JP4107661B2 - Active matrix substrate and manufacturing method thereof - Google Patents

Description

  The present invention relates to an active matrix substrate and a manufacturing method thereof.

  An active matrix substrate that is widely used at present and that can be driven by a matrix using an active element is formed by repeating a photo-etching process in which a thin film is deposited on a support substrate and processed into a shape capable of exhibiting a function.

  When forming the matrix wiring on the active matrix substrate, for example, after forming the first wiring layer so as to be connected to the active element through the through hole portion, the shape processing of the first wiring layer is performed. Thereafter, an interlayer insulating layer is formed in order to prevent a short circuit at a matrix intersection between the wirings and coupling between the wirings, and a second wiring layer is formed through a through hole opened in the interlayer insulating layer. At this time, film formation / shape processing of the first wiring layer, film formation / shape processing of the interlayer insulating film, and film formation / shape processing of the second wiring layer are required for forming the matrix wiring after forming the active element. Become.

  On the other hand, due to recent advances in printing technology, attempts to form matrix wiring using a printing method have also been studied (see, for example, Patent Document 1). In this case, since the film formation and the shape processing at the time of forming the matrix wiring can be performed at one time, it is considered effective for cost reduction.

  When the matrix wiring is formed by the printing method, for example, the first wiring layer is formed and processed at once using the printing method so as to be connected to the active element through the through hole portion. After that, an interlayer insulating layer is formed to prevent short circuit at the matrix intersection of the wirings and coupling between the wirings, and the second wiring layer is similarly printed through the through hole opened in the interlayer insulating layer. Use to form. At this time, in order to form the matrix wiring after the formation of the active element, it is necessary to perform the first wiring printing, the interlayer insulating film formation / shape processing, and the second wiring printing.

  When an active matrix substrate is manufactured by the method described above, there are the following problems.

  First, when the matrix wiring is manufactured without using the printing method, as described above, three or more film forming steps and shape processing steps are required in addition to the active element forming step. In order to perform these steps, a lot of time and members are required. The interlayer insulating layer needs to have a sufficiently thick film thickness of, for example, about 0.5 μm in order to prevent a short circuit or wiring coupling at the intersection between the wirings. For this reason, in order to avoid contact failure between the matrix wiring and the active element, the through hole portion needs to have a sufficient size and a gentle inclination angle. For this reason, the area required for the electrode contact of the active element increases. For example, when an active matrix substrate is used for a display, the aperture ratio is reduced.

Further, even when the matrix wiring is manufactured using the printing method, when the printing method such as the inkjet method is used, the wiring forming process is reduced, but the stability of the wiring pattern is lacking. That is, when coating is applied to a portion having a step, the portion where the step is low tends to be thick because droplets tend to accumulate, and the portion where the step is high tends to be thin. Also, with respect to the through hole portion, in order to avoid contact failure, it is necessary to drop a sufficient amount of liquid into the through hole portion. At this time, in the normal active element, the through-hole opening is formed at a position higher than the wiring formation surface as compared with the wiring formation position, so that ink or the like does not easily flow. Therefore, it is necessary to strictly control the ink head to the through hole position. Further, in the stepped portion or the inclined portion, ink or the like flows to a low position formed by the step or the inclined portion, and the original pattern is deformed. Since the matrix wiring and the contact portion are relatively close to each other around the active element, this deformation may cause a short-circuit between lines and a capacitive coupling.

On the other hand, a large number of thin film transistors are densely formed in advance on a support substrate (transfer source substrate), and the required number of thin film transistors from the transfer source substrate is formed on a support substrate (transfer destination substrate) different from the transfer source substrate. There has been proposed a method of transferring to (see, for example, Patent Document 2). However, even when this transfer technique is used, the same wiring formation technique as described above is used for the wiring formation.
JP 2003-251243 A (page 5-20) JP 2001-7340 (page 3-7, FIG. 15)

  As described above, an active matrix substrate that can be manufactured with a small number of steps and has good contact characteristics and a method for manufacturing the same cannot be obtained.

  In view of this problem, an object of the present invention is to provide an active matrix substrate that can be manufactured with a small number of steps, has a wide aperture ratio, and has good contact characteristics, and a method for manufacturing the same.

  Therefore, the present invention provides a substrate, an adhesive layer provided on the substrate so as to have a first groove having at least one side surface as an inclined surface, an active element provided on the inclined surface, and a bottom portion of the groove. The first wiring connected to the first electrode provided on the bottom side of the active element, the insulating layer provided on the first wiring, and the adhesive layer in a direction different from the first wiring. Provided is an active matrix substrate comprising a second wiring provided on an upper surface and an insulating layer and connected to a second electrode provided on an upper side of a groove of an active element.

  In the present invention, the height of the upper surface of the adhesive layer and the surface of the insulating layer from the substrate surface may be substantially equal.

  In the present invention, a support layer may be provided between the adhesive layer and the active element.

  In the present invention, the active element has the third electrode, the pixel electrode is provided on the upper surface of the adhesive layer, and the contact electrode of the pixel electrode is provided on the upper side of the groove. You may connect with the electrode.

  In the present invention, the second groove may be formed in a region corresponding to the second wiring on the substrate.

  In the present invention, a recess may be formed in a region where the contact electrode and the third electrode on the substrate are connected.

  In the present invention, the angle formed between the inclined surface and the substrate surface may be not less than 20 degrees and not more than 85 degrees.

  In the present invention, the end surface of the support layer is an inclined end surface, and at least one of the first electrode and the second electrode may extend to the inclined end surface.

  In the present invention, the wettability between the first wiring and the first electrode may be greater than the wettability between the first wiring and the adhesive layer.

  In the present invention, the wettability between the second wiring and the second electrode may be greater than the wettability between the second wiring and the adhesive layer.

  In the present invention, the wettability between the first wiring or the second wiring and the adhesive layer is greater than the wettability between the first wiring or the second wiring and the active element. good.

