JP2020141084A - Stacked light emitting and receiving element and electronic device equipped with the same - Google Patents

Abstract

To provide a light-emitting light-receiving element that maximizes light-emitting brightness and light-receiving sensitivity, and a reflection-type pulse oximeter that eliminates the hassle of a subject, such as being able to be used by being wrapped around the wrist instead of being sandwiched between fingertips.SOLUTION: A laminated light emitting and receiving element according to the present invention in which a planar light emitting element and a light receiving element are laminated, and the light receiving element receives reflected light emitted by the light emitting element.SELECTED DRAWING: Figure 2

Description

The present invention relates to a laminated light emitting and receiving element and an electronic device including the same. More specifically, the present invention relates to a light emitting and receiving element that maximizes light emitting brightness and light receiving sensitivity, and a reflective pulse oximeter that eliminates the annoyance of the subject, such as being able to be used by wrapping it around the wrist instead of sandwiching it between fingertips.

The pulse oximeter that can measure blood oxygen concentration and pulse is generally a transmission type, and the type that is sandwiched between fingertips is the mainstream. Since a light emitting diode (LED) is generally used as the light source, a large block is always worn on the fingertip, and the subject feels a great deal of trouble. On the other hand, an organic light emitting diode (OLED) is used as a light emitting light source that can be thinned, and an organic photoelectric conversion element (OPC) is used as a light receiving sensor. A technique has been proposed in which an organic photo detector (OPD) is used and arranged side by side on the same substrate (see, for example, Patent Document 1). However, since a plurality of devices are arranged on the same plane, the gap between the devices does not function, and the emission brightness and the light reception sensitivity are limited.

Further, as a pulse oximeter, there has been a proposal to fabricate an OLED on a transmissive flexible substrate, wrap it around a finger, and place a sensor on the opposite side of the finger (see, for example, Non-Patent Document 1). There was a problem such as not being able to deal with the difference.

U.S. Patent Application Publication No. 2017/0156651

Nikkei Electronics (issued December 13, 2014)

The present invention has been made in view of the above problems and situations, and the problem to be solved is to use a light emitting and receiving element that maximizes the light emitting brightness and the light receiving sensitivity by wrapping it around a wrist or the like instead of sandwiching it between fingertips. It is to provide a reflective pulse oximeter that eliminates the hassle of the subject, such as being able to do it.

In the process of investigating the cause of the above problem in order to solve the above problem, the present inventor has a laminated type light emitting and receiving device in which a light emitting element and a light receiving element that receives the reflected light of the light emitted by the light emitting element are laminated. It has been found that a light-emitting light-receiving element that maximizes the light-emitting brightness and the light-receiving sensitivity and a reflection-type pulse oximeter that eliminates the hassle of the subject can be obtained.

That is, the above problem according to the present invention is solved by the following means.

1. 1. It is a laminated light emitting and receiving element in which a planar light emitting element and a light receiving element are laminated.
The light receiving element is a stacked light emitting and receiving element, characterized in that it receives the reflected light of the light emitted by the light emitting element.

2. 2. The stacked light emitting and receiving element according to item 1, wherein the light emitting element emits light having a plurality of different wavelengths.

3. 3. The stacked light emitting / receiving element according to the first or second item, wherein the light emitting element is arranged on the light emitting surface side.

4. The laminated light emitting and receiving device according to any one of items 1 to 3, wherein the light transmitting substrate, the light emitting element, the intermediate insulating layer, the light receiving element, and the sealing layer are formed in this order. element.

5. The laminated light-emitting light-receiving element according to item 1 or 2, wherein the light-transmitting substrate, the light-receiving element, the intermediate insulating layer, the light-emitting element, and the sealing layer are configured in this order.

6. The laminated light emitting and receiving device according to any one of items 1 to 3, wherein the substrate, a light receiving element, an intermediate insulating layer, a light emitting element, and a light transmitting sealing layer are formed in this order. element.

7. An electronic device comprising the stacked light emitting and receiving element according to any one of items 1 to 6.

8. The electronic device according to item 7, wherein the electronic device is a reflective pulse oximeter.

By the above means of the present invention, a light emitting and receiving element that maximizes the light emitting brightness and the light receiving sensitivity, and a reflective pulse oximeter that eliminates the troublesomeness of the subject, such as being able to be used by wrapping it around the wrist instead of sandwiching it between fingertips. Can be provided.

Although the mechanism of expression or mechanism of action of the effect of the present invention has not been clarified, it is inferred as follows.

The laminated light emitting / receiving element of the present invention is characterized in that it is a light emitting / receiving element in which a light emitting element and a light receiving element that receives reflected light of light emitted by the light emitting element are laminated.

