JP3788740B2 - Active matrix substrate and electromagnetic wave detector - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention relates to an electromagnetic wave detector that detects radiation such as X-rays, electromagnetic waves such as visible light or infrared light, and an active matrix substrate.
[0002]
[Prior art]
  2. Description of the Related Art Conventionally, a semiconductor film that generates an electric charge (electron-hole pair) by sensing electromagnetic waves such as X-rays, that is, a semiconductor film having an electromagnetic wave conductivity and a semiconductor sensor composed of a pixel electrode (charge collecting electrode) and the like. 2. Description of the Related Art A two-dimensional electromagnetic wave detector is known that is arranged in a dimension and has a switching element on each pixel electrode. In this electromagnetic wave detector, the switching elements are sequentially turned on for each row, and the charges are read for each column.
[0003]
  For example, the document “DLLee, et al.,“ A New Digital Detector for Projection Radiografy ”, SPIE, 2432, pp. 237-249, 1995” describes a two-dimensional image detector corresponding to the electromagnetic wave detector. The specific structure and principle are described. The principle of this two-dimensional image detector will be described with reference to FIG.
[0004]
  A common single bias electrode 102 is formed on the upper layer of the semiconductor film 101 made of Se exhibiting electromagnetic wave conductivity, and a plurality of charge collecting electrodes 103 are formed on the lower layer. These charge collection electrodes 103 are connected to a charge storage capacitor (Cs) 104 and a TFT element (active element) 105, respectively. Note that dielectric layers 106 and 107 are provided as charge blocking layers between the semiconductor film 101 and the bias electrode 102 and between the semiconductor film 101 and the charge collection electrode 103, respectively, as necessary. Reference numeral 108 denotes an insulating substrate, and a high voltage power source 109 is connected to the bias electrode 102.
[0005]
  In such a two-dimensional image detector, when electromagnetic waves such as X-rays enter, charges (electron-hole pairs) are generated in the semiconductor film 101. At this time, the semiconductor film 101 and the charge storage capacitor 104 are electrically connected in series. Therefore, when a bias voltage is applied to the bias electrode 102, charges (electron-hole pairs) generated in the semiconductor film 101 move to the + electrode side and the − electrode side, respectively, and as a result, the charge storage capacitor 104 The charge is stored in
[0006]
  The charge stored in the charge storage capacitor 104 can be taken out by turning on the TFT element 105. As described above, in the two-dimensional image detector, the charge collection electrode 103, the charge storage capacitor 104, and the TFT element 105 are two-dimensionally arranged, and the charges are read out in a line-sequential manner, thereby detecting the two-dimensional electromagnetic waves to be detected. Information can be obtained.
[0007]
  In general, as the semiconductor film 101 having electromagnetic wave conductivity, Se, CdTe, CdZnTe, PbI are used.₂, HgI₂SiGe, Si, etc. are used. Among these, an Se film (particularly an amorphous a-Se film) has a low dark current (leakage current) characteristic and can be formed in a large area at a low temperature by a vacuum deposition method. It is widely used in electromagnetic wave detectors (especially X-ray detectors) having a structure in which a semiconductor film 101 is formed directly on 110 (see FIG. 9).
[0008]
[Problems to be solved by the invention]
  By the way, the active matrix substrate 110 used for the above-mentioned electromagnetic wave detector is usually made of a glass substrate as an insulating substrate 108, and a metal film (Al, Ta, etc.), a semiconductor film (a-Si, p-Si, etc.), By forming an insulating film (SiNx or SiOx) and patterning it into a predetermined shape, an element member such as an electric wiring or a TFT element 105 is formed.
[0009]
  However, for example, in the case of an electromagnetic wave detector in which an a-Se film is formed as the semiconductor film 101 on the active matrix substrate 110 in which the glass substrate is an insulating substrate 108, the thermal expansion coefficient of the glass substrate is 3 to 8 (× 10^-6/ ° C.) and the thermal expansion coefficient of Se film 30-50 (× 10^-6/ [Deg.] C.) has a difference of about an order of magnitude, so that the a-Se film easily peels off as the environmental temperature changes.
[0010]
  In addition, the a-Se film has a problem that it is easily peeled off by an external stress load that bends the insulating substrate 108. In particular, this peeling (film peeling) phenomenon is likely to occur from the outer end portion of the a-Se film. Therefore, when the electromagnetic wave detector has a large screen, it is between the a-Se film and the insulating substrate 108. This is particularly noticeable due to an increase in the difference in thermal expansion between the two and the warpage of the insulating substrate 108.
[0011]
  When the a-Se film is peeled off as described above, for example, charges generated in the a-Se film due to X-ray irradiation cannot reach the charge collection electrode 103 of the TFT element 105, and X-ray detection is performed. It becomes impossible. In addition, when the a-Se film is peeled off from the outer end portion, the peeling easily proceeds to the pixel array region, and damage is increased.
[0012]
  Therefore, an object of the active matrix substrate and the electromagnetic wave detector of the present invention is to prevent peeling of, for example, a semiconductor film formed on the active matrix substrate. Another object of the active matrix substrate and the electromagnetic wave detector of the present invention is to prevent, for example, peeling from the outer end side of a semiconductor film formed on the active matrix substrate.
[0013]
[Means for Solving the Problems]
  An electromagnetic wave detector according to the present invention is provided on an insulating substrate with a plurality of electrode wirings arranged in a grid, an active element arranged for each grid of these electrode wirings, and an upper layer of the electrode wiring and the active elements. And a plurality of pixel electrodes formed on the interlayer insulating layer. The interlayer insulating layer includes a pixel array region in which the electrode wirings are arrayed in a grid pattern, and the pixel array region. An at least part of the upper surface of the interlayer insulating layer disposed in the peripheral region is arranged so as to cover at least a part of the peripheral region that surrounds the concavo-convex portion including at least one of a concave portion and a convex portion. A semiconductor layer having electromagnetic wave conductivity so as to cover the pixel array region on the active matrix substrate and at least a part of the peripheral region. Made is, is characterized in that the semiconductor layer is laminated on said concavo-convex portion in the peripheral region.