  Further, the present invention is arranged on a substrate, an adhesive layer provided on the substrate, having a plurality of grooves extending in a substantially constant direction and inclined at least one wall surface, and the inclined wall surface, A plurality of active element groups having a plurality of electrodes and a first wiring that is arranged at the bottom of the groove and commonly connects the electrodes located on the bottom side of the groove among the active element groups arranged in the same groove Each of the electrodes located on the upper side of the groove among the electrodes of the active element group disposed on the adhesive layer so as to exceed the insulating layer and the insulating layer provided on the first wiring, and disposed in different grooves And an active matrix substrate, characterized in that the active matrix substrate is provided.

  The present invention is also provided with a step of forming an active element having a first electrode and a second electrode on a transfer source substrate, and a groove having at least one side surface as an inclined surface on the transfer destination substrate. Forming an adhesive layer and transferring the active element from the transfer source substrate onto the inclined surface of the transfer destination substrate so that the first electrode is disposed on the bottom side of the groove and the second electrode is disposed on the upper side of the groove A step of forming a first wiring connected to the first electrode of the active element on the bottom side of the groove, a step of forming an insulating layer on the first wiring, and a second electrode of the active element And a step of forming a second wiring on the adhesive layer and the insulating layer so as to be in a direction different from that of the first wiring.

  According to the present invention, it is possible to provide an active matrix substrate that can be manufactured with a small number of steps, has a wide aperture ratio, and has good contact characteristics, and a method for manufacturing the same.

  In the active matrix substrate and the manufacturing method thereof according to the embodiment of the present invention, active elements are formed on a transfer source substrate different from the active matrix substrate, and collectively formed on an intermediate transfer substrate that can be temporarily supported. After the transfer, it is transferred again to the active matrix substrate. Then, when transferring the active element to the active matrix substrate, the active element is attached to be inclined with respect to the substrate surface.

  The active matrix substrate of this embodiment is shown in FIG.

As shown in FIG. 1, the active matrix substrate of this embodiment includes a transfer destination substrate 11 and an adhesive layer 12 provided on the transfer destination substrate 11. The adhesive layer 12 has a groove having at least one side surface as an inclined surface, and the other side surface of the groove is not shown in FIG. The adhesive layer 12 has a flat surface (upper surface) following the inclined surface. On the inclined surface of the adhesive layer 12, a support layer 13 and an active element 14 provided on the support layer 13 are provided, and the active element 14 includes a first electrode 19 and a second electrode 18. The first electrode 19 is provided on the bottom surface side of the groove, and the second electrode 18 is provided on the upper side of the groove, that is, on the upper surface side of the adhesive layer 12. For example, when a three-terminal thin film transistor is used as the active element 14, for example, the first electrode 19 is used as a contact portion connected to the gate electrode, and the second electrode 18 is used as a contact connected to the source or drain electrode. Part. With such a configuration, the first electrode 19 and the second electrode 18 can be positioned at different heights from the surface 11 of the transfer destination substrate.

  For this reason, it is possible to use the arrangement of the first electrode 19 and the second electrode 18 at different heights with respect to the transfer destination substrate surface 11 when forming the matrix wiring. That is, when a wiring connected to the first electrode 19, for example, a wiring corresponding to a gate line, is formed using a drawing method with a liquid ink in which liquid or fine particles are dispersed at the time of wiring formation, Even when the portion has a somewhat complicated shape, as shown in FIG. 2, the ink 42 discharged from the discharge portion 41 can wrap around due to the fluidity of the liquid. Therefore, a stable contact can be formed as compared with the conventional wiring formation to the through hole. Further, in the case of the inclined contact portions, it is possible to make the wiring height, that is, when the liquid is used, the liquid surface height almost constant over the entire wiring.

  The formation of the wiring connected to the first electrode 19 and the second electrode 18 when the active element 14 is attached to the inclined surface of the adhesive layer 12 will be described.

  FIGS. 3 to 5 are diagrams for explaining the liquid level of the wiring when the wiring connected to the first electrode 19 is formed.

  In FIG. 3, the height A is the maximum height from the substrate surface on the side surface on the groove side of the support layer 13, and the height B is the maximum height from the substrate surface in the exposed portion of the first electrode 19. The height C is the maximum height from the substrate surface on the side surface of the active element 14 on the groove side. In the case of forming a wiring to be connected to the first electrode 19, it is preferable to adjust the amount of ink so that the liquid level is B as shown in FIG. That is, it is preferable to set the highest position that is farthest from the surface of the transfer destination substrate 11 in the region where the first electrode 19 is formed. In FIG. 3, if the liquid level is between A and C, the first electrode 19 and the wiring can be joined. Therefore, if the liquid level is between A and C, A good margin can be maintained.

  In FIG. 4, the height D is the same as the height C and is the maximum height from the substrate surface on the side of the active element 14 on the groove side, and the height E is the same as the thickness of the adhesive layer 12. The depth F is the maximum height from the substrate surface on the side surface opposite to the groove of the active element 14. When the electrode and the wiring are brought into contact via a through hole or the like provided on the upper surface of the active element 14, it is preferable to provide a liquid level between D and F as shown in FIG. It is most preferable to set E to the liquid level when the position is farthest from the substrate surface.

  In FIG. 5, the height G is the maximum height from the substrate surface on the side surface opposite to the groove of the support layer 13, and the height H is the maximum height from the substrate surface of the second electrode 18. When forming the wiring connected to the second electrode 18, as shown in FIG. 5, it is possible to maintain the bonding between the second electrode 18 and the wiring by providing a liquid level between G and H. It becomes. In all of these, the liquid level of the wiring is set to be higher than the height in contact with the electrode and less than the height at which the wiring comes into contact with the other electrode.

6 to 10 are diagrams for explaining the wettability of the ink liquid when the wiring connected to the first electrode 19 and the insulating layer provided on the wiring are formed of the ink liquid. The insulating layer provided on the wiring connected to the first electrode is provided to prevent a short circuit between the wiring connected to the first electrode and the wiring intersecting with the wiring. The wettability is the difference in the contact angle of a certain liquid with the solid surface. Therefore, when the ink liquid is in contact with two solid surfaces having different contact angles, the solid surface with a smaller contact angle is preferentially wet.

