JP5613998B2 - Light emitting device and method for manufacturing light emitting device - Google Patents

Description

The present invention relates to a light emitting device utilizing a variety of light-emitting element, a method of manufacturing及beauty light - emitting device.

  In recent years, various light-emitting devices using light-emitting elements such as organic light emitting diode (hereinafter referred to as “OLED”) elements called organic EL (electroluminescent) elements and light-emitting polymer elements have been proposed. In such a light-emitting device, sealing is performed in order to prevent external light, moisture, or the like from entering a light-emitting element provided on a substrate and deteriorating the light-emitting element. As this sealing technique, a thin film sealing technique in which a light emitting element is covered with an extremely thin inorganic compound film is known.

For example, Patent Document 1 discloses that a first electrode formed on a substrate, a light emitting functional layer formed on the first electrode, a cathode as a second electrode formed on the light emitting functional layer, and a cathode A light emitting device is disclosed that includes a passivation film formed and made of an inorganic material.
JP 2006-332019 A

  Here, when the cathode is made of MgAg, forces that try to bond to each other (force to try to aggregate) act between Ag atoms. Therefore, when the Ag content in the cathode increases, the Ag atoms aggregate together. Uneven portions are generated. In such a case, when the inorganic compound film is formed on the cathode, the load of the inorganic compound film is applied to the cathode. And when the stress with respect to the uneven | corrugated | grooved part on a cathode becomes excessive, there existed a problem that the cathode will be damaged and the electroconductivity of a light emitting element will fall remarkably.

  In addition, when forming a stress relaxation layer for protecting from the load during the formation of an inorganic compound film, depending on the choice of material, there is a possibility of slightly emitting light and reducing contrast when displaying black as a light emitting device. There was a problem that there was.

  In view of such circumstances, an object of the present invention is to solve a decrease in conductivity of a light emitting element in a light emitting device in which thin film sealing is performed without reducing contrast.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 A light emitting device according to the present invention includes a substrate, a light reflecting layer formed on the substrate, a first electrode formed on the light reflecting layer and having transparency, and formed on the first electrode. A light emitting functional layer formed on the light emitting functional layer, a second electrode having transflective properties, and a stress relieving layer formed on the second electrode for relieving stress on the second electrode; A passivation layer made of an inorganic material formed on the stress relaxation layer, the second electrode is made of MgAg, and the atomic ratio of Mg and Ag forming the second electrode is 1: 3 to 1 : 50 range.

  In the present invention, since the atomic ratio of Mg and Ag forming the second electrode is in the range of 1: 3 to 1:50, the Ag content in the second electrode is high, and the Ag atoms are aggregated together. Uneven portions are generated. Further, since the second electrode and the passivation layer formed thereon are made of different materials, physical constants such as a thermal expansion coefficient are different. Therefore, stress is generated between these layers. In particular, when the Ag ratio increases, the stress increases, and this stress causes film peeling, and further causes poor conduction, resulting in poor lighting. However, in the present invention, the second electrode is covered with the stress relaxation layer, and the passivation layer is formed on the stress relaxation layer. Therefore, the load of the passivation layer is dispersed in the stress relaxation layer. Thereby, damage to the second electrode due to stress can be suppressed. Therefore, it can suppress that the electroconductivity of a light emitting element falls.

Application Example 2 In the light emitting device according to the present invention, the light emitting functional layer may include an electron injection layer, and the stress relaxation layer may be made of the same material as the electron injection layer. More specifically, the stress relaxation layer may be made of any one of LiF, Li ₂ O, Liq, MgO, MgF ₂ , CaF ₂ , SrF ₂ , NaF, and WF.

  Application Example 3 In the light emitting device according to the present invention, it is preferable to set the film thickness of the second electrode in the range of 10 nm to 30 nm. This is because if the thickness of the second electrode is thinner than 10 nm, the resistance value of the second electrode is increased, so that sufficient conductivity cannot be obtained. This is because a sufficient amount cannot be secured.

  Application Example 4 A light emitting device according to the present invention includes a substrate, a light reflecting layer formed on the substrate, a first electrode formed on the light reflecting layer and having transparency, and formed on the first electrode. A reduced light emitting functional layer, an electron injecting layer formed on the light emitting functional layer, and a reducing metal material for reducing the electron injecting material formed on the electron injecting layer to form the electron injecting layer A second electrode formed on the reduction layer and having transflective properties, a stress relaxation layer formed on the second electrode for relaxing stress on the second electrode, and the stress relaxation layer And a passivation layer made of an inorganic material, and the second electrode is made of only Ag.

  In the present invention, by using a reducing layer made of a reducing metal material as a base of the second electrode, Ag atoms can be prevented from aggregating into islands, so that the second electrode can be a continuous film. can do. Further, since the second electrode is covered with the stress relaxation layer and the passivation layer is formed on the stress relaxation layer, the damage of the second electrode due to the stress can be suppressed.

  Application Example 5 A light emitting device according to the present invention includes a substrate, a light reflecting layer formed on the substrate, a first electrode formed on the light reflecting layer and having transparency, and formed on the first electrode. A light emitting functional layer formed on the light emitting functional layer, a mixed layer in which an electron injecting material and a reducing metal material for reducing the electron injecting material are mixed, and a semiconductive layer formed on the mixed layer. A second electrode having transmissivity, a stress relaxation layer formed on the second electrode for relaxing stress on the second electrode, and a passivation layer formed on the stress relaxation layer and made of an inorganic material. The second electrode is made of only Ag.

  In the present invention, Ag atoms are aggregated into an island shape by using a mixed layer in which an electron injecting material and a reducing metal material for reducing the electron injecting material are mixed as a base of the second electrode. Since this can be suppressed, the second electrode can be a continuous film. Further, since the second electrode is covered with the stress relaxation layer and the passivation layer is formed on the stress relaxation layer, the damage of the second electrode due to the stress can be suppressed.

Application Example 6 In the light emitting device according to the present invention, the stress relaxation layer may be made of an electron injection material. In this embodiment, the stress relaxation layer can be formed of any one of LiF, Li ₂ O, Liq, MgO, CaF ₂ , SrF ₂ , NaF, and WF. More specifically, the stress relaxation layer can be made of LiF, and the reducing metal material can be made of Al.

  Application Example 7 In the light emitting device according to the present invention, it is preferable to set the film thickness of the second electrode in the range of 10 nm to 30 nm. This is because if the thickness of the second electrode is thinner than 10 nm, the resistance value of the second electrode increases, so that sufficient conductivity cannot be obtained, and if it is thicker than 30 nm, the transparency of the second electrode is reduced. This is because it cannot be secured sufficiently.

  Application Example 8 A method for manufacturing a light emitting device according to the present invention includes a step of forming a light reflecting layer on a substrate, a step of forming a first electrode on the light reflecting layer, and a light emitting functional layer on the first electrode. A step of forming a second electrode on the light emitting functional layer, a step of forming a stress relaxation layer on the second electrode, and a step of forming a passivation layer on the stress relaxation layer, In the step of forming the second electrode on the light emitting functional layer, Mg and Ag are co-evaporated on the light emitting functional layer to form the second electrode, and the deposition rate ratio of Mg and Ag is 1: 3 to 1: It is characterized by being in the range of 50.

