JP2013037820A - Manufacturing method of display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a display device having a laser correction step capable of preventing a metal wiring from short-circuiting without processing or damaging a lower layer of the metal wiring.SOLUTION: A manufacturing method of a display device having a display unit with a plurality of pixels comprises: a first step of preparing a flattening film 13 in which a surface of a drive circuit layer 12 formed on a glass substrate 11 of the display unit is flattened, an upper electrode layer 14P laminated on the flattening film 13, and a patterned resist 20 formed on an upper electrode layer 14P and for separately forming the upper electrode layer 14P as an upper electrode 14 disposed per pixel formation region; a second step of removing a resist residue 20N remaining in a region between adjacent pixel formation regions by irradiating the resist residue 20N with a laser of 266-nm wavelength; and a third step of etching all the pixels using the resist 20 as a mask after the second step is completed.

Description

  The present invention relates to a manufacturing method of a display device, and more particularly to a manufacturing method including a correction step by laser irradiation.

  As an image display device using a current-driven light emitting element, an organic EL display using an organic electroluminescence element (hereinafter referred to as an organic EL element) is known. Since this organic EL display has the advantages of good viewing angle characteristics and low power consumption, it has been attracting attention as a next-generation FPD (Flat Panel Display) candidate.

  Usually, the organic EL elements constituting the pixels are arranged in a matrix. For example, in an active matrix organic EL display, a thin film transistor (TFT) is provided at the intersection of a plurality of scanning lines and a plurality of data lines, and a holding capacitor element (capacitor) and a gate of a driving transistor are provided in the TFT. Is connected. Then, the TFT is turned on through the selected scanning line, a data signal from the data line is input to the driving transistor and the holding capacitor element, and the light emission timing of the organic EL element is controlled by the driving transistor and the holding capacitor element. With this pixel drive circuit configuration, in an active matrix organic EL display, the organic EL element can emit light until the next scanning (selection), so that even if the duty ratio is increased, the luminance of the display is reduced. There is nothing wrong. However, as represented by an active matrix organic EL display, in a manufacturing process that requires fine processing as the driving circuit configuration of the light emitting pixels becomes more complicated and the number of light emitting pixels increases, circuit elements and Electrical problems such as short-circuiting and opening of wiring will occur.

  As a countermeasure against this, there is a method of eliminating a short circuit of a wiring or the like generated in the manufacturing process by YAG laser irradiation. YAG lasers are easier to implement than other lasers and are suitable for such modifications.

  Patent Document 1 discloses a defect correction method for an organic EL panel using a YAG laser. Specifically, in advance, the wavelength of the laser and the output conditions for removing the short defect portion of the electrode without damaging the lower layer of the electrode made of the material corresponding to the electrode material of the organic EL panel are grasped in advance. Keep it. When the short defect portion is removed, the short defect portion is removed by irradiating the YAG laser with the laser wavelength and the output condition corresponding to the grasped electrode material. In addition, when laser irradiation having a wavelength of 355 nm, which is the third harmonic, generates burrs due to thermal effects, the wavelength of 266 nm, which is the fourth harmonic that can be processed mainly due to photolysis reaction, is used. Having laser irradiation is selected. Thereby, it can be corrected without causing thermal damage to the lower layer of the short defect portion.

JP 2004-199956 A

  However, when processing by directly irradiating the metal wiring or the like of the organic EL panel with a YAG laser, the lower layer may be damaged by the irradiation power of the laser. For example, when a planarizing film made of an insulator is present as a lower layer of the metal wiring, the intensity of the irradiation power of the planarizing film is a threshold even when a wavelength of 266 nm, which is the fourth harmonic of the YAG laser, is used. If it exceeds, processing will be started. When processing of the flattening film is started by laser irradiation, the flatness of the processed flattening film is impaired, the stacking accuracy of the organic layer and the upper transparent electrode stacked on the upper layer is lowered, and high yield and high It becomes difficult to realize a fine display.

  The present invention has been made in view of the above problems, and manufacture of a display device having a laser correction process capable of preventing a metal wiring from being short-circuited without processing or damaging the lower layer of the metal wiring. It aims to provide a method.

