stacked channels (eg, three channels stacked for a three-color device), each channel having a different spectral response due to different absorption of light by the semiconductor material. (UK PO91EF, Hampshire,
Havant, Honeywell (Hampshire, Havant,
See Research Publications, Volume 172, August 1978, Publication No. 17240, entitled "Color Responsive CCD Imaging Devices," available from Industrial Opportunities Ltd., Honeywell. thing. ) However, due to the need to overlap the three channels,
Manufacturing such devices requires extremely complex and expensive methods. CCDs (charge-coupled devices) are complex and expensive to manufacture because the channels carrying the information signal must be carefully created under strict constraints. Although it is possible to create a single channel on a substrate, overlaying another channel on top of it is complex and difficult.

Devices such as those described in the aforementioned Publication No. 17240 suggest that it is possible to create a large number of different channels in a silicon crystal that are stacked, which can serve as a stacked multi-channel color imaging device. There is. However, in addition to being expensive and complex to make as mentioned above, the color separation and selectivity of such devices is poor due to the inherent limitations of the materials used. The materials used to make such devices must have good single-crystal properties in addition to color-selective photosensitive elements to act as CCD channels.

As previously mentioned, there is a need in the industry for solid state color imaging devices that are extremely light sensitive and provide sharp image resolution. Utilizing a device in which a multicolor filter is superimposed on an array of imagers, the resulting image is
As described in US Pat. No. 3,971,065, they have low resolution and low selectivity, and are complex and expensive to manufacture due to the need for precise placement of multicolor filters. Increased selectivity can be achieved by utilizing a device in which a photosensitive element is superimposed on an information transfer device, as described in GB 2029642. However, such devices still have some resolution limitations because they must use multicolor composite filters that also increase manufacturing complexity and cost. By utilizing a device with a sensor array of multiple superimposed channels, it is possible to obtain a resolution equal to that of a monochromatic array. However, in order to stack three channels on top of each other, complex and expensive manufacturing techniques must be utilized.

The present invention utilizes multiple photosensitive layers stacked on top of each other and on top of the substrate to increase sensitivity. Additionally, the present invention does not require multicolor composite filters since each photosensitive layer detects a different color of light. A device according to the invention has a resolution similar to that of a monochromatic array of the same size, and can be manufactured using simple, common, and inexpensive techniques.

The present invention provides a solid state color imaging device that can be manufactured using simple, inexpensive and conventional techniques such as conventional vacuum deposition techniques and sputtering techniques. This device is extremely sensitive to light and produces images with desirably high resolution given the characteristics of the human eye. The photodetection area of each color element in the matrix is three times the area of a solid-state imaging device of the same size but with one photoconductive layer and one multicolor filter.
It can be doubled. The image resolution is also comparable to that of conventional monochromatic solid-state imaging devices with the same number of elements.

A device according to the invention consists of a solid-state substrate for handling charge and a plurality of photosensitive layers superimposed on the solid-state substrate for detecting light. The solid-state substrate is a CCD that can be distinguished from the superimposed channel information device.
Any type of two-dimensional information device such as (charge-coupled device) or MOS may be used. Each of the photosensitive layers stacked on top of each other on a solid substrate consists of three sublayers: a top continuous transparent electrode layer, a mosaic pattern of back electrodes, and a photosensitive sublayer disposed therebetween. . The back electrode of each sublayer is electrically connected to a solid substrate, such as the source or drain terminals of a MOS, CCD, or other switching device. Each of the photosensitive layers is electrically insulated from the other layers and
It is electrically isolated from the solid state substrate at all points except through electrical connections.

A primary object of the present invention is to provide a solid state color imaging device consisting of a solid state substrate on which a plurality of photosensitive layers are superimposed, each photosensitive layer electrically connected to the substrate from which the charge received can be read out. Each successive photosensitive layer is sensitive to and absorbs a wider range of light.

Another object of the invention is to provide a solid state color imaging device that can be manufactured without the need for multicolor filters.

Yet another object of the invention is to provide a solid state color imaging device that is highly sensitive to light.

Yet another object of the invention is to provide a solid state color imaging device capable of producing images with high resolution.

Yet another object of the invention is to provide a solid state color imaging device that is simple and inexpensive to manufacture.