  Application Example 9 A light emitting device according to the present invention includes a substrate, a light reflecting layer formed on the substrate, a transparent first electrode formed on the light reflecting layer, and the first electrode. A light emitting functional layer formed on the light emitting functional layer, a second electrode having a transflective property formed on the light emitting functional layer, and a stress for relaxing the stress on the second electrode formed on the second electrode. A stress relaxation layer; and a passivation layer made of an inorganic material formed on the stress relaxation layer. The second electrode is made of an alloy containing 75% or more of Ag in an atomic ratio, and the stress relaxation layer includes: The work function is 4.2 V or more and is made of a material other than Ag.

  With the light-emitting device having such a configuration, the conductivity of the light-emitting element is reduced by suppressing the second electrode from being damaged by stress or the like during formation of the passivation layer while suppressing the decrease in contrast during black display. This can be suppressed. The above “material other than Ag” includes not only metals but also dielectrics.

Application Example 10 In the light emitting device according to the present invention, the stress relaxation layer may be made of any one of Zn, Al, Au, SnO ₂ , ZnO ₂ , and SiO ₂ .

  By forming the stress relaxation layer with such a material, it is possible to sufficiently suppress the decrease in contrast during black display and improve the display quality of the light emitting device.

  Application Example 11 In the light emitting device according to the present invention, the second electrode can be made of an alloy of Mg, Cu, Zn, Pd, Nd, or Al and Ag.

  According to such a configuration, a very thin film layer having a smooth surface can be formed. Therefore, the second electrode having both surface reflectivity and conductivity can be formed, and the display quality of the light emitting device can be improved.

  Application Example 12 In the light-emitting device according to the present invention, it is preferable that the film thickness of the second electrode is set in a range of 0 nm, which is in a range of 10 nm to 30 nm.

  This is because if the thickness of the second electrode is thinner than 10 nm, the resistance value of the second electrode increases, so that sufficient conductivity cannot be obtained, and if it is thicker than 30 nm, the transparency of the second electrode is reduced. This is because it cannot be secured sufficiently.

  Application Example 13 A method for manufacturing a light emitting device according to the present invention includes a step of forming a light reflecting layer on a substrate, a step of forming a transparent first electrode on the light reflecting layer, and the first method. A step of forming a light-emitting functional layer on the electrode, a step of forming a second electrode having transflective properties on the light-emitting functional layer, and relieving stress on the second electrode on the second electrode A step of forming a stress relaxation layer, and a step of forming a passivation layer made of an inorganic material on the stress relaxation layer, wherein the step of forming the stress relaxation layer comprises the steps of: It is a step of forming a stress relaxation layer by a vapor deposition method, and the step of forming the passivation layer is a step of forming the passivation layer by an apparatus including a plasma generator.

  According to this manufacturing method, it is possible to suppress damage to the light emitting functional layer and the second electrode that are the base, and it is possible to obtain a light emitting device with improved reliability.

  Application Example 14 The light emitting device according to the present invention is used in various electronic devices. A typical example of this electronic device is a device that uses a light emitting device as a display device. Such devices include personal computers and mobile phones.

1 is a cross-sectional view of a light emitting device according to a first embodiment of the present invention. The top view of the apparatus for determining whether the sample is damaged. Sectional drawing of the apparatus for determining whether the sample is damaged. The figure which shows the resistance value measured about each when a passivation layer is formed on the sample through the stress relaxation layer which consists of LiF, when a passivation layer is formed directly on the sample. It shows the measurement result when the CaF ₂ is used as the stress relaxation layer. It shows the measurement results when the Li ₂ O is employed as a stress relaxation layer. It shows the measurement result when the MgF ₂ is employed as a stress relaxation layer. Process drawing for demonstrating the manufacturing method of the light-emitting device which concerns on 1st Embodiment. Process drawing for demonstrating the manufacturing method of the light-emitting device which concerns on 1st Embodiment. Sectional drawing of the light-emitting device which concerns on 2nd Embodiment of this invention. Sectional drawing of the light-emitting device which concerns on 3rd Embodiment of this invention. Sectional drawing of the light-emitting device which concerns on 4th Embodiment of this invention. The perspective view which shows the specific form of the electronic device which concerns on this invention. The perspective view which shows the specific form of the electronic device which concerns on this invention. The perspective view which shows the specific form of the electronic device which concerns on this invention. Sectional drawing of the light-emitting device which concerns on 5th Embodiment of this invention. Sectional drawing of the light-emitting device which concerns on 6th Embodiment of this invention. The figure which shows the brightness | luminance at the time of the low current of the light-emitting device which concerns on 5th Embodiment.

Hereinafter, various embodiments according to the present invention will be described with reference to the accompanying drawings. In the drawings, the ratio of dimensions of each part is appropriately changed from the actual one.
<A: First Embodiment>
<A-1: Structure of light emitting device>
FIG. 1 is a cross-sectional view showing a structure of a light emitting device D1 according to the first embodiment of the present invention. As shown in FIG. 1, the light emitting device D <b> 1 has a configuration in which a plurality of light emitting elements U (Ur, Ug, Ub) are arranged on the surface of the first substrate 10. Each light emitting element U is an element that generates light having a wavelength corresponding to one of a plurality of colors (red, green, and blue). In the present embodiment, the light emitting element Ur emits red light, the light emitting element Ug emits green light, and the light emitting element Ub emits blue light. The light emitting device D <b> 1 in this embodiment is a top emission type in which light generated in each light emitting element U travels toward the side opposite to the first substrate 10. Therefore, an opaque plate material such as a ceramic or metal sheet as well as a light-transmitting plate material such as glass can be used as the first substrate 10.

  Although wiring for supplying light to the light emitting element U to emit light is arranged on the first substrate 10, illustration of the wiring is omitted. In addition, although a circuit for supplying power to the light emitting element U is disposed on the first substrate 10, illustration of the circuit is omitted.

  As shown in FIG. 1, partition walls 12 (separators) are formed on the first substrate 10. The partition wall 12 divides the space on the surface of the first substrate 10 for each light emitting element U, and is formed of an insulating transparent material such as acrylic or polyimide.

  Each of the plurality of light emitting elements U includes a light reflecting layer 14, a first electrode 16, a light emitting functional layer 18, and a second electrode 20. As shown in FIG. 1, a plurality of light reflecting layers 14 are formed on the first substrate 10. These light reflecting layers 14 are arranged corresponding to the respective light emitting elements U. Each light reflecting layer 14 is formed of a material having light reflectivity. As this type of material, for example, a simple metal such as aluminum or silver, or an alloy mainly composed of aluminum or silver is preferably employed. In the present embodiment, the trade name “APC” (silver alloy) manufactured by Furuya Metal Co., Ltd. is used as the light reflecting layer 14 and the film thickness thereof is 80 nm.