  FIG. 6 shows a case where the wettability with respect to the first electrode 19 of the ink liquid 72 forming the wiring is equal to the wettability with respect to the adhesive layer 12. In this case, when the transfer destination substrate 11 is placed horizontally, the liquid surface of the ink liquid 72 is parallel to the substrate surface.

  FIG. 7 shows the case where the wettability of the ink liquid 73 with respect to the first electrode 19 is greater than the wettability with respect to the adhesive layer 12. In this case, even when the amount of the ink liquid 73 is relatively small, it is possible to form a wiring having excellent contact with the first electrode 19.

  FIG. 8 is an explanatory diagram of wettability when a wiring is formed with the ink liquid 74 and then an insulating layer is formed on the wiring with the ink liquid 75. Here, when the insulating layer using the ink liquid 75 is formed, it is desirable that the liquid level is substantially horizontal between the active element 14 and the adhesive layer 12. Therefore, it is desirable that the surface of the active element 14 and the surface of the adhesive layer 12 have substantially the same wettability with respect to the ink liquid 75.

  FIG. 9 shows a case where the wettability of the ink liquid 73 with respect to the adhesive layer 12 is greater than the wettability with respect to the active element 14. In this case, even when the amount of the ink liquid 73 is relatively large, it is possible to prevent the wiring connected to the first electrode 19 from protruding and coming into contact with other electrodes of the active element 14.

  FIG. 10 is an explanatory view of the wettability when a wiring is formed with the ink liquid 77 and then an insulating layer is formed with the ink liquid 78 on the wiring. In this case, a surface treatment is applied to the flat surface of the adhesive layer 12, that is, the surface not touched by the ink liquid 78 so that the contact angle with the ink liquid 78 is increased. At this time, even if the dripping amount of the ink liquid 78 is too large as shown in FIG. 10, the ink liquid 78 can be prevented from spreading to the surface of the adhesive layer 12.

  As described with reference to FIGS. 6 to 10, when a wiring or an insulating layer is formed by a printing method using an ink liquid, not only the liquid surface height but also the wettability difference in the area where the ink liquid contacts is used. It can be seen that the process margin can be widened. This is true for all electrodes and insulating layers formed by the printing method.

  Next, a manufacturing method for the active matrix substrate of the present embodiment will be described.

  FIG. 11 to FIG. 14 are diagrams for explaining the steps until the active element is formed on the transfer source substrate in this embodiment, where (a) is a plan view and (b) is ee ′ of (a). FIG.

As shown in FIG. 11, a separation layer 52 made of a silicon nitride film or the like is formed on a transfer source substrate 51 made of non-alkali glass made of, for example, aluminoborosilicate by an electron cyclotron resonance (ECR) sputtering method with a thickness of about 50 nm. After forming the film to have a thickness of −250 nm, heat treatment is performed at about 450 ° C. for about 1 hour in a nitrogen atmosphere or the like. On this, a support layer 53 made of a silicon oxide film or the like by a plasma enhanced chemical vapor deposition method (PECVD method) using silane as a raw material is formed to have a thickness of about 500 nm to 700 nm. In addition, a magnetron sputtering method is used to deposit a metal such as Al, Mo, W, Ta, or Ti, or an electrode layer made of such a metal, or an alloy thereof, and then a photoetching process is performed. In this manner, the gate electrode 31 and the first electrode 19 are formed. At this time, it is preferable to form the first electrode 19 in a state where each contact portion is electrically connected without being formed independently, because electrostatic breakdown can be prevented at the time of manufacturing.

  As shown in FIG. 12, after forming a gate insulating film having a thickness of about 400 nm made of a silicon-based insulating material such as a silicon oxide film by using PECVD so as to cover the gate electrode 31 and the first electrode 19, The gate insulating portion 32 is formed using a photoetching process. On this, an amorphous silicon layer with a thickness of about 50 nm, a silicon nitride layer with a thickness of about 100 nm to be the channel protective layer 34, and the like are formed by PECVD. The silicon nitride layer is processed using a photoetching process so as to have a shape slightly smaller than the gate electrode 31 to form a channel protective layer 34. After processing the channel protective layer 34, an amorphous silicon layer of about 30 nm doped with phosphorus (P) is formed by PECVD using silane, phosphine, or the like as a raw material, and then Mo or the like is used using a magnetron sputtering method. Is deposited to a thickness of about 30 nm. By using a photoetching process, the amorphous silicon layer, the amorphous silicon layer doped with phosphorus, and the Mo layer are processed into an island shape so as to cover the gate insulating portion. This is referred to as a semiconductor layer 33.

  As shown in FIG. 13, after depositing Mo, Al, W, Ti, an alloy thereof, or a laminated film thereof by using a magnetron sputtering method or the like, a photoetching process is used to form the source electrode 35 and the source electrode 35. The subsequent second electrode 18, drain electrode 36, and subsequent third electrode 22 are formed. At this time, as shown in FIG. 13A, the source electrode 35 and the drain electrode are connected to each other by connecting the second electrode 18 and the third electrode 22 adjacent to each other, and further adjacent to each other. The first electrode 19 of the line is also connected. This is because by adopting such a structure, electrostatic breakdown in each thin film transistor can be prevented.

  As shown in FIG. 14, after forming a silicon oxide film or the like having a thickness of about 500 nm to 700 nm as a protective layer 37 for protecting the thin film transistor portion using PECVD, a contact hole portion is formed using a photoetching process. And processing into a shape corresponding to each active element region. In the thin film transistor, only the first electrode 19, the second electrode 18, and the third electrode 22 are exposed, and the others are covered with the support layer 53 and the protective layer 37.

