JP2003197884A - Solid-state detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a decrease in picture quality caused by scattering of read light entering a solid-state detector equipped with a photoelectric charge couple generating electrode and a photoelectric charge couple non-generating electrode. <P>SOLUTION: The solid-state detector 20 comprising a 1st conductive layer 21, a photoconductive layer 22 for recording, a charge transfer layer 23, a photoconductive layer 24 for reading, a 2nd conductive layer 25 equipped with the photoelectric charge couple generating electrode 26 composed of many linear electrodes 26a and the photoelectric charge couple non-generating electrode 27 composed of many linear electrodes 27a, etc., is provided with low- reflection-factor layers 40a and 40b on the top and reverse surfaces of each linear electrode 27a of the photoelectric charge couple non-generating electrode 27 to reduce scattered light (read light) reflected by each linear electrode 27a. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state detector having a power storage unit for accumulating as a latent image charge an amount of charge corresponding to a dose of irradiated radiation or a light amount of light emitted by excitation of the radiation. Is.

[0002]

2. Description of the Related Art Today, in radiography for the purpose of medical diagnosis and the like, charges obtained by detecting radiation are temporarily accumulated in a power storage unit as latent image charges, and the accumulated latent image charges represent radiation image information. Various image information recording / reading devices have been proposed that use a solid-state detector that converts and outputs an electric signal.
Although various types of solid-state detectors have been proposed for use in this device, reading light (reading electromagnetic wave) is applied to the detector from the viewpoint of the charge reading process of reading the accumulated charges to the outside. There is a light reading method of irradiating and reading.

The applicant of the present invention has disclosed, as a solid-state detector of an optical readout system, capable of achieving both high-speed response of readout and efficient extraction of signal charges, as disclosed in Japanese Patent Application Laid-Open No. 2000-105297.
No. 2000-284056, 2000-2
No. 84057, a first conductive layer having transparency to recording radiation or light emitted by excitation of the radiation (hereinafter referred to as recording light), and a recording photoconductive layer exhibiting conductivity by receiving recording light. , A charge transport that acts as a substantially insulator for a charge having the same polarity as the charge charged in the first conductive layer and as a substantially conductor for a charge having the opposite polarity as the charge of the same polarity Layer, a reading photoconductive layer that exhibits conductivity by being irradiated with reading light (reading electromagnetic wave), and a second conductive layer that is transparent to reading light, are stacked in this order for recording. We have proposed a solid-state detector that accumulates signal charges (latent image charges) carrying image information in a storage unit formed at the interface between the photoconductive layer and the charge transport layer.

Then, the above-mentioned Japanese Patent Laid-Open No. 2000-284056.
In Japanese Patent Laid-Open No. 2000-284057 and Japanese Patent Laid-Open No. 2000-284057, in particular, the electrode of the second conductive layer is a stripe electrode (photoelectric charge pair generating electrode) formed of a large number of linear electrodes transparent to the reading light, and the storage of electricity is also performed. The sub-stripe electrode (photocharge pair non-generating electrode), which is composed of a large number of linear electrodes for outputting an electric signal of a level corresponding to the amount of latent image charge accumulated in the area, is So that the stripe electrodes and the linear electrodes are alternately and parallel to each other,
A solid-state detector provided in the second conductive layer is proposed.

As described above, by providing the sub-stripe electrode composed of a large number of linear electrodes in the second conductive layer, a new capacitor is formed between the power storage unit and the sub-stripe electrode, and the storage light is generated by the recording light. It is possible to charge the sub-stripe electrodes with the charge reversing during the reading, which is the reverse charge of the latent image charges accumulated in the sub-stripe electrodes. As a result, the amount of the transport charge distributed to the capacitor formed between the stripe electrode and the power storage unit via the reading photoconductive layer is made relatively smaller than in the case where the sub-stripe electrode is not provided. As a result, it is possible to increase the amount of signal charges that can be taken out from the solid state detector to improve the reading efficiency, and to achieve both high-speed read response and efficient signal charge taking-out. It is like this.