The foregoing and other objects and advantages of the present invention will become apparent from the foregoing and other objects and advantages of the invention will be found in the details of construction and use hereinafter described in detail with reference to the accompanying drawings, in which like numerals indicate like parts throughout the drawings and which form a part of this specification. Those skilled in the art can understand this by reading the law.

Before describing implementations of solid state color imaging devices of the present invention, it is to be understood that the present invention is not limited to the particular arrangement of components shown, as such devices may be modified. be. Furthermore, the terms used in this specification are used to describe specific embodiments, and are not used in a limiting sense.

Referring now to FIG. 1, a conventional solid state color imaging device of the type having a photosensitive element superimposed on a substrate is shown. FIG. 1 is an exploded perspective view of a conventional solid-state color imaging device. Board 2
A photosensitive layer 3 is overlaid on the surface. The board 2 has many
MOS switching elements 6, 7, 8, 9, 10,
Contains 11. FIG. 1 shows only a portion of what such an imaging device would include. In fact, imaging devices include thousands of MOS elements. The elements 6, 7, 8, 9, 10 and 11 are used for various switching and transfer functions, for example in connection with red, green, blue, blue, red and green light respectively. Each of elements 6-11 includes a source terminal 12 and a drain terminal 13.

The photosensitive layer 3 consists of three sublayers which will be described below. Bottom layer or mosaic electrodes on the bottom dorsal layer 3
The innermost sublayers of all are electrically connected to elements 6-11. Layered on the photosensitive layer 3 are elements 6, 7, 8, 9, 10, 1, respectively.
1 corresponding to filter elements 14, 15, 16,
17, 18, 19. Filter element 14-
19 is used to prevent all light except monochromatic light from passing through. Therefore, for example,
Corresponding to the switching and transfer functions of the aforementioned elements 6-11, filter element 14 is used to block all light except red light, and filter element 15 is used to block all light except green light. The filter 16 prevents all light except blue light from passing through.

Since the photosensitive function within the layer 3 is distinguished from the switching and transfer functions within the substrate 2,
The device shown in FIG. 1 is much more sensitive to light than conventional devices in which the photosensitive function is performed at the same level as the switching and transfer functions. However, the device shown in Figure 1 still requires the use of multicolor filter elements 14-19, and since such filter elements require precise placement, the manufacture of this device is somewhat expensive. becomes. Filter element 14
-19 are photosensitive parts 20, 21, 22, 23, 24, respectively formed by back electrodes;
It is used to block the light before it reaches 25.

The combination of each MOS element 6-11, photosensitive portion 20-25 and filter 14-19 forms what is known in the art as a pixel. Therefore, the device portion shown in FIG. 1 shows six pixels. The present invention eliminates the need for multicolor filters while
Devices can be manufactured that utilize the same size substrate 2 containing six pixels or two sets of pixels as described below.

Referring now to FIG. 2, there is shown an exploded perspective view of a device according to the present invention. This imaging device includes MOS elements 6, 7, 8, 9, 1
0, 11 includes a substrate 2 disposed thereon. The photosensitive layers 3, 4, 5 are superimposed on the substrate. layer 3,
Each of 4 and 5 consists of a plurality of sublayers, which will be described in more detail in connection with FIG. FIG. 2, like FIG. 1, shows only a small portion of an imaging device made up of thousands of identical parts.

Layer 3 includes photosensitive elements 26 and 27, layer 4 includes photosensitive elements 28 and 29, and layer 5 includes photosensitive elements 30 and 3.
Contains 1. Each of the elements 26-31 is connected to the substrate 2.
Connected to one of the MOS elements. element 26,
28, 30 are stacked on top of each other like elements 27, 29, 31. Although it will be easier to understand the invention if layers 3, 4, 5 are described as comprising photosensitive elements 28, 29, etc., in each layer the upper electrode sublayer and photoconductive sublayer pass through the holes. It should be understood that a continuous layer is preferred except where the layer is removed. The bottom mosaic electrode layer is not continuous and forms the boundaries of each photosensitive element.

Elements 26, 28, and 30 are each MOS element 1
Connected to 0, 6, and 9. MOS element 10,
The combination of 6, 9 and the photosensitive elements 26, 28, 30 is
They constitute what is called a set of pixels.
Two sets of pixels are shown in FIG. The MOS elements are arranged in an L-shaped pattern as shown in FIG. However, MOS elements can be arranged in any number of patterns, such as in a straight line.
It can be connected to the back electrode in a variety of different ways.