  In order to solve the above problems, a method for manufacturing a display device according to one embodiment of the present invention is a method for manufacturing a display device including a display portion including a plurality of pixels, which is formed over a substrate included in the display portion. A flattening film for flattening the surface of the formed layer, an electrode layer stacked on the flattening film, and an electrode layer formed on the electrode layer and separated as an electrode arranged for each pixel formation region A laser having a wavelength shorter than a third harmonic wavelength of a YAG laser with respect to the resist remaining in a region between adjacent pixel forming regions, and a first step of preparing a patterned resist for performing A second step of removing the remaining resist by irradiating and a third step of etching all the pixels using the resist as a mask after completion of the second step. And butterflies.

  According to the manufacturing method of the display device of the present invention, the correction that can restore the metal wiring to a good shape without damaging the lower layer of the short defect portion can be performed during the manufacturing process.

1 is a structural cross-sectional view of a display device according to an embodiment of the present invention. It is process sectional drawing and a top view of a pixel with a resist remaining. It is a graph showing the relationship between the laser power of wavelength 266nm, and the processing amount of each film | membrane. It is process sectional drawing of the pixel irradiated with the laser through the slit which has a suitable shape. It is a top view of the pixel irradiated with the laser through the slit. It is process sectional drawing of the pixel irradiated with the laser through the slit which has an inappropriate shape. It is process sectional drawing explaining the manufacturing process of the display apparatus which concerns on embodiment of this invention. It is a top view of the laser irradiation pixel explaining the manufacturing method of the display apparatus which concerns on embodiment of this invention. It is a top view of the laser irradiation pixel explaining the modification 1 of the manufacturing method of the display apparatus which concerns on embodiment of this invention. It is a top view of the laser irradiation pixel explaining the modification 2 of the manufacturing method of the display apparatus which concerns on embodiment of this invention. It is an external view of a thin flat TV incorporating the display device of the present invention.

  A method for manufacturing a display device according to the present invention is a method for manufacturing a display device having a display unit including a plurality of pixels, and planarizing a surface of a layer formed on a substrate included in the display unit. A film, an electrode layer stacked on the planarization film, and a patterned resist formed on the electrode layer for separating and forming the electrode layer as an electrode arranged for each pixel formation region are prepared. By irradiating the resist remaining in the region between the first step and the adjacent pixel formation region with a laser having a wavelength shorter than the wavelength of the third harmonic of the YAG laser, the remaining resist is removed. A second step of removing, and a third step of etching all the pixels using the resist as a mask after completion of the second step.

  According to this aspect, the resist remaining after the patterning collapses is removed by irradiating a laser having a wavelength shorter than the wavelength of the third harmonic of the YAG laser. As a result, heat accumulation in the resist irradiated with the laser and its lower layer is extremely small, and processing is performed exclusively by a photolysis reaction, so that resist receding due to heat and generation of burrs in the periphery of the irradiation are suppressed. Therefore, it is possible to remove the remaining resist and further the underlying electrode layer without damaging the planarizing film which is the lower layer of the electrode layer.

  Further, in one aspect of the method for manufacturing a display device according to the present invention, in the second step, the irradiation power when starting the laser irradiation is the same as that when the surface of the planarizing film is irradiated with the laser. The irradiation power is preferably smaller than the irradiation power at which the planarizing film starts to be processed.

  By utilizing the fact that the processing start power of the planarizing film is higher than that of the electrode layer and the resist, it is possible to remove the remaining resist and the underlying electrode layer without processing the planarizing film.

  In one aspect of the method for manufacturing a display device according to the present invention, in the second step, the remaining resist may be removed by irradiating the laser a plurality of times.

  Laser irradiation having a wavelength shorter than the third harmonic wavelength of the YAG laser generates less heat at the irradiated site and causes the photodecomposition reaction to remove the resist and the electrode layer. Therefore, even if laser irradiation is performed a plurality of times, there is no need to worry about resist receding due to heat or generation of burrs in the periphery of the irradiation. Also, compared to the process of removing the remaining resist by one laser irradiation, the process of removing the remaining resist by multiple laser irradiations has more uniform laser processing variation, and the processing shape, etc. Since the degree of freedom is improved, it is suitable as a manufacturing method and one step of the display device of the present invention.

  In one aspect of the method for manufacturing a display device according to the present invention, the resist pattern inspection is further performed on all pixels of the display device between the first step and the second step. A resist defect detecting step of detecting a pixel in which the resist on the adjacent pixel formation region is not separated by the resist remaining in a region between the adjacent pixel formation regions, and in the second step, The remaining resist may be removed by irradiating the pixel detected in the resist defect detecting step with the laser.

  As a result, the above-described laser irradiation can be performed only on the pixels where the remaining resist exists. Therefore, the manufacturing process can be simplified and the yield can be improved.