Further, the applicant of the present invention has been described in the above-mentioned JP 2000-1.
In Japanese Patent Application No. 05297, etc., as one of the methods of reading the latent image charge accumulated in the solid-state detector, a detection amplifier is connected to each linear electrode forming a stripe electrode, and the longitudinal direction of the linear electrode is set to the sub-scanning direction. , The direction orthogonal to the longitudinal direction of the linear electrodes (arrangement direction of the linear electrodes) is the main scanning direction,
A method of scanning the stripe electrode side in the sub-scanning direction with a linear reading light extending in the main scanning direction (hereinafter also referred to as line light) to detect signal charges for each linear electrode (hereinafter referred to as line reading method). ) Is proposed.

In this line reading method, since parallel (simultaneous) reading is performed in the main scanning direction, the reading speed can be increased, and the distributed capacitance of each detection amplifier can be obtained by dividing the electrode into each linear electrode. Since the (load capacitance) is reduced, the S / N ratio can be improved, and furthermore, the latent image charge storage position can be roughly fixed at the disposition position of the stripe electrode, which enables structure-noise correction. It is an excellent method having various advantages such as.

[0008]

However, when the latent image charge is read from the solid-state detector having the stripe electrode and the sub-stripe electrode by the above-mentioned line reading method, the reading light emitted at the time of reading is the solid-state detector. There is a risk that it will be reflected and scattered by the stripe electrode or sub-stripe electrode, etc. inside, and the scattered reading light corresponds to the linear electrodes that compose the sub-stripe electrode on the reading light incident surface of the reading photoconductive layer. When it reaches the area to be discharged, discharge is generated there and the signal detection efficiency is reduced. Further, when the scattered reading light reaches an adjacent pixel area other than the reading pixel, discharge also occurs there, and as a result, the sharpness is lowered.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a solid-state detector capable of reducing deterioration in image quality caused by scattering of the reading light incident on the solid-state detector. It is intended.

[0010]

A first solid-state detector according to the present invention comprises a first conductive layer which is transparent to recording light,
A recording photoconductive layer that exhibits photoconductivity by being irradiated with recording light, a power storage unit that accumulates an amount of electric charge as a latent image charge according to the amount of recording light, and a light by receiving reading light. It is provided with a reading photoconductive layer exhibiting conductivity, a photocharge pair generating electrode composed of a large number of linear electrodes having transparency to the reading light, and a photocharge pair non-generating electrode composed of a large number of linear electrodes. , A second conductive layer in which a linear electrode of a photocharge pair generating electrode and a linear electrode of a photocharge pair non-generating electrode are alternately laminated in this order. It is characterized in that the generating electrode is provided with a low reflectance layer having a low reflectance characteristic with respect to the reading light on the upper surface and / or the lower surface.

In the first solid-state detector, the "low reflectance layer having a low reflectance characteristic with respect to the reading light" means a reflectance lower than the reflectance characteristic of the photocharge vs. non-generating electrode with respect to the reading light. It means a layer having characteristics.

The second solid-state detector of the present invention comprises a first conductive layer which is transparent to recording light and a recording photoconductive layer which exhibits photoconductivity when irradiated with the recording light. And a storage unit that accumulates an amount of electric charge as a latent image charge according to the amount of recording light, a reading photoconductive layer that exhibits photoconductivity by being irradiated with the reading light, and a transparency to the reading light. A photocharge pair generating electrode consisting of a large number of linear electrodes having
A photocharge pair non-generating electrode composed of a large number of linear electrodes,
A second conductive layer in which a linear electrode of a photocharge pair generating electrode and a linear electrode of a photocharge pair non-generating electrode are alternately arranged, and a light shield that shields the reading light with which the photoelectric charge pair non-generating electrode is irradiated. In a solid-state detector in which a film and a film are laminated in this order, the light-shielding film is provided with a low-reflectivity layer having a low-reflectivity characteristic with respect to read light on the upper surface and / or the lower surface. It is a thing.

In the second solid-state detector, the "low reflectance layer having a low reflectance characteristic with respect to the reading light" means a layer having a reflectance characteristic lower than that of the light shielding film with respect to the reading light. Means

In the present invention, the "solid state detector" is the first
Conductive layer, recording photoconductive layer, reading photoconductive layer and second
And a conductive layer are formed in this order, and a power storage unit is formed between the recording photoconductive layer and the reading photoconductive layer, and further other layers and micro conductive members (microplates) are provided. It may be formed by stacking layers.

