JP2006032289A - Manufacturing method of electroluminescent element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve brightness of an EL element by annealing a light-emitting layer so as not to generate ablation. <P>SOLUTION: In the manufacturing method of the EL element successively laminating a first electrode 12, a first insulating layer 13, a light-emitting layer 14 containing a luminous center, a second insulating layer 15 and a second electrode 16 and constituting at least a light-taking-out side with an optically transparent material, after a film is formed on the light-emitting layer 14, and before a film is formed on the second insulating layer 15, the light-emitting layer 14 is annealed by irradiating a laser with a wavelength of 420 nm or less thereon. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing an electroluminescence element (hereinafter referred to as an EL element) used for, for example, a transparent display.

  The EL element utilizes a phenomenon that emits light when an electric field is applied to a phosphor such as zinc sulfide (ZnS), and has attracted attention as a self-luminous flat display.

  FIG. 9 shows a schematic cross-sectional structure of a conventional EL element. The EL element has an optically transparent first electrode 22, a first insulating layer 23, a light emitting layer 24, a second insulating layer 25, and an optically transparent second electrode 26 on a glass substrate 21 that is an insulating substrate. When a predetermined voltage is applied to the intersection of the first electrode 22 and the second electrode 26, the portion emits light.

  As the glass substrate 21, non-alkali glass or low alkali glass is used, and as the first and second electrodes 22 and 26, an ITO film in which tin (Sn) is doped into indium oxide (In2O3) is used, and a light emitting layer As 24, a II-VI group compound semiconductor to which a rare earth element is added is used. Here, the II-VI group compound semiconductor is a compound semiconductor of IIA group and IIB group such as Ca, Sr, Zn and Cd in the old periodic table and VIB group (currently 16 groups) such as O and S. Specifically, as the light emitting layer 24, for example, zinc sulfide is used as a base material and manganese (Mn), terbium (Tb), samarium (Sm) or the like is added as a light emitting center.

In the EL element having such a structure, there is a method of irradiating the light emitting layer 24 with a laser as a method of annealing the light emitting layer 24 in order to improve the light emission luminance (hereinafter simply referred to as luminance) (for example, see Patent Document 1). ).
JP-A-11-224777

  It was found that when the light emitting layer was heat-treated with a laser by the method described in the above publication to produce an EL element, the annealing effect was completely different depending on the wavelength of the laser, the laser irradiation process, and the like. For example, when the heat treatment of the light emitting layer made of ZnS: Mn was attempted with an argon laser of 514.5 nm, no annealing effect was obtained. At this time, when the laser power was increased, laser ablation occurred and the light emitting layer was processed and disappeared. Further, when a heat treatment of the light emitting layer was attempted by heating the first electrode using an infrared laser of 1064 nm, an upper layer film was processed by ablation of the ITO film of the first electrode.

  In view of the above problems, an object of the present invention is to anneal a light emitting layer so as not to cause ablation and to improve luminance of an EL element.

  In order to achieve the above object, according to the first aspect of the present invention, the light emitting layer is irradiated with a laser having a wavelength of 420 nm or less after the light emitting layer is formed and before the second insulating layer is formed. It is characterized by annealing. According to the present invention, by irradiating the light emitting layer with a laser having a wavelength of 420 nm or less, the light emitting layer absorbs laser light and an annealing effect is obtained, so that the crystallinity of the light emitting layer is improved and the luminance of the EL element Can be improved.

  The invention according to claim 2 is characterized in that after the second insulating layer is formed, the light emitting layer is annealed by irradiating the light emitting layer with a laser having a wavelength of 320 nm or more and 420 nm or less. According to this invention, the luminance of the EL element can be improved by irradiating the laser through the second insulating layer, as in the first aspect of the invention. In this case, as described in claim 3, it is preferable to use an ATO film that is a laminated film of alumina and titania as the second insulating layer. Since the ATO film has a high laser transmittance of 320 nm to 420 nm, the use of the ATO film can prevent damage during laser irradiation.

  Further, in the above-described EL device manufacturing method, as in the invention described in claim 4, if at least one of ZnS, SrS, and CaS is included as a base material as a light emitting layer, laser light having a wavelength of 420 nm or less is absorbed. Can be made. In this case, as in the fifth aspect of the present invention, if the thickness of the light emitting layer is 400 nm or less, the light emission efficiency can be greatly changed.