  In one aspect of the method for manufacturing a display device according to the present invention, after the third step, a bank patterned in the shape of a bank surrounding the pixel is formed on the surface of the electrode formed by etching. A bank forming step; a light emitting layer forming step for forming a light emitting layer in the bank; an upper electrode forming step for forming an upper electrode on the light emitting layer; and a protective film and a sealing layer on the upper electrode. A sealing layer forming step of sequentially forming the layers.

  Thereby, the manufacturing process of the display apparatus including the correction process by the laser irradiation is realized.

  In one aspect of the method for manufacturing a display device according to the present invention, in the second step, the irradiation width of the laser is narrower than an interval between opposing sides of the adjacent pixel formation region, and the irradiation width. The difference in distance in the laser irradiation direction between one end of the electrode and the side corresponding to the one end is equal to or greater than the film thickness of the electrode layer, and the laser between the other end of the irradiation width and the side corresponding to the other end The difference in distance in the irradiation direction is preferably equal to or greater than the film thickness of the electrode layer.

  Even if the remaining resist and a part of the electrode layer under it are removed by laser irradiation, the distance between the electrode layers etched in the subsequent third step is larger than the distance between the original adjacent pixel formation areas. It can avoid becoming large.

  In one aspect of the method of manufacturing a display device according to the present invention, in the second step, the laser irradiation region includes a part of the remaining resist region, and the laser irradiation in the side direction is performed. The distance between one end and the other end of the region to be processed is longer than the interval between the opposing sides of the adjacent pixel formation region, and the one end and the other end are outside the region sandwiched by the adjacent pixel formation region. It is preferable.

  Thereby, the opposing side surfaces of the opposing electrodes formed after the third step become parallel. Therefore, after that, the bank formed on the region sandwiched between the adjacent pixel formation regions can be formed without breaking the shape, the uniformity of the light emitting layer is not impaired, and the high image quality of the display device is maintained. Is possible.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference numerals throughout all the drawings, and redundant description thereof is omitted. In the following, an image display device composed of an organic EL element having a top emission type anode (anode) on the bottom surface and a cathode (cathode) on the top surface will be described as an example. However, the present invention is not limited to this.

(Embodiment 1)
A manufacturing method of a display device according to the present embodiment is a manufacturing method of a display device having a display unit including a plurality of pixels, and a planarizing film for planarizing the surface of a layer formed on a substrate; A first step of preparing an electrode layer stacked on the planarization film, and a patterned resist formed on the electrode layer for separating and forming the electrode layer as an electrode arranged for each pixel region; A second step of removing the remaining resist by irradiating the resist remaining in the region between the adjacent pixel formation regions with a laser having a wavelength shorter than the wavelength of the third harmonic of the YAG laser; And a third step of etching all the pixels using the resist as a mask after the completion of the second step.

  Thereby, the correction which can restore | restore an electrode layer in a favorable shape, without damaging the lower layer of a short defect part can be implemented in a manufacturing process.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a structural sectional view of a display device according to an embodiment of the present invention. In the figure, a cross-sectional view of an organic EL display panel which is a display unit constituting the display device 10 is depicted. The display device 10 shown in the figure includes a glass substrate 11, a drive circuit layer 12, a planarizing film 13, a lower electrode 14, a bank 15, an EL layer 16, an upper electrode 17, and a protective film 18. And a sealing layer 19.

  The glass substrate 11 is, for example, a substrate made of glass, but may be a flexible substrate made of resin. The glass substrate 11 together with the drive circuit layer 12 constitutes a thin film transistor (TFT) substrate. When the organic EL display panel has a top emission structure, the glass substrate 11 does not need to be transparent, and a non-transparent substrate such as a silicon substrate can be used.

  The drive circuit layer 12 is a layer formed on the glass substrate 11 and includes a drive transistor, a storage capacitor, a switching transistor 21 and the like.

The planarizing film 13 ensures the uniformity of the film thickness of the organic EL element formed in the upper layer by planarizing the unevenness of the surface of the drive circuit layer 12. The planarizing film 13 is an insulating film made of an organic material or an inorganic material, and examples thereof include SiN _x , SiO _x , acrylic, polyimide, and sol-gel, and the film thickness is, for example, 5 μm. Examples of the planarization method include a CMP (Chemical Mechanical Polishing) method.

