JP4744862B2 - Manufacturing method of display device - Google Patents

Description

  The present invention relates to a method for manufacturing a display device.

  When an organic EL element, which is a main part of an organic EL (electroluminescence) display device, is exposed to moisture or oxygen, it easily causes oxidation of the cathode and peeling of the interface between the cathode and the organic layer. Therefore, in the organic EL display device, the organic EL element is sealed, for example, by forming a sealing film on the surface of the array substrate on which the organic EL element is formed.

  By the way, such an organic EL display device is usually manufactured by the following method. First, various elements and wirings are formed on a large insulating substrate. Next, the organic EL element is sealed as described above. Then, a plurality of organic EL display devices are obtained by cleaving this.

  In this method, a protective film with an adhesive may be attached to the sealing film immediately after the sealing film is formed in order to prevent the sealing film from being damaged at the time of cleaving. In this case, a protective film with an adhesive that has been cut in advance to a size corresponding to each organic EL display device may be attached to the insulating substrate before cleaving, but in terms of alignment between the insulating substrate and the protective film, etc. It is considered that it is advantageous to apply a protective film with an adhesive having a size substantially corresponding to the insulating substrate before cleaving and to cut the size into a size corresponding to each organic EL display device at the time of cleaving.

  However, the present inventor has found that the protective film with adhesive attached to the insulating substrate is difficult to cut when making the present invention.

  An object of the present invention is to facilitate the manufacture of a display device that uses a protective film to prevent damage to a sealing film.

According to the first aspect of the present invention, there is provided a step of forming a plurality of element groups each including a plurality of display elements on one main surface of the substrate and spaced apart from each other, and sealing on each of the plurality of element groups. After the step of forming a stop film and the step of forming the sealing film, a plurality of adhesions spaced apart from each other corresponding to the plurality of element groups on the main surface of the substrate on one main surface of the protective film A step of attaching a protective film with an adhesive provided with an adhesive layer so that a gap between the plurality of adhesive layers faces a gap between the plurality of element groups, and the adhesive protective film with the adhesive attached , look including the step of cleaving the substrate along the opposed breaking lines in the gap both gap and said plurality of adhesive layers between the plurality of element groups, after the step of attaching the protective film, the Protective film Method of manufacturing a display device comprising a thing we further including'm a step of cutting along cutting lines of adhesive layers are provided.

According to a second aspect of the present invention, a step of forming a plurality of element groups each including a plurality of display elements on one main surface of the substrate and spaced apart from each other, and sealing on each of the plurality of element groups. After the step of forming a stop film, the step of forming the sealing film, a step of forming a plurality of adhesive layers respectively spaced apart from each other on the plurality of element groups, A process of attaching a protective film to the main surface via the plurality of adhesive layers, and a gap between the plurality of element groups and a gap between the plurality of adhesive layers with the protective film being attached. along opposed breaking line viewed including the step of cleaving said substrate, after the step of attaching the protective film, a step of cutting along the protective film to the cutting line of the plurality of adhesive layers further including What Method of manufacturing a display device comprising is provided.

  According to the present invention, it is easy to manufacture a display device that uses a protective film to prevent damage to the sealing film.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each figure, the same reference numerals are given to components that exhibit the same or similar functions, and duplicate descriptions are omitted.

  FIG. 1 is a cross-sectional view schematically showing an example of an organic EL display device that can be manufactured by the method according to the first aspect of the present invention. In FIG. 1, the organic EL display device 1 is depicted such that its display surface, that is, the front surface or the light emitting surface faces upward, and the back surface faces downward.

  This organic EL display device 1 is a top emission type organic EL display device adopting an active matrix driving method, and includes an array substrate 2 and a sealing film 3 formed on the front surface thereof.

  The array substrate 2 includes an insulating substrate 20 such as a glass substrate. On the main surface on the front side of the insulating substrate 20, a plurality of pixels are arranged in a matrix. Each pixel includes, for example, a drive control element 21 and an organic EL element 22 connected in series between a pair of power supply terminals, and a pixel switch (not shown). The control terminal of the drive control element 21 is connected to a video signal line (not shown) via a pixel switch, and a current having a magnitude corresponding to the video signal supplied from the video signal line is supplied to the organic EL element 22. Output to. The control terminal of the pixel switch is connected to a scanning signal line (not shown), and ON / OFF is controlled by a scanning signal supplied from the scanning signal line. Note that other structures may be employed for these pixels.