  In the invention described in claim 6, after the light emitting layer is formed, the light emitting layer is removed by using a laser so that the width of the light emitting layer is 200 μm or less, and the light emitting layer is formed by heat generated at that time. It is characterized by annealing. According to the present invention, heat is generated in the step of removing the light emitting layer with a laser, heat is transmitted laterally through the light emitting layer, the light emitting layer can be crystallized, and the luminance of the EL element can be improved. . In this case, it is preferable that the laser wavelength is 600 nm or less as in the invention described in claim 7, and at least one of ZnS, SrS, and CaS is used as the light emitting layer as in the invention described in claim 8. When included as a base material, laser light having a wavelength of 600 nm or less can be absorbed.

(First embodiment)
First, a first embodiment of the present invention will be described. In the first embodiment, after forming the light emitting layer and before forming the second insulating layer, the light emitting layer is irradiated with a laser to perform heat treatment, thereby improving the crystallinity of the light emitting layer. It is intended to increase brightness.

  FIG. 1 is a schematic diagram showing a laser irradiation process of the EL element according to the first embodiment and an EL element manufactured by this process. FIG. 1A is a plan view in the laser irradiation step (only the pattern of the first electrode 12 is shown because each component of the EL element is made of an optically transparent material). FIG. 1B is a cross-sectional view taken along line AA ′ in FIG. 1A, and FIG. 1C is a cross-sectional view of an EL element manufactured through a laser irradiation process.

  The EL element is formed by sequentially laminating the following thin films on a glass substrate 11 that is an insulating substrate. This EL element is manufactured as follows.

  First, an optically transparent ITO film is formed on the glass substrate 1 as the first electrode 12 by sputtering. Further, an Al 2 O 3 / TiO 2 laminated structure film is formed as the first insulating layer 13 by an ALD (Atomic-Layer-Deposition) method. Here, Al2O3 is alumina and TiO2 is titania.

  Specifically, an Al 2 O 3 / TiO 2 laminated structure film is formed as follows. First, as a first step, an Al 2 O 3 layer is formed by an ALD method using aluminum trichloride (AlCl 3) as an aluminum (Al) source gas and water (H 2 O) as an oxygen (O) source gas. In the ALD method, source gases are alternately supplied in order to form a film by one atomic layer. Therefore, in this case, AlCl 3 is introduced into the reaction furnace with argon (Ar) carrier gas for 1 second, and then purge sufficient to exhaust the AlCl 3 gas in the reaction furnace is performed. Next, H2O is similarly introduced into the reaction furnace with Ar carrier gas for 1 second, and then a purge sufficient to exhaust the H2O in the reaction furnace is performed. This cycle is repeated to form an Al2O3 layer having a predetermined thickness.

  As a second step, a titanium oxide layer is formed using titanium tetrachloride (TiCl 4) as the Ti source gas and H 2 O as the oxygen source gas. Specifically, similarly to the first step, TiCl 4 is introduced into the reaction furnace with Ar carrier gas for 1 second, and then purge sufficient to exhaust the TiCl 4 in the reaction furnace is performed. Next, H2O is similarly introduced into the reaction furnace with Ar carrier gas for 1 second, and then a purge sufficient to exhaust the H2O in the reaction furnace is performed. This cycle is repeated to form a titanium oxide layer having a predetermined thickness.

  Then, the first step and the second step described above are repeated to form an Al 2 O 3 / TiO 2 laminated structure film having a predetermined film thickness, which is used as the first insulating layer 13. Specifically, both the Al2O3 layer and the TiO2 layer have a structure in which the thickness per layer is 5 nm and six layers are stacked. The first and last layers of the Al 2 O 3 / TiO 2 laminated structure film may be either an Al 2 O 3 layer or a TiO 2 layer.

  In addition, when a film is formed on the atomic layer order using the ALD method, a film thinner than 0.5 nm does not function as an insulator, and when the film thickness per layer is larger than 20 nm, it depends on the laminated structure. The effect of improving the withstand voltage is reduced. Therefore, the film thickness per layer of the laminated structure film is 0.5 nm to 20 nm, preferably 1 nm to 10 nm.

  Then, a zinc sulfide: manganese (ZnS: Mn) light emitting layer 14 using ZnS as a base material and adding Mn as a light emission center is formed on the first insulating layer 13 by an evaporation method. This state is shown in the plan view of FIG. 1A and the AA ′ cross-sectional view of FIG.

