JP5143064B2 - Method for manufacturing light emitting device - Google Patents

Description

  The invention disclosed in this specification relates to a deposition substrate, a deposition method, and a method for manufacturing a light-emitting device.

  Light-emitting elements using organic compounds having characteristics such as thin and light weight, high-speed response, and direct current low-voltage driving as light emitters are applied to next-generation flat panel displays. In particular, a display device in which light emitting elements are arranged in a matrix is considered to be superior to a conventional liquid crystal display device in that it has a wide viewing angle and excellent visibility.

  The light emitting mechanism of the light emitting element is such that when a voltage is applied with an EL layer sandwiched between a pair of electrodes, electrons injected from the cathode and holes injected from the anode are recombined at the emission center of the EL layer. It is said that when excitons are formed and the molecular excitons relax to the ground state, they emit energy and emit light. Singlet excitation and triplet excitation are known as excited states, and light emission is considered to be possible through either excited state.

  The EL layer included in the light-emitting element has at least a light-emitting layer. In addition, the EL layer can have a stacked structure including a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, and the like in addition to the light-emitting layer.

  Further, EL materials for forming the EL layer are roughly classified into low molecular (monomer) materials and high molecular (polymer) materials. In general, a low molecular material is often formed using a vapor deposition method, and a high molecular material is often formed using an inkjet method or the like.

  A vapor deposition apparatus used in the case of the vapor deposition method includes a substrate holder on which a substrate is installed, an EL material, that is, a crucible (or vapor deposition boat) enclosing the vapor deposition material, a heater for heating the EL material in the crucible, and an EL that sublimates. A shutter for preventing diffusion of the material, and the EL material heated by the heater is sublimated to form a film on the substrate.

  However, in practice, in order to uniformly form a film, it is necessary to rotate the deposition target substrate and to keep the distance between the substrate and the crucible more than a certain value. In addition, when performing painting through a mask such as a metal mask using a plurality of EL materials, design a wide interval between different pixels and widen a partition made of an insulating material provided between the pixels. This is a major issue in increasing the fineness (increasing the number of pixels) of a light emitting device including a light emitting element and miniaturizing each display pixel pitch accompanying downsizing.

  Therefore, in order to achieve higher definition as a flat panel display, it is required to solve these problems and improve productivity and cost reduction.

  On the other hand, a method of forming an EL layer of a light emitting element by laser thermal transfer has been proposed (see Patent Document 1).

  Patent Document 1 describes a transfer substrate having a photothermal conversion layer composed of a low reflection layer and a high reflection layer and a transfer layer on a support substrate. By irradiating such a transfer substrate with laser light, the laser light is reflected by the high reflection layer, absorbed by the low reflection layer, and converted into heat, so that the EL layer on the low reflection layer is sublimated and transferred. Is done.

JP 2006-309995 A

  When a light source such as a halogen lamp or a flash lamp is used to form a material layer in which two or more types of materials having different sublimation temperatures are mixed, the irradiation time of the light source is long, so that the material with the lower sublimation temperature is applied first. After that, a material having a high sublimation temperature is sublimated later and formed on the deposition substrate.

  If a mixed layer with a non-uniform concentration gradient is formed on the deposition substrate due to a difference in sublimation temperature, there is a possibility that a problem of adversely affecting characteristics such as emission color may occur.

  Therefore, in the invention described in this specification, in a method for forming a material layer including materials having different sublimation temperatures formed on a transfer substrate on a deposition substrate by light irradiation, the material layer is formed on the deposition substrate. One of the problems is to form a film with a uniform concentration on the top.

  A cap layer is formed on a material layer formed by mixing two or more materials having different sublimation temperatures formed on the transfer substrate. As a material constituting the cap layer, a material having a higher sublimation temperature than the material used for the material layer is desirable.

  By forming the cap layer, even if a material obtained by mixing two or more materials having different sublimation temperatures is sublimated, a mixed film that is almost uniformly mixed can be formed on the deposition target substrate.

  One embodiment of the present invention includes a light absorption layer formed over a substrate, a material layer formed over the light absorption layer, and a cap layer formed over the material layer. It is related with a substrate.

  In one embodiment of the present invention, a reflective layer formed over a substrate and having an opening, a light absorption layer formed over the substrate and the reflective layer, a material layer formed over the light absorption layer, The present invention relates to a film formation substrate having a cap layer formed on the material layer.

  According to one aspect of the present invention, a reflective layer formed on a substrate and having an opening, a heat insulating layer formed on the substrate and the reflective layer, a light absorption layer formed on the heat insulating layer, The present invention relates to a film formation substrate comprising a material layer formed on a light absorption layer and a cap layer formed on the material layer.

  The cap layer is formed using a metal having a higher sublimation temperature than the material layer.

  The material of the cap layer is formed using an inorganic compound having a higher sublimation temperature than the material layer.

  The material of the cap layer is formed using an organic compound having a higher sublimation temperature than the material layer.

  The cap layer includes one or more of aluminum, calcium fluoride, and lithium fluoride (LiF).

  The light absorption layer includes any one or more of titanium nitride, tantalum nitride, molybdenum nitride, tungsten nitride, chromium nitride, manganese nitride, molybdenum, titanium, tungsten, and carbon.

  The reflective layer is any one of aluminum, silver, gold, platinum, copper, an aluminum-titanium alloy, an aluminum-neodymium alloy, an alloy containing aluminum such as an aluminum-titanium alloy, and an alloy containing silver such as a silver-neodymium alloy, Or two or more are included.

  The thermal conductivity of the material used for the heat insulation layer is smaller than the thermal conductivity of the material used for the reflective layer and the light absorption layer.

  The heat insulating layer includes one or more of titanium oxide, silicon oxide, silicon nitride oxide, zirconium oxide, and silicon carbide.

  According to one embodiment of the present invention, a light absorption layer, a material layer including two or more kinds of host and guest materials having different sublimation temperatures, and a sublimation temperature higher than that of the material layer are provided on the first surface of the first substrate. Forming a cap layer of material, with a first surface of the second substrate facing the first surface of the first substrate and being a surface opposite to the first surface of the first substrate; By irradiating light from the second surface and sublimating the material layer, a mixed layer in which the two or more types of host and guest materials are mixed is formed on the first surface of the second substrate. The present invention relates to a film forming method.

  According to one embodiment of the present invention, a reflective layer is formed in a first region on a first surface of a first substrate, and the reflective layer is formed on the reflective layer and on the first substrate. A light absorption layer is formed on the second region that is not, a material layer containing two or more kinds of host and guest materials having different sublimation temperatures on the light absorption layer, and a material having a higher sublimation temperature than the material layer A second layer which is a surface opposite to the first surface of the first substrate, with the first surface of the second substrate facing the first surface of the first substrate. By irradiating light from the surface of the second substrate and sublimating the material layer on the light absorption layer on the second region, the two or more types of hosts and the first surface of the second substrate are formed. The present invention relates to a film forming method characterized by forming a mixed layer in which a guest material is mixed.

  According to one embodiment of the present invention, a reflective layer is formed in a first region on a first surface of a first substrate, and the reflective layer is formed on the reflective layer and on the first substrate. A light absorption layer is formed on the second region that is not, a material layer containing two or more kinds of host and guest materials having different sublimation temperatures on the light absorption layer, and a material having a higher sublimation temperature than the material layer Forming a cap layer, forming a first electrode which is one of an anode and a cathode on the first surface of the second substrate, and forming a partition wall which overlaps with an end of the first electrode; The first surface of the second substrate is opposed to the first surface of the first substrate, and light is irradiated from a second surface that is the surface opposite to the first surface of the first substrate. By sublimating the material layer on the light absorption layer on the second region, the two or more types of hosts and gates are formed on the first electrode. Forming a preparative material mixture layer is mixed, on the mixed layer, a process for fabricating a light-emitting device and forming a second electrode which is the other of the anode or cathode.

  The cap layer includes one or more of aluminum, silver, calcium fluoride, and lithium fluoride (LiF).

  The light absorption layer includes any one or more of titanium nitride, tantalum nitride, molybdenum nitride, tungsten nitride, chromium nitride, manganese nitride, molybdenum, titanium, tungsten, and carbon.

  The reflective layer is any one of aluminum, silver, gold, platinum, copper, an aluminum-titanium alloy, an aluminum-neodymium alloy, an alloy containing aluminum such as an aluminum-titanium alloy, and an alloy containing silver such as a silver-neodymium alloy, Or two or more are included.

  Of the material layers containing the two or more types of host and guest materials, the host material is 9- [4- (10-phenyl-9-anthryl) phenyl] -9H-carbazole (abbreviation: CzPA), and the two types Of the above-described material layers containing the host and guest materials, the guest material is N- (9,10-diphenyl-2-anthryl) -N, 9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCAPA). .

  Even when a material layer containing materials having different sublimation temperatures is sublimated on the transfer substrate to form a mixed layer on the film formation substrate, the materials having different sublimation temperatures are formed almost uniformly without separation.

  In addition, as described above, a highly reliable light-emitting device with stable characteristics such as emission color can be manufactured.