The first electrode 16 shown in FIG. 1 is an anode, is formed on the light reflecting layer 14, and is surrounded by the partition wall 12. The first electrode 16 is made of a transparent oxide conductive material such as ITO (indium tin oxide), IZO (indium zinc oxide, registered trademark of Idemitsu Kosan Co., Ltd.), or ZnO ₂ . In the present embodiment, the first electrode 16 is made of ITO, and the thickness thereof is different for each emission color of the light emitting element U. The detailed contents will be described later. A transparent layer may be inserted between the reflective layer such as Ag and the first electrode 16. When optimizing the optical path length so as to generate the optimum resonance for the emission wavelength required by the corresponding pixel, the thickness of the first electrode and the transparent layer described above may be optimized. You may change the thickness of the light emitting functional layer mentioned later for every pixel.

  The light emitting functional layer 18 is formed so as to cover each first electrode 16 and the partition 12. That is, the light emitting functional layer 18 is continuous over the plurality of light emitting elements U, and the characteristics of the light emitting functional layer 18 are common to the plurality of light emitting elements U. Although the detailed illustration is omitted, the light emitting functional layer 18 is formed on the hole injection layer formed on the first electrode 16, the hole transport layer formed on the hole injection layer, and the positive transport layer. The light emitting layer includes an electron transport layer formed on the light emitting layer, and an electron injection layer formed on the electron transport layer.

  In the present embodiment, a trade name “HI-406” manufactured by Idemitsu Kosan Co., Ltd. is used as the hole injection layer, and the film thickness is 40 nm. In addition, as a hole transport layer, a trade name “HT-320” manufactured by Idemitsu Kosan Co., Ltd. is used, and its film thickness is 15 nm. In addition, a positive hole injection layer and a positive hole transport layer can also be formed by the single layer which has a function of a positive hole injection layer and a positive hole transport layer.

  The light emitting layer is made of an organic EL material that emits light by combining holes and electrons. In the present embodiment, the organic EL material is a low molecular material and emits white light. A trade name “BH-232” manufactured by Idemitsu Kosan Co., Ltd. is used as a host material of the light emitting layer, and red, green, and blue dopants are mixed in the host material. In this embodiment, the trade name “RD-001” manufactured by Idemitsu Kosan Co., Ltd. is used as the red dopant material, and the trade name “GD-206” manufactured by Idemitsu Kosan Co., Ltd. is used as the green dopant material. As a blue dopant material, trade name “BD-102” manufactured by Idemitsu Kosan Co., Ltd. is used. In the present embodiment, the thickness of the light emitting layer is 65 nm.

  In this embodiment, the electron transport layer is formed of Alq3 (tris 8-quinolinolato aluminum complex), and the film thickness is 10 nm. The electron injection layer is made of LiF (lithium fluoride) and has a thickness of 1 nm. Note that the electron transport layer and the electron injection layer can be formed of a single layer that functions as both the electron injection layer and the electron transport layer.

  The second electrode 20 shown in FIG. 1 is a cathode and is formed so as to cover the light emitting functional layer 18. That is, the second electrode 20 is continuous over the plurality of light emitting elements U. The second electrode 20 functions as a transflective layer having a property of transmitting part of the light reaching the surface and reflecting the other part (that is, transflective), such as magnesium or silver. It is formed from a single metal of the above or an alloy containing magnesium or silver as a main component. In the present embodiment, the second electrode 20 is made of MgAg (magnesium silver alloy). As will be described later, in the present embodiment, Mg and Ag are co-evaporated on the light emitting functional layer 18 to form the second electrode 20.

  The film thickness of the second electrode 20 is preferably set in the range of 10 nm to 30 nm. This is because if the thickness of the second electrode 20 is thinner than 10 nm, the resistance value of the second electrode 20 increases, so that sufficient conductivity cannot be obtained. This is because sufficient permeability cannot be ensured. In the present embodiment, the film thickness of the second electrode 20 is set to 10 nm.

  Although the light emitting functional layer 18 and the second electrode 20 are common to the plurality of light emitting elements U, the individual first electrodes 16 are separated from the other first electrodes 16, so that the individual first electrodes 16 and the second electrodes 16 are separated. When a current flows between the light-emitting layer 20 and the light-emitting functional layer 18, the light-emitting functional layer 18 emits light only at a position overlapping the first electrode 16. That is, the partition 12 partitions the plurality of light emitting elements U.

  In the light emitting device D <b> 1 according to the present embodiment, a resonator structure that resonates light emitted from the light emitting functional layer 18 is formed between the light reflecting layer 14 and the second electrode 20. That is, the light emitted from the light emitting functional layer 18 reciprocates between the light reflecting layer 14 and the second electrode 20, and light having a specific wavelength is strengthened by resonance and transmitted through the second electrode 20 to be observed (see FIG. 1). (Top emission).

  In the light emitting element Ur, the red of the white light emitted from the light emitting functional layer 18 is enhanced, the light emitting element Ug is enhanced in green, and the light emitting element Ug is enhanced in blue, so that the first electrode 16 of each light emitting element U is enhanced. The film thickness is adjusted. More specifically, in the present embodiment, the film thickness of the first electrode 16 in the light emitting element Ur is set to 110 nm, the film thickness of the first electrode 16 in the light emitting element Ug is set to 70 nm, and the light emitting element Ub The film thickness of the first electrode 16 is set to 27 nm.

The stress relaxation layer 22 shown in FIG. 1 is a layer for relaxing stress on the second electrode 20 and is formed so as to cover the second electrode 20. The stress relaxation layer 22 is formed of a material that has light transmittance and moisture resistance and is softer than the second electrode 20 and a passivation layer 24 described later. The stress relaxation layer 22 is formed of the same material as the electron injection layer in the light emitting functional layer 18 and is formed of any one of LiF, LiO ₂ , Liq, MgO, MgF ₂ , CaF ₂ , SrF ₂ , NaF, and WF, for example. Can do. In the present embodiment, the stress relaxation layer 22 is made of LiF and has a thickness of 10 nm.

  As shown in FIG. 1, a passivation layer 24 made of an inorganic material is formed on the second electrode 20 as a protective layer for preventing water and outside air from entering the light emitting element U. The passivation layer 24 is formed from an inorganic material having a low gas permeability such as silicon nitride or silicon oxynitride. In this embodiment, the passivation layer 24 is made of silicon oxynitride and has a thickness of 400 nm.

  As shown in FIG. 1, in the present embodiment, the second substrate 30 is disposed so as to face the plurality of light emitting elements U formed on the first substrate 10. The second substrate 30 is made of a light transmissive material such as glass. A color filter 32 and a light shielding film 34 are formed on the surface of the second substrate 30 facing the first substrate 10. The light shielding film 34 is a light shielding film body in which an opening 36 is formed corresponding to each light emitting element U. A color filter 32 is formed in the opening 36.