As a method of forming the above-mentioned power storage unit, a method of providing a charge transport layer and forming the power storage unit at the interface between this charge transport layer and the recording photoconductive layer (Japanese Patent Laid-Open No. 2000- 105297, JP 2000-28
No. 4056), a method of forming a storage layer in the trap layer or at the interface between the trap layer and the recording photoconductive layer (for example, US Pat. No. 4,535,546).
No. 8), or a method of providing a minute conductive member or the like for concentrating and storing latent image charges (Japanese Patent Laid-Open No. 2000-2000)
(See Japanese Patent Publication No. 284057) and the like may be used.

Further, the "photoelectric charge pair generating electrode composed of a large number of linear electrodes having transparency to the reading light" is an electrode which transmits the reading light and generates a charge pair in the reading photoconductive layer. . The "photoelectric charge pair non-generating electrode" is an electrode for outputting an electric signal of a level corresponding to the amount of latent image charge accumulated in the electricity storage unit, and has a light shielding property against the reading light. However, when a light shielding film or the like having a light shielding property is provided between the photocharge pair non-generating electrode and the reading light irradiation means, the photocharge pair nongenerating electrode does not necessarily have the light shielding property. Here, the “light-shielding property” is not limited to the one that completely blocks the reading light and does not generate the charge pair at all, and the charge pair generated by the reading light even if it has some transparency to the reading light. Including items that do not pose a problem. Therefore, all the charge pairs generated in the reading photoconductive layer are not limited to the reading light transmitted through the photocharge pair generating electrode, and the reading light may be read through the reading light slightly passing through the photocharge pair non-generating electrode. It is assumed that charge pairs can be generated in the conductive layer.

The "reading light" may be any light that can move an electric charge in an electrostatic recording medium and electrically read an electrostatic latent image, and specifically, light or radiation. Etc.

When recording or reading a radiation image using the solid-state detector according to the present invention, for example,
As described in Japanese Patent Application Laid-Open No. 2000-284056, a recording method and a reading method using a conventional solid-state detector to which the present invention is not applied and the apparatus (image information recording / reading apparatus) are used as they are without changing. can do.

[0019]

In the solid-state detector according to the present invention, since the low reflectance layer is provided on the upper surface and / or the lower surface of the photocharge pair non-generating electrode or the light shielding film, the photocharge pair non-generating electrode or the light shielding film is incident. The read light can be suppressed from being scattered and reflected by the photocharge pair non-generating electrode or the light-shielding film, so that such reflected light is further reflected at other places and finally read by the photoconductive layer. Decrease in signal detection efficiency caused by incidence on the area corresponding to the photocharge pair non-generating electrode on the reading light incident surface of the layer, and sharpness of the read image caused by reaching adjacent pixel areas other than the pixel concerned. The decrease can be reduced.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a schematic configuration of a first embodiment of a solid-state detector of the present invention.
1A is a perspective view of the solid-state detector 20a, FIG. 1B is an XZ cross-sectional view of the Q arrow finger portion of the solid-state detector 20a, and FIG. 1C is an XY cross-sectional view of the P arrow finger portion of the solid-state detector 20a. is there.

This solid-state detector 20a generates a charge pair by receiving the irradiation of the first conductive layer 21 which is transparent to the recording light and the recording light which has passed through the first conductive layer 21 and becomes conductive. The recording photoconductive layer 22 which is present, acts substantially as an insulator against the latent image polar charge (for example, negative charge) in the charge pair, and has a transport polar charge (above-mentioned polarity opposite to the latent image polar charge). (For example, positive charge), the charge transport layer 23 acts substantially as a conductor, the reading photoconductive layer 24 that exhibits conductivity by generating a charge pair when irradiated with reading light, and a photocharge pair generation The second conductive layer 25 having the electrode 26 and the photocharge pair non-generating electrode 27, and the support 18 having transparency to the reading light are arranged in this order.
At the interface between the recording photoconductive layer 22 and the charge transport layer 23, a two-dimensionally distributed power storage unit 29 for accumulating the latent image polar charge carrying the image information generated in the recording photoconductive layer 22 is formed. It