Next, layers 3, 4, and 5 will be explained in detail with reference to FIG. 3, which is a longitudinal cross-sectional plan view of the imaging device of the present invention. As already pointed out, each photosensitive layer 3-5
consists of three sublayers. Layer 3 is small layer 32, 33,
Contains 34. Layer 4 includes sublayers 35, 36, 37 and layer 5 includes sublayers 38, 39, 40. Layer 3 is insulated from substrate 2 by an insulator layer 41 . Layer 3 is insulated from layer 4 by an insulator layer 42, and layer 4 is insulated from layer 5 by an insulator layer 43. Therefore, each of the layers 3-5 is electrically insulated from each other and is connected to the electrical wiring 44, 4.
5, 46 at all points except for the point via
insulated from

The photosensitive layer 3 comprises a top transparent electrode sublayer 34 and a bottom mosaic-like transparent electrode sublayer 32 . A sublayer 33 of photoconductive material is disposed between sublayers 32 and 34. Layers 4 and 5 contain the same components as layer 3.
However, the respective bottom tessellated electrode sublayers 35 and 38 within layers 4 and 5 must be transparent, unlike the opaque electrode sublayer 32 of layer 3. Additionally, each of layers 3, 4, 5 is made sensitive to and capable of absorbing a different color of light, as will be explained in detail in connection with Figures 5-5C.

By constructing the device as shown in FIGS. 2 and 3, it is possible to eliminate the need for a complex multicolor filter array. More specifically, devices based on the present invention are disclosed in U.S. Pat. No. 3,971,065 and U.S. Pat.
Filters such as those disclosed in No. 4047203
Does not require array structure. Because the device according to the invention does not require a composite (multicolor) color filter on top of the solid state device, the device according to the invention can be manufactured relatively easily at relatively low cost.

Although the device according to the invention can operate without the need for any filters, it is possible to utilize one broadband type filter superimposed on the outermost photosensitive layer 5. Such filters can be designed to block light invisible to the human eye, such as light with wavelengths below 4000 Å or above 7700 Å, ie, ultraviolet light and infrared light.

Referring now to FIG. 4, a perspective view of an imaging device according to the present invention can be seen. The light impinges on the top surface of the outermost layer 5, as shown in FIG. As will be explained in more detail below, some of the light is absorbed by layer 5, the unabsorbed light hits layer 4 for further absorption, and the remaining light hits layer 3. The back electrode sublayer 33 of layer 3 is opaque so that no light falls on the base 2.

The operation of the imaging device of the present invention will be described in detail with reference to FIG. 5 in combination with FIGS. 5a-5c.
FIG. 5 is a longitudinal cross-sectional view of the same device shown in FIG. 3, but simplified such as not showing the sublayers. Figures 5a, 5b and 5c are graphs plotting both wavelength versus absorption and wavelength versus photoconductivity for light absorbed and detected within layers 5, 4 and 3, respectively.

When light strikes layer 5 in the wavelength range to which layer 5 responds, the resistance of photoconductive sublayer 39 (see FIG. 3) decreases in a particular element 30 (see FIG. 2). This reduced resistance can be detected and recorded electrically by utilizing electrode sublayers 40 and 38 in combination with MOS elements 9 inside substrate 2. The particular method of recording a reduction in electrical resistance performed in conjunction with the detection of light is not part of this invention and is well known to those skilled in the art. This reduced resistance represents the intensity of the blue light impinging on the elements 30 of layer 5 (see FIG. 5a). Moreover, layer 5 absorbs light only in the blue region, as shown by the absorption curve in FIG. 5a. The light passing through layer 5 only contains the green and red parts of the spectrum. Layer 5 is
All light having a wavelength of 5000 Å or less is absorbed, allowing the remaining light to reach layer 4. Furthermore, layer 5 is sensitive to light having a wavelength of 5000 Å or less.