Sectional drawing which shows the film-forming board | substrate and the film-forming method. Sectional drawing which shows the film-forming board | substrate and the film-forming method. The figure which shows a photoluminescence spectrum. The figure which shows a photoluminescence spectrum. The figure which shows a photoluminescence spectrum. The figure which shows a photoluminescence spectrum. FIG. 14 illustrates an example of an electronic device. FIG. 14 illustrates an example of an electronic device. The figure which shows the result of ToF-SIMS. The figure which shows the result of ToF-SIMS. The figure which shows the result of ToF-SIMS. The figure which shows the cutting method of a sample in the measurement of ToF-SIMS. 9 is a cross-sectional view illustrating a method for manufacturing a light-emitting device. 9 is a cross-sectional view illustrating a method for manufacturing a light-emitting device. 9 is a cross-sectional view illustrating a method for manufacturing a light-emitting device. The top view which shows arrangement | positioning of a light emitting layer. 9 is a cross-sectional view illustrating a method for manufacturing a light-emitting device. Sectional drawing which shows the film-forming board | substrate and the film-forming method.

  Hereinafter, embodiments of the invention disclosed in this specification will be described with reference to the drawings. However, the invention disclosed in this specification can be implemented in many different modes, and various changes can be made in form and details without departing from the spirit and scope of the invention disclosed in this specification. It will be readily understood by those skilled in the art. Therefore, the present invention is not construed as being limited to the description of this embodiment mode. Note that in the drawings described below, the same portions or portions having similar functions are denoted by the same reference numerals, and repetitive description thereof is omitted.

  Note that in the invention disclosed in this specification, a semiconductor device refers to all elements and devices that function by using a semiconductor, and includes an electric device including an electronic circuit, a display device, a light-emitting device, and the like, and the electric device. The category is the electronic equipment.

[Embodiment 1]
This embodiment is described with reference to FIGS. 1A to 1D, 2A to 2D, FIGS. 3, 4, 5, 6, 9, 10, and 11. This will be described with reference to FIGS. 12 (A) to 12 (C).

  In FIG. 1A, a light absorption layer 103 is formed over a first substrate 101 which is a supporting substrate.

  Note that as the first substrate 101, a glass substrate, a quartz substrate, a plastic substrate containing an inorganic material, or the like, or a substrate made of molybdenum or tungsten can be used.

  The light absorption layer 103 is a layer that absorbs light irradiated during vapor deposition. Therefore, the light absorption layer 103 is preferably formed of a material having a low reflectance with respect to the irradiation light and a high absorption rate. Specifically, the light absorption layer 103 preferably exhibits a reflectance of 70% or less with respect to the irradiated light.

  Examples of a material that can be used for the light absorption layer 103 include metal nitrides such as titanium nitride, tantalum nitride, molybdenum nitride, tungsten nitride, chromium nitride, and manganese nitride, molybdenum, titanium, tungsten, and carbon. It is preferable to use it. Note that the light absorption layer 103 is not limited to a single layer, and may include a plurality of layers.

  Thus, since the kind of material suitable for the light absorption layer 103 varies depending on the wavelength of light to be irradiated, it is necessary to select a material as appropriate.

  The light absorption layer 103 can be formed using various methods. For example, it can be formed by sputtering, electron beam vapor deposition, vacuum vapor deposition, or the like.

  The thickness of the light absorption layer 103 varies depending on the material, but it is preferable that the thickness of the light absorption layer 103 be such that irradiated light is not transmitted (preferably 100 nm to 2 μm). In particular, by setting the thickness of the light absorption layer 103 to 100 nm or more and 600 nm or less, it is possible to efficiently absorb irradiated light and generate heat. In addition, when the thickness of the light absorption layer 103 is greater than or equal to 100 nm and less than or equal to 600 nm, deposition onto the deposition target substrate can be performed with high accuracy.

  Note that as long as the light absorption layer 103 can be heated to the sublimation temperature of the evaporation material included in the material layer 104, part of the light to be irradiated may pass therethrough. However, in the case where part of the light is transmitted, it is necessary to use a material that is not decomposed by light as an evaporation material included in the material layer 104.

  Next, the material layer 104 is formed over the light absorption layer 103, and the cap layer 105 is further formed over the material layer 104 (see FIG. 1B). Thereby, a film formation substrate is obtained.

  In this embodiment, the material layer 104 has a structure in which a guest material is dispersed in a host material that is a substance in which a light-emitting material is dispersed, using a dopant material that is a highly light-emitting material as a guest material. That is, a layer in which the host material and the guest material are mixed is formed as the material layer 104. Alternatively, a structure in which a host material and a guest material are stacked may be used.

  Note that as the material layer 104, two or more kinds of host materials and guest materials may be used, or a structure in which two or more kinds of host materials and guest materials are stacked may be used.

  Examples of the host material and guest material are given below. For example, blue to blue-green light emission is dispersed in a suitable host material using perylene, 2,5,8,11-tetra-t-butylperylene (abbreviation: TBP), 9,10-diphenylanthracene, etc. as a guest material. To obtain. In addition, styrylarylene derivatives such as 4,4′-bis (2,2-diphenylvinyl) biphenyl (abbreviation: DPVBi), 9,10-di-2-naphthylanthracene (abbreviation: DNA), 9,10-bis It can be obtained from an anthracene derivative such as (2-naphthyl) -2-t-butylanthracene (abbreviation: t-BuDNA).

  In addition, as the blue light emitting guest material, a styrylamine derivative is preferable, and N, N′-bis [4- (9H-carbazol-9-yl) phenyl] -N, N′-diphenylstilbene-4,4′- Examples include diamine (abbreviation: YGA2S) and N, N′-diphenyl-N, N′-bis (9-phenyl-9H-carbazol-3-yl) stilbene-4,4′-diamine (abbreviation: PCA2S). It is done. In particular, YGA2S is preferable because it has a peak in the vicinity of 450 nm. As the host material, an anthracene derivative is preferable, and 9,10-bis (2-naphthyl) -2-t-butylanthracene (abbreviation: t-BuDNA) or 9- [4- (10-phenyl-9-) is preferable. Anthryl) phenyl] -9H-carbazole (abbreviation: CzPA) is preferred. In particular, CzPA is preferable because it is electrochemically stable.

  For example, blue-green to green light is emitted from coumarin dyes such as coumarin 30 and coumarin 6, bis [2- (2,4-difluorophenyl) pyridinato] picolinatoiridium (abbreviation: FIrpic), bis (2-phenylpyri). Dinat) acetylacetonatoiridium (Ir (ppy) 2 (acac)) or the like is used as a guest material and dispersed in a suitable host material. It can also be obtained by dispersing the above-described perylene or TBP in a suitable host material at a high concentration of 5 wt% or more. It can also be obtained from metal complexes such as BAlq, Zn (BTZ) 2, bis (2-methyl-8-quinolinolato) chlorogallium (Ga (mq) 2Cl).

  As a guest material for the blue-green to green light-emitting layer, an anthracene derivative is preferable because highly efficient light emission can be obtained. For example, by using 9,10-bis {4- [N- (4-diphenylamino) phenyl-N-phenyl] aminophenyl} -2-tert-butylanthracene (abbreviation: DPABPA), highly efficient blue-green Luminescence is obtained. An anthracene derivative in which an amino group is substituted at the 2-position is preferable because highly efficient green light emission can be obtained, and N- (9,10-diphenyl-2-anthryl) -N, 9-diphenyl-9H-carbazole-3 is preferable. An amine (abbreviation: 2PCAPA) is particularly preferable because of its long life.

  As these host materials, anthracene derivatives are preferable, and CzPA described above is preferable because it is electrochemically stable. Further, when green light emission and blue light emission are combined to produce a light-emitting element having two peaks in the blue to green wavelength region (for example, when the second light-emitting element shown in the first embodiment described above is produced), When an electron transporting anthracene derivative such as CzPA is used for the host of the blue light emitting layer and a hole transporting aromatic amine compound such as NPB is used for the host of the green light emitting layer, the blue light emitting layer and the green light emitting layer It is preferable because light emission can be obtained at the interface. That is, in this case, an aromatic amine compound such as NPB is preferable as the host of the green light emitting material such as 2PCAPA.

  For example, yellow to orange light emission is obtained from rubrene, 4- (dicyanomethylene) -2- [p- (dimethylamino) styryl] -6-methyl-4H-pyran (abbreviation: DCM1), 4- (dicyanomethylene) -2. -Methyl-6- (9-julolidyl) ethynyl-4H-pyran (abbreviation: DCM2), bis [2- (2-thienyl) pyridinato] acetylacetonatoiridium (Ir (thp) 2 (acac)), bis (2 -Phenylquinolinato) acetylacetonatoiridium (Ir (pq) 2 (acac)) or the like is used as a guest material and dispersed in a suitable host material. In particular, a tetracene derivative such as rubrene is preferable as a guest material because it is highly efficient and chemically stable.

  In this case, the host material is preferably an aromatic amine compound such as NPB. As another host material, a metal complex such as bis (8-quinolinolato) zinc (abbreviation: Znq2) or bis [2-cinnamoyl-8-quinolinolato] zinc (abbreviation: Znsq2) can be used.