  FIGS. 15 to 17 are diagrams for explaining a process of temporarily transferring the active elements collectively from the transfer source substrate to the intermediate transfer substrate in this embodiment. FIG. 15A is a plan view, and FIG. ) Is a cross-sectional view taken along line ff ′ of FIG. 15A, and FIGS. 16 and 17 are cross-sectional views corresponding to FIG. 15B.

  As shown in FIG. 15, a separation layer 52 and a support layer 53 are laminated on the transfer source substrate 51, and the layers other than the first electrode 19, the second electrode 18, and the third electrode 22 are protected thereon. An active element covered with a layer 37 is provided.

  As shown in FIG. 16, for example, an organic resin portion 54 that is locally foamed by UV light is formed on a transfer source substrate 51 provided with an active element covered with a protective layer 37 by a spin coating method or the like. After the application, an intermediate transfer substrate 55 having excellent UV transparency such as a quartz substrate is bonded. At this time, it is desirable to carry out in a reduced pressure atmosphere so that air bubbles and the like are not mixed between the organic resin portion 54 and the intermediate transfer substrate 55.

As shown in FIG. 17, the transfer source substrate 51 used to form the active element is removed. First, the transfer source substrate 51 is polished to about 50 μm-80 μm using a mechanical polishing method using an abrasive. At this time, the abrasive may have a large particle size at first, but a material having a smaller particle size may be used as the thickness of the substrate is reduced. Further, when the substrate thickness is less than 50 μm-80 μm, the active element is damaged due to deformation of the transfer source substrate 51 or generation of static electricity due to stress at the time of polishing, etc. Therefore, the mechanical polishing is preferably about 50 μm-80 μm. . Next, the transfer source substrate 51 is etched using a chemical polishing method using an etchant containing hydrofluoric acid as a main component until the transfer source substrate 51 can be substantially removed. Here, when the transfer source substrate 51 is removed, the surface of the separation layer 52 made of a silicon nitride film or the like formed by ECR sputtering or the like is exposed. Here, the etching rate ratio between the glass substrate and the silicon nitride film can be increased by adjusting the addition amount of ammonia, sulfuric acid or the like in the hydrofluoric acid etchant at the time of etching. For this reason, the transfer source substrate 51 can be completely removed. At this time, since the separation layer 52 has translucency, it may be left as it is, or may be removed to expose the surface of the support layer 53. FIG. 17 shows a case where the separation layer 52 is not left. Further, by performing a photo etching process on the surface from which the transfer source substrate 51 has been removed, shape processing is performed from the back surface corresponding to the active element region. The shape processing at this time is separation of the separation layer 52, the support layer 53, and the common first electrode 19, second electrode 18, and third electrode 22 that were in contact with the glass substrate surface. . By this etching process, each active element can be separated into independent active element portions.

  FIGS. 18 to 21 are views for explaining a process of selectively transferring the active element from the intermediate transfer substrate to the transfer destination substrate in the present embodiment. FIG. 18A is a plan view, and FIG. It is sectional drawing between hh 'of a), and FIGS. 19-21 is sectional drawing corresponding to FIG.18 (b).

  As shown in FIG. 18, by using a photoetching process or the like on the transfer destination substrate 56, a signal line groove 61 is formed in a region where a signal line is to be formed, and a contact formation planned region where a contact with the pixel electrode is planned. A recess 62 is formed. As the transfer destination substrate 56, an alkali-free glass substrate or the like widely used in liquid crystal displays can be used. The signal line groove 61 and the recess 62 may be formed by forming a photosensitive novolac resin, photosensitive polyimide, or the like on the transfer destination substrate 56 on one side, and forming the groove and the recess using a photo process. An adhesive layer 57 made of an acrylic resin or the like is formed on the transfer destination substrate 56, and a scanning line groove 58 for forming a scanning line later is formed. Further, in the region where the signal line groove 61 and the recess 62 are provided, a recess is formed on the adhesive layer 57 in a self-aligning manner. As the adhesive layer 57, urea resin, melanin resin, phenol resin, epoxy resin, urethane resin and the like can be used in addition to the acrylic resin.

  As shown in FIG. 19, an inclined surface 59 is formed on at least one of the side surfaces of the scanning line groove 58 by a photo process. The inclination of the end of the adhesive layer 57 that determines the inclination angle of the inclined surface 59 is controlled by the exposure time of the photo process and the baking temperature of the acrylic resin. The inclination angle is preferably 20 degrees or more and 85 degrees or less. By setting it to 20 degrees or more, the wiring to be formed later can be formed stably, and by setting it to 85 degrees or less, the selective transferability of the active element 14 can be kept high. Then, the intermediate transfer substrate 55 to which the active element 14 is bonded and the transfer destination substrate 56 in which the inclined surface 59 is formed on the adhesive layer 57 are placed so that the active element 14 to be transferred is at a predetermined position on the inclined surface 59. Overlapping.

As shown in FIG. 20, among the active elements 14 provided on the intermediate transfer substrate 55, the organic resin portion 54 at a position corresponding to the active element 14 to be transferred is irradiated with UV light from the intermediate transfer substrate 55 side. At this time, in the region irradiated with the UV light, the organic resin part 54 that is foamed and peeled off by the UV light is foamed and expands in volume. For this reason, the active element 14 before being transferred is horizontal to the substrate surfaces of the intermediate transfer substrate 55 and the transfer destination substrate 56, but is inclined and bonded to the inclined surface 59 of the adhesive layer 57 at the time of the foaming separation. It will be. Thereafter, an annealing process at about 120 ° C. is performed so that the transferred active element 14 is sufficiently fixed to the inclined surface 59 of the adhesive layer 57.

  As shown in FIG. 21, when the intermediate transfer substrate 55 and the transfer destination substrate 56 are separated, the active element 14 to be transferred is transferred to the inclined surface 59 of the transfer destination substrate 56. In the transfer source substrate 51 and the intermediate transfer substrate 55, the active elements 14 are formed densely, and selectively transferred from the active elements 14 to the transfer destination substrate 56.

  22 to 24 are views for explaining a process of forming a wiring for the active element on the transfer destination substrate in this embodiment, where (a) is a plan view and (b) is a cross section between hh ′. FIG.