  When the display device 10 shown in FIG. 1 has, for example, a top emission structure, when a voltage is applied to the EL layer 16, light is generated in the EL layer 16, and the upper electrode 17 that is a transparent cathode and the transparent protective film 18 are transparent. In addition, light is emitted upward through the sealing layer 19. Further, the light generated in the EL layer 16 directed downward is reflected by the lower electrode 14 which is a reflective anode, and the light is emitted upward through the upper electrode 17, the protective film 18 and the sealing layer 19.

  The lower electrode 14 is laminated on the surface of the planarizing film 13 and applies a positive voltage to the EL layer 16 with respect to the upper electrode 17. The lower electrode 14 and the drive transistor included in the drive circuit layer 12 are connected by a via formed in the planarization film 13. The electrode material constituting the lower electrode 14 is, for example, a laminated film (ACL 200 nm / IZO 16 nm) of an amorphous carbon film (ACL) and indium zinc oxide (IZO), or a metal having high reflectivity. Some Al alloys are preferred.

  The EL layer 16 is a light emitting layer, and is formed in a region on the lower electrode 14 and surrounded by the bank 15. The EL layer 16 includes a hole injection layer, a hole transport layer, an organic light emitting layer, an electron injection layer, and the like.

  The hole injection layer is formed on the surface of the lower electrode 14 and has a function of injecting holes into the organic light emitting layer stably or by assisting hole generation. As a result, the driving voltage of the EL layer 16 is lowered, and the lifetime of the device is extended by stabilizing the hole injection. As a material for the hole injection layer, for example, PEDOT (polyethylenedioxythiophene) can be used.

  The hole transport layer is formed on the surface of the hole injection layer, efficiently transports holes injected from the hole injection layer into the organic light emitting layer, and at the interface between the organic light emitting layer and the hole injection layer. It has the function of preventing deactivation of the excitons and blocking the electrons. The hole transport layer is, for example, an organic polymer material having a property of transferring generated holes by intermolecular charge transfer reaction, and examples thereof include triferamine and polyaniline.

  Note that the hole transport layer may be omitted depending on the material of the hole injection layer and the organic light emitting layer which are adjacent layers.

  The organic light emitting layer is formed on the surface of the hole transport layer and has a function of emitting light by generating an excited state by injecting and recombining holes and electrons.

  As the organic light emitting layer, it is preferable to use a light emitting organic material that can be formed by a wet film forming method such as inkjet or spin coating. Thereby, simple and uniform film formation is possible on a large-screen substrate. Although it does not specifically limit as this material, A polymeric organic material is preferable. Features of the polymer organic material include a simple device structure, excellent film reliability, and a low-voltage driven device.

  The electron injection layer is formed on the organic light emitting layer, and has a function of reducing the barrier for electron injection into the organic light emitting layer, lowering the driving voltage of the EL layer 16, and suppressing exciton deactivation. As a result, it is possible to stabilize electron injection and extend the life of the device, to enhance the adhesion with the upper electrode 17 and to improve the uniformity of the light emitting surface and to reduce device defects. The electron injection layer is not particularly limited, but is preferably composed of barium, aluminum, phthalocyanine, lithium fluoride, and a barium-aluminum laminate.

  The bank 15 is patterned in the shape of a bank surrounding the pixel between the patterned lower electrodes 14 and on the surface of the lower electrode 14, and functions as a bank for forming the EL layer 16 in a predetermined region. The material used for the bank 15 may be either an inorganic substance or an organic substance. However, since the organic substance generally has higher water repellency, it can be used more preferably. Examples of such materials include resins such as polyimide and polyacryl. The patterning method of the bank 15 is not particularly limited, but it is preferable to apply a photolithography method using a photosensitive material.

  The upper electrode 17 is stacked on the surface of the electron injection layer, and has a function of injecting electrons into the organic light emitting layer by applying a negative voltage to the EL layer 16 with respect to the lower electrode 14. The upper electrode 17 is not particularly limited, but it is preferable to use a substance and structure having a high transmittance. Thereby, a top emission organic EL element with high luminous efficiency can be realized. The configuration of the upper electrode 17 is not particularly limited, but a metal oxide layer is used. The metal oxide layer is not particularly limited, but a layer made of indium tin oxide (ITO) or IZO is used.

  The protective film 18 is formed on the surface of the upper electrode 17 and has a function of protecting the element from moisture. The protective film 18 is made of, for example, SiN, SiON, or an organic film.

  The sealing layer 19 is formed on the surface of the protective film 18. The sealing layer 19 is made of sealing glass, for example.