  For example, light emission of orange to red is caused by 4- (dicyanomethylene) -2,6-bis [p- (dimethylamino) styryl] -4H-pyran (abbreviation: BisDCM), 4- (dicyanomethylene) -2,6- Bis [2- (julolidin-9-yl) ethynyl] -4H-pyran DCM1), 4- (dicyanomethylene) -2-methyl-6- (9-julolidyl) ethynyl-4H-pyran (abbreviation: DCM2), bis [2- (2-Thienyl) pyridinato] acetylacetonatoiridium (Ir (thp) 2 (acac)), etc. is used as a guest material and dispersed in a suitable host material. It can also be obtained from a metal complex such as bis (8-quinolinolato) zinc (abbreviation: Znq2) or bis [2-cinnamoyl-8-quinolinolato] zinc (abbreviation: Znsq2). As guest materials that exhibit red light emission, 4- (dicyanomethylene) -2,6-bis [p- (dimethylamino) styryl] -4H-pyran (abbreviation: BisDCM), 4- (dicyanomethylene) -2,6 -Bis [2- (julolidin-9-yl) ethynyl] -4H-pyran DCM1), 4- (dicyanomethylene) -2-methyl-6- (9-julolidyl) ethynyl-4H-pyran (abbreviation: DCM2), {2-Isopropyl-6- [2- (2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H, 5H-benzo [ij] quinolizin-9-yl) ethenyl] -4H -Pyran-4-ylidene} propanedinitrile (abbreviation: DCJTI), {2,6-bis [2- (2,3,6,7-tetrahydro-8-methoxy-1,1,7,7-tetramethyl) 1H, 5H-benzo [ij] quinolizin-9-yl) ethenyl] -4H-pyran-4-ylidene} propanedinitrile (abbreviation: BisDCJTM) is highly efficient and is particularly preferable. DCJTI and BisDCJTM are preferable because they have an emission peak near 620 nm.

  Note that in the above structure, a suitable host material may be any material that emits light with a shorter wavelength or has a larger energy gap than the light-emitting organic compound. Specifically, it can be appropriately selected from hole transport materials and electron transport materials represented by the examples described above. In addition, 4,4′-bis (N-carbazolyl) biphenyl (abbreviation: CBP), 4,4 ′, 4 ″ -tris (N-carbazolyl) triphenylamine (abbreviation: TCTA), 1,3,5- Tris [4- (N-carbazolyl) phenyl] benzene (abbreviation: TCPB) or the like may be used.

  As a material constituting the cap layer 105, a material having a higher sublimation temperature than the material used for the material layer 104 is desirable. As a material constituting the cap layer 105, a metal, an inorganic compound, or an organic compound can be used. The cap layer 105 may be a laminate of two or more materials or a mixture of two or more materials.

  When a metal is used as the material constituting the cap layer 105, for example, aluminum (Al), silver (Ag), or the like can be used. When an inorganic compound is used as the material constituting the cap layer 105, for example, calcium fluoride (CaF2), lithium fluoride (LiF), or the like can be used. Alternatively, a combination of these materials may be used.

  Examples of a method for forming the cap layer 105 include a wet method, a vacuum deposition method, a sputtering method, a CVD method, and the like. A vacuum deposition method that does not damage the material layer 104 is more preferable.

  The film thickness of the cap layer 105 varies depending on the material of the cap layer 105 and the material layer 104, but when aluminum (Al) is used for the cap layer 105, 5 nm to 20 nm is preferable.

  Next, one surface of the second substrate 111 which is a deposition substrate is opposed to the surface of the first substrate 101 on which the material layer 104 and the cap layer 105 are formed. Then, light 107 is irradiated from the other surface of the second substrate 111 (see FIG. 1C). The light 107 is absorbed by the light absorption layer 103. Heat is generated from the light absorbed by the light absorption layer 103, and the vapor deposition material of the material layer 104 is sublimated by this heat.

  In this embodiment mode, laser light is used as an example of the light 107. Laser light includes Ar laser, Kr laser, excimer laser and other gas lasers, single crystal YAG, YVO4, forsterite (Mg2SiO4), YAlO3, GdVO4, or polycrystalline (ceramic) YAG, Y2O3, YVO4, YAlO3, Laser, glass laser, ruby laser, alexandrite laser, Ti: sapphire using GdVO4 as a medium with one or more of Nd, Yb, Cr, Ti, Ho, Er, Tm, Ta added as a dopant A laser oscillated from one or a plurality of solid lasers such as a laser and a fiber laser can be used. Moreover, the second harmonic or the third harmonic oscillated from the solid-state laser can also be used. Note that the use of a solid-state laser whose laser medium is solid has the advantage that a maintenance-free state can be maintained for a long time and the output is relatively stable.

  As the above-described laser, a pulse laser, a continuous wave (CW: continuous-wave) laser, or the like can be used. In the case of a pulse laser, for example, a laser beam having a frequency of 1 MHz or more can be used as well as a frequency of several Hz to several hundred kHz. The shape of the laser spot is preferably linear or rectangular.

  As the light 107, lamp light can be used as light other than laser light. When lamp light is used, a flash lamp (such as a xenon flash lamp or a krypton flash lamp), a discharge lamp such as a xenon lamp or a metal halide lamp, or a heating lamp such as a halogen lamp or a tungsten lamp can be used. The flash lamp can irradiate a large area in a short time (0.1 to 10 milliseconds). In addition, the amount of light irradiation can be controlled by changing the time interval of light emission. Moreover, since the flash lamp has a long life and low power consumption during light emission standby, the running cost can be kept low.

  The irradiation with the light 107 is preferably performed in a reduced-pressure atmosphere. Therefore, it is preferable to set the atmosphere in the processing chamber to 5 × 10 −3 Pa or less, preferably 10 −6 Pa to 10 −4 Pa.

  The vapor deposition material of the material layer 104 is sublimated by heat obtained from the light absorbed by the light absorption layer 103, and the host material and the surface of the second substrate 111, that is, the surface facing the first substrate 101 are A mixed layer 108 in which the guest material is mixed is formed. Note that the cap layer 105 remains on the light absorption layer 103 (see FIG. 1D).

  1A to 1D show the film formation substrate and the film formation method when only the light absorption layer 103 is formed, but the film formation substrate and the film formation method when the reflective layer 102 is formed. The method will be described with reference to FIGS. 2 (A) to 2 (D).

  The reflective layer 102 and the light absorption layer 103 are formed over the first substrate 101 (see FIG. 2A).

  The reflective layer 102 is a layer that selectively irradiates the light absorbing layer 103 with the light 107 and reflects the light irradiated to other portions when the light 107 is irradiated. Therefore, the reflective layer 102 is preferably formed of a material having a high reflectance with respect to the light 107. Specifically, the reflective layer 102 preferably has a reflectance of 85% or more, more preferably 90% or more, with respect to the irradiated light.

  Examples of a material that can be used for the reflective layer 102 include aluminum, silver, gold, platinum, copper, an alloy containing aluminum (eg, an aluminum-titanium alloy, an aluminum-neodymium alloy, and an aluminum-titanium alloy), or An alloy containing silver (silver-neodymium alloy) or the like can be used.

  Note that the reflective layer 102 can be formed by various methods. For example, it can be formed by sputtering, electron beam vapor deposition, vacuum vapor deposition, or the like. Moreover, although the film thickness of the reflective layer 102 changes with materials, it is preferable to set it as 100 nm or more. By setting the film thickness to 100 nm or more, the irradiated light 107 can be prevented from passing through the reflective layer 102.

  Next, similarly to the process illustrated in FIG. 1B, the material layer 104 and the cap layer 105 are formed over the light absorption layer 103 (see FIG. 2B). Thereby, a film formation substrate is obtained.

  Next, similarly to the process illustrated in FIG. 1C, one surface of the second substrate 111 is opposed to the surface of the first substrate 101 on which the material layer 104 and the cap layer 105 are formed. Then, light 107 is irradiated from the other surface of the second substrate 111 (see FIG. 2C). The light 107 is absorbed by the light absorption layer 103 and reflected by the reflection layer 102. Heat is generated from the light absorbed in the light absorption layer 103, and the material of the material layer 104 on the light absorption layer 103 is sublimated by this heat.

  With the heat obtained from the light absorbed by the light absorption layer 103, the material of the material layer 104 is sublimated, and the mixed layer 108 is formed on the surface of the second substrate 111. On the other hand, the material layer 104 on the reflective layer 102 remains without being sublimated. The cap layer 105 remains on the light absorption layer 103 and the reflective layer 102 (see FIG. 1D).

  Here, the effects of the presence or absence of the cap layer 105, the difference in the material of the cap layer 105, and the thickness of the cap layer 105 are shown in FIGS. 3, 4, 5, 6, 9, 10, and 11. Will be described.

  3, FIG. 4, FIG. 5 and FIG. 6 show photoluminescence (PL) spectra. The PL spectrum is a spectrum that represents the wavelength and intensity of light emitted from the mixed layer 108 by irradiating light having an excitation wavelength.

  In this embodiment, 2PCAPA is used as the guest material and CzPA is used as the host material for the material layer 104. The sublimation temperature of 2PCAPA is 260 ° C. and the sublimation temperature of CzPA is 210 ° C. in a vacuum (degree of vacuum: 10 −3 Pa). For this reason, if a time difference arises in raising the temperature from 210 ° C. to 260 ° C., CzPA sublimates first, and 2PCAPA sublimates later.