  In the present embodiment, a red color filter 32r that selectively transmits red light is formed in the opening 36 corresponding to the light emitting element Ur, and green light is selectively selected in the opening 36 corresponding to the light emitting element Ug. A green color filter 32g to be transmitted is formed, and a blue color filter 32b to selectively transmit blue light is formed in the opening 36 corresponding to the light emitting element Ub.

  The second substrate 30 on which the color filter 32 and the light shielding film 34 are formed is bonded to the first substrate 10 via the sealing layer 26. The sealing layer 26 is formed from a transparent resin material, for example, a curable resin such as an epoxy resin. The above is the structure of the light emitting device D1 of the present embodiment.

  By the way, when the 2nd electrode 20 is formed with MgAg like this embodiment, in order to improve the electroconductivity of the light emitting element U, it is necessary to increase the ratio of Ag excellent in electrical conductivity rather than Mg. Preferably, the Ag atoms have a force to bond with each other (force to agglomerate). Therefore, if the Ag content in the second electrode 20 exceeds a predetermined reference value, the Ag atoms aggregate and become uneven. Parts are generated. In such a case, when the passivation layer 24 is directly formed on the second electrode 20, the load of the passivation layer 24 is applied to the second electrode 20. And when the stress with respect to the uneven part in the 2nd electrode 20 becomes excessive, the 2nd electrode 20 will be damaged and the problem that the electroconductivity of the light emitting element U will fall will arise.

  In the present embodiment, the passivation layer 24 is directly formed on the second electrode 20 when the Ag deposition rate ratio (equal to the atomic ratio according to the analyzer XRF) is lower than Mg: Ag = 1: 3. On the other hand, the second electrode 20 is not damaged. On the other hand, when the Ag atomic ratio is Mg: Ag = 1: 3 or more, the Ag atoms are aggregated to form an uneven portion. It has been found that the second electrode 20 is broken when 24 is formed directly. From the above knowledge, in this embodiment, the deposition rate ratio of Mg and Ag forming the second electrode 20 (equal to the atomic ratio according to the analyzer XRF) is set in the range of 1: 3 to 1:50. In addition, a configuration is adopted in which the second electrode 20 is covered with the stress relaxation layer 22 and the passivation layer 24 is formed on the stress relaxation layer 22.

  In this embodiment, since the atomic ratio of Ag is set to Mg: Ag = 1: 3 or more, the second electrode 20 has an uneven portion, but the second electrode 20 has the stress relaxation layer 22. Since the passivation layer 24 is formed on the stress relaxation layer 22, the load of the passivation layer 24 is dispersed in the stress relaxation layer 22. Thereby, since the damage of the 2nd electrode 20 by stress can be suppressed, there exists an advantage that the electroconductivity of the light emitting element U can be made into a favorable state.

  FIG. 2 shows an outline of an apparatus 40 for determining whether or not the sample of the second electrode 20 manufactured by setting the atomic ratio of Mg and Ag to 1: 9 is damaged. It is a top view. 3 is a cross-sectional view taken along line AA shown in FIG.

  The apparatus 40 includes a test substrate 42, four test electrodes 44 (44 a to 44 d) formed on the test substrate 42, and a grid-like partition wall 46 for separating the four test electrodes 44, Of the region on the test electrode 44, the region is divided by a partition wall 46 (region surrounded by the opening B shown in FIG. 2) and a test metal thin film 48 formed on the partition wall 46. The test metal thin film 48 is a sample of the second electrode 20 manufactured by setting the atomic ratio of Mg and Ag to 1: 9.

  In the present embodiment, a method for determining whether or not a sample is damaged will be described with reference to FIG. By bringing a tester terminal into contact with each of the test electrodes 44a and 44b adjacent to each other, a current path (or test) from the test electrode 44a to the test electrode 44b through the sample (the test metal thin film 48) The resistance value of the current path from the electrode 44b to the test electrode 44a through the sample is measured. When the sample is damaged, the resistance value measured by the tester shows a remarkably large value, and therefore it can be determined whether or not the sample is damaged based on the resistance value.

  In FIG. 4, when the passivation layer 24 is directly formed on the sample (the test metal thin film 48), the stress relaxation layer 22 having a thickness of 10 nm is formed on the sample, and the passivation layer 22 is formed on the stress relaxation layer 22. When the layer 24 is formed, the stress relaxation layer 22 having a thickness of 25 nm is formed on the sample, and when the passivation layer 24 is formed on the stress relaxation layer 22, the film thickness of 50 nm is formed on the sample. It is a figure which shows the resistance value measured by the tester about each when the stress relaxation layer 22 is formed and the passivation layer 24 is formed on the said stress relaxation layer 22. FIG. In any case of FIG. 4, the film thickness of the sample is set to 13 nm, and LiF is adopted as the material of the stress relaxation layer 22.

  As shown in FIG. 4, when the passivation layer 24 is directly formed on the sample, the resistance value is extremely high (about 10 MΩ), which indicates that the sample is damaged. On the other hand, when the stress relaxation layer 22 made of LiF is formed on the sample and the passivation layer 24 is formed on the stress relaxation layer 22, the resistance value is 25 nm when the thickness of the stress relaxation layer 22 is 10 nm. In the case of 50 nm, almost the same value is shown in the case of 50 nm, and since all values are around 5Ω, it can be seen that the sample is not damaged.

FIG. 5 is a diagram showing resistance values in the case where CaF ₂ is adopted as the material of the stress relaxation layer 22 instead of LiF and the film thickness is 10 nm, 25 nm, and 50 nm. In any case shown in FIG. 5, the measurement is performed after the stress relaxation layer 22 is formed on the sample and the passivation layer 24 is formed on the stress relaxation layer 22. As shown in FIG. 5, when the CaF ₂ film thickness is 10 nm, 25 nm, and 50 nm, the resistance values in the respective cases show substantially the same values, and all have values of about 5Ω.

FIG. 6 is a diagram showing resistance values in the case where Li ₂ O is employed as the material of the stress relaxation layer 22 and the film thickness is 10 nm, 25 nm, and 50 nm. In any case shown in FIG. 6, the measurement is performed after the stress relaxation layer 22 is formed on the sample and the passivation layer 24 is formed on the stress relaxation layer 22. Also in FIG. 6, when the Li ₂ O film thickness is 10 nm, 25 nm, and 50 nm, the resistance values in the respective cases show substantially the same values, and all have values of around 5Ω.

FIG. 7 is a diagram showing resistance values in cases where MgF ₂ is employed as the material of the stress relaxation layer 22 and the film thickness is 10 nm, 25 nm, and 50 nm. In any case shown in FIG. 7, the measurement is performed after the stress relaxation layer 22 is formed on the sample and the passivation layer 24 is formed on the stress relaxation layer 22. Also in FIG. 7, when the film thickness of MgF ₂ is 10 nm, 25 nm, and 50 nm, the resistance values in the respective cases show substantially the same values, and all have values of around 5Ω.