  FIG. 2 is a process cross-sectional view and a top view of a pixel having a remaining resist. FIG. 2A is a process cross-sectional view immediately after the patterning of the resist 20 for patterning the lower electrode 14, and is a cross-sectional view of a pixel in which a resist residue exists between the patterned resists 20. . FIG. 2B is a top view of the pixel having the resist residue shown in FIG. In FIG. 2A, the already formed drive circuit layer 12 and glass substrate 11 are not shown.

  When the lower electrode 14 is etched in a subsequent process while the resist residue as shown in FIG. 2 exists, the electrode remains between the lower electrodes to be patterned, and between the lower electrodes. Short defects will occur.

  In the manufacturing method of the display device of the present invention, the resist pattern inspection is performed immediately after the resist 20 for patterning the lower electrode 14 is formed by patterning. As a result, a pixel in which the remaining resist is present is detected, and the remaining resist portion of the detected pixel is irradiated with a laser to erase the remaining resist.

  FIG. 3 is a graph showing the relationship between the laser power at a wavelength of 266 nm and the processing amount of each film. In the figure, the horizontal axis represents the irradiation power of a laser having a wavelength of 266 nm, which is the fourth harmonic of the YAG laser. The vertical axis represents the processing depth of each film when the planarizing film, the resist, and the lower electrode are irradiated with the laser.

From FIG. 3, the lower electrode and the resist are processed according to the laser power as the laser power is increased from zero. On the other hand, the planarizing film is not processed until the laser power is 200 mJ / cm ² , and processing is started from the power.

  By utilizing the processing characteristics of the laser having the wavelength of 266 nm, that is, the processing start power of the planarizing film is larger than that of the lower electrode and the resist, the remaining resist and the lower electrode below the planarizing film It becomes possible to cut without processing.

  Note that in laser irradiation using wavelengths from the fundamental wave to the third harmonic of the YAG laser, resist receding due to heat and burrs on the periphery of the irradiation occur. This is because in any laser irradiation using wavelengths from the fundamental wave to the third harmonic of the YAG laser, any film is processed by the heat generated by the irradiation. On the other hand, in the laser irradiation with the wavelength of 266 nm, heat accumulation in the irradiated film is extremely small, and processing is performed exclusively by a photolysis reaction, so that resist receding due to heat and generation of burrs in peripheral portions of the irradiation are suppressed.

  In the above-described laser irradiation of the resist residue, it is desirable to provide a slit at the site to be irradiated with the laser.

  FIG. 4A is a process cross-sectional view of a pixel irradiated with laser through a slit having an appropriate shape. FIG. 4B is a top view of a pixel irradiated with laser through a slit. FIG. 4A is a cross-sectional view schematically showing a pixel having a resist residue shown in FIG. 2A. The resist residue 20N is formed on the lower electrode 14 together with the patterned resist 20. As shown in FIG. Existing.

  When irradiating the remaining resist 20N with a laser in order to remove the remaining resist 20N, it is desirable to provide a slit 30A having an appropriate shape above the resist layer. The appropriate shape of the slit 30A is that the opening of the slit 30A is smaller than the interval between the resists 20 to be originally patterned, and the laser between the outer periphery of the slits 30A and the end of the resist 20 to be originally patterned. The shape is such that the difference in distance in the irradiation direction (L1 and L2 in FIG. 4A) is equal to or greater than the film thickness t of the lower electrode. In other words, the laser irradiation width is narrower than the interval between the opposing sides of the adjacent pixel formation region, and the difference in the laser irradiation direction distance between one end of the laser irradiation width and the side corresponding to the one end ( L1) is equal to or greater than the film thickness of the lower electrode 14, and the difference (L2) in the laser irradiation direction between the other end of the laser irradiation width and the side corresponding to the other end is equal to or greater than the film thickness of the lower electrode 14. It is. Here, the pixel formation region is a region where the lower electrode 14 is formed.

  As described above, by forming the slit 30A in the appropriate shape, even if the resist residue 20N and a part of the lower electrode 14 located in the lower layer are removed by laser irradiation, the slit 30A is patterned by a subsequent etching process. It can be avoided that the interval between the lower electrodes 14 is larger than the interval between the lower electrodes 14 that should be patterned.

  FIG. 5 is a process cross-sectional view of a pixel irradiated with laser through a slit having an inappropriate shape. The opening of the slit 30B shown in the figure is wider than the interval between the resists 20 to be patterned. When laser irradiation is performed through the slit 30B, when the resist remaining 20N and a part of the lower electrode 14 located in the lower layer are removed by laser irradiation, the interval between the lower electrodes 14 patterned by the subsequent etching process is Due to the side etching of the lower electrode 14, the distance between the lower electrodes 14 to be originally patterned becomes larger.