On the substrate 20, for example, a SiN _x layer and a SiO _x layer are sequentially stacked as the undercoat layer 23. On the undercoat layer 23, for example, a semiconductor layer 211 which is a polysilicon layer in which a channel and a source / drain are formed, a gate insulating film 212 which can be formed using, for example, TEOS (TetraEthyl OrthoSilicate), and a MoW, for example. The gate electrodes 213 are sequentially stacked, and they constitute a top gate type thin film transistor (hereinafter referred to as TFT). In this example, these TFTs are used as drive control elements 22 and pixel switch TFTs. Further, a scanning signal line (not shown) that can be formed in the same process as the gate electrode 213 is further provided on the gate insulating film 212.

On the gate insulating film 212 and the gate electrode 213, an interlayer insulating film 24 made of, for example, SiO _x formed by a plasma CVD method or the like is provided.

  On the interlayer insulating film 24, a source / drain electrode 25, a reflective layer 28, and a video signal line (not shown) are provided. The source / drain electrode 25 has, for example, a three-layer structure of Mo / Al / Mo, and is electrically connected to the source / drain of the TFT through a contact hole provided in the interlayer insulating film 24. . The video signal line and the reflective layer 28 can be formed in the same process as the source / drain electrode 25.

The source / drain electrodes 25, the reflective layer 28, and the video signal lines are buried with a passivation film 26 made of, for example, SiN _x .

  On the passivation film 26, the first electrodes 221 are juxtaposed apart from each other. The first electrode 221 is electrically connected to the drain electrode 25 through a through hole provided in the passivation film 26. In this example, the first electrode 221 is a light transmissive anode. The first electrode 221 may be light reflective. In this case, the reflective layer 28 is unnecessary.

  A partition insulating layer 27 is further provided on the passivation film 26. The partition insulating layer 27 is provided with a through hole at a position corresponding to the first electrode 221. The partition insulating layer 27 is an organic insulating layer, for example, and can be formed using a photolithography technique.

  An organic layer 222 including a light emitting layer is provided on the first electrode 221 exposed in the through hole of the partition insulating layer 27. The light emitting layer is, for example, a thin film containing a luminescent organic compound whose emission color is red, green, or blue. The organic layer 222 may further include a layer other than the light emitting layer. For example, the organic layer 222 may further include a buffer layer that serves to mediate injection of holes from the first electrode 221 to the light emitting layer. The organic material layer 222 may further include a hole transport layer, a hole blocking layer, an electron transport layer, an electron injection layer, and the like.

  A light transmissive second electrode 223 is provided on the partition insulating layer 27 and the organic layer 222. In this example, the second electrode 223 is a cathode provided continuously in common with each pixel. The second electrode 223 is electrically connected to an electrode wiring formed on the same layer as the video signal line through a contact hole (not shown) provided in the passivation film 26 and the partition insulating layer 27. Yes. Each organic EL element 22 includes the first electrode 221, the organic material layer 222, and the second electrode 223.

On the 1st electrode 221, the sealing film 3 which is a light transmissive insulating layer is formed. The sealing film 3 functions to prevent moisture and the like from entering the organic EL element 22 from the outside and provide a flat surface. The sealing film 3 is obtained, for example, by depositing an inorganic dielectric such as SiN _x on the second electrode 223 using a vapor deposition method such as plasma CVD (Chemical Vapor Deposition). Alternatively, the sealing film 3 can be formed, for example, by applying a resin on the second electrode 223 and curing a coating film obtained thereby.

  A light-transmitting protective film 5 is attached to the sealing film 3 via an adhesive layer 4. As will be described later, the adhesive layer 4 and the protective film 5 are members used mainly for the purpose of protecting the sealing film 3 from damage in the manufacturing process of the organic EL display device 1. Therefore, the adhesive layer 4 and the protective film 5 may be removed from the final product.

  Further, the adhesive layer 4 and the protective film 5 may not be removed from the final product. The protective film 5 can have a role of protecting the sealing film 3 of the completed organic EL display device 1 from damage and a role of preventing moisture and the like from entering the organic EL element 22 from the outside. Furthermore, as the protective film 5, a film having an additional function such as a polarizing film can be used.