As the support 18, a glass substrate or the like which is transparent to the reading light can be used. Further, in addition to being transparent to the reading light, it is more desirable to use a substance whose thermal expansion coefficient is relatively close to that of the reading photoconductive layer 24. For example, when a-Se (amorphous selenium) is used as the reading photoconductive layer 24, the coefficient of thermal expansion of Se is 3.68 × 10 ⁻⁵ / K @ 40.
Considering that the temperature is 1.0 ° C., the coefficient of thermal expansion is 1.0 to 10.
0 × 10 ⁻⁵ / K @ 40 ° C., more preferably 4.0.
Use a substance that is 8.0 × 10 ⁻⁵ / K @ 40 ° C.
As a substance having a coefficient of thermal expansion within this range, an organic polymer material such as polycarbonate or polymethylmethacrylate (PMMA) can be used. As a result, the thermal expansion of the support 18 as a substrate and the photoconductive layer for reading 24 (Se film) can be matched, and a large temperature cycle can be performed in a special environment, for example, during ship transportation under cold weather conditions. Even if received, thermal stress occurs at the interface between the support 18 and the reading photoconductive layer 24, and the two physically separate.
There is no problem of destruction due to the difference in thermal expansion, such as the reading photoconductive layer 24 breaking or the support 18 cracking. Furthermore, organic polymer materials have the advantage of being more resistant to impacts than glass substrates.

The material of the recording photoconductive layer 22 is a-
Se (amorphous selenium), PbO, PbI_Two  Etc.
Lead (II) oxide, lead (II) iodide, Bi₁₂(Ge, S
i) O ₂₀, Bi_TwoI_Three/ Organic polymer nanocomposite
Photoconductive material containing at least one of
Is appropriate.

For the material of the charge transport layer 23, the larger the difference between the mobility of the negative charge charged in the first conductive layer 21 and the mobility of the positive charge having the opposite polarity, the better (for example, 1
0 ² or more, preferably 10 ³ or higher) poly N- vinylcarbazole (PVK), N, N'-diphenyl -N, N'-bis (3-methylphenyl) - [1,1'-biphenyl] -4, Four'
An organic compound such as diamine (TPD) or discotic liquid crystal, or a polymer dispersion of TPD (polycarbonate, polystyrene, PUK), Cl of 10 to 20
A semiconductor material such as 0 ppm doped a-Se is suitable. In particular, organic compounds (PVK, TPD, discotic liquid crystal, etc.) are preferable because they have light insensitivity. Further, since the permittivity is generally small, the charge transport layer 23 and the reading photoconductive layer 24 have small capacities, and at the time of reading. The signal extraction efficiency of can be increased. It should be noted that "having light insensitivity" means that it exhibits almost no conductivity even when irradiated with recording light or reading light.

The material of the reading photoconductive layer 24 is a-
Se, Se-Te, Se-As-Te, metal-free phthalocyanine, metal phthalocyanine, MgPc (Magnesium ph)
talocyanine), VoPc (phaseII of Vanadyl phthal
Cyanine), CuPc (Cupper phtalocyanine), and the like, and a photoconductive substance containing at least one as a main component is suitable.

The thickness of the recording photoconductive layer 22 is 50 μm or more and 1000 in order to sufficiently absorb the recording light.
It is preferably not more than μm.

The charge transport layer 23 and the reading photoconductive layer 24 are also provided.
It is desirable that the sum of the thicknesses of and is less than or equal to 1/2 of the thickness of the recording photoconductive layer 22, and the thinner the thickness, the better the response at the time of reading. Is preferably 1/100 or less.

The material of each of the above layers is the first conductive layer 21.
Is charged with a negative charge, and the second conductive layer 25 is charged with a positive charge, and a negative charge as a latent image polar charge is accumulated in the electricity storage unit 29 formed at the interface between the recording photoconductive layer 22 and the charge transport layer 23. At the same time, the charge transport layer 23 functions as a so-called hole transport layer in which the mobility of the positive charge as the transport polarity charge having the opposite polarity is larger than the mobility of the negative charge as the latent image polarity charge. However, they may have opposite polarities, and when reversing the polarities as described above, the charge transporting layer that functions as a hole transporting layer may be used as an electron transporting layer. Only minor changes, such as changing to a charge transport layer that functions as a layer, are required.