  FIG. 3 shows the PL spectrum (thin solid line) of the mixed layer 108 that has been sublimated by light irradiation without using the cap layer 105 and the PL spectrum (thick solid line) of the material layer 104 before light irradiation. .

  Although the PL spectrum (thick solid line) of the material layer 104 has only a peak B near 520 nm, when the material layer 104 is sublimated by being irradiated with the light 107 and deposited on the substrate 111, a peak A near 450 nm and Two peaks called peak B near 520 nm are generated. This is because when the guest material and the host material are irradiated with the light 107, the light absorption layer 103 absorbs the light 107 and changes to heat, and CzPA having a low sublimation temperature is first sublimated in the process of raising the temperature. This occurs because 2PCAPA having a high temperature is sublimated later, thereby creating a concentration gradient in the mixed layer 108.

  FIG. 4 shows a PL spectrum without the cap layer 105 (thin solid line), and a PL spectrum (thin broken line) of the mixed layer 108 after irradiation with an aluminum (Al) film having a film thickness of 5 nm as the cap layer 105. The PL spectrum (thin dotted line) of the mixed layer 108 after light irradiation is formed by forming an aluminum (Al) film with a film thickness of 10 nm as the cap layer 105.

  In FIG. 4, when an aluminum film is formed as the cap layer 105, the PL spectrum of the mixed layer 108 after light irradiation is not split into two peaks, peak A and peak B, and only one peak exists. . This means that 2PCAPA as the guest material and CzPA as the host material are not separated and are almost uniformly mixed.

  Moreover, the shape of the PL spectrum does not change even if the film thickness of the aluminum film is 5 nm or 10 nm.

  FIG. 5 shows a PL spectrum (thin solid line) of the mixed layer 108 after light irradiation in the absence of the cap layer 105, and a calcium fluoride (CaF2) film having a film thickness of 5 nm as the cap layer 105, which was irradiated with light. PL spectrum of thin mixed layer 108 (thin one-dot broken line), a calcium fluoride (CaF2) film having a film thickness of 10 nm as cap layer 105, and PL spectrum of thin mixed layer 108 after light irradiation (thin two-dot dotted line) Is shown.

  In FIG. 5, the emission of the host material (peak A) is suppressed as compared with the PL spectrum without the cap layer 105. This indicates that the guest material is mixed as compared with the case where the host material does not have the cap layer 105.

  Further, the shape of the PL spectrum does not change even if the thickness of the calcium fluoride film is 5 nm or 10 nm.

  In FIG. 6, the PL spectrum (thin solid line) of the mixed layer 108 after light irradiation without the cap layer 105 and an aluminum (Al) film having a film thickness of 10 nm as the cap layer 105 are formed and irradiated with light. The PL spectrum (thin dotted line) of the mixed layer 108 and the PL spectrum (thin two-dotted line) of the mixed layer 108 after light irradiation with a calcium fluoride (CaF2) film formed as a cap layer 105 with a film thickness of 10 nm are shown. .

  As shown in FIG. 6, even with the same film thickness, the aluminum film emits less light (peak A) from the host material than the calcium fluoride film, and the aluminum film functions more as the cap layer 105. I understand that

  Next, FIGS. 9, 10, and 11 are ToF-SIMS data. This ToF-SIMS data is obtained by measuring the concentration distribution in the depth direction in the surface and in the film by cutting the sample obliquely.

  9, 10, and 11, the horizontal axis represents the measurement position, and the vertical axis represents the secondary ion intensity.

  In the measurement of ToF-SIMS, how to cut the sample will be described with reference to FIGS. A stacked structure including the first layer 125, the second layer 124, the third layer 123, the fourth layer 122, and the surface 121 (see FIG. 12A) is cut along a line 127 (see FIG. 12 (B)).

  In the stacked structure cut along the line 127, the surface 121 and the slopes of the first layer 125, the second layer 124, the third layer 123, and the fourth layer 122 are exposed. FIG. 12C is a top view of the surface 121 and the exposed first layer 125, second layer 124, third layer 123, and fourth layer 122 from above. 9 to 11 are ToF-SIMS data in FIG. 12C, respectively. 9 to 11, each region C is a region on the substrate 111 side which is a deposition substrate, region B is a region in the film, and region A is a surface.

  9 shows ToF-SIMS data when the cap layer 105 is provided, and FIG. 10 shows ToF-SIMS data when the cap layer 105 is not provided. The measurement position shown in FIG. 12C is taken as the X axis, and the secondary ion intensity is taken as the Y axis. 9 and 10 show ToF-SIMS data of the mixed layer 108 transferred to the substrate 111.

  In FIG. 9, a peak of CzPA, which is a host material, is observed in region B in the film. However, near the boundary between the region B and the region A (x = 130 μm), the secondary ion intensity decreases and thereafter becomes constant.

  On the other hand, in the case of 2PCAPA, which is a guest material, the secondary ion intensity increases in the region C and the region B, and a constant strength is maintained in the region A.

  That is, in region A, it is shown that CzPA as the host material and 2PCAPA as the guest material are mixed at a constant concentration.

  In FIG. 10, a CzPA peak is observed in the region B. On the other hand, 2PCAPA has a low secondary ion intensity in the region C and the region B, and the secondary ion intensity increases in the vicinity of the distance of 200 μm to 160 μm, which is near the boundary between the region B and the region A. In region A, the secondary ionic strength of 2PCAPA is almost constant.

  From FIG. 10, it can be seen that the peak of CzPA and the peak of 2PCAPA are deviated, and that there is much CzPA in the region C close to the substrate 111 and 2PCAPA in the region A close to the surface. This means that CzPA having a lower sublimation temperature sublimated first, and 2PCAPA having a higher sublimation temperature sublimated later than CzPA. If the guest material and the host material are separated in this way, the EL characteristics such as the emission color are adversely affected.

  For comparison, FIG. 11 shows ToF-SIMS data of the material layer 104 shown in FIG. The material layer 104 is a mixed layer of CzPA and 2PCAPA.

  As shown in FIG. 11, in regions A to C, both CzPA and 2PCAPA maintain substantially the same secondary ion intensity. That is, when the sublimation process is performed in a state where the cap layer 105 does not exist, CzPA as the host material and 2PCAPA as the guest material are separated as shown in FIG. However, when the cap layer 105 is provided, as shown in FIG. 9, the mixed state of CzPA as the host material and 2PCAPA as the guest material can be improved even after the sublimation process. Thereby, EL characteristics can be improved.

  Next, using FIG. 2A to FIG. 2D, not only the light absorption layer 103 but also the reflective layer 102 is formed over the first substrate 101, and the mixed layer 108 is formed over the second substrate 111. A method of selectively forming will be described.

  A reflective layer 102 is selectively formed over the first substrate 101, and a light absorption layer 103 is formed over the reflective layer 102 and a region where the reflective layer 102 of the substrate 101 is not formed (FIG. 2). (See (A)). Note that although the light absorption layer 103 is formed over the reflective layer 102 in FIG. 2A, the light absorption layer 103 is selectively formed, and the light absorption layer 103 of the substrate 101 is formed over the light absorption layer 103. The reflective layer 102 may be formed on a region that has not been formed.

  The reflective layer 102 is a layer that selectively irradiates the light absorption layer 103 with light 107 shown in FIG. 2C and reflects the light irradiated to other portions. Therefore, the reflective layer 102 is preferably formed of a material having a high reflectance with respect to the light 107. Specifically, the reflection layer 102 has a reflectance of 85% or more, more preferably 90% or more, with respect to the irradiated light 107.

  Examples of a material that can be used for the reflective layer 102 include aluminum, silver, gold, platinum, copper, an alloy containing aluminum (eg, an aluminum-titanium alloy, an aluminum-neodymium alloy, and an aluminum-titanium alloy), or An alloy containing silver (silver-neodymium alloy) or the like can be used.

  Note that the reflective layer 102 can be formed by various methods. For example, it can be formed by sputtering, electron beam vapor deposition, vacuum vapor deposition, or the like. Moreover, although the film thickness of the reflective layer 102 changes with materials, it is preferable to set it as 100 nm or more. By setting the film thickness to 100 nm or more, the irradiated light 107 can be prevented from passing through the reflective layer 102.

  Next, the material layer 104 and the cap layer 105 are formed over the light absorption layer 103 (see FIG. 2B). Note that in the case where the reflective layer 102 is formed over the light absorption layer 103, the material layer 104 and the cap layer 105 are formed over the reflective layer 102.

  Next, one surface of the second substrate 111 which is a deposition substrate is opposed to the surface of the first substrate 101 on which the material layer 104 and the cap layer 105 are formed. Then, light 107 is irradiated from the other surface of the second substrate 111 (see FIG. 2C). The light 107 is reflected by the reflection layer 102 and absorbed by the light absorption layer 103. Heat is generated from the light absorbed in the light absorption layer 103, and the material of the material layer 104 on the light absorption layer 103 is sublimated by this heat. The material of the material layer 104 on the reflective layer 102 remains on the reflective layer 102 without being sublimated.