[0014]
  According to the above configuration, the interlayer insulating layer of the active matrix substrate is disposed so as to cover the pixel array region and at least a part of the peripheral region, and at least a part of the upper surface of the interlayer insulating layer disposed in the peripheral region. In addition, a concavo-convex portion comprising at least one of a concave portion and a convex portion is formed. Such an active matrix substrate is used by further laminating other layers on the upper surface thereof. For example, when used as an electromagnetic wave detector, a semiconductor layer is laminated on the surface. In this case, when the semiconductor layer is laminated on the concavo-convex portion of the interlayer insulating layer, the semiconductor layer is joined in a state of being concavo-convexly fitted with the interlayer insulating layer in the peripheral region.
[0015]
  Therefore, the semiconductor layer is bonded to the interlayer insulating layer over a substantially wide area in the peripheral region, that is, the outer end portion of the semiconductor layer, and an anchor effect occurs in the bonded portion. As a result, when the semiconductor layer is stacked on the active matrix substrate, there is a large difference in thermal expansion coefficient between the semiconductor layer and the insulating substrate of the active matrix substrate, or an external force that bends the active matrix substrate. Even when added, peeling of the semiconductor layer from the active matrix substrate can be prevented.
[0016]
  In addition, when the semiconductor layer is peeled off from the active matrix substrate for the above-described reasons, the peeling usually occurs from the outer end portion of the semiconductor layer. Therefore, the semiconductor layer can be more reliably prevented from being peeled off by the configuration in which the uneven portion is formed in the peripheral region of the interlayer insulating layer of the active matrix substrate.
[0017]
  Eventually, according to the above configuration, it is possible to provide a highly reliable electromagnetic wave detector in which peeling of the semiconductor layer from the active matrix substrate hardly occurs.
[0018]
  aboveElectromagnetic wave detectorThe interlayer insulating layer may be made of a photosensitive organic material.
[0019]
  According to the above configuration, the interlayer insulating layer can be easily formed to a thickness of, for example, 1 to 5 μm, for example, by spin coating, and the interlayer insulating layer itself has photosensitivity. It is possible to easily form the uneven portion.
[0020]
  aboveElectromagnetic wave detectorIs a structure in which the surface of the concavo-convex portion is covered with an inorganic layer that provides higher bonding strength than the surface of the concavo-convex portion with respect to the semiconductor layer laminated on the active matrix substrate so as to be in contact with the concavo-convex portion. It is good.
[0021]
  According to the above configuration, since the interlayer insulating layer and the semiconductor layer laminated on the uneven portion of the interlayer insulating layer are not compatible with each other in the material, sufficient bonding strength cannot be obtained between the two in the uneven portion. Even in this case, as described above, the surface of the concavo-convex portion is covered with an inorganic layer that provides a higher bonding strength than the surface of the concavo-convex portion with respect to the semiconductor layer laminated thereon, A desired bonding strength can be obtained in the uneven portion.
[0022]
  aboveElectromagnetic wave detectorThe inorganic layer may be made of the same material as the pixel electrode.
[0023]
  According to said structure, the said inorganic layer can be formed simultaneously in the formation process of a pixel electrode. Therefore, while suppressing an increase in the number of processes, an inorganic layer is formed on the concavo-convex portion, that is, a decrease in bonding strength at the concavo-convex portion due to a mismatch of material compatibility between the interlayer insulating layer and the semiconductor layer is prevented, and a desired amount Bonding strength can be obtained.
[0024]
  aboveElectromagnetic wave detectorThe concavo-convex portion is formed in the interlayer insulating layer in a region in contact with the insulating substrate and has a structure penetrating the interlayer insulating layer, and between the interlayer insulating layer and the insulating substrate in the concavo-convex portion, The semiconductor layer stacked on the active matrix substrate so as to be in contact with the concavo-convex portion may have a structure in which an inorganic layer capable of obtaining higher bonding strength than the surface of the insulating substrate is formed.
[0025]
  According to said structure, even if it is a case where the glass substrate whose surface becomes a mirror surface is used as an insulating substrate, penetration of the uneven part of the semiconductor layer laminated | stacked on the uneven part of an interlayer insulation layer, for example The portion reaching the lower surface side of the interlayer insulating layer through the structure is in contact with the surface of the inorganic layer, not the surface of the glass substrate which is a mirror surface. In this case, since the inorganic layer has a higher bonding strength than the surface of the insulating substrate with respect to the semiconductor layer, the semiconductor layer can obtain a desired connection strength at the uneven portion.
[0026]
  aboveElectromagnetic wave detectorMay have a configuration in which the concavo-convex portion is formed at a position that does not overlap the electrode wiring in the stacking direction of the interlayer insulating layer with respect to the electrode wiring.
[0027]
  According to the above configuration, when a semiconductor layer, for example, is stacked on the active matrix substrate, the distance between the electrode wiring and the semiconductor layer can be reliably separated by the thickness of the interlayer insulating layer. Thereby, the electrostatic capacitance which generate | occur | produces between an electrode wiring and a semiconductor layer can be reduced, and the said unnecessary electrical coupling can be made small. As a result, for example, it is possible to suppress a situation where noise generated in the semiconductor layer is mixed into the electrode wiring and the S / N of the active matrix substrate is lowered.
[0028]
  The electromagnetic wave detector may be configured such that the thickness of the portion of the semiconductor layer on the uneven portion gradually decreases toward the outer side of the active matrix substrate.
[0029]
  According to said structure, peeling from the outer end part of the semiconductor layer with respect to an active matrix substrate can be prevented further more reliably.
[0030]
  The electromagnetic wave detector according to the present invention includes a plurality of electrode wirings arranged in a grid and active elements arranged for each grid of these electrode wiringsAnd an interlayer insulating layer and a plurality of pixel electrodes are sequentially stacked.An active matrix substrate having a pixel array region and a peripheral region surrounding the pixel array region, and electromagnetic wave conductivity formed on the surface of the active matrix substrate so as to cover the pixel array region and at least a part of the peripheral region In an electromagnetic wave detector comprising a semiconductor layer havingThe interlayer insulating layer is formed in at least a part of the pixel array region and the peripheral region,The peripheral region of the active matrix substrate;In the interlayer insulating layerIn contact with the semiconductor layerIn the areaIn addition, an uneven portion comprising at least one of a concave portion and a convex portion is formed.