  Next, the light emitting layer 14 is irradiated with a laser having a wavelength of 420 nm or less to anneal the light emitting layer 14. In this case, any laser oscillation source may be used as long as it can irradiate a laser with a wavelength of 420 nm or less, and its harmonics may be used by using an oscillation source with a wavelength of 420 nm or more. . The laser power varies depending on the light emitting layer material and the manner of irradiation, but it is preferable to apply as much power as possible within the range where the constituent elements of the light emitting layer are not processed by ablation.

  Thereafter, the second insulating layer 15 is formed with the same structure and film thickness as the first insulating layer 13, and finally an ITO film is formed as the second electrode 16 in the same manner as the first electrode. This completes the EL element shown in the cross-sectional view of FIG.

  Next, the reason why the wavelength of the laser is set to 420 nm or less will be described with reference to FIG. FIG. 2 is a diagram in which the wavelength dependence of the transmittance of the film constituting the EL element is measured. In FIG. 2, A shows the measurement result when only the first insulating layer 13 is used, and B shows the measurement result when the first insulating layer 13 and the light emitting layer 14 have a two-layer structure. The first insulating layer 13 is an Al 2 O 3 / TiO 2 laminated structure film in which 30 layers each having a thickness of 5 nm are stacked, and the light emitting layer 14 is a ZnS: Mn light emitting layer having a thickness of 900 nm. C is a difference between B and A, and represents a transmittance curve for one layer of the light emitting layer 14 alone.

  When the laser wavelength is 420 nm or less, as shown in the B transmittance curve, the transmittance of the two-layer structure film of the first insulating layer 13 and the light emitting layer 14 decreases as the wavelength becomes shorter. In other words, it shows that the two-layer structure film absorbs laser at a wavelength of 420 nm or less. At this time, as shown in the transmittance curve of C, the light emitting layer 14 can be annealed because only the light emitting layer 14 is absorbed. In addition, although there is a wavelength whose transmittance is slightly reduced at a wavelength of 420 nm or more, it is due to the effect of the interface between the first insulating layer 13 and the light emitting layer 14, and there is almost no annealing effect at that wavelength. In addition, if the film thickness of the 1st insulating layer 13 and the light emitting layer 14 became thin, the absolute value of the transmittance | permeability will become small, but the qualitative tendency did not change.

  Next, selection of the laser beam power will be described. For example, when a laser with a wavelength of 355 nm is used and the light-emitting layer 14 is a ZnS: Mn light-emitting layer with a film thickness of 300 nm, the effect of improving the luminance is confirmed by setting the power of the laser light to 0.01 to 1.0 W. We were able to. In this case, if the power of the laser light is lower than 0.01 W, the crystallinity of the light emitting layer cannot be improved, so that the luminance cannot be improved. If the power is higher than 1.0 W, the light emitting layer is processed by laser ablation. I lost it. In addition, when a laser with a wavelength of 266 nm is used, almost 100% of the light is absorbed by the light emitting layer 14, so the power of the laser light is lower than that when a laser with a wavelength of 355 nm is used. By setting the power to 1 W, the luminance can be improved. The meaning of the lower limit and the upper limit of the numerical values is the same as that when a laser having a wavelength of 355 nm is used. In the above-described example, the power selection range is shown for two types of wavelengths, but generally, if the light absorption rate to the light emitting layer 14 is high, the annealing effect can be obtained with low irradiation power. In addition, when the light emitting layer 14 is formed by vapor deposition as a SrS: Ce or CaS: Eu light emitting layer, a transmittance curve similar to that of ZnS: Mn can be obtained, so the laser wavelength and power can be selected by the same method. do it. In addition, since the optical characteristics of the light emitting layer material with respect to light are determined by the base material, any material such as Mn, Ce, or Eu may be selected as the light emission center material.