  From the above, it can be seen that by adopting a configuration in which the stress relaxation layer 22 is formed on the sample and the passivation layer 24 is formed on the stress relaxation layer 22, damage to the sample due to stress is suppressed.

<A-2: Manufacturing method of light emitting device>
Next, referring to FIG. 8 and FIG. 9, any one of the light emitting device D1 of the present embodiment, the light emitting device D5 of the fifth embodiment described later, and the light emitting device D6 of the sixth embodiment described later. A method for manufacturing the light emitting device will be described.

  First, a plurality of light reflecting layers 14 are formed in a matrix on the first substrate 10 by a known method (step P1 in FIG. 8), and the first electrode 16 is formed on the light reflecting layer 14 (step in FIG. 8). P2). Subsequently, the partition walls 12 are formed in a lattice shape (step P3 in FIG. 8). For example, a photosensitive material can be mixed with acrylic or polyimide used as the material of the partition wall 12, and the partition wall 12 can be patterned by exposure using a photolithography technique.

  Next, the light emitting functional layer 18 is formed so as to cover the partition wall 12 and the first electrode 16 by a known method such as vapor deposition (process P4 in FIG. 8). Further, the second electrode 20 is formed on the light emitting functional layer 18 (process P5 in FIG. 8).

  In the process P5, Mg and Ag are co-evaporated on the light emitting functional layer 18 to form the second electrode 20. As described above, in this embodiment, the deposition rate ratio of Mg and Ag (equal to the number ratio of atoms according to the analyzer XRF) is set in the range of 1: 3 to 1:50.

  Next, the stress relaxation layer 22 is formed on the second electrode 20 (step P6 in FIG. 9), and the passivation layer 24 is formed on the stress relaxation layer 22 (step P7 in FIG. 9). Here, the stress relaxation layer 22 is preferably formed by a vapor deposition method (heat vapor deposition method). According to this method, it is possible to suppress damage to the light emitting functional layer 18 and the second electrode 20 serving as the base. The passivation layer 24 is preferably formed by an apparatus including a plasma generator. According to this method, a dense film layer can be formed, and the reliability of the light emitting element U and the light emitting device D1 (D5, D6) can be improved.

  Furthermore, after the sealing layer 26 is applied on the passivation layer 24, the second substrate 30 on which the color filter 32 and the light shielding film 34 are formed is bonded (step P8 in FIG. 9). The above is the manufacturing method of the light emitting device D1 of the present embodiment.

<B: Second Embodiment>
FIG. 10 is a cross-sectional view showing the structure of a light emitting device D2 according to the second embodiment of the present invention. In each of the embodiments described above, the light emitting functional layer 18 is common to all the light emitting elements U. However, in the second embodiment, the light emitting functional layer 18 is formed separately for each light emission color of the light emitting element U.

As shown in FIG. 10, each light emitting functional layer 18 (18r, 18g, 18b) has the first electrode 16.
A hole injection layer 41 formed thereon, a hole transport layer 43 formed on the hole injection layer 41, and a light emitting layer 45 (45r, 45g, 45b) formed on the hole transport layer 43; And an electron transport layer 47 formed on the light emitting layer 45 and an electron injection layer 49 formed on the electron transport layer 47. The light emitting functional layer 18r of the light emitting element Ur includes a light emitting layer 45r formed of an organic EL material that generates light in the R (red) wavelength region, and the light emitting functional layer 18g of the light emitting element Ug is in the G (green) wavelength region. The light emitting functional layer 18b of the light emitting element Ub includes a light emitting layer 45b formed of an organic EL material that generates light in the B (blue) wavelength region. Including. As shown in FIG. 10, each light emitting functional layer 18 is formed for each area of the light emitting element U divided by the partition 12, and is not connected to the adjacent light emitting functional layer 18.

  In FIG. 10, the film thickness of the hole transport layer 43 in each light emitting element U is adjusted so that red is enhanced in the light emitting element Ur, green is enhanced in the light emitting element Ug, and blue is enhanced in the light emitting element Ub. The In the second embodiment, the emission color of each light emitting element U is enhanced by adjusting the film thickness of the hole transport layer 43 in each light emitting element U. However, the present invention is not limited to this, and the first electrode 16 is not limited thereto. The light emission color of each light emitting element U can be enhanced by adjusting the film thickness of any of the hole injection layer 41, the light emitting layer 45, the electron transport layer 47, and the electron injection layer 49.

  Also in the second embodiment, the vapor deposition rate ratio (atomic number ratio) of Mg and Ag forming the second electrode 20 is set in the range of 1: 3 to 1:50 as in the above-described embodiments. The second electrode 20 is covered with the stress relaxation layer 22, and the passivation layer 24 is formed on the stress relaxation layer 22. Therefore, the load of the passivation layer 24 is dispersed in the stress relaxation layer 22. Thereby, damage to the second electrode 20 due to stress can be suppressed.

<C: Third Embodiment>
FIG. 11 is a cross-sectional view showing a structure of a light emitting device D3 according to the third embodiment of the present invention. Although the detailed illustration is omitted, the light emitting functional layer 18 is formed on the hole injection layer formed on the first electrode 16, the hole transport layer formed on the hole injection layer, and the positive transport layer. A light emitting layer formed on the light emitting layer, and an electron transporting layer formed on the light emitting layer.

  As shown in FIG. 11, an electron injection layer 49 for improving the efficiency of electron injection into the light emitting functional layer 18 is formed on the light emitting functional layer 18. In the third embodiment, the electron injection layer 49 is made of LiF and has a thickness of 1 nm.

  As shown in FIG. 11, a reduction layer 51 made of a reducing metal material for reducing the electron injection material forming the electron injection layer 49 is formed on the electron injection layer 49. In the third embodiment, the reduction layer 51 is made of Al and has a thickness of 2 nm.

  As shown in FIG. 11, the second electrode 20 is formed on the reduction layer 51. In the third embodiment, the second electrode 20 is made of only Ag. The film thickness of the second electrode 20 is desirably in the range of 10 nm to 20 nm as in the first embodiment described above. In the third embodiment, the film thickness of the second electrode 20 is set to 13 nm. The above points are different from the configuration of the first embodiment described above. Since the other configuration is the same as the configuration of the first embodiment described above, the description of the overlapping portions is omitted.

  In the third embodiment, by using a reducing metal material (Al in the third embodiment) forming the reduction layer 51 as a base of the second electrode 20, Ag atoms forming the second electrode 20 aggregate together. It is possible to suppress island formation (film tearing). Thereby, the 2nd electrode 20 can be used as a continuous film | membrane. However, aggregation of Ag atoms cannot be suppressed completely, and an uneven portion is generated in the second electrode 20 in the third embodiment. Further, since the second electrode 20 and the passivation layer 24 formed thereon are made of different materials, physical constants such as a thermal expansion coefficient are different. Therefore, stress is generated between these layers. In particular, when the Ag ratio increases, the stress increases, causing a problem that the second electrode 20 is peeled off and the conductivity of the light emitting element U is lowered.