[0031]
  According to the above configuration, the peripheral region of the active matrix substrateIn the interlayer insulating layerIn contact with the semiconductor layerIn the areaSince the concavo-convex part consisting of at least one of the concave part and the convex part is formed, the semiconductor layerSaidIn the surrounding areaConcaveJoined in a convex fit.
[0032]
  Therefore, the semiconductor layer is bonded to the active matrix substrate over a substantially wide area in the peripheral region of the active matrix substrate, that is, the outer end portion of the semiconductor layer, and an anchor effect is generated in the bonded portion. As a result, even when there is a large difference in thermal expansion coefficient between the semiconductor layer and the active matrix substrate, or when an external force that bends the active matrix substrate is applied, the semiconductor layer from the active matrix substrate Peeling can be prevented.
[0033]
  In addition, when the semiconductor layer is peeled off from the active matrix substrate for the above-described reasons, the peeling usually occurs from the outer end portion of the semiconductor layer. Therefore, the semiconductor layer can be more reliably prevented from being peeled off by the configuration in which the uneven portion is formed in the peripheral region of the active matrix substrate.
[0034]
  An electromagnetic wave detector according to the present invention includes a plurality of electrode wirings arranged in a grid pattern on an insulating substrate, an active element arranged for each grid of the electrode wirings, an interlayer insulating layer, a plurality of pixel electrodes, and electromagnetic wave conduction. In the electromagnetic wave detector in which the semiconductor layers having the properties are sequentially laminated, an uneven portion including at least one of a concave portion and a convex portion is formed in at least a part of the region in contact with the semiconductor layer in the interlayer insulating layer. It is characterized by being.
[0035]
  According to the above configuration, since the concavo-convex portion including at least one of the concave portion and the convex portion is formed in at least a part of the region in contact with the semiconductor layer in the interlayer insulating layer, the semiconductor layer is the interlayer in the rugged portion. Bonded with the insulating layer in a concavo-convex manner. In this case, the uneven portion is provided, for example, at a position between adjacent pixels in the interlayer insulating layer.
[0036]
  Therefore, the semiconductor layer is bonded to the interlayer insulating layer over a substantially wide area in the concavo-convex portion, and an anchor effect occurs at the bonded portion. As a result, even when there is a large difference in thermal expansion coefficient between the semiconductor layer and the insulating substrate, or when an external force that bends the electromagnetic wave detector is applied, the semiconductor layer is peeled off from the insulating substrate. Can be prevented.
[0037]
  Said electromagnetic wave detector is good also as a structure by which the surface of the said uneven | corrugated | grooved part is covered with the inorganic layer from which the joint strength higher than the surface of an uneven | corrugated | grooved part with respect to the said semiconductor layer is obtained.
[0038]
  According to the above configuration, since the interlayer insulating layer and the semiconductor layer laminated on the uneven portion of the interlayer insulating layer are not compatible with each other in the material, sufficient bonding strength cannot be obtained between the two in the uneven portion. Even in this case, as described above, the surface of the concavo-convex portion is covered with an inorganic layer that provides a higher bonding strength than the surface of the concavo-convex portion with respect to the semiconductor layer laminated thereon, A desired bonding strength can be obtained in the uneven portion.
[0039]
  In the electromagnetic wave detector, the surface of the concavo-convex portion is covered with an inorganic layer capable of obtaining higher bonding strength than the surface of the concavo-convex portion with respect to the semiconductor layer, and the inorganic layer is made of the same material as the pixel electrode. It is good also as composition which consists of.
[0040]
  According to said structure, the said inorganic layer can be formed simultaneously in the formation process of a pixel electrode. Therefore, while suppressing an increase in the number of processes, an inorganic layer is formed on the concavo-convex portion, that is, a decrease in the bonding strength at the concavo-convex portion due to a mismatch in material compatibility between the interlayer insulating layer and the semiconductor layer can be prevented. Bonding strength can be obtained.
[0041]
  In the electromagnetic wave detector, the uneven portion is formed in the interlayer insulating layer in a region in contact with the insulating substrate and has a structure penetrating the interlayer insulating layer, and the interlayer insulating layer and the insulating substrate in the uneven portion A structure in which an inorganic layer capable of obtaining a higher bonding strength than the surface of the insulating substrate with respect to the semiconductor layer may be formed.
[0042]
  According to said structure, even if it is a case where the glass substrate whose surface becomes a mirror surface is used as an insulating substrate, penetration of the uneven part of the semiconductor layer laminated | stacked on the uneven part of an interlayer insulation layer, for example The portion reaching the lower surface side of the interlayer insulating layer through the structure is in contact with the surface of the inorganic layer, not the surface of the glass substrate which is a mirror surface. In this case, since the inorganic layer has a higher bonding strength than the surface of the insulating substrate with respect to the semiconductor layer, the semiconductor layer can obtain a desired connection strength at the uneven portion.
[0043]
  An active matrix substrate of the present invention is provided on an insulating substrate with a plurality of electrode wirings arranged in a grid pattern, an active element arranged for each grid of these electrode wirings, and an upper layer of the electrode wirings and the active elements. And a plurality of pixel electrodes formed on the interlayer insulating layer. The interlayer insulating layer includes a pixel array region in which the electrode wirings are arrayed in a grid pattern, and the pixel array region. An at least part of the upper surface of the interlayer insulating layer disposed in the peripheral region is arranged so as to cover at least a part of the peripheral region that surrounds the concavo-convex portion including at least one of a concave portion and a convex portion. A bonding layer having a coefficient of thermal expansion different from that of the insulating substrate is formed so as to cover the pixel array region and at least a part of the peripheral region, and the bonding layer is formed in the peripheral region in the peripheral region. It is characterized in that it is laminated on the convex portion.