  Next, the thickness of the light emitting layer 14 when annealing is described with reference to FIG. FIG. 3 shows data obtained when the EL element having the conventional structure shown in FIG. 9 is annealed for 1 minute by changing the film thickness of the light emitting layer 23 at 700 ° C. in an annealing furnace. The light emitting layer 23 is a ZnS: Mn light emitting layer, and the first insulating layer 23 is the above-described Al 2 O 3 / TiO 2 laminated structure film. The vertical axis in FIG. 3 shows how the luminous efficiency has changed before and after the heat treatment. That is, it shows how many times the light emission efficiency has changed, assuming that the thickness of the light emitting layer is 900 nm. According to FIG. 3, although the annealing effect is firmly obtained when the light emitting layer thickness is 400 nm or less, the effect is reduced when the film thickness is thicker than that, and the annealing effect is almost lost at 900 nm. This data is an experimental result in an annealing furnace, but it is presumed that the same result can be obtained by laser annealing for the following reason. That is, as shown in FIG. 1, when the light emitting layer 14 is formed on the first insulating layer 13, the initial growth stage of the light emitting layer 14 has a crystal structure close to amorphous, and the crystal grains gradually increase as it grows. A film can be formed. The portion with poor crystallinity has low luminous efficiency. When the thickness of the light emitting layer 14 is increased, the crystallinity is sufficiently improved in the vicinity of the interface with the second insulating layer 15 and the effect does not appear even if annealing is performed. Immediately after the film formation, the bad crystallinity can be improved, and the effect becomes a light emission characteristic. In other words, the reason why the luminance is improved is that the crystallinity of the light emitting layer 14 close to the first insulating layer 13 is improved by annealing and does not depend on the means for annealing. It is considered that the same effect as shown in 3 can be obtained.

  Actually, the luminance was measured by irradiating a laser of 266 nm when the film thickness of the light emitting layer 14 was 300 nm and 900 nm. As shown in the experimental results of FIG. Although it was confirmed, the luminance improvement could not be confirmed in the 900 nm sample as described in FIG. FIG. 4 is a graph showing how the voltage-luminance characteristics change depending on the presence or absence of laser annealing after the formation of the light emitting layer 14, and D is a 266 nm laser irradiated at 0.01W. In the case, E indicates a case where laser irradiation is not performed. The first and second insulating layers 13 and 15 have a thickness of 5 nm for both Al 2 O 3 and TiO 2, 6 layers for Al 2 O 3 and 6 layers for TiO 2, and the light emitting layer 14 is a ZnS: Mn film formed by vapor deposition. 300 nm film was formed. The measurement was performed with a rectangular wave having a frame frequency of 480 Hz and a pulse width of 20 μsec. It can be seen from FIG. 4 that the luminance is increased in any voltage region where light emission occurs by laser irradiation.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. In the second embodiment, after the light emitting layer and the second insulating layer are formed, the light emitting layer is irradiated with laser to perform heat treatment, thereby improving the crystallinity of the light emitting layer and increasing the luminance of the EL element. Is.

  FIG. 5 is a schematic diagram showing a laser irradiation process of the EL element according to the second embodiment and the EL element manufactured by this process. FIG. 5A is a plan view in the laser irradiation process (only the pattern of the first electrode 12 is shown because each component of the EL element is made of an optically transparent material). FIG. 5B shows a BB ′ cross-sectional view in FIG. 5A, and the structure of the film is the same as FIG.

  As in the second embodiment, by irradiating the laser after forming the second insulating layer 15, sublimation of the film can be suppressed, so that annealing can be effectively performed. For example, if ZnS is used as the light emitting layer material, it sublimates at 1180 ° C., but if the second insulating layer 15 is present, sublimation does not occur and more efficient annealing can be performed. This is effective even in SrS or CaS having no sublimation point, if the second insulating layer 15 is present, the cooling efficiency of the light emitting layer 14 is lowered. Further, if the light emitting layer 14 is covered with the second insulating layer 15, the same result can be obtained regardless of the atmosphere of the laser irradiation.

  In order to anneal the light emitting layer 14 with a laser, the laser must pass through the second insulating layer 15 and be absorbed by the light emitting layer 14. It can be seen from FIG. 2 that the wavelength region of the laser for this purpose is 320 to 420 nm. In FIG. 2, this is a region where the transmittance of curve A is higher than that of curve B in any wavelength region. When a 266 nm or 308 nm laser having a wavelength shorter than 320 nm, for example, the second insulating layer 15 absorbs almost 100% is irradiated in the state of FIG. 5, if the power is weak, there is no change in the luminance of the EL element. Since the second insulating layer 15 was processed, it was not possible to form an EL element. Further, in the case of a 532 nm laser having a wavelength longer than 420 nm, the light emitting layer 14 did not absorb light, so that the annealing effect could not be obtained. In addition, the luminance could be improved when 355 nm laser light was used. In that case, the power is preferably 0.05 to 0.3 W. This is because there is no annealing effect at 0.05 W or less, and the light emitting layer is processed at 0.3 W or more.