  In the third embodiment, since the second electrode 20 is covered with the stress relaxation layer 22 and the passivation layer 24 is formed on the stress relaxation layer 22 as in the first embodiment described above, the load of the passivation layer 24 is Is dispersed in the stress relaxation layer 22. Thereby, damage to the second electrode 20 due to stress can be suppressed.

  In the third embodiment, the configuration in which the light emitting functional layer 18 is common to all the light emitting elements U is illustrated, but the light emitting functional layer 18 emits light from the light emitting element U as in the second embodiment described above. A configuration formed separately for each color may be employed.

<D: Fourth Embodiment>
FIG. 12 is a cross-sectional view showing a structure of a light emitting device D4 according to the fourth embodiment of the present invention. In the fourth embodiment, a mixed layer 53 in which an electron injecting material and a reducing metal material for reducing the electron injecting material are mixed is formed on the light emitting functional layer 18, and the second electrode is formed on the mixed layer 53. 20 is different from the configuration of the third embodiment described above. Since other configurations are the same as those of the third embodiment described above, description of overlapping portions is omitted. In the fourth embodiment, LiF is adopted as the electron injection material, and Al is adopted as the reducing metal material.

  As in the fourth embodiment, the Ag atoms forming the second electrode 20 are also aggregated by using the mixed layer 53 in which the electron injection material and the reducing metal material are mixed as the base of the second electrode 20. It is possible to suppress island formation (film tearing). Further, since the second electrode 20 and the passivation layer 24 formed thereon are made of different materials, physical coefficients such as a thermal expansion coefficient are different. Therefore, stress is generated between these layers. In particular, when the Ag ratio increases, the stress increases and the second electrode 20 peels off.

  Also in the fourth embodiment, since the second electrode 20 is covered with the stress relaxation layer 22 and the passivation layer 24 is formed on the stress relaxation layer 22 as in the third embodiment described above, the load on the passivation layer 24 is Is dispersed in the stress relaxation layer 22. Thereby, damage to the second electrode 20 due to stress can be suppressed.

  In the fourth embodiment, the configuration in which the light emitting functional layer 18 is common to all the light emitting elements U is illustrated, but the light emitting functional layer 18 emits light from the light emitting element U as in the second embodiment described above. A configuration formed separately for each color may be employed.

<E: Fifth Embodiment>
FIG. 16 is a cross-sectional view showing a structure of a light emitting device D5 according to the fifth embodiment of the present invention. The light emitting device D5 according to the present embodiment has a configuration similar to the light emitting device D1 according to the first embodiment described above. That is, the light emitting device D5 is a top emission type light emitting device in which three types of light emitting elements U (Ur, Ug, Ub) are arranged on the surface of the first substrate 10. The light emitting element Ur emits red light, the light emitting element Ug emits green light, and the light emitting element Ub emits blue light. The light emitting element U has a structure in which the light reflecting layer 14, the first electrode 16, the light emitting functional layer 18, and the second electrode 20 are laminated on the first substrate 10.

  The three types of light emitting elements U (Ur, Ug, Ub) have a common light emitting functional layer 18. The color of the emitted light is determined by the enhancement effect of light in a specific wavelength range due to resonance between the light reflection layer 14 and the second electrode 20, and the coloring effect by the color filter 32 (32r, 32g, 32b). ing. Other configurations are substantially the same as those of the light emitting device D1 according to the first embodiment. Therefore, description of such common elements is omitted.

  The light emitting device D5 according to this embodiment has a slightly different sealing layer from the light emitting device D (D1, D2, D3, D4) according to each of the above embodiments. The sealing layer in each of the above-described embodiments includes the organic buffer layer 64, the gas barrier layer 66, and the transparent adhesive layer 68. However, this configuration can also be applied to the light-emitting devices D (D1, D2, D3, D4) according to the above-described embodiments.

  Similar to the passivation layer 24, the gas barrier layer 66 is a layer that suppresses infiltration of moisture and the like from the outside, and is made of silicon oxide having a layer thickness of 200 nm to 400 nm. The organic buffer layer 64 is made of epoxy resin (or acrylic resin or the like) and flattens the level difference caused by the partition wall 12 or the like. The transparent adhesive layer 68 is made of an epoxy resin, and the first substrate 10 and the second substrate 30 are bonded together.

  In addition, an overcoat layer 35 that protects the color filter is disposed on the surface of the second substrate 30 of the light emitting device D5 according to the present embodiment on the color filter 32 side, and a circularly polarizing plate 70 is disposed on the opposite surface. Is arranged. The circularly polarizing plate 70 uses the property that the rotation direction of polarized light is reversed, and suppresses the deterioration of display quality due to reflection of the light reflecting layer 14 and the like. Both of these elements are also applicable to the light emitting device D (D1, D2, D3, D4) according to each of the above-described embodiments.

In the light emitting device D5 according to the present embodiment, the electron injection layer that is the uppermost layer of the light emitting functional layer 18 is formed of LiF, and the layer thickness is 1 nm. As a material for forming the electron injection layer, in addition to LiF, Li ₂ O, MgO, CaF ₂ or the like formed to have a layer thickness of 0.5 nm to 2 nm, preferably 1 nm can be used. Furthermore, Liq (lithium quinolinol) can be laminated to 1 nm to 20 nm to serve as the electron transport layer.

  Further, the material for forming the second electrode 20 of the light emitting device D5 according to the present embodiment uses MgAg (magnesium silver alloy) as in the light emitting device D1 according to the first embodiment. The mixing ratio is MG: Ag = 1: 20, and the layer thickness is 10 nm. Ag is highly reflective and conductive, and is suitable as a material for forming the second electrode. However, when a thin film having a layer thickness of 30 nm or less is formed by a vapor deposition method, the film quality is not flat but rough, so that reflectivity and conductivity are lowered. When other metals are mixed and used, the film quality can be flattened and at the same time the conductivity can be improved.

  In addition, the formation material of the 2nd electrode 20 can also use the alloy of metals other than Mg, and Ag, and the laminated body of this alloy. Specifically, an alloy of any one of Cu, Zn, Pd, Nd, and Al and Ag can be used. And the laminated body of this alloy, for example, the thing which laminated | stacked AgCu and AgPd can also be used.

In the light emitting device D5 according to the present embodiment, the material for forming the stress relaxation layer 22 is greatly different from that of the light emitting device D1 (and D2, D3, D4). That is, the stress relaxation layer 22 of the light emitting device D5 according to the present embodiment is made of a metal or dielectric such as Zn, Al, Au, SnO ₂ , ZnO ₂ , SiO ₂ or the like whose work function excluding Ag is 4.2 V or more. Is formed. The reason is shown below.