  Next, the manufacturing process of the display device of the present invention including the above-described correction process by laser irradiation will be described in detail.

  FIG. 6 is a process cross-sectional view illustrating the manufacturing process of the display device according to the embodiment of the present invention.

  First, as shown in FIG. 6A, the drive circuit layer 12 is formed on the glass substrate 11. Thereafter, a planarizing film 13 that also functions as an interlayer insulating layer is formed on the driver circuit layer 12. The planarization film 13 is made of an organic material by, for example, a lithography technique, and the top is planarized.

  Next, as shown in FIG. 6B, the lower electrode layer 14 </ b> P is laminated on the surface of the planarizing film 13. The lower electrode layer 14P is an electrode layer, and is formed, for example, by forming an Al alloy with a film thickness of 500 nm by sputtering.

  Next, as shown in FIG. 6C, a resist film 20P is formed on the surface of the lower electrode layer 14P.

  Next, as shown in FIG. 6D, the resist film 20P is patterned in order to separate and form the lower electrode layer 14P as a lower electrode 14 disposed in each pixel formation region. The resist film 20P is formed by patterning to a thickness of 1 μm using, for example, a lithography technique.

  The step of patterning the planarizing film 13, the lower electrode layer 14P, and the resist film 20P described above corresponds to the first step.

  Next, it is inspected using an image inspection apparatus whether the resist pattern is formed only at a desired location. As a result, as shown in FIG. 6D, due to pattern collapse or the like, pixels where the remaining resist 20N remains in a portion other than the resist 20 that is a desired resist pattern, that is, in a region between adjacent pixel formation regions. Is detected, the pixel is set as a pixel to be corrected by laser irradiation as a pixel in which the resist on the adjacent pixel formation region is not separated. This step corresponds to a resist defect detection step for detecting pixels in which the resist on the adjacent pixel formation region is not separated.

Specifically, as shown in FIG. 6E, the remaining resist 20N is irradiated with a laser using the slit 30A having an appropriate shape shown in FIG. 4A as a mask. Specifically, in order to remove the remaining resist 20N, the resist remaining 20N is irradiated with a laser irradiation power of 20 mJ / cm ² by laser irradiation having a wavelength of 266 nm, which is the fourth harmonic of the YAG laser. At this time, the laser irradiation power is desirably 200 mJ / cm ² or less, which is the processing start power of the planarizing film 13. This step corresponds to a second step of removing the remaining resist 20N by irradiating the remaining resist 20N with the laser.

  Note that the above-described laser irradiation of the remaining resist 20N may be intermittently performed a plurality of times. As described above, the laser irradiation having a wavelength of 266 nm, which is the fourth harmonic of the YAG laser, generates less heat at the irradiated portion, and removes the resist by causing a photolysis reaction. Therefore, even if laser irradiation is performed a plurality of times, there is no need to worry about resist receding due to heat or generation of burrs in the periphery of the irradiation. As a result, compared to the process of removing the resist residue 20N by a single laser irradiation, the process of removing the resist residue 20N by a plurality of laser irradiations can level out variations in laser processing, and the processing shape, etc. Since the degree of freedom of the display device is improved, it is suitable as one step with the manufacturing method of the display device of the present invention.

  As a result, as shown in FIG. 6F, a part of the lower electrode layer 14P existing under the remaining resist 20N is also removed at the same time, but a part of the flattening film 13 as a lower layer is further processed. Not.

  Next, as shown in FIG. 6G, by using the patterned resist 20 as a mask, for example, by etching the lower electrode layer 14P by a wet etching technique excellent in mass productivity, the patterned lower electrode 14 is formed. This step corresponds to a third step of etching all the pixels using the resist 20 as a mask. Thereafter, the etched resist 20 is removed.

  Next, as shown in FIG. 6H, an organic film 15P is laminated on the surface of the lower electrode.

  Next, as shown in FIG. 6I, in order to fill the EL layer 16 on the lower electrode 14 for each pixel, the stacked organic film 15P is formed on the bank surrounding the pixel by using a lithography technique. The bank 15 is formed by patterning into a shape. The patterned bank 15 has a film thickness of 1 μm, for example. This step corresponds to a bank forming step of forming the bank 15 patterned in the shape of a bank surrounding the pixel on the surface of the lower electrode 14 formed by etching.