As shown in FIG. 22, in a state where the active element 14 is transferred to the transfer destination substrate 56, the scanning line groove 58 is formed in the portion corresponding to the scanning line, and the signal line groove 61 is formed in the portion corresponding to the signal line. As shown in FIG. 23, a groove formed on the adhesive layer 57 is formed on the adhesive layer 57 in a self-aligned manner on the portion corresponding to the contact region with the pixel electrode. In addition, an appropriate amount of ink liquid is dropped along substantially the center of the scanning line groove 58. This ink liquid is dropped by an ink jet method using a material in which silver fine particles exhibiting conductivity are dispersed. At this time, since the shape of the ink liquid changes in accordance with the position of the side surface of the scanning line groove 58, a slight positional deviation and non-uniform drop amount can be adjusted in a self-aligning manner. Here, an annealing process is performed at about 150 ° C. for volatilization of the ink solvent and solidification of the ink, whereby the scanning line 63 connected to the first electrode 19 is formed. An insulating layer 64 is formed on the scanning line 63 by an inkjet method. At this time, an imide-based resin having sufficient insulating properties after firing is employed as the ink liquid material. Here, the imide-based resin can be converted into a polyimide having excellent insulating properties through a firing step. As the material of the insulating layer 64, urea resin, phenol resin, epoxy resin, and the like can be used.

  Details of forming the scanning line 63 are shown in FIGS. 25 and 26 are sectional views taken along line g-g 'in FIG. Immediately after the ink is dropped into the scanning line groove, the liquid level of the scanning line 63 is a uniform layer as shown in FIG. 25. However, after the ink drying and firing steps, the ink solidification is large. Due to the volume change, as shown in FIG. 26, the concave portion of the region 82 corresponding to the signal line groove retains its shape. For this reason, the recess of the signal line groove can be maintained even at the intersection of the scanning line and the signal line. If the height of the surface of the insulating layer 64 from the surface of the transfer destination substrate 56 is substantially the same as that of the upper surface of the adhesive layer 57, the height of the recess of the signal line groove between the adhesive layer 57 and the insulating layer 64 is increased. Can be almost equal.

  As shown in FIG. 24, the signal line 65 and the contact electrode are formed in the region where the adhesive layer 57 is recessed by the formation of the signal line groove 61 and the recess 62 by using an ink jet method using the same material as that for forming the scanning line 63. 66 is produced. At this time, a sufficient amount of ink is dropped on the signal line 65 and the contact electrode 66 so that the signal line 65 and the second electrode 18 and the contact electrode 66 and the third electrode 22 are connected with high reliability. As described above, coating is performed twice by the ink jet method.

In order to use as an active matrix substrate for a transmissive liquid crystal display, it is necessary to form pixel electrodes. The pixel electrode may be manufactured as follows. First, after forming the signal line 65 and the contact electrode 66, an acrylic resin (not shown) that can be processed by a photo process is formed on the entire surface with a thickness of about 0.8 μm, and then the through-hole is passed through the acrylic resin in the contact electrode 66 portion. A hole is formed. This acrylic resin portion becomes an interlayer insulating film. Here, the interlayer insulating film protects signal lines and contact electrodes, and has an effect of flattening the surface of the matrix substrate. After this interlayer insulating film is formed, an oxide of indium and tin that is connected to the contact electrode 66 through the through hole is formed to a thickness of about 100 nm by RF magnetron sputtering, and then a desired etching process is performed using a photoetching process. The pixel electrode 67 is shaped.

  The active matrix substrate of the present embodiment completed in this way is shown in FIGS. 27 to 30 and 42. 27 is a plan view showing one pixel portion of the active matrix substrate of the present embodiment, FIG. 28 is an enlarged plan view of the active element 14, and FIG. 29 is a cross-sectional view taken along aa ′ in FIG. 30 is a cross-sectional view taken along the line cc ′ in FIG. FIG. 42 is a plan view showing the active elements of FIG. 27 arranged in a matrix in the matrix direction.

  As shown in these drawings, the active matrix substrate of this embodiment is provided with a signal line groove 61 and a recess 62 for making contact between the drain electrode and the pixel electrode on the transfer destination substrate 56, and An adhesive layer 57 is provided on the top. The adhesive layer 57 is patterned to provide a scanning line groove 58, and at least one side surface of the scanning line groove 58 is an inclined surface, and the active element 14 provided on the support layer 53 is provided on the inclined surface. It is glued. The first electrode 19 of the active element 14 is provided on the bottom side of the scanning line groove 58 and is connected to the scanning line 63 formed in the scanning line groove 58. On the scanning line 63, an insulating layer 64 for preventing a short circuit with the signal line 65 intersecting with the scanning line 63 is provided in parallel with the scanning line 63. A recess corresponding to the signal line groove 61 provided in the transfer destination substrate 56 on the adhesion layer 57 and the insulating layer 64 is formed in a self-aligned manner, and a signal line 65 is provided on the recess to provide a second line. The electrode 18 is connected. Further, in the region corresponding to the recess 62 provided in the transfer destination substrate 56 on the adhesive layer 57, a recess is formed in a self-aligned manner, and a contact electrode 66 is provided on the recess and is connected to the third electrode 22. To do. An interlayer insulating film 101 is provided thereon, a through hole 102 is opened in the recess 62 region, and a pixel electrode 67 and a contact electrode 66 formed thereon are connected.

  Each active element is shown in FIGS. 31 is a plan view of the active element of the present embodiment, FIG. 32 is a cross-sectional view taken along d-d ′ in FIG. 31, and FIG. 33 is a cross-sectional view taken along e-e ′ in FIG.