[0044]
DETAILED DESCRIPTION OF THE INVENTION
  [Embodiment 1]
  An embodiment of the present invention will be described below with reference to FIGS. In the electromagnetic wave detector and the active matrix substrate, the pixel arrangement area is an area in which electrode wirings are arranged in a grid pattern, and this area is an active area in which active elements and pixel electrodes are arranged in a two-dimensional manner. It has become. In particular, the electromagnetic wave detector corresponds to the imaging region.
[0045]
  As shown in FIGS. 2A and 2B, the electromagnetic wave detector according to the present embodiment includes an active matrix substrate 11, a semiconductor film (semiconductor layer) 12, and a bias electrode 13 as main components. The active matrix substrate 11 has an active matrix array in the pixel array region 14. The semiconductor film 12 generates a charge in response to the electromagnetic wave to be detected. The bias electrode 13 is for applying a bias voltage to the semiconductor film 12.
[0046]
  As shown in FIG. 3, the active matrix substrate 11 has an insulating substrate 21 made of glass or ceramics, and the active matrix array is formed on the insulating substrate 21. This active matrix array includes, for example, a TFT element (active element) 22 using a-Si or p-Si, a charge storage capacitor (Cs) 23, a charge collection electrode (pixel electrode) 24, and a gate electrode forming a bus line. 25, data electrodes 29, and the like are arranged in an XY matrix. In addition to the TFT element 22, the active element may be, for example, an MIM element or a diode element.
[0047]
  In the XY matrix, the size of one pixel corresponding to the unit cell is 0.1 × 0.1 mm.²~ 0.3 × 0.3mm²In general, one pixel is arranged in a matrix of about 500 × 500 to 3000 × 3000 pixels.
[0048]
  FIG. 3 is a longitudinal sectional view showing the configuration of the electromagnetic wave detector per pixel. The configuration is as follows in more detail.
In the active matrix substrate 11, a gate electrode 25, a charge storage capacitor (Cs) electrode 26, a charge storage capacitor 23, a gate insulating film 27, a connection electrode (drain electrode) 28, a data electrode are formed on an insulating substrate 21 made of, for example, a glass substrate. A (source electrode) 29, a TFT element 22, an insulating protective film 30, an interlayer insulating film (interlayer insulating layer) 31, a charge collection electrode (pixel electrode) 24, and the like are formed. The TFT element 22 has a channel layer 32 and a contact layer 33. A contact hole 34 is formed in the interlayer insulating film 31, and the charge collection electrode 24 is connected to the connection electrode 28 through the contact hole 34. In the electromagnetic wave detector, the semiconductor film 12 and the bias electrode 13 are formed on such an active matrix substrate 11.
[0049]
  Said electromagnetic wave detector can be manufactured as follows.
For example, a non-alkali glass substrate (for example, # 1737 manufactured by Corning) can be used as the glass substrate as the insulating substrate 21. Then, a gate electrode 25 and a charge storage capacitor electrode 26 made of a metal film such as Ta or Al are formed on the glass substrate 1. These are formed by forming the metal film on a glass substrate to a thickness of about 3000 mm by sputtering deposition and then patterning it into a desired shape.
[0050]
  Next, a gate insulating film 27 made of SiNx, SiOx, or the like is formed on the entire upper surface of the glass substrate so as to cover the gate electrode 25 and the charge storage capacitor electrode 26 by a CVD method to a thickness of about 3500 mm. The gate insulating film 27 also functions as a dielectric in the charge storage capacitor 23. The gate insulating film 27 is not limited to SiNx or SiOx, and an anodic oxide film obtained by anodizing the gate electrode 25 and the charge storage capacitor electrode 26 can be used in combination.
[0051]
  Next, a channel layer (i layer) 32 serving as a channel portion of the TFT element (TFT) 22, a data electrode 29, a connection electrode (drain electrode) 28, and a gate electrode 25 are disposed above the gate electrode 25. Contact layer (n⁺Layer) 33 is formed. These are made of a-Si, and can be formed by forming a film to a thickness of about 1000 mm and about 400 mm by a CVD method, and then patterning the film into a desired shape.
[0052]
  Next, the contact layer (n⁺A data electrode 29 and a connection electrode (drain electrode) 28 are formed on the (layer) 33. The connection electrode 28 is also an upper layer side electrode constituting the charge storage capacitor 23. Similar to the gate insulating film 27 and the charge storage capacitor electrode 26, the data electrode 29 and the connection electrode 28 are formed into a desired shape after a metal film such as Ta or Al is formed by sputtering deposition to a thickness of about 3000 mm. It is formed by patterning.
[0053]
  Next, an insulating protective film 30 is formed so as to cover almost the entire surface of the insulating substrate (glass substrate) 21 on which the TFT element 22 and the charge storage capacitor 23 are formed. The insulating protective film 30 is formed by depositing SiNx to a thickness of about 3000 mm by CVD. Note that SiNx is removed in a portion on the connection electrode 28 where the contact hole 34 is formed.
[0054]
  Next, an interlayer insulating film 31 is formed so as to cover almost the entire surface of the insulating protective film 30. The interlayer insulating film 31 is formed by depositing a photosensitive acrylic resin to a thickness of about 3 μm using a coating device such as a spinner. In addition, polyimide resin or the like can be used as the organic material having photosensitivity.
[0055]
  Thereafter, using a photomask having a predetermined light-shielding pattern, the interlayer insulating film 31 is subjected to exposure / development processing (photolithography) to form a contact hole 34 for each pixel. In the contact hole 34, a hole penetrating the interlayer insulating film 31 in the vertical direction is formed, and the lower connection electrode (drain electrode) 28 is exposed.
[0056]
  Next, a conductive film is patterned as the charge collecting electrode 24 on the interlayer insulating film 31 in which the contact hole 34 is formed. The charge collection electrode 24 is electrically connected to the connection electrode 28 of the TFT element 22 through the contact hole 34.