For example, a photoconductive substance such as the above-mentioned amorphous selenium a-Se, lead (II) oxide, or lead (II) iodide can be similarly used as the recording photoconductive layer 22, and N can be used as the charge transport layer 23. -Trinitrofluorenylidene-aniline (TNFA) dielectrics, trinitrofluorenone (TNF) / polyester dispersions, asymmetric diphenoquinone derivatives are suitable, and the above-mentioned metal-free phthalocyanine and metal phthalocyanine are the same as the reading photoconductive layer 24. Can be used for

In the detector 20a, the power storage unit 29
Was formed at the interface between the recording photoconductive layer 22 and the charge transport layer 23, but the invention is not limited to this. For example, US Pat. No. 4,535,468.
As described in No. 5, the electricity storage unit may be formed by a trap layer that accumulates latent image polar charges as traps.

Any material may be used as the first conductive layer 21 as long as it is transparent to recording light. For example, when it is made transparent to visible light, it is known as a light-transmitting metal thin film. Film (SnO2), ITO (Indium Tin O
xide) or IDIXO (Idemitsu IndiumX-m) which is an amorphous light-transmissive metal oxide that is easy to etch
etal Oxide; Idemitsu Kosan Co., Ltd., etc.
It can be used with a thickness of about 200 nm, preferably 100 nm or more. In addition, aluminum Al, gold Au,
A pure metal such as molybdenum Mo or chromium Cr is used, for example, 20
By setting the thickness to be less than or equal to nm (preferably about 10 nm), it is possible to impart the transparency to visible light. Note that X-rays are used as the recording light, and the first conductive layer 21
When recording the image by irradiating the X-ray from the side,
Since the conductive layer 21 does not need to transmit visible light, the first conductive layer 21 is made of, for example, Al having a thickness of 100 nm.
A pure metal such as Au or Au can also be used.

The second conductive layer 25 includes a photocharge pair generating electrode 26 having a large number of linear electrodes 26a that are transparent to the reading light and a photocharge pair non-generating electrode having a large number of linear electrodes 27a that are shielded from the reading light. And 27. The linear electrode 26a of the photocharge pair generating electrode 26 and the linear electrode 27 of the photocharge pair non-generating electrode 27
They are arranged so that they are alternately arranged in parallel with a.

The photocharge pair generating electrode 26 and the photocharge pair non-generating electrode 27 are provided separately in the stacking direction of the layers, and the photocharge pair generating electrode 26 and the photocharge pair non-generating electrode 27 are further provided. An insulating layer 28 is provided between them.

The photocharge pair non-generating electrode 27 is an electric signal having a level corresponding to the amount of latent image charge accumulated in the electricity storage unit 29 formed at the substantially interface between the recording photoconductive layer 22 and the charge transport layer 23. Is a conductive member for outputting.

FIG. 2A shows a sectional view of the solid-state detector 20a. A part of the reading photoconductive layer 24 is interposed between the linear electrodes 26a of the photocharge pair generating electrode 26, and the photocharge pair generating electrode 26 and the photocharge pair non-generating electrode 27 are electrically connected by the insulating layer 28. Insulated. Further, on the lower surface and the upper surface of the photocharge pair non-generating electrode 27, the low reflectance layer 40a having a lower reflectance characteristic for the reading light than the photocharge pair non-generating electrode 27 is formed.
And 40b are provided.

By providing the low reflectance layer 40a on the lower surface of the photocharge pair non-generating electrode 27, the photocharge pair non-generating electrode 27 is formed.
The reading light incident from below, or the reading light reflected inside the solid-state detector 20a, emitted to the outside, reflected outside the solid-state detector 20a, and then incident on the solid-state detector 20a again is not generated by the photocharge pair non-generating electrode 27. Can be prevented from entering the reading photoconductive layer 24 above the photocharge pair non-generating electrode 27 by being reflected by the lower surface of the substrate 18 and again by the interface between the support 18 and the outside of the solid-state detector 20a. .

Further, by providing the low-reflectance layer 40b on the upper surface of the photocharge pair non-generating electrode 27, the lower surface of the photocharge pair generating electrode 26 which is incident from above the photocharge pair non-generating electrode 27 and for reading. The reflected light (reading light) reflected (scattered) at the interface between the photoconductive layer 24 and the insulating layer 28 is the photocharge pair non-generating electrode 2
It is possible to prevent diffused reflection on the upper surface of 7 and incident on the reading photoconductive layer 24 above the photocharge pair non-generating electrode 27 and further scattering in the detector 20a.