  Next, as shown in FIG. 6J, the EL layer 16 is filled and formed in the bank 15 using a printing technique or the like. This step corresponds to a light emitting layer forming step.

  Thereafter, the upper electrode 17 is formed on the EL layer 16 by, for example, vapor deposition. This step corresponds to an upper electrode formation step.

  Finally, a protective film 18 and a sealing layer 19 are sequentially formed on the upper electrode 17. This step corresponds to a sealing layer forming step.

  Note that, in the resist pattern inspection by the image inspection apparatus described above, when a pixel in which the remaining resist 20N is present is not detected, the laser irradiation process described in FIGS. 6E and 6F is performed. Instead, the etching process shown in FIG. 6G is performed.

  Through the above manufacturing process, the resist can be corrected to restore the good shape of the lower electrode 14 without damaging the planarizing film 13 which is the lower layer of the short defect portion. In addition, a correction process by multiple times of laser irradiation is possible, whereby the variation in laser processing is leveled and the degree of freedom of the processing shape and the like is improved.

  Note that the laser irradiation range is not limited to the portion where the remaining resist 20N exists, but includes the portion where the remaining resist 20N exists and covers the region within the pixel where the lower electrode layer 14P should be originally removed. It is desirable. Hereinafter, the effect of setting such a laser irradiation range will be described.

  FIG. 7A is a top view of a laser-irradiated pixel for explaining a method for manufacturing a display device according to an embodiment of the present invention. FIG. 7B is a top view of the laser-irradiated pixel for explaining the first modification of the display device manufacturing method according to the embodiment of the present invention. On the other hand, FIG. 7C is a top view of the laser-irradiated pixel for explaining the modification 2 of the method for manufacturing the display device according to the embodiment of the present invention.

  7A and 7B are, from the top, the top view when the laser irradiation is performed using the slit 30A described in FIGS. 4A and 4B as a mask, the shape of the lower electrode 14 after etching, and the lower electrode 14 The top view and sectional drawing of the bank 15 formed on the surface are represented. FIG. 7C is a top view when laser irradiation is performed using the slit 30S as a mask in order from the top, the shape of the lower electrode 14 after etching, and the upper surface of the bank 15 formed on the surface of the lower electrode 14. The figure and sectional drawing are represented.

  When laser irradiation is performed using the slit 30A described in FIG. 7A as a mask, the lower electrode layer 14P after laser irradiation is removed only in the region within the opening of the slit 30A. In this state, when further etching is performed in the next process, side etching from a cross section formed by laser irradiation contributes to the lower electrode layer 14P in the portion opened by the slit 30A, and the lower electrode is not irradiated with laser. A part of the lower electrode 14 recedes as compared with the part where the layer 14P remains. Therefore, by removing the lower electrode layer 14P existing under the resist residue 20N, it is possible to suppress the adjacent lower electrodes 14 from being short-circuited between the adjacent lower electrodes 14. However, the shape of the opposed lower electrode 14 formed after the etching process is not uniform. When the bank 15 is formed on the surface of the lower electrode 14 in this state, the shape of the inclined portion of the bank 15 (the shape difference between the XX ′ section and the YY ′ section in FIG. 7A) is not uniform. Therefore, the uniformity of the EL layer 16 is impaired, and the image quality of the display device is deteriorated. It is also assumed that a region where the end of the bank 15 is not formed on the surface of the lower electrode 14 is generated due to a part of the lower electrode 14 retreating.

  Therefore, by reducing the width of the opening of the slit 30A and adjusting L1 and L2, as shown in FIG. 7B, the shape of the lower electrode 14 is changed to that of the lower electrode layer 14P that was under the remaining resist 20N. A part can be left. Thereby, the possibility that the end of the bank 15 is not formed on the surface of the lower electrode 14 can be reduced.

  However, there remains a problem that the shape of the opposed lower electrode 14 formed after the etching process is not uniform.

  On the other hand, when the laser irradiation is performed using the slit 30S described in FIG. 7C as a mask, the slit 30S is opened over the lower electrode 14, and thus the lower electrode layer 14P after the laser irradiation is an opening of the slit 30S. Has been removed. In this state, when further etching is performed in the next process, in the lower electrode layer 14P opened by the slit 30S, side etching from the cross section formed by laser irradiation contributes and the lower electrode 14 recedes uniformly. To do. Then, the shape of the opposing lower electrode 14 formed after the etching step can be made uniform. When the bank 15 is formed on the surface of the lower electrode 14 in this state, the shape of the inclined portion of the bank 15 (the shape difference between the XX ′ section and the YY ′ section in FIG. 7C) becomes uniform, and the EL The uniformity of the layer 16 is not impaired, and the high image quality of the display device can be maintained.