When a plurality of devices are arranged on the same plane as in the light emitting / receiving element disclosed in Patent Document 1, the gap portion between the devices does not function, and the light emitting brightness and the light receiving sensitivity are limited. By setting, such a problem is solved. Further, by stacking the OLED and OPV, it becomes easy to optimize the light emitting area and the light receiving area.

Further, in the manufacture of electronic devices, the laminated light emitting / receiving element does not require high alignment accuracy when arranging a plurality of devices on the same plane, and has an advantage that the yield at the time of manufacturing the device is improved. It is presumed that the process will be simplified and the leak level will be improved.

Further, since the reflection type pulse oximeter provided with the laminated light emitting and receiving element of the present invention is not a conventional transmission type, it can be used by wrapping it around a wrist or an arm instead of sandwiching it between fingertips. It is presumed that the annoyance will be eliminated and the wearability will be improved.

Schematic diagram illustrating the arrangement of conventional light emitting and receiving elements Schematic diagram illustrating the arrangement of the stacked light emitting and receiving elements of the present invention (Embodiment 1) Schematic diagram illustrating the arrangement of another laminated light emitting and receiving element of the present invention (Embodiment 2). Schematic diagram for explaining the arrangement of another laminated light emitting and receiving element of the present invention (Embodiment 3). Cross-sectional view showing the configuration of an organic EL element Cross-sectional view showing an example of a multicolor laminated light emitting and receiving element Sectional drawing which shows the structure of an organic photoelectric conversion element Perspective view of a reflective pulse oximeter that can be wrapped around the wrist

The laminated light emitting and receiving element of the present invention is a laminated light emitting and receiving element in which a planar light emitting element and a light receiving element are laminated, and the light receiving element receives the reflected light of the light emitted by the light emitting element. It is characterized by. This feature is a technical feature common to or corresponding to the following embodiments.

In an embodiment of the present invention, it is preferable that the light emitting element emits light having a plurality of different wavelengths from the viewpoint of exhibiting the effect of the present invention, and from the viewpoint of application to a pulse oximeter, red light and green light are used. It is preferable to emit light. Here, red light means light having a peak at an optical wavelength of 600 to 650 nm, and green light means light having a peak at an optical wavelength of 500 to 550 nm.

Further, it is a preferable aspect that the light emitting element is arranged on the light emitting surface side from the viewpoint of maximizing the light emitting brightness.

Therefore, it is preferable that the laminated light emitting and receiving element of the present invention is composed of the translucent substrate, the light emitting element, the intermediate insulating layer, the light receiving element, and the sealing layer in this order.

Further, in the application of maximizing the light receiving sensitivity, the laminated light emitting light receiving element of the present invention is composed of a translucent substrate, a light receiving element, an intermediate insulating layer, a light emitting element and a sealing layer in this order. This is also a preferable layer order. Further, the laminated light emitting / receiving element of the present invention is composed of a substrate, a light receiving element, an intermediate insulating layer, a light emitting element, and a light transmitting sealing layer in this order, and emits light and receives light from the sealing layer side. It may be configured to be.

The electronic device of the present invention is characterized by including the laminated light emitting and receiving element, and it is a preferred embodiment that the electronic device is a reflection type pulse oximeter.

Hereinafter, the present invention, its components, and modes and modes for carrying out the present invention will be described in detail. In the present application, "~" is used to mean that the numerical values described before and after the value are included as the lower limit value and the upper limit value.

<< Outline of the laminated light emitting / receiving element of the present invention >>
The laminated light emitting and receiving element of the present invention is a laminated light emitting and receiving element in which a planar light emitting element and a light receiving element are laminated, and the light receiving element receives the reflected light of the light emitted by the light emitting element. It is characterized by.

[1] Configuration of Stacked Light-emitting Element: Prior to the description of the laminated light-receiving element of the present invention, the arrangement of the light-emitting element described in US Patent Application Publication No. 2017/0156651 which is a conventional example. explain.

<Conventional Embodiment>
FIG. 1 is a schematic view illustrating a conventional light emitting / receiving element arranged adjacently on the same surface. However, the figure is an example and is not limited to this, and the OLED and OPV are shown in a circle, but the figure is not limited to a circle and may be an ellipse, a rectangle or an indeterminate form. Good. Further, the insulating layer or the like can be produced by patterning, but it is omitted in the drawing.

The conventional light emitting / receiving element 10 arranged adjacently on the same surface forms a light transmitting first electrode 2 (for example, an anode) on the light transmissive substrate 1, and is a light emitting element having an organic function on the first electrode 2 (for example, an anode). An OLED 3 composed of layers and a light-reflecting second electrode 4 (for example, a cathode) are formed and a light emitting element is arranged. Next, OPV5, which is a light receiving element and is composed of an organic functional layer, is formed on the first electrode 2 apart from the OLED3. A light-reflecting fourth electrode 7 is formed on the fourth electrode 7 to serve as a light receiving element. In order to prevent current leakage, for example, an insulating layer (not shown) containing SiO ₂ is provided between the OLED 3 and the OPV 5. Then, in order to seal the entire elements, the adhesive layer 8 and the sealing material 9 are used for sealing.