Of course, scattering reflection light (reading light) other than the above can be prevented by providing the low reflectance layers 40a and 40b.

The low reflectance layers 40a and 40b are not necessarily provided on both surfaces of the photocharge pair non-generating electrode 27, and may be provided on only one of them.

Further, as shown in FIG. 2B, when the insulating layer 28 is not provided between the photocharge pair generating electrode 26 and the photocharge pair non-generating electrode 27, the photocharge pair non-generating electrode 27 is not provided. The low reflectance layer 40a may be provided only on the lower surface of the.

Here, as a material of the electrode material forming each linear electrode 26a of the photocharge pair generating electrode 26, ITO (In
dium Tin Oxide), IDIXO (Idemitsu Indium X-me
talOxide; Idemitsu Kosan Co., Ltd., aluminum or molybdenum can be used. Further, as a material of the electrode material forming each linear electrode 27a of the photocharge pair non-generating electrode 27, aluminum, molybdenum, chromium or the like can be used.

In this detector 20a, the recording light guide is used.
Between the first conductive layer 21 and the power storage unit 29 with the electric layer 22 interposed therebetween.
Capacitor C_{* A}Are formed, the charge transport layer 23 and the read
The photoconductive layer 24 is sandwiched between the power storage unit 29 and the photocharge pair generating power.
Capacitor C between pole 26 (element 26a)_{* B}
Are formed, and the reading photoconductive layer 24 and the charge transport layer 23 are formed.
The storage unit 29 and the photocharge pair non-generating electrode 27 (element
Capacitor 27a) and a capacitor C_{* C}Is formed.
When recharging the charge during reading, each capacitor
C_{* A}, C_{* B}, C_{* C}Amount of positive charge distributed to
Q_{+ A}, Q_{+ B}, Q_{+ C}Is the total Q₊Of the latent image polar charge
Quantity Q₋The same as, the capacitance C of each capacitor_a, C_b, C _c
The amount is proportional to. This can be expressed as a table as shown below.
You can

Q ₋ = Q ₊ = Q _{+ a} + Q _{+ b} + Q _{+ c} Q _{+ a} = Q ₊ × C _a / (C _a + C _b + C
_c ) Q _{+ b} = Q ₊ × C _b / (C _a + C _b + C
_c ) Q _{+ c} = Q ₊ × C _c / (C _a + C _b + C
_c ) Then, the amount of signal charge that can be taken out from the detector 20a is the same as the sum (Q _{+ a} + Q _{+ c} ) of the amounts of positive charges Q _{+ a} and Q _{+ c} distributed to the capacitors C _{* a} and C _{* c} , and the capacitor C _{* The} positive charge distributed to _b cannot be taken out as a signal charge (for details, see JP-A-2000-284056).
(See the official gazette).

Considering the capacities of the capacitors C _{* b} and C _{* c formed} by the photocharge pair generating electrode 26 and the photocharge pair non-generating electrode 27, the capacitance ratio _Cb : _Cc is calculated as _follows : The width ratio Wb: Wc of 27a is obtained. On the other hand, the capacitance C _b of the capacitor C _a and the capacitor C _{* b} in the capacitor C _{* a} do not appear substantially greater influence provided photocharge to non generation electrode 27.

As a result, during charge rearrangement at the time of reading, the amount of positive charges Q _{+ b} distributed to the capacitor C _{* b} should be made relatively smaller than in the case where the photocharge pair non-generating electrode 27 is not provided. Therefore, the amount of signal charge that can be taken out from the detector 20a via the photocharge pair non-generating electrode 27 can be made relatively larger than that in the case where the photocharge pair non-generating electrode 27 is not provided.

Next, a second embodiment of the solid-state radiation detector according to the present invention will be described with reference to FIG. Figure 3
FIG. 4 is a diagram showing a schematic configuration of a second embodiment of the solid-state detector of the present invention, FIG. 3 (A) is a perspective view of the solid-state detector 20b, and FIG. 3 (B) is a Q arrow finger of the solid-state detector 20b. 3 is a cross-sectional view taken along the line XZ of FIG. 3C, and FIG.
FIG. In addition, in FIG. 3, the first shown in FIG.
The same elements as those of the detector 20a according to the embodiment of the present invention are designated by the same reference numerals, and the description thereof will be omitted unless particularly necessary.