  By irradiation with light 107, the vapor deposition material of the material layer 104 over the light absorption layer 103 is sublimated, so that the mixed layer 108 is formed over the second substrate 111. The material of the material layer 104 over the reflective layer 102 is not sublimated, and the mixed layer 108 is not formed in the region of the second substrate 111 corresponding to the reflective layer 102 (see FIG. 2D).

  18A to 18D, not only the light absorption layer 103 but also the reflective layer 102 and the heat insulating layer 109 are formed over the first substrate 101, and the second substrate 111 is formed over the second substrate 111. A method for selectively forming the mixed layer 108 will be described.

  A reflective layer 102 is selectively formed over the first substrate 101, and a heat insulating layer 109 is formed over the reflective layer 102 (see FIG. 18A).

  The heat insulating layer 109 is a layer for suppressing the material layer 104 formed on the reflective layer 102 from being heated and sublimated. As the heat insulating layer 109, for example, titanium oxide, silicon oxide, silicon oxynitride, zirconium oxide, titanium carbide, or the like can be preferably used. Note that the heat insulating layer 109 is formed using a material having lower thermal conductivity than the material used for the reflective layer 102 and the light absorbing layer 103. Note that in this specification, oxynitride is a substance having a higher oxygen content than nitrogen in its composition.

  The heat insulating layer 109 can be formed using various methods. For example, it can be formed by sputtering, electron beam evaporation, vacuum evaporation, CVD, or the like. The thickness of the heat insulating layer 109 varies depending on the material, and can be 10 nm to 2 μm, preferably 100 nm to 600 nm. By setting the heat insulating layer 109 to a thickness of 10 nm to 2 μm, even when the reflective layer 102 is heated, there is an effect of blocking heat conduction to the material layer 104 positioned on the reflective layer 102.

  Further, the heat insulating layer 109 is not formed in a region where the reflective layer 102 is not formed. When forming the heat insulating layer 109, a material film to be the heat insulating layer 109 is formed over the substrate 101 and the reflective layer 102, and the material film in a region other than the reflective layer 102 may be removed. Various methods can be used to form the heat insulating layer 109 in this manner, but dry etching is preferably used. By using dry etching, the side wall of the heat insulating layer 109 becomes sharp and a fine pattern can be formed.

  Next, the light absorption layer 103 is formed over the substrate 101 and the heat insulating layer 109. Next, the material layer 104 is formed over the light absorption layer 103, and the cap layer 105 is formed over the material layer 104. As described above, a deposition substrate is manufactured (see FIG. 18B).

  Next, one surface of the second substrate 111 which is a deposition substrate is opposed to the surface of the first substrate 101 on which the material layer 104 and the cap layer 105 are formed. Then, light 107 is emitted from the other surface of the second substrate 111 (see FIG. 18C). The light 107 is reflected by the reflection layer 102 and absorbed by the light absorption layer 103. Heat is generated from the light absorbed in the light absorption layer 103, and the material of the material layer 104 on the light absorption layer 103 is sublimated by this heat. The material of the material layer 104 over the reflective layer 102 remains on the reflective layer 102 without being sublimated because the light 107 is reflected by the reflective layer 102 and heat is blocked by the heat insulating layer 109.

  By irradiation with light 107, the material of the material layer 104 over the light absorption layer 103 is sublimated, so that the mixed layer 108 is formed over the second substrate 111. The material of the material layer 104 over the reflective layer 102 is not sublimated, and the mixed layer 108 is not formed in the region of the second substrate 111 corresponding to the reflective layer 102 (see FIG. 18D).

[Embodiment 2]
In this embodiment, a method for manufacturing a light-emitting device using the method for manufacturing a mixed layer described in Embodiment 1 is described with reference to FIGS. 13A to 13C and FIGS. C), FIGS. 15A to 15D, and FIGS. 16A to 16C.

  First, based on Embodiment Mode 1, a manufacturing process up to the manufacturing of the cap layer 105 illustrated in FIGS. 2A to 2B is performed.

  An electrode 131 is formed on the substrate 111. The electrode 131 serves as one of an anode and a cathode of the light emitting device.

  In a light-emitting device, one or both of an anode and a cathode needs to be formed using a light-transmitting conductive film. When a light-transmitting conductive film is formed under an organic material layer including a light-emitting layer and a light-shielding conductive film is formed over the organic material layer, the light-emitting device is a bottom emission light-emitting device. . On the other hand, in the case of forming a light-shielding conductive film under the organic layer including the light-emitting layer of the anode or the cathode and a light-transmitting conductive film over the organic layer, the light-emitting device emits light from the top. It becomes a device. In the case where both the anode and the cathode are formed using a light-transmitting conductive film, the light emitting device is a dual emission light emitting device.

  As a material of a light-transmitting anode, indium oxide (In 2 O 3), indium oxide-tin oxide alloy (In 2 O 3 —SnO 2; Indium Tin Oxide (ITO)), indium oxide-tin oxide containing silicon or silicon oxide, indium oxide -Zinc oxide (IZO), indium oxide containing tungsten oxide and zinc oxide, indium oxide zinc oxide alloy (In2O3-ZnO), zinc oxide (ZnO), and further increase the transmittance and conductivity of visible light Therefore, a conductive metal oxide film such as zinc oxide (ZnO: Ga) to which gallium (Ga) is added can be used.

  These materials may be formed using a sputtering method, a vacuum evaporation method, a sol-gel method, or the like.

  For example, indium oxide-zinc oxide (IZO) can be formed by a sputtering method using a target in which 1 to 20 wt% of zinc oxide is added to indium oxide. Further, indium oxide containing tungsten oxide and zinc oxide can be formed by a sputtering method using a target containing 0.5 to 5 wt% tungsten oxide and 0.1 to 1 wt% zinc oxide with respect to indium oxide. it can.

  In the case of forming a light-transmitting cathode, an ultra-thin film of a material having a low work function such as aluminum is used, or a laminated structure of a thin film of such a substance and a light-transmitting conductive film as described above is used. It can be manufactured by using.

  In addition, by providing an electron injection layer between the cathode and the electron transport layer described later, various translucency such as indium oxide-tin oxide containing ITO, silicon, or silicon oxide, regardless of the size of the work function. An electroconductive material having the above can be used as the cathode. These conductive materials can be formed by a sputtering method, an inkjet method, a spin coating method, or the like.

  When a light-shielding conductive film is used as the cathode, a metal, an alloy, an electrically conductive compound, a mixture thereof, or the like having a low work function (specifically, 3.8 eV or less) can be used. Specific examples of such a cathode material include elements belonging to Group 1 or Group 2 of the periodic table of elements, that is, alkali metals such as lithium (Li) and cesium (Cs), and magnesium (Mg) and calcium (Ca ), Alkaline earth metals such as strontium (Sr), and alloys containing these (MgAg, AlLi), rare earth metals such as europium (Eu), ytterbium (Yb), and alloys containing these.

  In the case of using a light-shielding conductive film as an anode, it is preferable to use a metal, an alloy, a conductive compound, a mixture thereof, or the like having a high work function (specifically, 4.0 eV or more).

  For example, gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd ) Or a nitride of a metal material (for example, titanium nitride). Further, by providing the above-described composite material in contact with the anode, the material of the electrode can be selected regardless of the work function.

  As the substrate 111, a glass substrate, a quartz substrate, a semiconductor substrate, a ceramic substrate, or the like may be used. However, in the case of manufacturing a bottom emission light emitting device and a dual emission light emitting device, the substrate 111 also needs to be a light-transmitting substrate. A glass substrate or a quartz substrate may be used as such a light-transmitting substrate.

  A partition wall 132 is formed on the substrate 111 so as to overlap with an end portion of the electrode 131. The partition wall 132 is formed to separate the mixed layer 108 for each pixel, and an inorganic insulating material or an organic insulating material can be used.

  As the inorganic material, for example, any one of silicon oxide, silicon nitride, silicon oxide containing nitrogen, and diamond-like carbon (DLC), or a stacked structure of two or more can be used. As the organic material, any one of polyimide, acrylic, polyamide, polyimide amide, resist, benzocyclobutene, and siloxane, or a stacked structure of two or more may be used.

  Siloxane has a skeletal structure composed of a bond of silicon (Si) and oxygen (O) and contains at least hydrogen as a substituent, or at least one of fluorine, an alkyl group, and aromatic hydrocarbon as a substituent. A polymer material having a seed is formed as a starting material. Further, a fluoro group may be used as a substituent, and an organic group containing at least hydrogen and a fluoro group may be used as a substituent.

  The surface of the substrate 101 on which the cap layer 105 is formed faces the surface of the substrate 111 on which the partition wall 132 is formed, and light 107 is irradiated from the surface of the substrate 101 on which the cap layer 105 is not formed (FIG. 13). (See (A)).

  By irradiation with light 107, the material of the material layer 104 over the light absorption layer 103 is sublimated, so that the mixed layer 108 is formed over the electrode 131. The material of the material layer 104 over the reflective layer 102 is not sublimated (see FIG. 13B).

  Next, an electrode 133 which is the other of the anode and the cathode is formed over the mixed layer 108 (see FIG. 13C). As described above, a light-emitting device having a light-emitting layer sandwiched between an anode and a cathode can be manufactured.