  Further, the film thickness of the light emitting layer 14 is preferably 400 nm or less as in the first embodiment. Furthermore, the material of the second insulating layer 15 is preferably an ATO film that is an Al 2 O 3 / TiO 2 laminated structure film. This is because the film is dense and hardly damaged by laser annealing. Further, even when the crystal structure of the light emitting layer 14 is changed by annealing, the ATO film is not affected. In this case, it is preferable to use an ALD method as a method of manufacturing the second insulating layer 15 because a good dense film is obtained.

  In this second embodiment, it was confirmed by experiment how the voltage-luminance characteristics changed depending on the presence or absence of laser annealing after the second insulating layer 15 was formed, and the result shown in FIG. 6 was obtained. It was. In FIG. 6, F is data when a 355 nm laser is irradiated at 0.15 W, and G is data when no laser is irradiated. The first and second insulating layers 13 and 15 have a thickness of 5 nm for both Al 2 O 3 and TiO 2, 8 layers for Al 2 O 3 and 7 layers for TiO 2, and the light emitting layer 14 is a ZnS: Mn film formed by vapor deposition. 300 nm film was formed. The measurement was performed with a rectangular wave having a frame frequency of 480 Hz and a pulse width of 20 μsec. From FIG. 6, it can be seen that the brightness is increased in any voltage region by laser irradiation.

(Third embodiment)
Next, a third embodiment of the present invention will be described. In the third embodiment, after the light emitting layer is formed, the light emitting layer is removed using a laser, and the light emitting layer is annealed by heat generated at that time.

  FIG. 7 is a schematic view showing a laser irradiation process of the thin film EL element according to the third embodiment and an EL element manufactured by this process. FIG. 7A is a plan view in the laser irradiation process (only the pattern of the first electrode 12 is shown because each component of the EL element is made of an optically transparent material). FIG. 7B is a cross-sectional view at CC ′ in FIG. 7A, and FIG. 7C is a cross-sectional view in a state where the laser irradiation process is completed.

  In the third embodiment, as shown in FIGS. 7A and 7B, a laser is irradiated between the first electrodes 12. At this time, the wavelength of the laser is preferably 600 nm or less. This is because if the wavelength is higher than 600 nm, the first electrode 12 made of an ITO film absorbs laser light well and may be processed. For example, when an SrS: Ce film having a thickness of 900 nm is used for the light emitting layer 14, the effect of improving the luminance can be confirmed when a laser having a wavelength of 355 nm is irradiated with a power of 0.5 to 5 W. In this case, if the power is smaller than 0.5 W, the light emitting layer 14 cannot be removed. If the power is larger than 5 W, the annealing effect has been confirmed, but the first insulating layer 13 is also processed and manufactured. This is not preferable because the probability of occurrence of a defect in the EL element is increased.

  Moreover, as shown in FIG.7 (c), it is preferable that the width | variety b of the light emitting layer 14 which comprises an EL element shall be 200 micrometers or less. When the light emitting layer is removed with a laser, the region where the crystallinity is improved is 100 μm from the boundary where the light emitting layer is removed, so if annealing is performed from both sides, it should be 200 μm or less. The region to be annealed did not change with the light emitting layer material, laser wavelength or power. Therefore, if the light emitting layer material is made of ZnS, SrS, or CaS, the same effect can be obtained.

  In FIG. 7C, the width b is preferably larger than the width of the first electrode 12 from the viewpoint of reliability. If the width b is shorter than that of the first electrode 12, a portion to which a voltage is applied is generated between the first electrode 12 and the second electrode 16 without passing through the light emitting layer 14, and the first and second insulations are generated. This is because an excessive voltage is applied to the films 13 and 15 to easily cause breakdown. Further, if there is no light emitting layer 14 between the first electrodes 12, the luminance of the portion does not change, so the contrast with the adjacent pixels in the EL display is clear and a clear screen can be obtained. This is because, if the adjacent pixels emit light between the first electrodes 12, the light emission may be slightly caused by the photoluminescence effect.

  In this third embodiment, it was confirmed by experiment how the voltage-luminance characteristics changed depending on the presence or absence of laser annealing after the light emitting layer 14 was formed, and the result shown in FIG. 8 was obtained. In FIG. 8, H is data when a 355 nm laser is irradiated at 1.5 W, and I is data when laser is not irradiated. The first and second insulating layers 13 and 15 are films in which 30 layers of both Al 2 O 3 and TiO 2 are stacked with a thickness of 5 nm, and the light-emitting layer 14 is formed by depositing an SrS: Ce film at 1200 nm by an evaporation method. The measurement was performed with a rectangular wave having a frame frequency of 420 Hz and a pulse width of 66 μsec. It can be seen from FIG. 8 that the brightness is increased in any voltage region by laser irradiation.