The purpose of forming the stress relaxation layer 22 is to relieve the stress applied to the second electrode 20 when the passivation layer 24 is formed. Another object of the present invention is to suppress deterioration (blackening due to oxidation, opacification) of Ag contained in the second electrode 20 due to O ₂ plasma performed before forming the passivation layer 24. Therefore, in the light emitting devices (D1, D2, D3, D4) according to the first to fourth embodiments described above, the material for forming the stress relaxation layer 22 is selected on the condition that it is softer than the second electrode 20 and the passivation layer 24. Has been. Of course, light transmission and moisture resistance are also required.

  However, in a subsequent experiment, when the stress relaxation layer 22 is formed of a material having a work function of less than 4.2 eV (electron volts), the light emitting element U emits light slightly when displaying black as the light emitting device D. It has been found that the contrast can be reduced. Further experiments have revealed that the above-described light emission (during black display) can be suppressed by forming the stress relaxation layer 22 with a material having a work function of 4.2 eV (electron volts) or more. In the light emitting device D5 according to the present embodiment, Zn (zinc) is selected as a material for forming the stress relaxation layer 22 based on the experimental result. Specifically, the stress relaxation layer 22 is formed by depositing Zn having a layer thickness of 3 nm by an evaporation method. By selecting the forming material, the light emitting device D5 according to the present embodiment has conductivity and transparency similar to the light emitting devices (D1, D2, D3, D4) according to the first to fourth embodiments described above. While obtaining the favorable 2nd electrode 20, the light emission at the time of black display is reduced, and the contrast is improved.

FIG. 18 is a diagram showing light emission during black display of the light emitting device D5 according to the present embodiment, that is, luminance at low current. Specifically, the vertical axis represents the luminance (Cd / m ² ) when a current of 0.00033 mA / cm ² is applied. Such luminance at low current is hereinafter simply referred to as “luminance”. The lower the luminance, the more the contrast of the light emitting device can be improved. Moreover, the stress relaxation layer 22 for comparison is formed of a material other than Zn, and the other components show the same luminance of the light emitting device as that of the light emitting device D5. The horizontal axis indicates the material for forming each stress relaxation layer 22 and the layer thickness. As shown in the drawing, the measurement result of the light emitting device D5 according to the present embodiment, that is, the measurement result when the stress relaxation layer 22 is formed of Zn having a layer thickness of 3 nm is described at the right end.

  The electron injection layer and the second electrode 20 of each light-emitting device used for the luminance measurement described above are LiF 1 nm and the second electrode 20 is MgAg (1) except for the “standard” light-emitting device at the left end described as a reference. : 20). The electron injection layer of the “standard” light emitting device is LiF with a layer thickness of 1 nm, and the second electrode 20 is MgAg (10: 1). The combination of the electron injection layer and the second electrode 20 in such a (standard light emitting device) is not suitable for a top emission type light emitting device because of low light extraction efficiency but low luminance. Therefore, in the light emitting device D (D1, D2, D3, D4, D5) of each embodiment of the present invention, the second electrode 20 is formed of Ag alone or a material mainly composed of Ag.

The luminance of the light emitting device D5 according to this embodiment is 0.00033 Cd / m ² . The luminance of the light emitting device in which the stress relaxation layer 22 is formed of SnO ₂ (tin oxide) having a thickness of 5 nm is 0.00032 Cd / m ² and is further excellent. On the other hand, the luminance of the light emitting device in which the stress relaxation layer 22 is made of Al having a thickness of 3 nm is 0.00312 Cd / m ^2, which is about 10 times the value when Zn or SnO ₂ is used. Here, looking at the work function of each of the above materials, Zn is 4.9 eV, SnO ₂ is 5.0 eV, and Al is 4.2 eV. Therefore, it can be seen that the stress relaxation layer 22 is preferably formed of a material having a work function of 4.2 eV or more.

The brightness when LiF with a layer thickness of 5 nm is used is 0.00053 Cd / m ² . Although the work function of L (lithium) itself is low, the work function when LiF is as large as 5.0 eV is considered to be such a low luminance. Even when other materials such as Au (work function is 4.8 eV) or SiO ₂ (work function is 5.0 eV) are used, it is considered that good results can be obtained. On the other hand, it can be seen that the use of simple Mg has a higher luminance than the case of using Al and is not preferable as a material for forming the stress relaxation layer 22. However, this is not the case when used as a compound with another material such as MgO or MgF ₂ instead of Mg alone.

  As described above, the light emitting device D5 according to the present embodiment is similar to the light emitting device D1 (and D2, D3, D4) according to the first embodiment described above between the second electrode 20 and the passivation layer 24. The second electrode 20 having the improved light extraction efficiency during light emission is obtained. The stress relaxation layer 22 is formed of Zn having a work function of 4.9 eV, thereby reducing light emission during black display and improving contrast. Therefore, the display quality is further improved.

<F: Sixth Embodiment>
FIG. 17 is a sectional view showing a structure of a light emitting device D6 according to the sixth embodiment of the present invention. In the above-described fifth embodiment, the light-emitting functional layer 18 is common to all the light-emitting elements U. However, in the light-emitting device D6 according to this embodiment, similarly to the light-emitting device D2 according to the above-described second embodiment, The light emitting functional layer 18 is formed separately for each light emitting color of the light emitting element U.

  That is, as shown in FIG. 17, each light emitting functional layer 18 (18r, 18g, 18b) includes a positive hole injection layer 41 formed on the first electrode 16 and a positive electrode formed on the positive hole injection layer 41. The hole transport layer 43, the light emitting layer 45 (45r, 45g, 45b) formed on the hole transport layer 43, the electron transport layer 47 formed on the light emitting layer 45, and the electron transport layer 47 are formed. And an electron injection layer 49.

  The light emitting functional layer 18r of the light emitting element Ur includes a light emitting layer 45r formed of an organic EL material that generates light in the R (red) wavelength region, and the light emitting functional layer 18g of the light emitting element Ug is in the G (green) wavelength region. The light emitting functional layer 18b of the light emitting element Ub includes a light emitting layer 45b formed of an organic EL material that generates light in the B (blue) wavelength region. Including.

  Similarly to the light emitting device D2, in the light emitting device D6 according to this embodiment, the film thickness of the hole transport layer 43 is the color of light emitted from each light emitting element U (Ur, Ug, Ub). It has been adjusted for emphasis. The aspect of each other component is the same as each component in light-emitting device D5 which concerns on the above-mentioned 5th Embodiment. That is, the stress relaxation layer 22 is made of Zn having a layer thickness of 3 nm. Therefore, description of each component is omitted.

  The light emitting device D6 according to the present embodiment includes the stress relaxation layer 22 between the second electrode 20 and the passivation layer 24 in the same manner as the light emitting device D5 according to the fifth embodiment described above. The second electrode 20 with improved extraction efficiency is obtained. The stress relaxation layer 22 is formed of Zn having a work function of 4.9 eV, thereby reducing light emission during black display and improving contrast. Therefore, the display quality is further improved.

<E: Modification>
The present invention is not limited to the above-described embodiments, and for example, the following modifications are possible. Also, two or more of the modifications shown below can be combined.