  FIGS. 14A to 14C, FIGS. 15A to 15D, and FIGS. 15A to 15D each illustrate the case where three types of light emitting layers having different emission colors are formed at different locations on the substrate 111. This will be described with reference to FIGS. 16 (A) to 16 (C).

  First, three substrates 101 illustrated in FIG. 2A in Embodiment 1 are prepared. However, each substrate is provided with a material layer containing a material for forming a light emitting layer having a different emission color.

  Specifically, a substrate 101R having a material layer 104R for forming a mixed layer 108R that exhibits red light emission, a substrate 101G having a material layer 104G for forming a mixed layer 108G that exhibits green light emission, and a blue light emission. A substrate 101B having a material layer 104B for forming the mixed layer 108B shown is prepared.

  On the substrate 101R, the reflective layer 102R is formed corresponding to the region where the mixed layer 108R is not formed, and the reflective layer 102R is not formed in the region corresponding to the region where the mixed layer 108R is formed. Since the light absorption layer 103R is formed over the reflective layer 102R, only the light absorption layer 103R is formed in a region corresponding to the region where the mixed layer 108R is formed over the substrate 101R.

  In addition, on the substrate 101G, the reflective layer 102G is formed corresponding to the region where the mixed layer 108G is not formed, and the reflective layer 102G is not formed in the region corresponding to the region where the mixed layer 108G is formed. Since the light absorption layer 103G is formed over the reflective layer 102G, only the light absorption layer 103G is formed in a region corresponding to the region where the mixed layer 108G is formed over the substrate 101G.

  Further, on the substrate 101B, the reflective layer 102B is formed corresponding to the region where the mixed layer 108B is not formed, and the reflective layer 102B is not formed in the region corresponding to the region where the mixed layer 108B is formed. Since the light absorption layer 103B is formed over the reflective layer 102B, only the light absorption layer 103B is formed in a region corresponding to the region where the mixed layer 108B is formed over the substrate 101B.

  Hereinafter, an example in which the mixed layer 108R corresponding to the red pixel R, the mixed layer 108G corresponding to the green pixel G, and the mixed layer 108B corresponding to the blue pixel B are formed in this order will be described. The order is not limited to the following.

  First, the surface of the substrate 101R on which the cap layer 105 is formed and the surface of the substrate 111 on which the partition wall 132 is formed are opposed to each other, and light 107 from the surface of the substrate 101R on which the light absorption layer 103R and the material layer 104R are not formed. (See FIG. 14A).

  The material layer 104R is heated by absorbing the light 107 irradiated by the light absorption layer 103R. Thus, the material contained in the material layer 104R is sublimated, and the mixed layer 108R is formed over the electrode 131 corresponding to the red pixel R formed over the substrate 111 (see FIG. 14B).

  After the mixed layer 108R is formed, the substrate 101R is moved to a place away from the substrate 111.

  Next, the surface of the substrate 101G where the cap layer 105 is formed faces the surface of the substrate 111 where the partition wall 132 is formed, and light is emitted from the surface of the substrate 101G where the light absorption layer 103G and the material layer 104G are not formed. 107 is irradiated (see FIG. 14C).

  Note that the material layer 104G formed over the substrate 101G is formed at a position shifted by one pixel from the material layer 104R formed over the substrate 101R.

  The light absorbing layer 103G absorbs the irradiated light 107, whereby the material layer 104G is heated. Accordingly, the material included in the material layer 104G is sublimated, and the mixed layer 108G is formed over the electrode 131 corresponding to the green pixel G formed over the substrate 111 (see FIG. 15A).

  After the mixed layer 108G is formed, the substrate 101G is moved to a place away from the substrate 111.

  Next, the surface of the substrate 101B where the cap layer 105 is formed faces the surface of the substrate 111 where the partition wall 132 is formed, and light is emitted from the surface of the substrate 101B where the light absorption layer 103B and the material layer 104B are not formed. 107 is irradiated (see FIG. 15B).

  Note that the material layer 104B formed over the substrate 101B is formed at a position shifted by two pixels from the material layer 104R formed over the substrate 101R.

  The material layer 104B is heated by absorbing the light 107 irradiated by the light absorption layer 103B. Accordingly, the material included in the material layer 104B is sublimated, and the mixed layer 108B is formed over the electrode 131 corresponding to the blue pixel B formed over the substrate 111 (see FIG. 15C).

  After the mixed layer 108B is formed, the substrate 101B is moved to a place away from the substrate 111.

  Next, an electrode 133 which is the other of the anode and the cathode is formed over each of the mixed layer 108R, the mixed layer 108G, and the mixed layer 108B (see FIG. 15D).

  As described above, a light-emitting device capable of full color display can be formed by forming light-emitting layers having different emission colors over the same substrate.

  The shape and arrangement method of the mixed layer 108R, the mixed layer 108G, and the mixed layer 108B will be described with reference to FIGS.

  16A and 16B are examples in which the shapes of the mixed layer 108R, the mixed layer 108G, and the mixed layer 108B are rectangular. FIG. 16A shows an example in which light emitting layers having the same light emission color are formed continuously (in a so-called line shape) so as to be adjacent to each other. On the other hand, FIG. 16B shows an example in which the light emitting layers having the same emission color are formed so as not to be adjacent to each other.

  Further, as shown in FIG. 16C, the shapes of the mixed layer 108R, the mixed layer 108G, and the mixed layer 108B may be polygons, for example, hexagons. In FIG. 16C, the light emitting layers having the same light emission color are arranged so as not to be adjacent to each other.

  As described above, a full-color light emitting device including a light emitting layer that emits red light, a light emitting layer that emits green light, and a light emitting layer that emits blue light sandwiched between an anode and a cathode can be manufactured.

[Embodiment 3]
In this embodiment, a method for manufacturing a light-emitting device in which a carrier transport layer and a carrier injection layer are formed in addition to the light-emitting layer will be described with reference to FIGS.

  First, based on Embodiment Mode 1 and Embodiment Mode 2, an electrode 131 and a partition wall 132 are formed over a substrate 111 (see FIG. 17A).

  In the case where the electrode 131 is an anode, the electrode 133 may be formed over the electrode 131 as a hole injection layer, a hole transport layer, a mixed layer 108, an electron transport layer, an electron injection layer, and a cathode. In the case where the electrode 131 is a cathode, the electrode 133 may be formed over the electrode 131 as an electron injection layer, an electron transport layer, a mixed layer 108, a hole transport layer, a hole injection layer, and an anode.

  In this embodiment mode, the electrode 131 is an anode, the electrode 133 is a cathode, and the electrode 131, the hole injection layer 141, the hole transport layer 142, the mixed layer 108, the electron transport layer 143, the electron injection layer 144, and the electrode 133 are stacked. Thus, a light emitting device is manufactured.

  A hole injection layer 141 and a hole transport layer 142 are formed over the electrode 131 in a region surrounded by adjacent partition walls 132 (see FIG. 17B).

  For example, for the hole injection layer 141, molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, manganese oxide, or the like can be used. In addition, phthalocyanine compounds such as phthalocyanine (abbreviation: H2Pc) and copper phthalocyanine (abbreviation: CuPc), or poly (3,4-ethylenedioxythiophene) / poly (styrenesulfonic acid) (PEDOT / PSS) The hole injection layer can also be formed by a polymer or the like.

  As the hole-injecting layer 141, a layer containing a substance having a high hole-transport property and a substance showing an electron-accepting property can be used. A layer including a substance having a high hole-transport property and a substance having an electron-accepting property has a high carrier density and an excellent hole-injection property. In addition, by using a layer containing a substance having a high hole transporting property and a substance showing an electron accepting property as a hole injection layer in contact with the electrode functioning as the anode, the work function of the electrode material functioning as the anode can be reduced. Regardless, various metals, alloys, electrically conductive compounds, mixtures thereof, and the like can be used.

  The layer containing a substance having a high hole-transport property and a substance having an electron-accepting property includes, for example, a material layer in which a layer containing a substance having a high hole-transport property and a layer containing a substance having an electron-accepting property are stacked. It can be formed by using a deposition substrate.

  As a substance having an electron accepting property used for the hole injecting layer 141, 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloranil, or the like can be used. Can be mentioned. Moreover, a transition metal oxide can be mentioned. In addition, oxides of metals belonging to Groups 4 to 8 in the periodic table can be given. Specifically, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, and rhenium oxide are preferable because of their high electron accepting properties. Among these, molybdenum oxide is especially preferable because it is stable in the air, has a low hygroscopic property, and is easy to handle.

  As the substance having a high hole-transport property used for the hole-injection layer 141, various compounds such as aromatic amine compounds, carbazole derivatives, aromatic hydrocarbons, and high molecular compounds (oligomers, dendrimers, polymers, and the like) can be used. it can. Note that the substance having a high hole-transport property used for the hole-injection layer is preferably a substance having a hole mobility of 10 −6 cm 2 / Vs or more. Note that other than these substances, any substance that has a property of transporting more holes than electrons may be used. Hereinafter, substances having a high hole-transport property that can be used for the hole-injection layer 141 are specifically listed.