Incidentally, the solid-state detector 20b of the present embodiment.
Is between the second conductive layer 25 and the support 18 of the solid-state detector 20a of the first embodiment.
A light-shielding film 31 that shields the reading light incident on the beam No. 7 is added.

Embodiments of the present invention will be described below with reference to the drawings.

This solid-state detector 20b generates a charge pair by receiving the irradiation of the first conductive layer 21 that is transparent to the recording light and the recording light that has passed through the first conductive layer 21 and becomes conductive. The recording photoconductive layer 22 which is present, acts substantially as an insulator against the latent image polar charge (for example, negative charge) in the charge pair, and has a transport polar charge (above-mentioned polarity opposite to the latent image polar charge). (For example, positive charge), the charge transport layer 23 acts substantially as a conductor, the reading photoconductive layer 24 that exhibits conductivity by generating a charge pair when irradiated with reading light, and a photocharge pair generation A second conductive layer 25 having an electrode 26 and a photocharge pair non-generating electrode 27, an insulating layer 30 having read light transparency, and a support 18 having read light transparency are arranged in this order. It will be. At the interface between the recording photoconductive layer 22 and the charge transport layer 23, a two-dimensionally distributed power storage unit 29 for accumulating the latent image polar charge carrying the image information generated in the recording photoconductive layer 22 is formed. It

FIG. 4 shows a sectional view of the solid-state detector 20b.
Each linear electrode 27a and linear electrode 26a on the support 18
And the linear electrode 27a, a portion having a low light transmission property is provided so that the irradiation intensity of the reading light on the linear electrode 27a is lower than the irradiation intensity of the reading light on the linear electrode 26a. Is provided.

The member of the light-shielding film 31 does not necessarily have an insulating property, and the light-shielding film 31 has a specific resistance of 2 × 10 ⁻⁶ or more (more preferably 1 × 10 6).
¹⁵ Ω · cm or less) can be used. For example, metal materials such as Al, Mo, and Cr can be used, and organic materials include MOS ₂ , WSi ₂ , and TiN.
Etc. can be used. It is more preferable to use a light-shielding film 31 having a specific resistance of 1 Ω · cm or more.

When at least a conductive member such as a metal material is used as the member of the light shielding film 31, the light shielding film 3 is used.
In order to avoid direct contact between the element 1 and the element 27a, an insulator is arranged between them. The detector 20b of the present embodiment is provided with an insulating layer 30 made of SiO ₂ or the like between the second conductive layer 25 and the support 18 as this insulator. The insulating layer 30 has a thickness of about 0.01 to 10 μm, more preferably about 0.1 μ to 1 μm, and most preferably 0.5 μm.
The degree is good.

On the lower surface of the light-shielding film 31, a low-reflectance layer 41a having a lower reflectance characteristic for reading light than the light-shielding film 31 is provided.
Is provided. The low-reflectance layer 41a is used as the light-shielding film 31.
By being provided on the lower surface of the light-shielding film 31, the reading light incident from below the light-shielding film 31 or reflected inside the solid-state detector 20b to be emitted to the outside, reflected outside the solid-state detector 20b, and incident to the solid-state detector 20b again. The reading light is reflected on the lower surface of the light shielding film 31, is further reflected again at the interface between the support 18 and the outside of the solid state detector 20b, and is incident on the reading photoconductive layer 24 above the photocharge pair non-generating electrode 27. Can be prevented.

Of course, scattering reflection light (reading light) other than the above can be prevented by providing the low reflectance layer 41a.

The low reflectance layer is not limited to being provided only on the lower surface of the light shielding film 31, but may be provided on both surfaces of the light shielding film 31 or only on the upper surface thereof.

Even when the light shielding film 31 is provided, a low reflectance layer may be provided on the photocharge pair non-generating electrode 27 as in the first embodiment.

Although the preferred embodiment of the solid-state detector according to the present invention has been described above, the present invention is not limited to the above-mentioned embodiment, and various modifications can be made without changing the gist of the invention. It is possible.