  That is, the region irradiated with the laser includes a part of the region of the remaining resist 20N, and the distance between one end and the other end of the adjacent laser irradiation region in the adjacent pixel forming region is the adjacent pixel forming region. It is desirable that the laser irradiation region has one end and the other end outside the region sandwiched between adjacent pixel formation regions.

  As mentioned above, although the manufacturing method of the display apparatus of this invention has been demonstrated based on embodiment, the manufacturing method of the display apparatus which concerns on this invention is not limited to the said embodiment. Other embodiments realized by combining arbitrary components in the embodiment and its modifications, and various modifications conceivable by those skilled in the art without departing from the gist of the present invention to the embodiments and their modifications. Modifications obtained by applying the above and various devices incorporating the display device according to the present invention are also included in the present invention.

  Further, for example, the method for manufacturing a display device according to the present invention is used for manufacturing a thin flat TV as shown in FIG. Thereby, a thin flat TV having a display panel in which metal wiring capable of maintaining a good shape is corrected without damaging the lower layer of the short defect portion is realized.

  The display device manufacturing method of the present invention is useful in technical fields such as flat-screen televisions and personal computer displays, which require a large screen and high resolution.

DESCRIPTION OF SYMBOLS 10 Display apparatus 11 Glass substrate 12 Drive circuit layer 13 Flattening film 14 Lower electrode 14P Lower electrode layer 15 Bank 15P Organic film 16 EL layer 17 Upper electrode 18 Protective film 19 Sealing layer 20 Resist 20P Resist film 20N Resist remaining 30A, 30B , 30S slit

Claims (7)

A method of manufacturing a display device having a display unit including a plurality of pixels,
A planarization film for planarizing a surface of a layer formed on the substrate included in the display portion, an electrode layer stacked on the planarization film, and the electrode layer formed on the electrode layer as a pixel formation region A first step of preparing a patterned resist for separate formation as electrodes arranged for each;
A second step of removing the remaining resist by irradiating the resist remaining in the region between the adjacent pixel formation regions with a laser having a wavelength shorter than the wavelength of the third harmonic of the YAG laser. When,
And a third step of etching all the pixels using the resist as a mask after completion of the second step. The irradiation power at the time of starting the irradiation of the laser in the second step is smaller than an irradiation power at which the planarization film starts to be processed when the surface of the planarization film is irradiated with the laser. Method of manufacturing the display device. The method for manufacturing a display device according to claim 1, wherein in the second step, the remaining resist is removed by irradiating the laser a plurality of times. Furthermore, between the first step and the second step,
The resist pattern inspection is performed on all the pixels included in the display device, and the resist on the adjacent pixel formation region is separated by the resist remaining in the region between the adjacent pixel formation regions. A resist defect detection step for detecting non-pixels,
The said 2nd process WHEREIN: The said residual resist is removed by irradiating the said laser with respect to the pixel detected at the said resist defect detection process. Manufacturing method of display device. A bank forming step of forming a bank patterned in the shape of a bank surrounding the pixel on the surface of the electrode formed by etching after the third step;
A light emitting layer forming step of forming a light emitting layer in the bank;
An upper electrode forming step of forming an upper electrode on the light emitting layer;
The method for manufacturing a display device according to claim 4, further comprising: a sealing layer forming step of sequentially forming a protective film and a sealing layer on the upper electrode. In the second step, an irradiation width of the laser is narrower than an interval between opposing sides of the adjacent pixel formation region, and in a laser irradiation direction between one end of the irradiation width and the side corresponding to the one end. The difference in distance is equal to or greater than the film thickness of the electrode layer, and the difference in distance in the laser irradiation direction between the other end of the irradiation width and the side corresponding to the other end is equal to or greater than the film thickness of the electrode layer. The manufacturing method of the display apparatus of any one of Claims 1-5. In the second step, the laser irradiation region includes a part of the remaining resist region,
The distance between one end and the other end of the laser irradiation region in the side direction is longer than the interval between the opposing sides of the adjacent pixel formation region, and the one end and the other end form the adjacent pixel formation. The method for manufacturing a display device according to claim 6, wherein the display device is outside the region sandwiched between the regions.

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