  As shown in these drawings, in the active element of the present embodiment, a patterned gate electrode 31 is formed on a support layer 53, and a gate insulating film 32 is provided so as to cover the gate electrode 31. A semiconductor layer 33 is provided on the gate insulating film 32, and a channel protective film 34 having a size slightly smaller than that of the gate electrode 31 is provided thereon. A source electrode 35 and a drain electrode 36 separated by a channel protective film 34 are provided on the semiconductor layer 33, and these are covered with a protective film 37 and a support layer 53 provided thereon. Only the first electrode 19 connected to the gate electrode 31, the second electrode 18 connected to the source electrode 35, and the third electrode 22 connected to the drain electrode 36 are exposed without being covered with the protective layer 37.

As described above, in the present embodiment, the active element formed on the transfer source substrate is formed on the transfer destination substrate with a groove formed in the adhesive layer, and the side surface of the groove is attached to the inclined surface as an inclined surface. By using the transfer method as described above, there is a feature that many active matrix substrates can be manufactured from one transfer source substrate. Further, the structure is such that a part of the ink that forms the wiring is opened so that the ink is easily impregnated. For the stability of the shape such as the line width when forming the matrix wiring, a layer (adhesive layer) formed on the matrix substrate side can be used to bond the active element. That is, if a groove corresponding to the wiring is formed, the ink can be changed in accordance with the shape of the groove. Usually, in wiring formation by a printing method, it is necessary to form this groove structure in advance using, for example, an acrylic resin that can be patterned by a photo process. In this case, a photo process for wiring formation is added. Therefore, the advantages of the printing method will not be fully utilized. However, in this embodiment, since the adhesive layer for arranging the active elements in an inclined manner can be used for stabilizing the shape of the wiring as it is, this photo process can be reduced, and the advantage of the printing method that reduces the number of steps can be utilized. become.

  In addition, similarly to the formation of the gate line using the groove of the adhesive layer, the line width control using the step coverage of the adhesive layer can be performed for the formation of the signal line, the contact electrode, and the like. That is, a step is formed in advance on the support substrate surface constituting the active matrix at a portion corresponding to the signal line and a portion positioned at the contact electrode. This may be because the surface of the support substrate may be processed by a photoetching process, or the portion located on the signal line or contact electrode may be patterned using, for example, an imide resin that can be processed by the photoprocess. good. The signal line equivalent shape and the contact electrode equivalent shape can be maintained on the surface of the adhesive layer even if an adhesive layer for tilting is formed. For this reason, for example, even when forming a signal line or a contact electrode using liquid ink in which liquid or fine particles are dispersed, contact characteristics are good using the same technique as that for forming a gate line, wiring Wiring can be formed with a small non-uniform width and a large resistance cross-sectional area.

  In this embodiment, a photo process is not required when forming an interlayer insulating film for matrix wiring. This is because when one matrix wiring is formed, the wiring is located at a lower position than the top surface of the substrate. Conventionally, after forming an insulating film on the entire surface of a substrate, an interlayer insulating film has to be formed by a photoetching process through hole for contact. However, in this embodiment, since the interlayer insulating film can be formed in a self-aligned manner by dropping the insulating ink into the groove, the number of steps can be reduced. Therefore, the contact portion between the electrode and the wiring can reduce the structure of opening a through hole and connecting through the through hole as much as possible. For this reason, it is possible to reduce the area occupied by the contact portion.

  Moreover, in the wiring formation by the normal printing method, the resistance cross-sectional area depends on the viscosity of the ink used at the time of printing, but generally the wiring film thickness after annealing solidification is at most submicron thickness. In order to increase the film thickness, a process such as overcoating is required. This is because when a large amount of ink is dropped at a time, the wiring width increases as the wiring thickness increases. However, in this embodiment, as shown in FIG. 34, the transfer destination substrate 11 is provided with a groove 112, and the adhesive layer 12 forms a similar groove in a self-alignment manner with this groove. Since the width is limited by the adhesive layer 12, it is possible to increase the wiring thickness more uniformly without increasing the wiring width by dropping a large amount of ink at a time. In addition, since the active elements arranged in an inclined manner have their contact portions arranged in an inclined manner, it is desirable that the wiring thickness be relatively thick. For this reason, since the resistance cross-sectional area as wiring can be taken widely, the resistance reduction of wiring is realizable. Further, as shown in FIG. 35, using the same groove as that for forming the wiring 113, the interlayer insulating film 114 also uses a printing method such as an ink jet method as in the case of forming one matrix wiring. It can be formed by dripping a liquid having excellent insulating properties into the groove and then curing it.

  Next, a second embodiment of the present invention will be described. This embodiment is a structure for maintaining good contact characteristics of the active element even when the inclination angle of the groove of the adhesive layer is gentle. As for the active matrix substrate of this embodiment, only the parts different from the first embodiment will be described, and the same parts will be omitted.

  In the active matrix substrate of this embodiment, as shown in FIG. 36, the side surface of the support layer 13 is an inclined surface, and the first electrode 121, the second electrode 122, and the third electrode are also formed on the inclined surface. The difference from the first embodiment is that (not shown) extends.

For this reason, as shown in FIG. 36, the contact area between each electrode and the wiring is widened, so that good contact characteristics can be maintained. Furthermore, when this structure is adopted, as shown in FIG. 37, the inclination angle of the groove to which the active element is bonded is smaller than that of a normal one (represented by α), and is gentle, for example, about 15 to 25 degrees. Even in the case (represented by β), good connection characteristics can be obtained.

  Each active element of this embodiment is shown in FIGS. 38 is a plan view of the active element of the present embodiment, FIG. 39 is a cross-sectional view taken along the line k-k ′ in FIG. 38, and FIG. 40 is a cross-sectional view taken along the line j-j ′ in FIG.

  As shown in these drawings, the active element of the present embodiment has a gate electrode 31 patterned on a support layer 13 having four side surfaces 123 having an inclination angle, and a gate so as to cover the gate electrode 31. An insulating film 32 is provided. A semiconductor layer 33 is provided on the gate insulating film 32, and a channel protective film 34 having a size slightly smaller than that of the gate electrode 31 is provided thereon. On the semiconductor layer 33, a source electrode 35 and a drain electrode 36 separated by a channel protective film 34 are provided, and these are covered with a protective film 37 and a support layer 13 provided thereon. As shown in FIG. 40, the first electrode 121 connected to the gate electrode 31 extends to the inclined surface 126. As shown in FIG. 38, the second electrode 122 connected to the source electrode 35 extends to the inclined surface 123. As shown in FIG. 39, the third electrode 124 connected to the drain electrode 36 extends to the inclined surface 125. These are exposed without being covered with the protective layer 37.