[0057]
  Examples of the charge collection electrode 24 include an ITO film (indium tin oxide film) having a thickness of 0.1 to 0.2 μm, an IZO film (indium zinc oxide film), an Al film, and an Al alloy film (for example, Al—Nd, Al— Zr alloy or the like), a laminated film of Al and another conductive film (for example, Al / Mo, Al / Ti, or the like) can be used. In the present application, the Al film, the Al alloy film, and the laminated film of Al and another conductive film are collectively referred to as a “conductive film containing Al as a main component”.
[0058]
  Next, an electromagnetic conductive semiconductor film 12 made of a-Se is formed on the active matrix substrate 11 formed as described above so as to cover the entire pixel array region 14. In consideration of the X-ray absorption efficiency, the semiconductor film 12 is formed by a vacuum evaporation method so that the film thickness is about 0.5 to 1.5 mm, preferably 1 mm. Note that, in addition to a-Se, CdTe, CdZnTe, PbI can be used for the semiconductor film having electromagnetic conductivity.₂, HgI₂SiGe, Si, or the like can be used. However, in the case of an electromagnetic wave detector having a structure in which the semiconductor film 12 is directly formed on the active matrix substrate 11 on which the active matrix array is formed, an amorphous Se film capable of forming a large area at a low temperature by a vacuum deposition method. (A-Se film) is optimal.
[0059]
  Then, a bias electrode 13 made of Au, Al or the like is formed on almost the entire surface of the semiconductor film 12 with a thickness of about 2000 mm by a vacuum deposition method, so that FIGS. 2 (a), 2 (b) and FIG. The electromagnetic wave detector shown is obtained. A bias voltage is applied to the uppermost bias electrode 13 from an external high-voltage power supply (not shown).
[0060]
  Next, a configuration characterized by the electromagnetic wave detector of the present embodiment will be described with reference to FIG. FIG. 1 is a cross-sectional view taken along line AA in FIG. However, in FIG. 1, for convenience, the TFT elements 22 and the electrode wirings constituting the active matrix substrate 11 are omitted, and only the interlayer insulating film 31 and the charge collecting electrode (pixel electrode) 24 are illustrated.
[0061]
  As shown in FIG. 1, the active matrix substrate 11 generally includes a pixel array region 14 (active region, matrix region) in which electrode wirings are arranged in a lattice pattern, and other regions, that is, a peripheral portion of the pixel array region 14. And the peripheral region 15 located in
[0062]
  In the active matrix substrate 11, the interlayer insulating film 31 is formed in a wide area from the pixel array region 14 to a part of the peripheral region 15. The interlayer insulating film 31 in the peripheral region 15 is provided with a concavo-convex portion 17 composed of at least one of a concave portion and a convex portion. The concavo-convex portion 17 functions as a bonding enhancing portion, and is not limited to the entire region of the interlayer insulating film 31 in the peripheral region 15 but may be formed in at least a part of the region. In the electromagnetic wave detector, the semiconductor film 12 is formed from the pixel array region 14 to the region where the uneven portion 17 is formed in the peripheral region 15. That is, in the peripheral region 15, the semiconductor film 12 is formed on the interlayer insulating film 31 and is joined in a state of being engaged with the concavo-convex portion 17.
[0063]
  As said uneven | corrugated | grooved part 17, various dot patterns, stripe patterns, or wavy line patterns can be formed at an arbitrary density. Examples of the dot pattern include those shown in FIGS. 4A and 4B, and examples of the stripe pattern include those shown in FIG. 4C. Each of the patterns shown in FIGS. 4A to 4C may be a concave portion or a convex portion.
[0064]
  In each pattern such as the dot pattern and the stripe pattern, for example, the depth or height can be about 3 μm and the width (diameter) can be about 5 to 10 μm.
[0065]
  In addition, although the uneven | corrugated | grooved part 17 shall consist of at least one of a recessed part and a convex part, it forms a recessed part or a convex part, such as a concave thing, a convex thing, a groove | channel, a hole, a satin, etc. Various structures for are included.
[0066]
  For example, when the concave and convex portion 17 is formed of a concave portion, it can be formed at the same time when the contact hole 34 is formed in the interlayer insulating film 31. In this case, it can be formed easily without adding a new process.
[0067]
  When the interlayer insulating film 31 is made of an acrylic resin, the insulating substrate 21 is made of a glass substrate, and the interlayer insulating film 31 is directly formed on the insulating substrate 21 in the peripheral region 15, the surface of the glass substrate is Since it is extremely mirror-finished, the insulating substrate 21 andInterlayer insulating film 31And the bonding strength is reduced. In this case, in the peripheral region 15 of the active matrix substrate 11, similarly to the pixel array region 14, SiNx and Si0 are formed below the interlayer insulating film 31.₂It is preferable to arrange an inorganic thin film (inorganic layer) made of, for example. Specifically, when the gate insulating film 27 or the insulating protective film 30 shown in FIG. 3 is formed, the film is formed on the insulating substrate 21 in the peripheral region 15 at a position where the interlayer insulating film 31 exists (the interlayer insulating film 31 It is good to form it continuously to the lower position.
[0068]
  In the above configuration, when an electromagnetic wave such as an X-ray is incident on the electromagnetic wave detector, an electric charge (electron-hole pair) is generated in the semiconductor film 12. At this time, the semiconductor film 12 and the charge storage capacitor 23 are electrically connected in series. Therefore, when a bias voltage is applied to the bias electrode 13, charges (electron-hole pairs) generated in the semiconductor film 12 move to the + electrode side and the -electrode side, respectively. As a result, charges are stored in the charge storage capacitor 23.
[0069]
  The charge stored in the charge storage capacitor 23 can be taken out to an external amplifier circuit (not shown) via the data electrode 29 by turning on the TFT element 22. At this time, since the charge collection electrode 24, the charge storage capacitor 23, and the TFT element 22 are arranged in an XY matrix as described above, by driving the TFT element 22 line-sequentially to read out charges, It becomes possible to obtain two-dimensional information of the electromagnetic wave to be detected.