(1) Modification 1
In each of the above-described embodiments, the organic EL material of the light emitting layer in the light emitting functional layer 18 is a low molecular material, but the light emitting layer may be formed of an organic EL material of a high molecular material. In this case, the light emitting layer is disposed in a space defined by the partition walls 12 by ink jetting or spin coating.

(2) Modification 2
In each of the embodiments described above, the color filter 32 is provided on the side from which light is emitted in order to increase the purity of the emitted light. However, for example, the color filter 32 may be omitted.

<F: Application example>
Next, an electronic apparatus using the light emitting device according to the present invention will be described. FIG. 13 is a perspective view showing a configuration of a mobile personal computer that employs the light emitting device D1 according to the first embodiment as a display device. The personal computer 2000 includes a light emitting device D1 as a display device and a main body 2010. The main body 2010 is provided with a power switch 2001 and a keyboard 2002. Since this light emitting device D1 uses an OLED element, it is possible to display an easy-to-see screen with a wide viewing angle. 13, the light-emitting device D2 according to the second embodiment, the light-emitting device D3 according to the third embodiment, the light-emitting device D4 according to the fourth embodiment, and the light-emitting device D5 according to the fifth embodiment. The light emitting device D6 according to the sixth embodiment can also be employed.

  FIG. 14 shows a configuration of a mobile phone to which the light emitting device D1 according to the first embodiment is applied. The cellular phone 3000 includes a plurality of operation buttons 3001, scroll buttons 3002, and a light emitting device D1 as a display device. By operating the scroll button 3002, the screen displayed on the light emitting device D1 is scrolled. As the display device in the configuration of FIG. 14, the light emitting device D2 according to the second embodiment, the light emitting device D3 according to the third embodiment, the light emitting device D4 according to the fourth embodiment, and the light emitting device D5 according to the fifth embodiment. The light emitting device D6 according to the sixth embodiment can also be employed.

  FIG. 15 shows a configuration of a portable information terminal (PDA: Personal Digital Assistant) to which the light emitting device D1 according to the first embodiment is applied. The information portable terminal 4000 includes a plurality of operation buttons 4001, a power switch 4002, and a light emitting device D1 as a display device. When the power switch 4002 is operated, various types of information such as an address book and a schedule book are displayed on the light emitting device D1. 15, the light emitting device D2 according to the second embodiment, the light emitting device D3 according to the third embodiment, the light emitting device D4 according to the fourth embodiment, and the light emitting device D5 according to the fifth embodiment. The light emitting device D6 according to the sixth embodiment can also be employed.

  Electronic devices to which the light emitting device according to the present invention is applied include those shown in FIGS. 13 to 15, digital still cameras, televisions, video cameras, car navigation devices, pagers, electronic notebooks, electronic papers, calculators. , Word processors, workstations, videophones, POS terminals, printers, scanners, copiers, video players, devices equipped with touch panels, and the like.

DESCRIPTION OF SYMBOLS 10 ... 1st board | substrate, 12 ... Partition, 14 ... Light reflection layer, 16 ... 1st electrode, 18 ... Light emission functional layer, 20 ... 2nd electrode, 22 ... Stress relaxation layer, 24 ... Passivation layer, 26 ... Sealing layer 30 ... second substrate, 32 ... color filter, 34 ... light shielding film, 35 ... overcoat layer, 64 ... organic buffer layer, 66 ... gas barrier layer, 68 ... transparent adhesive layer, 70 ... circularly polarizing plate, 2000 ... personal computer , 2001 ... power switch, 2002 ... keyboard, 2010 ... main body, 3000 ... mobile phone, 3001 ... operation button, 3002 ... scroll button, 4000 ... information portable terminal, 4001 ... operation button, 4002 ... power switch, D1, D2, D3, D4, D5, D6 ... light emitting device, U ... light emitting element.

Claims (7)

A substrate,
A light reflecting layer formed on the substrate;
A first electrode having transparency formed on the light reflection layer;
A light emitting functional layer formed on the first electrode;
An electron injection layer formed on the light emitting functional layer;
A reducing layer made of a reducible metal material for reducing the electron injecting material forming the electron injecting layer formed on the electron injecting layer;
A second electrode having transflective properties formed on the reducing layer;
A stress relaxation layer for relaxing stress on the second electrode formed on the second electrode;
A passivation layer made of an inorganic material formed on the stress relaxation layer,
The stress relaxation layer formed of the electron injection material is formed of any material of Zn, Al, Au, SnO ₂ , ZnO ₂ , SiO ₂ ,
The second electrode is made of only Ag.
Light emitting device. A substrate,
A light reflecting layer formed on the substrate;
A first electrode having transparency formed on the light reflection layer;
A light emitting functional layer formed on the first electrode;
A mixed layer formed on the light emitting functional layer and mixed with an electron injection material and a reducing metal material for reducing the electron injection material;
A second electrode having transflective properties formed on the mixed layer;
A stress relaxation layer for relaxing stress on the second electrode formed on the second electrode;
A passivation layer made of an inorganic material formed on the stress relaxation layer,
The stress relaxation layer formed of the electron injection material is formed of any material of Zn, Al, Au, SnO ₂ , ZnO ₂ , SiO ₂ ,
The second electrode is made of only Ag.
Light emitting device. The film thickness of the second electrode is in the range of 10 nm to 20 nm.
The light emitting device according to claim 1 . A substrate,
A light reflecting layer formed on the substrate;
A first electrode having transparency formed on the light reflection layer;
A light emitting functional layer formed on the first electrode;
A second electrode having transflective properties formed on the light emitting functional layer;
A stress relaxation layer for relaxing stress on the second electrode formed on the second electrode;
A passivation layer made of an inorganic material formed on the stress relaxation layer,
The light emitting functional layer includes an electron injection layer,
The stress relaxation layer is formed of the same material as the electron injection layer,
The second electrode is made of an alloy containing 75% or more of Ag in atomic ratio,
The light-emitting device in which the stress relaxation layer is formed of any material selected from Zn, Al, Au, SnO ₂ , ZnO ₂ , and SiO ₂ . The light emitting device according to claim 4 , wherein the second electrode is made of an alloy of Mg, Cu, Zn, Pd, Nd, or Al and Ag. The film thickness of the second electrode is in the range of 10 nm to 30 nm.
The light emitting device according to claim 4 or 5 . A method for manufacturing the light emitting device according to any one of claims 4 to 6 ,
Forming a light reflecting layer on the substrate;
Forming a transparent first electrode on the light reflecting layer;
Forming a light emitting functional layer on the first electrode;
Forming a second electrode having transflective properties on the light emitting functional layer;
Forming a stress relaxation layer for relaxing stress on the second electrode on the second electrode;
Forming a passivation layer made of an inorganic material on the stress relaxation layer, and a method of manufacturing a light emitting device,
The step of forming the stress relaxation layer is a step of forming the stress relaxation layer by vapor deposition,
The step of forming the passivation layer includes forming the passivation layer with a plasma generator .
Manufacturing method of light-emitting device.

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