  In the third embodiment, the thickness of the light emitting layer 14 is not defined. This is because annealing proceeds in the substrate plane, which is different from the first and second embodiments in which annealing is performed in the vertical direction of the substrate.

  In the third embodiment, in the case of an EL element in which RGB three colors are formed of different light emitting layer materials, the patterning of the light emitting layer 14 and the annealing effect can be achieved in one step.

  In the first to third embodiments described above, the case where the first electrode 12 and the second electrode 16 are made of a transparent material has been shown, but the electrode opposite to the light extraction side is a non-transparent metal electrode. Also good. In this case, light is extracted from one side of the light emitting layer 14.

  When a display device is manufactured using the EL elements of the first to third embodiments described above, the display device has high luminance and can be a good-looking display device. Further, if it is not necessary to increase the luminance of the display device, for example, the aperture ratio of the display device can be reduced, so that an inexpensive driving circuit can be manufactured.

It is a figure for demonstrating the manufacturing method of the EL element which concerns on 1st Embodiment of this invention. It is a figure which shows the transmittance | permeability curve of the film | membrane which comprises an EL element. It is a figure which shows the relationship between the light emitting layer film thickness and luminous efficiency when EL element is annealed. It is a figure which shows the voltage-luminance characteristic of the EL element which concerns on 1st Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the EL element which concerns on 2nd Embodiment of this invention. It is a figure which shows the voltage-luminance characteristic of the EL element which concerns on 2nd Embodiment of this invention. It is a figure for demonstrating the manufacturing method of the EL element which concerns on 3rd Embodiment of this invention. It is a figure which shows the voltage-luminance characteristic of the EL element which concerns on 3rd Embodiment of this invention. It is a figure which shows the structure of the conventional EL element.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... EL element, 11 ... Glass substrate as an insulating substrate, 12 ... 1st electrode,
DESCRIPTION OF SYMBOLS 13 ... 1st insulating layer, 14 ... Light emitting layer, 15 ... 2nd insulating layer, 16 ... 2nd electrode.

Claims (8)

An electro in which a first electrode, a first insulating layer, a light emitting layer including a light emission center, a second insulating layer, and a second electrode are sequentially stacked on an insulating substrate, and at least the light extraction side is made of an optically transparent material. In the method for manufacturing a luminescence element,
An electroluminescent device comprising: forming a light emitting layer; and irradiating the light emitting layer with a laser having a wavelength of 420 nm or less before the second insulating layer is formed. Production method. An electro in which a first electrode, a first insulating layer, a light emitting layer including a light emission center, a second insulating layer, and a second electrode are sequentially stacked on an insulating substrate, and at least the light extraction side is made of an optically transparent material. In the method for manufacturing a luminescence element,
A method of manufacturing an electroluminescent element, comprising: forming the second insulating layer; and annealing the light emitting layer by irradiating the light emitting layer with a laser having a wavelength of 320 nm to 420 nm. The method for manufacturing an electroluminescent element according to claim 2, wherein an ATO film that is a laminated film of alumina and titania is used as the second insulating layer. 4. The method of manufacturing an electroluminescent element according to claim 1, wherein the light emitting layer includes at least one of ZnS, SrS, and CaS as a base material. 5. The thickness of the said light emitting layer shall be 400 nm or less, The manufacturing method of the electroluminescent element of Claim 4 characterized by the above-mentioned. An electro in which a first electrode, a first insulating layer, a light emitting layer including a light emission center, a second insulating layer, and a second electrode are sequentially stacked on an insulating substrate, and at least the light extraction side is made of an optically transparent material. In the method for manufacturing a luminescence element,
After forming the light emitting layer, the light emitting layer is removed using a laser so that the width of the light emitting layer is 200 μm or less, and the light emitting layer is annealed with heat generated at that time. A method for manufacturing an electroluminescent element. The method of manufacturing an electroluminescent element according to claim 6, wherein a wavelength of the laser is 600 nm or less. 8. The method of manufacturing an electroluminescent element according to claim 7, wherein the light emitting layer includes at least one of ZnS, SrS, and CaS as a base material.

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