When layer 4 is exposed to light in the wavelength range to which layer 4 responds, the resistance of photosensitive sublayer 36 (see FIG. 3) increases as element 2
8 (see Figure 2). This decrease in resistance causes the current to change as described above. Therefore, the green light impinging on the photosensitive element 28 can be detected in relation to the MOS element 6. Layer 4 also absorbs light in the green region, as shown by the absorption curve for layer 4. The material inside layer 4 actually tries to absorb blue and green light, but the blue light is absorbed or blocked by layer 5. Therefore, the combination of layers 4 and 5 blocks all of the blue and green light, allowing only the red light to pass through. Layer 4 blocks light having a wavelength of 6000 Å or less and is sensitive to light having a wavelength of 6000 Å or less. However, since the light having a wavelength of 5000 Å or less is blocked by the layer 5, the layer 4 is exposed to light having a wavelength between 5000 Å and 6000 Å, that is, green light, and the layer 4 reacts to this green light.

As shown in Figure 5c, layer 3 absorbs all visible light and is more or less sensitive to all visible light. However, layer 3 is most sensitive to light in the red part of the spectrum. As already explained, layer 5
already absorbs blue light and layer 4 already absorbs green light. Therefore, only red light hits layer 3. When red light strikes layer 3, the resistance of photosensitive sublayer 33 (see FIG. 3) decreases in certain elements 26 (see FIG. 2). This reduction in resistance causes the current to change as described above, thereby allowing the detection of light by electrical impulses. The back electrode sublayer 32 of layer 3 (see FIG. 3) is opaque so that no light falls on the base 2. The back mosaic electrode sublayer 32 is the only opaque sublayer of each layer of the imaging device. All other sublayers are transparent to at least the wavelength of light that is intended to pass to the next sublayer.

By utilizing the layers 3, 4, 5 with specific absorptive and photoconductive properties as described above, it is possible to precisely detect the light that falls on any particular area of the imaging device and to adjust the wavelength of the light that falls on that area. , and therefore color, can be measured. The intensity of light impinging on each of the photosensitive elements can also be measured by the degree of change in resistance of the respective photosensitive layer. Layers 3, 4, 5 are made in such a way that small variations in resistance can be measured, so that the relative intensity of light of any particular wavelength striking any particular element of the photosensitive layer will be It can be detected and recorded by means.

The color imaging devices disclosed herein can be manufactured in a variety of different embodiments. Although structural details are not shown, the imaging array can be manufactured as shown in the aforementioned British patent. However, modifications are required to provide three photosensitive layers and an opening for connecting the bottom electrode of each photosensitive layer to a MOS device on the semiconductor substrate.

The embodiments shown in Figures 2, 3, 4, and 5 and described in connection with Figures 5a-5c are considered preferred embodiments of the invention. The top layer 5 detects and absorbs blue light, the middle layer 4 detects and absorbs at least green light, and the bottom layer 3 detects at least red light and absorbs all light. By manufacturing layers 4 and 5 to be able to detect and absorb light, these layers act as both sensors and filters. Therefore, the need for multicolor filters that must be arranged in a complex array is eliminated, while the ability to detect different colors of light is retained.

The device shown in FIG. 5 and described in connection with FIGS. 5a-5c can be manufactured in various ways to achieve different end results. When manufacturing a device intended to work in this manner, the material within each of the photosensitive layers, as well as the insulating material within the insulating layer, must be manufactured in a specific manner.

The insulating material inside the layers 41, 42, 43 is
Choose from a number of electrical insulating materials such as SiO ₂ , Si ₃ N ₄ , polyimide, polyamide, photocurable resins or other known organic polymers.

The topmost photosensitive layer 5 is sensitive to blue light and is made of a material selected from the group consisting of CdS, ZnCdS, ZnSeTe. Layer 4, which is sensitive to and absorbs both blue and green light, but absorbs only green light since blue light is blocked by layer 5, is made of amorphous selenium, CdSe, or GaAsP. . The lower layer 3 is a dorsal mosaic electrode sublayer 32
Because it is opaque, it is sensitive to blue, green, and red light and absorbs light of all colors. Furthermore, since blue and green light are blocked by layers 4 and 5, layer 3 detects only red light. Layer 3 is
Made from a material selected from the group consisting of GaAIAs, GaAsP, ZnCdTe, CdTe, and amorphous hydrogen silicide.

Depending on the particular type of photosensitive layer utilized and how the device is used, different voltages may be utilized for device operation. Additionally, different voltages can be utilized in conjunction with each of the photosensitive layers depending on the particular result desired.