For example, the detector according to the above embodiment is
In either case, the recording photoconductive layer exhibits conductivity by irradiation with recording radiation, but the recording photoconductive layer of the detector according to the present invention is not necessarily limited to this. The photoconductive layer may be made conductive by irradiation with light emitted by excitation of recording radiation (see JP-A-2000-105297). In this case, the so-called X that converts the wavelength of the recording radiation on the surface of the first conductive layer into light in another wavelength range, such as blue light, is used.
It is preferable that a wavelength conversion layer called a line scintillator is laminated. As the wavelength conversion layer, it is preferable to use, for example, cesium iodide (CsI) or the like. Also, the first
The conductive layer is transparent to the light emitted from the wavelength conversion layer when excited by the recording radiation.

Further, in the detector according to the above-mentioned embodiment, the charge transport layer is provided between the recording photoconductive layer and the reading photoconductive layer, and the electricity storage unit is provided at the interface between the recording photoconductive layer and the charge transport layer. However, the charge transport layer may be replaced with a trap layer. When the trap layer is used, the latent image charge is captured by the trap layer, and the latent image charge is accumulated in the trap layer or at the interface between the trap layer and the recording photoconductive layer. Further, a microplate may be provided at the interface between the trap layer and the recording photoconductive layer for each pixel.

[Brief description of drawings]

FIG. 1 is a perspective view of a solid-state detector according to a first embodiment of the present invention (A), an XZ sectional view of a Q arrow finger portion (B), an XY sectional view of a P arrow finger portion (C).

FIG. 2 is a sectional view of the solid-state detector according to the first embodiment of the present invention.

FIG. 3 is a perspective view of a solid-state detector according to a second embodiment of the present invention (A), an XZ sectional view of a Q arrow finger portion (B), an XY sectional view of a P arrow finger portion (C).

FIG. 4 is a sectional view of a solid-state detector according to a second embodiment of the present invention.

[Explanation of symbols]

20a, b solid state detector 21 First conductive layer 22 Photoconductive layer for recording 23 Charge transport layer 24 Photoconductive layer for reading 25 Second conductive layer 26 Photocharge pair generating electrode 26a linear electrode 27 Photoelectric charge pair non-generating electrode 27a linear electrode 28 Insulation layer 29 power storage unit 40a, b low reflectance layer 41a low reflectance layer

Continued front page    F term (reference) 2G088 EE01 FF02 GG21 GG25 JJ05                       JJ09 JJ31 KK32 LL09 LL11                       LL12                 4M118 AA05 AA10 AB01 BA05 CA15                       CB05 CB14 DD01 GB18                 5C024 AX12 AX17 CX03 CX37 CY47                       DX04 GX07

Claims (2)

[Claims] 1. A first conductive layer having transmissivity for recording light, a recording photoconductive layer exhibiting photoconductivity by being irradiated with the recording light, and a recording conductive layer according to a light amount of the recording light. From a power storage unit that stores a certain amount of charge as latent image charge, a reading photoconductive layer that exhibits photoconductivity by being irradiated with reading light, and a large number of linear electrodes that are transparent to the reading light. And a photocharge pair non-generating electrode composed of a large number of linear electrodes, wherein the photocharge pair generating electrode linear electrodes and the photocharge pair non-generating electrode linear electrodes alternate with each other. And a second conductive layer disposed in this order, the photocharge pair non-generating electrode having a low reflectance characteristic with respect to the read light on the upper surface and / or the lower surface. Solid-state detector characterized by having a reflectance layer 2. A first conductive layer having transmissivity for recording light, a recording photoconductive layer exhibiting photoconductivity by being irradiated with the recording light, and a light-transmitting layer according to the amount of the recording light. From a power storage unit that stores a certain amount of charge as latent image charge, a reading photoconductive layer that exhibits photoconductivity by being irradiated with reading light, and a large number of linear electrodes that are transparent to the reading light. And a photocharge pair non-generating electrode composed of a large number of linear electrodes, wherein the photocharge pair generating electrode linear electrodes and the photocharge pair non-generating electrode linear electrodes alternate with each other. In the solid-state detector, the second conductive layer disposed on the light-shielding layer and a light-shielding film that shields the reading light with which the photocharge pair non-generating electrode is irradiated are stacked in this order. And / or a lower surface having a low reflectance characteristic with respect to the reading light. Solid state detector, characterized in that those having a morphism index layer.