[0070]
  Further, the active matrix substrate 11 has the concavo-convex portion 17 in the interlayer insulating film 31 in the peripheral region 15 as described above. Therefore, the electromagnetic wave detector formed by sequentially forming the semiconductor film 12 and the bias electrode 13 on the active matrix substrate 11, that is, the semiconductor film 12 is formed on the uneven portion 17 of the interlayer insulating film 31 in the peripheral region 15. In the electromagnetic wave detector arranged, the bonding area between the semiconductor film 12 and the interlayer insulating film 31 is increased and the semiconductor film 12 is An anchor effect occurs by being in a fitting state. Therefore, the bonding strength of the semiconductor film 12 to the active matrix substrate 11 is improved. As a result, when the thermal expansion coefficients of the semiconductor film 12 and the insulating substrate 21 are significantly different, the interlayer insulating film 31 due to the difference in thermal expansion amount between them, that is, the peeling of the semiconductor film 12 from the insulating substrate 21 or due to external force The semiconductor film 12 can be prevented from peeling off from the insulating substrate 21 due to deformation (warpage) of the electromagnetic wave detector or the like.
[0071]
  That is, for example, in the case of an electromagnetic wave detector in which an a-Se film is formed as the semiconductor film 12 on the active matrix substrate 11 using the glass substrate as the insulating substrate 21, the thermal expansion coefficient of the glass substrate is 3 to 8 (× 10^-6/ ° C.) and the coefficient of thermal expansion of the a-Se film of 30 to 50 (× 10^-6/ [Deg.] C.) has a difference of about an order of magnitude, and the a-Se film easily peeled off as the environmental temperature changed. Further, there has been a problem that the a-Se film is easily peeled off even by a slight external stress load that bends the insulating substrate 21.
[0072]
  Therefore, when the uneven portion 17 is formed in the interlayer insulating film 31 as described above and the semiconductor film 12 is formed on the uneven portion 17, the bonding area between the semiconductor film 12 and the interlayer insulating film 31 is increased. Due to the increase and the anchor effect by the concavo-convex portion 17, peeling of the semiconductor film 12 from the insulating substrate 21 can be prevented.
[0073]
  Further, the peeling of the semiconductor film 12 from the insulating substrate 21 tends to occur from the outer end portion of the semiconductor film 12. In order to deal with this problem, in the present embodiment, since the uneven portion 17 is formed in the interlayer insulating film 31 in the peripheral region 15 of the active matrix substrate 11, the peeling of the semiconductor film 12 particularly from the peripheral portion is appropriately prevented. It can be done.
[0074]
  Further, as shown in FIG. 1, the portion of the semiconductor film 12 on the concavo-convex portion 17 is formed such that the thickness gradually decreases toward the outer side of the active matrix substrate 11. Specifically, for example, it has a shape that has an inclination such that the thickness gradually decreases. Therefore, peeling of the semiconductor film 12 from the peripheral portion can be more appropriately prevented.
[0075]
  [Embodiment 2]
  Another embodiment of the present invention will be described below with reference to FIG.
The electromagnetic wave detector of the present embodiment has a configuration shown in FIG. In this electromagnetic wave detector, an uneven portion 17 is formed in the interlayer insulating film 31 in the peripheral region 15 of the active matrix substrate 11 in the same manner as the electromagnetic wave detector, and an inorganic film (inorganic layer) is formed on the uneven portion 17. 41 is formed. Other configurations are the same as those of the electromagnetic wave detector.
[0076]
  Although various thin films can be used for the inorganic film 41, the same material as the charge collection electrode (pixel electrode) 24 is used in order to suppress an increase in the manufacturing process of the electromagnetic wave detector (active matrix substrate 11). It is preferable to use it. Specifically, an ITO film (indium tin oxide film), an IZO film (indium zinc oxide film), an Al film, an Al alloy film (eg, Al—Nd, Al—Zr alloy, etc.), Al and another conductive film A laminated film (for example, Al / Mo, Al / Ti, etc.) or the like. In this case, the inorganic film 41 may be formed in the peripheral region 15 at the same time when the charge collection electrode 24 is patterned.
[0077]
  The inorganic film 41 has the following functions.
First, it functions as a connection strength promoting film between the interlayer insulating film 31 and the semiconductor film 12. That is, the interlayer insulating film 31 and the semiconductor film 12 formed on the interlayer insulating film 31 are not compatible with each other. Therefore, even if the physical uneven portion 17 is formed on the interlayer insulating film 31, When the bonding strength between the two is not sufficiently improved, the desired bonding strength can be obtained by arranging the inorganic film 41 between the two as described above. The inorganic film 41 used in this case has a bonding strength higher than that of the uneven portion 17, that is, the surface of the interlayer insulating film 31, with respect to the semiconductor film 12.
[0078]
  Second, it functions as a protective film that protects the concavo-convex portion 17 from a chemical solution in the manufacturing process. That is, after forming the concavo-convex portion 17 and the contact hole 34 in the interlayer insulating film 31, the patterning process of the charge collection electrode (pixel electrode) 24 is performed by a known photolithography technique or etching technique using a photoresist. At that time, the interlayer insulating film 31 is exposed to a photoresist stripping solution (chemical solution). At this time, when the interlayer insulating film 31 is formed of an acrylic resin, the interlayer insulating film 31 has the concavo-convex portion 17, and therefore, compared with a flat structure that does not have the concavo-convex portion 17. As such, it may be easily damaged by the chemical solution, and the pattern of the concavo-convex portion 17 may collapse. Therefore, if the concavo-convex portion 17 is covered with the inorganic film 41, the concavo-convex portion 17 is not exposed to the chemical solution in the photoresist peeling process, and the concavo-convex portion 17 can maintain a good shape. .
[0079]
  [Embodiment 3]
  Still another embodiment of the present invention will be described below with reference to FIGS. The electromagnetic wave detector according to the present embodiment takes into account the preferred arrangement of the concavo-convex portions 17 in the configuration having the concavo-convex portions 17 in the interlayer insulating film 31 in the peripheral region 15 of the active matrix substrate 11.
[0080]
  In the electromagnetic wave detector of the present embodiment, the concavo-convex portion 17 is arranged as shown in FIG. This figure is a plan view of the vicinity of the peripheral region 15 in the active matrix substrate 11 of the electromagnetic wave detector, and shows a case where the concavo-convex portion 17 is formed of a concave portion. In addition, this uneven | corrugated | grooved part 17 may consist of a convex part, and as above-mentioned, may consist of a groove part, another concave or convex pattern.