  Only the differences from the first embodiment of the method for manufacturing the active matrix substrate of the present embodiment will be described.

  As shown in FIG. 41, a silicon nitride film 52 or the like is formed on a substrate 51 for forming an active element by an electron cyclotron resonance (ECR) sputtering method to a thickness of about 50 to 250 nm, and then about 450 ° C. in a nitrogen atmosphere. Heat treatment for about 1 hour. On this, a silicon oxide film 53 and the like are formed to a thickness of about 800 to 1000 nm by plasma enhanced chemical vapor deposition (PECVD) using silane as a raw material. Thereafter, the silicon oxide film 53 is processed into a size corresponding to the base of the active element by using a photoetching process. Thereby, an inclined surface creating groove 127 is formed around the active element. At this time, it is desirable that the oxide film 53 is processed up to the interface between the silicon oxide film 53 and the silicon nitride film 52 by utilizing the difference in etching rate ratio between the silicon oxide film 53 and the silicon nitride film 52. However, in this case, since the silicon nitride film 52 that plays an important role in removing the glass substrate 51 may be damaged, the etching process may be stopped when the silicon oxide film is processed by leaving a little. . This silicon oxide film 53 is used as the support layer 13. Thereafter, the active matrix substrate of this embodiment is manufactured in the same manner as in the first embodiment except that the first electrode, the second electrode, and the third electrode are also provided on the inclined surface. I can do it.

  Also in this embodiment, the same effect as that of the first embodiment can be obtained, and furthermore, the contact area between each electrode and the wiring is widened, so that good contact characteristics can be maintained.

It is sectional drawing of the active matrix substrate which concerns on the 1st Embodiment of this invention, and is a figure explaining the difference in the height from the board | substrate surface of the electrode formed in the active element. It is sectional drawing of the active matrix substrate which concerns on the 1st Embodiment of this invention, and is a figure explaining the method of forming the wiring connected to the electrode formed in the active element. It is sectional drawing of the active matrix substrate which concerns on the 1st Embodiment of this invention, and is a figure explaining the liquid level height of the ink liquid at the time of forming the wiring connected to the electrode formed in the active element. It is sectional drawing of the active matrix substrate which concerns on the 1st Embodiment of this invention, and is a figure explaining the liquid level height of the ink liquid at the time of forming the wiring connected to the electrode formed in the active element. It is sectional drawing of the active matrix substrate which concerns on the 1st Embodiment of this invention, and is a figure explaining the liquid level height of the ink liquid at the time of forming the wiring connected to the electrode formed in the active element. It is sectional drawing of the active matrix substrate which concerns on the 1st Embodiment of this invention, and is a figure explaining the wettability of the ink liquid at the time of forming the wiring etc. which connect to the electrode formed in the active element. It is sectional drawing of the active matrix substrate which concerns on the 1st Embodiment of this invention, and is a figure explaining the wettability of the ink liquid at the time of forming the wiring etc. which connect to the electrode formed in the active element. It is sectional drawing of the active matrix substrate which concerns on the 1st Embodiment of this invention, and is a figure explaining the wettability of the ink liquid at the time of forming the wiring etc. which connect to the electrode formed in the active element. It is sectional drawing of the active matrix substrate which concerns on the 1st Embodiment of this invention, and is a figure explaining the wettability of the ink liquid at the time of forming the wiring etc. which connect to the electrode formed in the active element. It is sectional drawing of the active matrix substrate which concerns on the 1st Embodiment of this invention, and is a figure explaining the wettability of the ink liquid at the time of forming the wiring etc. which connect to the electrode formed in the active element. It is a figure explaining the manufacturing method of the active-matrix board | substrate which concerns on the 1st Embodiment of this invention, (a) is a top view, (b) is sectional drawing between e-e 'of (a). It is a figure explaining the manufacturing method of the active-matrix board | substrate which concerns on the 1st Embodiment of this invention, (a) is a top view, (b) is sectional drawing between e-e 'of (a). It is a figure explaining the manufacturing method of the active-matrix board | substrate which concerns on the 1st Embodiment of this invention, (a) is a top view, (b) is sectional drawing between e-e 'of (a). It is a figure explaining the manufacturing method of the active-matrix board | substrate which concerns on the 1st Embodiment of this invention, (a) is a top view, (b) is sectional drawing between e-e 'of (a). It is a figure explaining the manufacturing method of the active-matrix board | substrate which concerns on the 1st Embodiment of this invention, (a) is a top view, (b) is sectional drawing between ff 'of (a). It is sectional drawing explaining the manufacturing method of the active matrix substrate which concerns on the 1st Embodiment of this invention. It is sectional drawing explaining the manufacturing method of the active matrix substrate which concerns on the 1st Embodiment of this invention. It is a figure explaining the manufacturing method of the active matrix substrate which concerns on the 1st Embodiment of this invention, (a) is a top view, (b) is sectional drawing between h-h 'of (a). It is sectional drawing explaining the manufacturing method of the active matrix substrate which concerns on the 1st Embodiment of this invention. It is sectional drawing explaining the manufacturing method of the active matrix substrate which concerns on the 1st Embodiment of this invention. It is sectional drawing explaining the manufacturing method of the active matrix substrate which concerns on the 1st Embodiment of this invention. It is a figure explaining the manufacturing method of the active matrix substrate which concerns on the 1st Embodiment of this invention, (a) is a top view, (b) is sectional drawing between h-h 'of (a). It is a figure explaining the manufacturing method of the active matrix substrate which concerns on the 1st Embodiment of this invention, (a) is a top view, (b) is sectional drawing between h-h 'of (a). It is a figure explaining the manufacturing method of the active matrix substrate which concerns on the 1st Embodiment of this invention, (a) is a top view, (b) is sectional drawing between h-h 'of (a). It is sectional drawing between g-g 'of Fig.23 (a). It is sectional drawing between g-g 'of Fig.23 (a). 1 is a plan view showing one pixel of an active matrix substrate according to a first embodiment of the present invention. It is the top view to which the active element of the active matrix substrate which concerns on the 1st Embodiment of this invention was expanded. It is sectional drawing between a-a 'of FIG. It is sectional drawing between cc 'of FIG. 1 is a plan view of an active element according to a first embodiment of the present invention. It is sectional drawing between d-d 'of FIG. It is sectional drawing between e-e 'of FIG. It is sectional drawing which shows the wiring which concerns on the 1st Embodiment of this invention. It is sectional drawing which shows the wiring which concerns on the 1st Embodiment of this invention. It is sectional drawing explaining the active matrix substrate which concerns on the 2nd Embodiment of this invention. It is sectional drawing explaining the active matrix substrate which concerns on the 2nd Embodiment of this invention. It is a top view of the active element which concerns on the 2nd Embodiment of this invention. It is sectional drawing between k-k 'of FIG. It is sectional drawing between j-j 'of FIG. It is sectional drawing explaining the manufacturing method of the active matrix substrate which concerns on the 2nd Embodiment of this invention. It is a top view which shows a mode that the active element of the active matrix substrate which concerns on the 1st Embodiment of this invention is located in a matrix form.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11, 56 ... Transfer destination board | substrate 12, 57 ... Adhesive layer 13, 53 ... Support layer 14 ... Active element 18, 122 ... 2nd electrode 19, 121 ... 1st electrode 22, 124 ... 3rd electrode 31 ... Gate Electrode 32 ... Gate insulating part 33 ... Semiconductor layer 34 ... Channel protective layer 35 ... Source electrode 36 ... Drain electrode 37 ... Protective layers 41, 71, 81, 111 ... Discharge parts 42, 72, 73, 74, 75, 76, 77 78 ... Ink liquid 51 ... Transfer source substrate 52 ... Separation layer 54 ... Organic resin portion 55 ... Intermediate transfer substrate 58 ... Scanning line groove 59 ... Inclined surface 61 ... Signal line groove 62 ... Recess 63 ... Scanning line 64 ... Insulation Layer 65 ... Signal line 66 ... Contact electrode 67 ... Pixel electrode 82 ... Signal line trench equivalent region 101, 114 ... Interlayer insulating film 102 ... Through hole 112 ... Groove 113 ... Wiring 123, 125, 126 ... Inclined surface 127 Inclined surfaces making grooves