This organic EL display device 1 can be manufactured, for example, by the following method.
2 to 6 are cross-sectional views schematically showing a method for manufacturing the organic EL display device according to the first embodiment of the present invention. FIG. 7 is a plan view schematically showing the structure of FIG.

  2 to 6, the organic EL element 22 and the partition insulating layer 27 of each organic EL display device 1 are drawn together as one element group 2227. 2 to 6, only the insulating substrate 20 and the element group 2227 are drawn as members constituting the array substrate 2, and the others are omitted. Furthermore, in FIG. 7, the structure of FIG. 4 seen from the protective film 5 side is drawn.

  In this method, first, an undercoat layer 23 is provided on one main surface, and an insulating substrate 20 having dimensions corresponding to a plurality of organic EL display devices 1 is prepared. Next, on the undercoat layer 23, TFTs used for the drive control element 21 and pixel switch of each organic EL display device 1, various wirings, interlayer insulating film 24, source / drain electrodes 25, reflection layer 28, passivation film 26 and the like are formed.

  Thereafter, the first electrode 221 of each organic EL display device 1 is formed on the passivation film 26. These first electrodes 221 are electrically connected to the drain electrode 25 through through holes provided in the passivation film 26.

  Next, a partition insulating layer 27 of each organic EL display device 1 is formed on the passivation film 26 by using, for example, a photolithography technique. Each partition insulating layer 27 is provided with a through hole at a position corresponding to the first electrode 221. Further, each partition insulating layer 27 is formed to have a size smaller than that of the organic EL display device 1 so that the passivation film 26 and the sealing film 3 can be in contact with each other around the entire periphery.

  Next, an organic layer 222 including a light emitting layer is formed on each first electrode 221. When a low molecular compound is used as the material of the organic material layer 222, the organic material layer 222 is formed by an evaporation method such as a vacuum evaporation method using a mask provided with an opening corresponding to the organic material layer 222, for example. Moreover, when using a high molecular compound as a material of the organic substance layer 222, the organic substance layer 222 is formed by the inkjet method, for example.

  Subsequently, the second electrode 223 of each organic EL display device 1 is formed on the partition insulating layer 27 and the organic layer 222. Each of the second electrodes 223 is formed to have a size smaller than that of the organic EL display device 1 so that the passivation film 26 and the sealing film 3 can be in contact with each other around the entire periphery. The second electrode 223 can adopt a single layer structure or a multilayer structure.

Thereafter, the sealing film 3 of each organic EL display device 1 is formed on the organic EL element 22 and the partition insulating layer 27. Here, as an example, the sealing film 3 is formed by depositing SiN _x using plasma CVD.

  The sealing film 3 is formed to be slightly larger than the partition insulating layer 27 and is in contact with the passivation film 26 over the entire periphery of the partition insulating layer 27. Thereby, the organic EL element 22 and the partition insulating layer 27 are hermetically sealed by the passivation film 26 and the sealing film 3. The structure of FIG. 2 is obtained as described above.

  Next, the protective film with an adhesive shown in FIG. 3 is prepared. This protective film with an adhesive includes a protective film 5 and a plurality of adhesive layers 4 provided on one main surface thereof. As the protective film 5, a film having dimensions corresponding to the plurality of organic EL display devices 1, for example, dimensions corresponding to the insulating substrate 20 before cleaving is used. Each of the adhesive layers 4 has a size substantially equal to that of the sealing film 3, and is disposed at a position corresponding to the sealing film 3 on the protective film 5 so as to be separated from each other.

  Next, the insulating substrate 20 and the protective film with adhesive are aligned so that the adhesive layer 4 is positioned in front of the sealing film 3. Subsequently, as shown in FIGS. 4 and 7, a protective film with an adhesive is attached to the surface of the insulating substrate 20 on which the sealing film 4 is formed.

  Thereafter, as shown in FIGS. 4 and 7, the cleaving line 101 is defined at a position separated from the sealing film 3 and the adhesive layer 4, and the insulating substrate 20 is cleaved along these cleaving lines 101. Thereby, the structure shown in FIG. 5 is obtained.