  For example, as an aromatic amine compound that can be used for the hole injection layer 141, for example, 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (abbreviation: NPB), N, N′-bis (3-methylphenyl) -N, N′-diphenyl- [1,1′-biphenyl] -4,4′-diamine (abbreviation: TPD), 4,4 ′, 4 ″ -tris ( N, N-diphenylamino) triphenylamine (abbreviation: TDATA), 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine (abbreviation: MTDATA), 4,4′-bis [N- (spiro-9,9′-bifluoren-2-yl) -N-phenylamino] biphenyl (abbreviation: BSPB) or the like can be used. N, N′-bis (4-methylphenyl) (p-tolyl) -N, N′-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4′-bis [N- (4-diphenyl) Aminophenyl) -N-phenylamino] biphenyl (abbreviation: DPAB), 4,4′-bis (N- {4- [N ′-(3-methylphenyl) -N′-phenylamino] phenyl} -N— Phenylamino) biphenyl (abbreviation: DNTPD), 1,3,5-tris [N- (4-diphenylaminophenyl) -N-phenylamino] benzene (abbreviation: DPA3B), and the like.

  As a carbazole derivative that can be used for the hole-injection layer 141, specifically, 3- [N- (9-phenylcarbazol-3-yl) -N-phenylamino] -9-phenylcarbazole (abbreviation: PCzPCA1) ), 3,6-bis [N- (9-phenylcarbazol-3-yl) -N-phenylamino] -9-phenylcarbazole (abbreviation: PCzPCA2), 3- [N- (1-naphthyl) -N- (9-phenylcarbazol-3-yl) amino] -9-phenylcarbazole (abbreviation: PCzPCN1) and the like can be given.

  Examples of the carbazole derivative that can be used for the hole-injection layer 141 include 4,4′-di (N-carbazolyl) biphenyl (abbreviation: CBP), 1,3,5-tris [4- (N-carbazolyl). Phenyl] benzene (abbreviation: TCPB), 9- [4- (10-phenyl-9-anthryl) phenyl] -9H-carbazole (abbreviation: CzPA), 1,4-bis [4- (N-carbazolyl) phenyl] -2,3,5,6-tetraphenylbenzene and the like can be used.

  Examples of aromatic hydrocarbons that can be used for the hole injection layer 141 include 2-tert-butyl-9,10-di (2-naphthyl) anthracene (abbreviation: t-BuDNA), 2-tert- Butyl-9,10-di (1-naphthyl) anthracene, 9,10-bis (3,5-diphenylphenyl) anthracene (abbreviation: DPPA), 2-tert-butyl-9,10-bis (4-phenylphenyl) ) Anthracene (abbreviation: t-BuDBA), 9,10-di (2-naphthyl) anthracene (abbreviation: DNA), 9,10-diphenylanthracene (abbreviation: DPAnth), 2-tert-butylanthracene (abbreviation: t-) BuAnth), 9,10-bis (4-methyl-1-naphthyl) anthracene (abbreviation: DMNA), 9,10-bis [2 (1-naphthyl) phenyl] -2-tert-butyl-anthracene, 9,10-bis [2- (1-naphthyl) phenyl] anthracene, 2,3,6,7-tetramethyl-9,10-di ( 1-naphthyl) anthracene, 2,3,6,7-tetramethyl-9,10-di (2-naphthyl) anthracene, 9,9′-bianthryl, 10,10′-diphenyl-9,9′-bianthryl, 10,10′-bis (2-phenylphenyl) -9,9′-bianthryl, 10,10′-bis [(2,3,4,5,6-pentaphenyl) phenyl] -9,9′-bianthryl , Anthracene, tetracene, rubrene, perylene, 2,5,8,11-tetra (tert-butyl) perylene, and the like. In addition, pentacene, coronene, and the like can also be used. Thus, it is more preferable to use an aromatic hydrocarbon having a hole mobility of 1 × 10 −6 cm 2 / Vs or more and having 14 to 42 carbon atoms.

  Note that the aromatic hydrocarbon which can be used for the hole injection layer 141 may have a vinyl skeleton. As the aromatic hydrocarbon having a vinyl group, for example, 4,4′-bis (2,2-diphenylvinyl) biphenyl (abbreviation: DPVBi), 9,10-bis [4- (2,2- Diphenylvinyl) phenyl] anthracene (abbreviation: DPVPA) and the like.

  The hole-injecting layer 141 can be formed by using a deposition substrate including a material layer in which a layer containing a substance having a high hole-transport property and a layer containing an electron-accepting substance are stacked. it can. In the case where a metal oxide is used as the substance exhibiting electron accepting properties, it is preferable to form a layer containing a metal oxide after forming a layer containing a substance having a high hole-transport property over the electrode 131. This is because a metal oxide often has a higher decomposition temperature or vapor deposition temperature than a substance having a high hole-transport property. By using an evaporation source having such a configuration, a substance having a high hole transporting property and a metal oxide can be efficiently sublimated. In addition, local concentration deviation can be suppressed in a film formed by vapor deposition. In addition, there are few types of solvents that dissolve or disperse both the substance having a high hole transporting property and the metal oxide, and it is difficult to form a mixed solution. Therefore, it is difficult to directly form the mixed layer using a wet method. However, by using the deposition substrate deposition method of this embodiment, a mixed layer including a substance having a high hole-transport property and a metal oxide can be easily formed.

  In addition, a layer including a substance having a high hole-transport property and a substance having an electron-accepting property has excellent hole-transport properties as well as a hole-injection property. It may be used as a transport layer.

  The hole transport layer 142 is a layer containing a substance having a high hole transport property, and examples of the substance having a high hole transport property include 4,4′-bis [N- (1-naphthyl) -N. -Phenylamino] biphenyl (abbreviation: NPB or α-NPD) and N, N′-bis (3-methylphenyl) -N, N′-diphenyl- [1,1′-biphenyl] -4,4′-diamine (Abbreviation: TPD), 4,4 ′, 4 ″ -tris (N, N-diphenylamino) triphenylamine (abbreviation: TDATA), 4,4 ′, 4 ″ -tris [N- (3-methyl Phenyl) -N-phenylamino] triphenylamine (abbreviation: MTDATA), 4,4′-bis [N- (spiro-9,9′-bifluoren-2-yl) -N-phenylamino] biphenyl (abbreviation: Aromatic amination such as BSPB) It can be used things like. The substances described here are mainly substances having a hole mobility of 10 −6 cm 2 / Vs or higher. Note that other than these substances, any substance that has a property of transporting more holes than electrons may be used. Note that the layer containing a substance having a high hole-transport property is not limited to a single layer, and two or more layers containing the above substances may be stacked.

  After forming the hole transport layer 142, the mixed layer 108 is formed based on Embodiments 1 and 2 (see FIG. 17C). Based on Embodiment Mode 2, a mixed layer 108R that emits red light emission color, a mixed layer 108G that emits green light emission color, and a mixed layer 108B that emits blue light emission color may be formed.

  Next, an electron-transport layer 143 and an electron-injection layer 144 are formed over the mixed layer 108, and an electrode 133 is formed over the electron-injection layer 144 (see FIG. 17D).

  The electron-transport layer 143 is a layer containing a substance having a high electron-transport property. For example, tris (8-quinolinolato) aluminum (abbreviation: Alq), tris (4-methyl-8-quinolinolato) aluminum (abbreviation: Almq3), A quinoline skeleton or a benzoquinoline skeleton such as bis (10-hydroxybenzo [h] quinolinato) beryllium (abbreviation: BeBq2), bis (2-methyl-8-quinolinolato) (4-phenylphenolato) aluminum (abbreviation: BAlq) The metal complex etc. which have can be used. In addition, bis [2- (2-hydroxyphenyl) benzoxazolate] zinc (abbreviation: Zn (BOX) 2), bis [2- (2-hydroxyphenyl) benzothiazolate] zinc (abbreviation: Zn (BTZ)) A metal complex having an oxazole-based or thiazole-based ligand such as 2) can also be used. In addition to metal complexes, 2- (4-biphenylyl) -5- (4-tert-butylphenyl) -1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis [5 -(P-tert-butylphenyl) -1,3,4-oxadiazol-2-yl] benzene (abbreviation: OXD-7), 3- (4-biphenylyl) -4-phenyl-5- (4- tert-Butylphenyl) -1,2,4-triazole (abbreviation: TAZ01) bathophenanthroline (abbreviation: BPhen), bathocuproin (abbreviation: BCP), and the like can also be used. The substances mentioned here are mainly substances having an electron mobility of 10 −6 cm 2 / Vs or higher. Note that other than the above substances, any substance that has a property of transporting more electrons than holes may be used for the electron-transport layer. Further, the electron-transport layer is not limited to a single layer, and two or more layers including the above substances may be stacked.

  As the electron injection layer 144, an alkali metal compound such as lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF2), or an alkaline earth metal compound can be used. Further, a layer in which a substance having an electron transporting property and an alkali metal or an alkaline earth metal are combined can also be used. For example, Alq containing magnesium (Mg) can be used. Note that it is more preferable to use a layer in which an electron transporting substance is combined with an alkali metal or an alkaline earth metal as the electron injection layer because electron injection from the electrode 133 which is a cathode occurs efficiently.