Claims (13)

A substrate,
An adhesive layer provided on the substrate so as to have a first groove whose at least one side surface is an inclined surface;
An active element provided on the inclined surface;
A first wiring provided at a bottom of the groove and connected to a first electrode provided on the bottom side of the active element;
An insulating layer provided on the first wiring;
A second electrode provided on the upper surface of the adhesive layer and the insulating layer so as to be in a different direction from the first wiring, and connected to a second electrode provided on the upper side of the groove of the active element; An active matrix substrate comprising: wiring.   2. The active matrix substrate according to claim 1, wherein the height of the upper surface of the adhesive layer and the surface of the insulating layer from the substrate surface are substantially equal.   The active matrix substrate according to claim 1, wherein a support layer is provided between the adhesive layer and the active element. The active element has a third electrode, and a pixel electrode is provided on the upper surface of the adhesive layer,
2. The active matrix substrate according to claim 1, wherein a contact electrode of the pixel electrode is connected to the third electrode provided on the upper side of the groove. The active matrix substrate according to claim 1, wherein a second groove is formed in a region corresponding to the second wiring on the substrate. The active matrix substrate according to claim 4, wherein a recess is formed in a region where the contact electrode and the third electrode are connected on the substrate. The active matrix substrate according to claim 1, wherein an angle formed by the inclined surface and the substrate surface is 20 degrees or more and 85 degrees or less. 4. The active matrix according to claim 3, wherein an end face of the support layer is an inclined end face, and at least one of the first electrode and the second electrode extends to the inclined end face. substrate. 2. The active matrix substrate according to claim 1, wherein wettability between the first wiring and the first electrode is larger than wettability between the first wiring and the adhesive layer. . 2. The active matrix substrate according to claim 1, wherein the wettability between the second wiring and the second electrode is larger than the wettability between the second wiring and the adhesive layer. . The wettability between the first wiring or the second wiring and the adhesive layer is larger than the wettability between the first wiring or the second wiring and the active element. The active matrix substrate according to claim 1. A substrate,
An adhesive layer provided on the substrate and having a plurality of grooves extending in a substantially constant direction and inclined at least one wall surface;
A plurality of active element groups disposed on the inclined wall surface, each having a plurality of electrodes;
A first wiring that is arranged at the bottom of the groove and commonly connects the electrodes located on the bottom side of the groove among the active element groups arranged in the same groove;
An insulating layer provided on the first wiring;
A second wiring that is disposed on the adhesive layer so as to exceed the insulating layer and that is commonly connected to the electrodes located on the upper side of the groove among the electrodes of the active element group disposed in different grooves; An active matrix substrate comprising: Forming an active element having a first electrode and a second electrode on a transfer source substrate;
Forming an adhesive layer provided on the transfer destination substrate so as to have a groove having at least one side surface as an inclined surface;
The active element is transferred from the transfer source substrate onto the inclined surface of the transfer destination substrate so that the first electrode is disposed on the bottom side of the groove and the second electrode is disposed on the upper side of the groove. And a process of
Forming a first wiring connected to the first electrode of the active element on the bottom side of the groove;
Forming an insulating layer on the first wiring;
Connecting the second electrode of the active element, and forming a second wiring on the adhesive layer and the insulating layer so as to be in a different direction from the first wiring. A method for manufacturing an active matrix substrate.

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