  The insulating substrate 20 is cleaved by the following method, for example. First, a scribe line is formed along the cutting line 101 on the back surface of the insulating substrate 20 using a scriber. Next, the front and back of the substrate are reversed, and local pressure is applied along the scribe line from the protective film 5 side. Thereby, a crack is expanded in a thickness direction from a scribe line, and various thin films on the insulating substrate 20 are divided.

  Subsequently, as shown in FIG. 5, a cutting line 102 is defined at a position separated from the sealing film 3 and the adhesive layer 4, and the protective film 5 is cut along these cutting lines 102. Thereby, the structure shown in FIG. 6 is obtained. For cutting the protective film 5, for example, cutting or laser processing is used.

  Furthermore, the protective film with an adhesive is peeled from the sealing film 3 as necessary. As described above, the organic EL display device 1 is completed.

  In this method, the adhesive layer 4 is not provided on the entire main surface of the protective film 5, but only on the portion of the main surface of the protective film 5 corresponding to the sealing film 4. In addition, the insulating substrate 20 is cleaved along a cleaving line 101 spaced from the adhesive layer 4. Therefore, the split insulating substrates 20 do not remain connected via the adhesive layer 4.

In this method, the protective film 5 is cut along a cutting line 102 that is separated from the adhesive layer 4. Therefore, the cut protective films 5 do not remain connected via the adhesive layer 4.
And since the blade of a cutting tool does not touch the adhesive bond layer 4, while being able to cut | disconnect the protective film 5 with comparatively small force, the maintenance of a blade becomes easy.

Furthermore, in this method, adhesion of an adhesive to an OLB (Outer Lead Bonding) pad or the like can be prevented without using a mask or the like.
That is, when the method of this aspect is used, the organic EL display device 1 can be easily manufactured.

  Next, the second aspect of the present invention will be described. The second mode is the same as the first mode except that the method for obtaining the structure of FIG. 4 is different.

8 and 9 are cross-sectional views schematically showing a method for manufacturing an organic EL display device according to the second aspect of the present invention.
In this method, first, the structure of FIG. 2 is obtained by the same method as described in the first embodiment.

  Next, as shown in FIG. 8, an adhesive layer 4 is provided on each sealing film 3. These adhesive layers 4 can be formed by applying an adhesive on the sealing film 3 by, for example, a dispenser method or a screen printing method. Alternatively, the adhesive layer 4 provided on release paper or the like may be transferred onto the sealing film 3.

  Next, the protective film 5 shown in FIG. 9 is attached to the sealing film 3 through the adhesive layer 4. Thereby, the structure of FIG. 4 is obtained.

  Thereafter, the steps described in the first embodiment with reference to FIGS. 4 to 7 are performed. As described above, the organic EL display device 1 is completed.

  Thus, the method according to this embodiment is the same as the first embodiment except that the method for obtaining the structure of FIG. 4 is different. Therefore, according to this aspect, the same effect as described in the first aspect can be obtained.

  In the first and second embodiments, when the protective film 5 is peeled from the sealing film 3, the distance from the sealing film 3 or the adhesive layer 4 to the cutting line 102 can grasp the end of the protective film 5 after cutting. You may set so long. Or when leaving the protective film 5 in a final product, you may set the distance from the sealing film 3 or the adhesive bond layer 4 to the cutting line 102 short in order to prevent peeling of the protective film 5. FIG.

  When the protective film 5 is peeled off from the sealing film 3, the entire upper surface of each sealing film 3 may be covered with the adhesive layer 4, or only a part of the upper surface of each sealing film 3 may be covered with the adhesive layer. 4 may be covered. That is, the adhesive layer 4 may be smaller in size than the sealing film 3.

  For example, in the method according to the first aspect, if the size of the adhesive layer 4 is smaller than that of the sealing film 3, compared to the case where the adhesive layer 4 and the sealing film 3 have the same size, The requirement for alignment accuracy between the insulating substrate 20 and the protective film with adhesive is reduced. In the method according to the second aspect, if the adhesive layer 4 is smaller in size than the sealing film 3, compared to the case where the adhesive layer 4 and the sealing film 3 have the same dimensions, The requirement for alignment accuracy between the insulating substrate 20 and the adhesive layer 4 is reduced.