[0081]
  As shown in FIG. 6, the active matrix substrate 11 of the electromagnetic wave detector has a large number of connection terminals 51 arranged in parallel at the edge thereof, and these connection terminals 51 have lead wires formed in the peripheral region 15. The electrode wiring 53 formed in a matrix in the pixel array region 14 is connected through 52. Note that the lead-out wiring 52 is also an electrode wiring, but here, the lead-out wiring 52 is used to distinguish it from the electrode wiring 53 formed in the pixel array region 14.
[0082]
  The uneven portion 17 is formed between the lead wires 52 so as not to overlap the lead wires 52. Therefore, the interlayer insulating film 31 exists on the lead wiring (electrode wiring) 52. As a result, the electromagnetic wave detector according to the present embodiment can suppress a situation in which noise generated in the semiconductor film 12 is superimposed on the electrode wiring 53, that is, the connection terminal 51.
[0083]
  That is, in general, some charge is generated in the semiconductor film 12 by X-ray irradiation or thermal excitation, and an unnecessary potential caused by the charge may be superimposed on the lower extraction wiring 52 as noise. Therefore, if the uneven portion 17 is formed so as not to overlap with the lead wiring 52 as described above, the distance between the lead wiring 52 and the semiconductor film 12 can be reliably separated by the thickness of the interlayer insulating film 31 (for example, 3 μm). it can. Thereby, the electrostatic capacitance generated between the lead-out wiring 52 and the semiconductor film 12 can be reduced, and the electrical coupling between them can be reduced. As a result, it is possible to suppress a situation in which noise is mixed into the detection signal of the electromagnetic wave detector and the S / N is lowered.
[0084]
  Note that the configuration of the active matrix substrate 11 described above can be applied not only to the electromagnetic wave detector but also to a liquid crystal display device 61 as shown in FIG. 7, for example. In the liquid crystal display device 61, a liquid crystal layer 63 is provided between the active matrix substrate 11 and the counter substrate 62, and the liquid crystal layer 63 is sealed between the two by a sealing material 64.
[0085]
  The sealing material 64 is made of a thermosetting resin, an ultraviolet curable resin, or the like, and is provided on the uneven portion 17 formed in the peripheral region 15 of the active matrix substrate 11. That is, the end of the sealing material 64 on the active matrix substrate 11 side is joined to the active matrix substrate 11 in a state of being engaged with the concavo-convex portion 17. With such a configuration, even when a load that peels off the active matrix substrate 11 and the sealing material 64, such as a bending load, is applied to the liquid crystal display device 61, both of them are easily pulled. It is not peeled off. Thereby, the reliability of the liquid crystal display device 61 can be improved.
[0086]
  Moreover, the electromagnetic wave detector of the above embodiment can be applied not only to a detector of radiation such as X-rays but also to detectors for various electromagnetic waves such as visible light and infrared light. Further, the structure of the active matrix substrate 11 and the material of the semiconductor film 12 are not limited to those shown in the above embodiment, and various other configurations and various materials can be used as appropriate.
[0087]
  Further, in the above embodiment, it is assumed that the uneven portion 17 is formed in the interlayer insulating film 31 in the peripheral region 15 of the active matrix substrate 11, so that a high peeling prevention function for the semiconductor film 12 can be exhibited. It is like that. However, the concavo-convex portion 17 is not necessarily formed in the peripheral region 15. For example, as shown in FIG. 8, the concavo-convex portion 17 is formed in the interlayer insulating film 31 between the pixels 55 in the pixel array region 14. Also good. Even in this case, it is possible to obtain a high peeling prevention function for the semiconductor film 12 as compared with the case where the uneven portion 17 is not provided.
[0088]
  Moreover, in the above embodiment, it is set as the structure which provided the uneven | corrugated | grooved part 17 with respect to the active matrix substrate 11 contained in an electromagnetic wave detector. However, the configuration provided with the concavo-convex portion 17 is not limited to this, and can also be applied to the active matrix substrate 11 as a product. In other words, the active matrix substrate 11 in this case is a product or film that assumes that a film (layer) whose thermal expansion coefficient is significantly different from that of the insulating substrate 21, for example, the semiconductor film 12 is formed on the upper surface. The product is distributed as a product that is easily or easily deformed and easily causes peeling of a film (layer) formed thereon.
[0089]
【The invention's effect】
  As described above, according to the electromagnetic wave detector and the active matrix substrate of the present invention, it is possible to provide a highly reliable electromagnetic wave detector and an active matrix substrate that hardly cause separation of the bonding layer.
[Brief description of the drawings]
FIG. 1 shows a configuration of an electromagnetic wave detector according to an embodiment of the present invention, and is a cross-sectional view taken along line AA in FIG.
FIG. 2A is a plan view showing an electromagnetic wave detector according to an embodiment of the present invention, and FIG. 2B is a schematic longitudinal sectional view of the electromagnetic wave detector.
3 is a longitudinal sectional view showing an enlarged view of one pixel portion in the electromagnetic wave detector shown in FIG. 2 (a). FIG.
4A is a plan view showing an example of a dot pattern that becomes the uneven portion shown in FIG. 1, and FIG. 4B is a plan view showing an example of another dot pattern that becomes the uneven portion; FIG. 4C is a plan view showing an example of a stripe pattern that becomes the uneven portion.
FIG. 5 is a longitudinal sectional view showing a configuration of an electromagnetic wave detector according to another embodiment of the present invention and corresponding to the portion shown in FIG. 1 of the electromagnetic wave detector.
FIG. 6 is a plan view showing a configuration of an electromagnetic wave detector according to still another embodiment of the present invention and in the vicinity of a peripheral region of an active matrix substrate on which uneven portions are formed.
FIG. 7 is a schematic longitudinal sectional view of a liquid crystal display device showing an example in which the active matrix substrate shown in the embodiment of the present invention is applied to a liquid crystal display device.