A solid state color imaging device according to the present invention has been described in what is considered to be the most practical and preferred embodiment. References to specific materials, specific terminology, and specific sensitivity of the photosensitive layer to specific wavelengths or colors of light are made solely to disclose preferred embodiments. It is also recognized that modifications may be made to such embodiments within the scope of the invention, and changes may occur that occur to those skilled in the art upon reading the embodiments.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view of a conventional solid-state color imaging device showing a photoconductive layer stacked on a substrate, and FIG. 2 is an exploded perspective view of a solid-state color imaging device of the present invention showing a three-layer, four-story structure. FIG. 3 is a longitudinal sectional view of the solid-state color imaging device of the invention, FIG. 4 is a schematic perspective view of the solid-state color imaging device of the invention, and FIG. 5 is a longitudinal sectional view of the solid-state color imaging device of the invention.
Figures 5a, 5b and 5c show wavelength versus absorption and wavelength versus photoconductivity for light absorbed and detected within the outermost, middle and innermost layers, respectively, of the solid state color imaging device of the present invention. This is a plotted graph. 2...Substrate, 3,4,5...Photosensitive layer, 6,7,
8, 9, 10, 11...MOS switching element,
26, 27, 28, 29, 30, 31...Photosensitive element, 32, 34, 35, 37, 38, 40... Electrode sublayer, 33, 36, 39... Photoconductive sublayer, 4
1, 42, 43...Insulating material, 44, 45, 46
……Electric wiring.

Claims (1)