  The hole injection layer, the hole transport layer, the electron transport layer, and the electron injection layer may be formed as necessary, and all of them are not necessarily formed.

[Embodiment 4]
As electronic devices to which the light-emitting device described in any of Embodiments 1 to 3 is applied, a television, a video camera, a digital camera, a goggle-type display (head-mounted display), a navigation system, a sound reproduction device (car audio, audio) Components, etc.), notebook computers, game machines, portable information terminals (mobile computers, mobile phones, portable game machines, electronic books, etc.), and image playback devices (specifically digital video discs (DVD)) equipped with recording media For example, a device provided with a display device capable of reproducing the recording medium and displaying the image thereof, and a lighting fixture. Specific examples of these electronic devices are illustrated in FIGS. 7A to 7E and FIGS. 8A to 8C.

  FIG. 7A illustrates a display device, which includes a housing 201, a support base 202, a display portion 203, a speaker portion 204, a video input terminal 205, and the like. The display device 203 is manufactured using the light-emitting device formed using any of Embodiment Modes 1 to 3. The display device includes all information display devices such as a personal computer, a TV broadcast reception, and an advertisement display.

  FIG. 7B illustrates a computer, which includes a main body 211, a housing 212, a display portion 213, a keyboard 214, an external connection port 215, a mouse 216, and the like. Note that the computer is manufactured by using the light-emitting device formed by using Embodiment Modes 1 to 3 for the display portion 213.

  FIG. 7C illustrates a video camera, which includes a main body 221, a display portion 222, a housing 223, an external connection port 224, a remote control receiving portion 225, an image receiving portion 226, a battery 227, an audio input portion 228, operation keys 229, and an eyepiece. Part 231 and the like. Note that the video camera is manufactured by using the light-emitting device formed using Embodiment Modes 1 to 3 for the display portion 222.

  FIG. 7D illustrates a table lamp, which includes a lighting unit 241, an umbrella 242, a variable arm 243, a column 244, a table 245, and a power source 246. Note that the desk lamp is manufactured by using the light-emitting device formed by using Embodiment Modes 1 to 3 for the lighting unit 241. The lighting fixture includes a ceiling-fixed lighting fixture or a wall-mounted lighting fixture.

  Here, FIG. 7E illustrates a mobile phone, which includes a main body 251, a housing 252, a display portion 253, a sound input portion 254, a sound output portion 255, operation keys 256, an external connection port 257, an antenna 258, and the like. Note that the cellular phone is manufactured using the light-emitting device formed using Embodiment Modes 1 to 3 for the display portion 253.

  8A is also a mobile phone, FIG. 8A is a front view, FIG. 8B is a rear view, and FIG. 8C is a development view. The main body 301 is a so-called smartphone that has both functions of a telephone and a portable information terminal, has a built-in computer, and can perform various data processing in addition to voice calls.

  The main body 301 includes two housings, a housing 302 and a housing 303. The housing 302 includes a display portion 304, a speaker 305, a microphone 306, operation keys 307, a pointing device 308, a camera lens 309, an external connection terminal 310, an earphone terminal 311 and the like, and the housing 303 includes a keyboard 312, An external memory slot 313, a camera lens 314, a light 315, and the like are provided. An antenna is built in the housing 302.

  In addition to the above structure, a non-contact IC chip, a small recording device, or the like may be incorporated.

  The display unit 304 can incorporate the display device described in the above embodiment, and the display direction changes appropriately depending on the usage pattern. Since the camera lens 309 is provided on the same surface as the display portion 304, a videophone can be used. Further, the display unit 304 can be used as a viewfinder, and still images and moving images can be taken with the camera lens 314 and the light 315. The speaker 305 and the microphone 306 are not limited to voice calls and can be used for videophone calls, recording, playback, and the like.

  With the operation key 307, making and receiving calls, inputting simple information such as e-mail, scrolling the screen, moving the cursor, and the like are possible. Further, the housing 302 and the housing 303 (FIG. 8A) which are overlapped with each other are slid and developed as illustrated in FIG. 8C, so that the portable information terminal can be used. In this case, smooth operation is possible using the keyboard 312 and the pointing device 308. The external connection terminal 310 can be connected to an AC adapter and various cables such as a USB cable, and charging and data communication with a personal computer or the like are possible. Further, a large amount of data can be stored and moved by inserting a recording medium into the external memory slot 313.

  In addition to the above functions, an infrared communication function, a television reception function, or the like may be provided.

  Note that the above-described mobile phone is manufactured by using the light-emitting device formed by using Embodiment Modes 1 to 3 for the display portion 304.

  As described above, an electronic device or a lighting fixture can be obtained by using the light-emitting device described in any of Embodiments 1 to 3. As described above, the applicable range of the light-emitting device is so wide that the light-emitting device can be applied to electronic devices in various fields.

101 substrate 101B substrate 101G substrate 101R substrate 102 reflecting layer 102B reflecting layer 102G reflecting layer 102R reflecting layer 103 light absorbing layer 103B light absorbing layer 103G light absorbing layer 103R light absorbing layer 104 material layer 104B material layer 104G material layer 104R material layer 105 cap Layer 107 light 108 mixed layer 108B mixed layer 108G mixed layer 108R mixed layer 109 heat insulation layer 111 substrate 121 surface 122 layer 123 layer 124 layer 125 layer 127 wire 131 electrode 132 partition 133 electrode 141 hole injection layer 142 hole transport layer 143 electron Transport layer 144 Electron injection layer 201 Housing 202 Support base 203 Display unit 204 Speaker unit 205 Video input terminal 211 Main body 212 Housing 213 Display unit 214 Keyboard 215 External connection port 216 Mouse 221 Main unit 222 Display unit 23 Housing 224 External connection port 225 Remote control receiving unit 226 Image receiving unit 227 Battery 228 Audio input unit 229 Operation key 231 Eyepiece unit 241 Illuminating unit 242 Umbrella 243 Variable arm 244 Post 245 Base 246 Power supply 251 Main body 252 Housing 253 Display unit 254 Audio input unit 255 Audio output unit 256 Operation key 257 External connection port 258 Antenna 301 Main body 302 Case 303 Case 304 Display unit 305 Speaker 306 Microphone 307 Operation key 308 Pointing device 309 Camera lens 310 External connection terminal 311 Earphone terminal 312 Keyboard 313 External memory slot 314 Camera lens 315 Light

Claims (6)

Forming a light absorption layer on the first surface of the first substrate;
On the light absorption layer, a material layer including a host and a guest material composed of two or more different sublimation temperatures is formed,
On the material layer, a cap layer made of a material having a higher sublimation temperature than the material layer is formed,
The first surface of the second substrate on which the anode is formed is opposed to the first surface of the first substrate;
By irradiating light from a second surface opposite to the first surface of the first substrate, heating the material layer to a sublimation temperature of the material layer, and sublimating the material layer, The cap layer remains above the light absorption layer of the first substrate, and a mixed layer in which the two or more types of host and guest materials are mixed is formed on the first surface of the second substrate. Membrane
A method for manufacturing a light-emitting device, comprising forming a cathode on the mixed layer. Forming a reflective layer in a first region on the first surface of the first substrate;
Forming a light absorbing layer on the reflective layer and on the second region on the first substrate where the reflective layer is not formed;
On the light absorption layer, a material layer including a host and a guest material composed of two or more different sublimation temperatures is formed,
On the material layer, a cap layer made of a material having a higher sublimation temperature than the material layer is formed,
The first surface of the second substrate on which the anode is formed is opposed to the first surface of the first substrate;
The material layer on the light absorption layer on the second region is heated to the sublimation temperature of the material layer by irradiating light from a second surface opposite to the first surface of the first substrate. Then, by sublimating the material layer, the cap layer remains above the light absorption layer of the first substrate, and the two or more types of hosts are formed on the first surface of the second substrate. And a mixed layer in which the guest material is mixed,
A method for manufacturing a light-emitting device, comprising forming a cathode on the mixed layer. In claim 1 or claim 2,
The method for manufacturing a light-emitting device, wherein the cap layer includes one or more of aluminum, silver, calcium fluoride, and lithium fluoride (LiF). In any one of Claims 1 thru | or 3,
The light absorption layer includes any one or more of titanium nitride, tantalum nitride, molybdenum nitride, tungsten nitride, chromium nitride, manganese nitride, molybdenum, titanium, tungsten, and carbon, or a light emitting device Manufacturing method. In claim 2,
The reflective layer is any one of aluminum, silver, gold, platinum, copper, an aluminum-titanium alloy, an aluminum-neodymium alloy, an alloy containing aluminum such as an aluminum-titanium alloy, and an alloy containing silver such as a silver-neodymium alloy, Alternatively, a method for manufacturing a light-emitting device including two or more. In any one of Claims 1 thru | or 5,
Of the material layers containing the two or more types of host and guest materials, the host material is 9- [4- (10-phenyl-9-anthryl) phenyl] -9H-carbazole (abbreviation: CzPA),
Among the material layers containing two or more kinds of host and guest materials, the guest material is N- (9,10-diphenyl-2-anthryl) -N, 9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCAPA A method for manufacturing a light-emitting device.

Images