FIG. 8 shows a configuration of an electromagnetic wave detector according to still another embodiment of the present invention, and is a plan view of a main part in a pixel array region of an active matrix substrate on which uneven portions are formed.
FIG. 9 is a longitudinal sectional view for explaining the operation principle of a conventional electromagnetic wave detector.
[Explanation of symbols]
  11 Active matrix substrate
  12 Semiconductor film (semiconductor layer)
  13 Bias electrode
  14 pixel array area
  15 Peripheral area
  17 Concavity and convexity
  21 Insulating substrate
  22 TFT elements
  23 Charge storage capacity
  24 Charge collection electrode (pixel electrode)
  28 Connecting electrodes
  31 Interlayer insulation film (interlayer insulation layer)
  34 Contact hole
  41 Inorganic film (inorganic layer)
  51 Connection terminal
  52 Lead wiring

Claims (13)

On an insulating substrate,
A plurality of electrode wires arranged in a lattice pattern;
Active elements arranged for each grid of these electrode wirings,
An interlayer insulating layer provided in an upper layer of the electrode wiring and the active element;
A plurality of pixel electrodes formed on the interlayer insulating layer;
The interlayer insulating layer is disposed so as to cover a pixel array region in which the electrode wirings are arrayed in a lattice pattern and at least a part of a peripheral region surrounding the pixel array region, and is disposed in the peripheral region At least a part of the upper surface of the interlayer insulating layer includes an active matrix substrate in which a concavo-convex portion including at least one of a concave portion and a convex portion is formed,
A semiconductor layer having electromagnetic conductivity is formed so as to cover the pixel array region on the active matrix substrate and at least a part of the peripheral region, and the semiconductor layer is laminated on the uneven portion in the peripheral region. An electromagnetic wave detector. The electromagnetic wave detector according to claim 1, wherein the interlayer insulating layer is made of a photosensitive organic material. The surface of the concavo-convex portion is covered with an inorganic layer capable of obtaining a higher bonding strength than the surface of the concavo-convex portion with respect to the semiconductor layer stacked on the active matrix substrate so as to be in contact with the concavo-convex portion. The electromagnetic wave detector according to claim 1 or 2. The electromagnetic wave detector according to claim 3, wherein the inorganic layer is made of the same material as the pixel electrode. The concavo-convex portion is formed in the interlayer insulating layer in a region in contact with the insulating substrate and has a structure penetrating the interlayer insulating layer, and the concavo-convex portion is provided between the interlayer insulating layer and the insulating substrate in the concavo-convex portion. 4. The electromagnetic wave according to claim 3, wherein an inorganic layer capable of obtaining a bonding strength higher than a surface of the insulating substrate is formed on a semiconductor layer stacked on the active matrix substrate so as to be in contact with the electromagnetic wave. Detector . 6. The electromagnetic wave detector according to claim 1, wherein the uneven portion is formed at a position that does not overlap the electrode wiring in a stacking direction of the interlayer insulating layer with respect to the electrode wiring . . 2. The electromagnetic wave detector according to claim 1, wherein a portion of the semiconductor layer on the concavo-convex portion is formed such that the thickness gradually decreases toward the outer side of the active matrix substrate. A pixel array region in which a plurality of electrode wirings arranged in a grid pattern, an active element arranged for each grid of these electrode wirings, an interlayer insulating layer, and a plurality of pixel electrodes are sequentially stacked, and the pixel array An active matrix substrate having a peripheral region surrounding the region;
In the electromagnetic wave detector comprising an electromagnetic conductive semiconductor layer formed on a surface of the active matrix substrate so as to cover the pixel array region and at least a part of the peripheral region,
The interlayer insulating layer is formed in at least a part of the pixel array region and the peripheral region, and a region that contacts the semiconductor layer in the interlayer insulating layer of the peripheral region of the active matrix substrate has a recess and a protrusion. An uneven portion consisting of at least one of the portions is formed An electromagnetic wave detector characterized by that. On an insulating substrate,
Electromagnetic wave detection in which a plurality of electrode wirings arranged in a grid and active elements, interlayer insulating layers, a plurality of pixel electrodes, and semiconductor layers having electromagnetic conductivity are sequentially stacked for each grid of these electrode wirings In the vessel
An electromagnetic wave detector, wherein an uneven portion including at least one of a concave portion and a convex portion is formed in at least a part of a region in contact with the semiconductor layer in the interlayer insulating layer. 10. The electromagnetic wave detector according to claim 9, wherein a surface of the uneven portion is covered with an inorganic layer capable of obtaining a higher bonding strength than the surface of the uneven portion with respect to the semiconductor layer. The surface of the concavo-convex portion is covered with an inorganic layer that can obtain higher bonding strength than the surface of the concavo-convex portion with respect to the semiconductor layer, and the inorganic layer is made of the same material as the pixel electrode. The electromagnetic wave detector according to claim 9. The concavo-convex portion is formed in the interlayer insulating layer in a region in contact with the insulating substrate and has a structure penetrating the interlayer insulating layer, and between the interlayer insulating layer and the insulating substrate in the concavo-convex portion, The electromagnetic wave detector according to claim 9, wherein an inorganic layer capable of obtaining a bonding strength higher than that of the surface of the insulating substrate is formed on the semiconductor layer. On an insulating substrate,
A plurality of electrode wires arranged in a lattice pattern;
Active elements arranged for each grid of these electrode wirings,
An interlayer insulating layer provided in an upper layer of the electrode wiring and the active element;
A plurality of pixel electrodes formed on the interlayer insulating layer;
The interlayer insulating layer is disposed so as to cover a pixel array region in which the electrode wirings are arrayed in a lattice pattern and at least a part of a peripheral region surrounding the pixel array region, and is disposed in the peripheral region On at least a part of the upper surface of the interlayer insulating layer, an uneven portion comprising at least one of a recessed portion and a protruding portion is formed,
A bonding layer having a coefficient of thermal expansion different from that of the insulating substrate is formed so as to cover the pixel array region and at least a part of the peripheral region, and the bonding layer is stacked on the uneven portion in the peripheral region. An active matrix substrate characterized by that.

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