[Scope of Claims] 1. A solid substrate comprising an array of electrical switching elements arranged in three sets, a layer of a first insulating material disposed on the substrate, and a layer of an insulating material superimposed on the first insulating material. a second photosensitive layer disposed on the first photosensitive layer; a second photosensitive layer superimposed on the second layer of insulating material; a third layer of insulating material disposed on top of the second photosensitive layer; and a third photosensitive layer superimposed on the third layer of insulating material, the first photosensitive layer being a transparent electrode layer; a back mosaic electrode layer; and a photoconductive layer disposed between the upper electrode layer and the back electrode layer; the layer is divided into an array of portions corresponding to the electrical switching elements of the substrate;
Each segmented portion of the back mosaic electrode sublayer is electrically connected to one of the three sets of electrical switching elements of the substrate, and the second photosensitive layer is connected to the upper transparent electrode sublayer. layer, a back mosaic electrode layer, and a photoconductive layer disposed between said top electrode layer and said back electrode layer; 1
is divided into an array of vertically corresponding portions of the photosensitive layer of the substrate, each portion of this back mosaic electrode sublayer being electrically connected to one of the three sets of electrical switching elements of the substrate. connected, the third photosensitive layer comprising a top transparent electrode layer, a back mosaic electrode layer, and a photoconductive layer disposed between the electrode layer and the back electrode layer. This back mosaic electrode sublayer is divided into an array of sections corresponding perpendicularly to the sections of the second photosensitive layer, each section of the back mosaic electrode sublayer corresponding to the three sections of the substrate. electrically connected to one of the set of electrical switching elements;
The photosensitive layer, the second photosensitive layer and the third photosensitive layer are sensitive to and absorb different ranges of the visible wavelength spectrum, thereby absorbing light from the three photosensitive layers. 3, characterized in that the electrical signal represents the light intensity of three different color ranges;
A solid-state color imaging device with a four-layer structure. 2. A patent characterized in that each of the layers arranged in sequence in the direction towards the solid substrate is arranged and manufactured in such a way that towards this direction the layers have wavelength-to-absorption characteristics which result in a layer absorbing a wider band of the optical spectrum. A solid-state color imaging device having a three-layer, four-story structure according to claim 1. 3. Said third photosensitive layer is sensitive to and absorbs light in the blue region of the visible wavelength spectrum, and said second photosensitive layer is not sensitive to light in the red region of the visible wavelength spectrum, but absorbs at least green light. Claim 1, wherein the first photosensitive layer is sensitive to light in the red region of the visible wavelength spectrum and absorbs this light. A solid-state color imaging device with a three-layer, four-layer structure. 4. The three-layer, four-story solid-state color imaging device according to claim 1, wherein the electric switching element arranged on the substrate is a MOS device. 5 The third photosensitive layer is CdS, ZnCdS, ZnSeTe
The second photosensitive layer is made of a photosensitive material selected from the group consisting of amorphous selenium, CdSe,
The first photosensitive layer is made of a photosensitive material selected from the group consisting of GaAsP, GaAlAs,
A solid-state color imaging device having a three-layer, four-layer structure according to claim 1, characterized in that it is made of a photosensitive material selected from the group consisting of GaAsP, ZnCdTe, CdTe, and amorphous hydrogen silicide. 6. A solid substrate consisting of a large number of electric switching elements arranged in three sets, and first, second and third photosensitive layers stacked on top of each other and arranged in a vertical direction on the solid substrate, The respective photosensitive layers together consist of a photoconductive sublayer, a transparent electrode sublayer laminated on top of the photoconductive sublayer, and a mosaic electrode sublayer laminated behind the photoconductive sublayer. , said back mosaic electrode sublayer is divided into an array of sections, each section of said first photosensitive layer mosaic electrode sublayer corresponding to a particular set of electrical switching elements of said solid substrate. each portion of the mosaic electrode sublayer of the second photosensitive layer is connected correspondingly to a specific other set of electrical switching elements of the solid substrate; each portion of the mosaic electrode sublayer is correspondingly connected to a particular further set of electrical switching elements of the solid substrate, and the three photosensitive layers are sensitive to mutually different ranges of the visible wavelength spectrum. and absorbing these ranges, so that the electrical signals received by each of the photosensitive layers represent the light intensities of three different color ranges, thereby forming a combined array of three types of pixel groups. A solid-state color imaging device having a three-layer, four-story structure. 7. A patent characterized in that each layer arranged in sequence in the direction towards the solid substrate is arranged and manufactured in such a way that towards this direction each layer has a wavelength-to-absorption characteristic which results in a layer absorbing a wider band of the optical spectrum. A solid-state color imaging device having a three-layer, four-story structure according to claim 6. 8. The three photosensitive layers are the outermost layer furthest from the solid substrate and sensitive to and absorbing light in the blue region of the visible wavelength spectrum, the outermost layer being insensitive to the red region of the visible wavelength spectrum but at least the green a central layer sensitive to and absorbing light in the region; and an innermost layer closest to said solid substrate and sensitive to light in at least the red region of the visible wavelength spectrum. A solid-state color imaging device having a three-layer, four-story structure according to Scope 6. 9. 3 according to claim 6, wherein the electric switching element arranged on the substrate is a MOS device or a CCD device.
A solid-state color imaging device with a four-layer structure. 10 a semiconductor switching matrix comprising a matrix of electrical switching elements, a plurality of first photoconductors responsive to absorbing light in a relatively lower band of the visible wavelength spectrum, at least a higher band than the first photoconductor; a plurality of second photoconductors responsive to and absorbing light; and a plurality of third photoconductors responsive to and absorbing at least a higher band of light than the second photoconductors; Said first
each of the photoconductors being electrically connected to a respective first plurality of said electrical switching elements for transmitting an electrical signal representative of the intensity of light to which said first photoconductor is sensitive to said electrical switching element. ,
The second photoconductor is electrically connected to each of the second plurality of electrical switching elements for transmitting to the electrical switching elements an electrical signal representative of the intensity of light to which the second photoconductor is sensitive. each of a third plurality of electrical switching elements for transmitting an electrical signal representative of the intensity of light to which the third photoconductor is sensitive to the electrical switching element; the first, second and third photoconductors constitute three superimposed layers of a solid-state imaging device, these three photoconductors being electrically connected to the light impinging on the solid-state color imaging device; first strikes the first photoconductor, the wavelengths of light that are not absorbed thereby strike the second photoconductor, and the wavelengths of light that are not absorbed thereby become the third light. each signal being superimposed on a structure such that it impinges on an electrical conductor, and thereby being switched by said first, second and third plurality of electrical switching elements, respectively.
A solid-state color imaging device with a three-layer, four-layer structure, characterized in that it represents light intensities of two different bandwidths. 11 Each of the first, second, and third photoconductors comprises a photoconductive layer having an upper electrode layer and a lower electrode layer, and the lower electrode layer is divided, and each divided portion is divided into the plurality of photoconductors. 11. A solid-state color imaging device having a three-layer, four-layer structure as claimed in claim 10, wherein the solid-state color imaging device forms one of the photoconductors. 12. A solid-state color imaging device with a three-layer, four-level structure according to claim 10, wherein the electric switching element is formed of a MOS device or a CCD device.