  When the protective film 5 is peeled from the sealing film 3, as the material for the adhesive layer 4, a pressure-sensitive adhesive having a relatively weak adhesive force is usually used. On the other hand, when the protective film 5 is left in the final product, as the material for the adhesive layer 4, an adhesive that is usually cured by heat or light and has a relatively strong adhesive force is used.

  The contact surface of the array substrate 2 with the periphery of the sealing film 3 may not be the surface of the passivation film 26. For example, this contact surface may be the surface of the undercoat layer 23. Typically, the previous contact surface comprises an inorganic insulator.

  In the above aspect, the organic EL display device 1 is a top emission type, but the organic EL display device 1 may be a bottom emission type. For example, the second electrode 223 may be light reflective and the reflective layer 28 may be omitted.

  In the above embodiment, the organic EL display device has been described as an example. However, the present invention is not limited to this, and the present invention is not limited to this. can do. Further, the invention can be applied not only to the display device but also to other fields.

Sectional drawing which shows schematically the example of the organic electroluminescence display which can be manufactured with the method which concerns on the 1st aspect of this invention. Sectional drawing which shows schematically the manufacturing method of the organic electroluminescent display apparatus which concerns on the 1st aspect of this invention. Sectional drawing which shows schematically the manufacturing method of the organic electroluminescent display apparatus which concerns on the 1st aspect of this invention. Sectional drawing which shows schematically the manufacturing method of the organic electroluminescent display apparatus which concerns on the 1st aspect of this invention. Sectional drawing which shows schematically the manufacturing method of the organic electroluminescent display apparatus which concerns on the 1st aspect of this invention. Sectional drawing which shows schematically the manufacturing method of the organic electroluminescent display apparatus which concerns on the 1st aspect of this invention. FIG. 5 is a plan view schematically showing the structure of FIG. 4. Sectional drawing which shows schematically the manufacturing method of the organic electroluminescent display apparatus which concerns on the 2nd aspect of this invention. Sectional drawing which shows schematically the manufacturing method of the organic electroluminescent display apparatus which concerns on the 2nd aspect of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Organic EL display device, 2 ... Array substrate, 3 ... Sealing film, 4 ... Adhesive layer, 5 ... Protective film, 20 ... Insulating substrate, 21 ... Drive control element, 22 ... Organic EL element, 23 ... Undercoat Layers 24... Interlayer insulation film 25. Source / drain electrodes 26. Passivation film 27 27 Partition insulation layer 28. Reflection layer 101 101 Cleaving line 102 102 Cut line 211 211 Semiconductor layer 212 Gate insulation Membrane, 213... Gate electrode, 221... First electrode, 222... Organic layer, 223.

Claims (3)

Forming a plurality of element groups each including a plurality of display elements on one main surface of the substrate and spaced apart from each other;
Forming a sealing film on each of the plurality of element groups;
After the step of forming the sealing film, an adhesive comprising a plurality of adhesive layers spaced apart from each other corresponding to the plurality of element groups on one main surface of the protective film on the main surface of the substrate Attaching the protective film with the adhesive film such that the gap between the plurality of adhesive layers faces the gap between the plurality of element groups;
The still was attached with adhesive protective film, viewing including the step of cleaving the substrate along the gap and breaking line facing both of the gap of the plurality of adhesive layers between the plurality of element groups,
Method for manufacturing a display device, characterized in that after said protective film paste process, but further including do cleaving along the protective film to the cutting line of the plurality of adhesive layers. Forming a plurality of element groups each including a plurality of display elements on one main surface of the substrate and spaced apart from each other;
Forming a sealing film on each of the plurality of element groups;
After the step of forming the sealing film, a step of forming a plurality of adhesive layers respectively spaced apart from each other on the plurality of element groups,
Attaching a protective film to the main surface of the substrate via the plurality of adhesive layers;
The remains stuck a protective film, viewing including the step of cleaving the substrate along the gap and breaking line facing both of the gap of the plurality of adhesive layers between the plurality of element groups,
Method for manufacturing a display device, characterized in that after said protective film paste process, but further including do cleaving along the protective film to the cutting line of the plurality of adhesive layers. The method for manufacturing a display device according to claim 1, wherein laser processing is used for cutting the protective film.

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