In addition, MAM (Mo (molybdenum) / Al (aluminum) / Mo (molybdenum) is usually connected to the first electrode to the fourth electrode as a take-out electrode (not shown).

With this configuration, the emitted light L1 from the OLED 3 passes through the translucent substrate, is irradiated from the surface of the arm 15 of the subject to the inside of the arm, and the reflected light L2 reflected by the arteries and veins is detected by the OPV5 and is not shown. The oxygen concentration in the subject's blood is measured by a measurement analyzer.

In this configuration, as described above, since a plurality of devices are arranged on the same plane, the gap portion between the devices does not function, and the emission brightness and the light reception sensitivity are limited. Further, in the manufacture of electronic devices, high alignment accuracy is required when arranging a plurality of devices on the same plane, and the yield at the time of manufacturing the element is lowered and the leak level is lowered.

Subsequently, the arrangement of the configuration of the laminated light emitting and receiving element of the present invention will be described with reference to the drawings.

<Embodiment 1 of the laminated light emitting and receiving element of the present invention>
FIG. 2 is a schematic view illustrating the arrangement of the laminated light emitting / receiving element of the present invention. However, the figure is an example and is not limited to this.

FIG. 2A is a view seen from the normal direction with respect to the substrate, and FIG. 2B is a cross-sectional view.

In the laminated light emitting / receiving element 20 of the present invention, a light transmitting first electrode 2 is formed on a light transmissive substrate 1, and a light emitting element OLED 3 and a light reflecting second electrode 4 are formed on the first electrode 2. The light emitting element is arranged. An intermediate insulating layer 11 is formed on the intermediate insulating layer 11, and an OPV 5 which is a light receiving element is formed on the light transmitting third electrode 6 in an area larger than that of the OLED 3. A light-reflecting fourth electrode 7 is formed on the fourth electrode 7 to serve as a light receiving element. Then, in order to seal the entire elements, the adhesive layer 8 and the sealing material 9 are used for sealing.

Similarly, MAM (Mo (molybdenum) / Al (aluminum) / Mo (molybdenum) is usually connected to the first electrode, the second electrode, the third electrode, and the fourth electrode as a take-out electrode (not shown). ).

With this configuration, the emitted light L1 from the OLED 3 passes through the translucent substrate, is irradiated from the surface of the arm 15 of the subject to the inside of the arm, and the reflected light L2 reflected by the arteries and veins is detected by the OPV5 and is not shown. The oxygen concentration in the subject's body is measured by evaluating and calculating with a measurement analyzer.

In this configuration, as described above, since a plurality of devices are stacked, the problem that the gaps between the devices do not function when arranging the plurality of devices on the same plane and the emission brightness and the reception sensitivity are limited is solved. Will be done. Further, since the OLED and the OPV have a laminated structure, it becomes easy to optimize the light emitting area and the light receiving area.

Further, in the manufacture of electronic devices, the laminated laminated light emitting / receiving element does not require high alignment accuracy when arranging a plurality of devices on the same plane, and has an advantage that the yield at the time of manufacturing the element is improved. This simplifies the manufacturing process and improves the leak level.

<Embodiment 2 of the laminated laminated light emitting / receiving element of the present invention>
In the second embodiment, the laminated light emitting and receiving element of the present invention is configured in the order of a translucent substrate, a light receiving element, an intermediate insulating layer, a light emitting element and a sealing layer, and is a modification of the first embodiment. Is.

FIG. 3 is a schematic view illustrating the arrangement of another laminated light emitting / receiving element of the present invention.

FIG. 3A is a view seen from the normal direction with respect to the substrate, and FIG. 3B is a cross-sectional view.

In the laminated light emitting and receiving element 30 of the present invention, a light transmitting third electrode 6 is formed on a light transmitting substrate 1, and an OPV 5 which is a light receiving element and a light reflecting fourth electrode 7 are formed on the third electrode 6. The light receiving element is arranged. An intermediate insulating layer 11 is formed on the intermediate insulating layer 11, and an OLED 3 which is a light emitting element is formed on the light-transmitting first electrode 2 in an area smaller than OPV5. A light-reflecting second electrode 4 is formed on the second electrode 4 to serve as a light emitting element. Then, in order to seal the entire elements, the adhesive layer 8 and the sealing material 9 are used for sealing.

With this configuration, the emitted light L1 from the OLED 3 passes through the translucent substrate and is irradiated from the surface of the subject's arm 15 to the inside of the arm, and the reflected light L2 reflected by the arteries and veins is detected by the OPV and measured and analyzed (not shown). The device measures the oxygen concentration in the subject.

This configuration is a preferred layer order for applications that maximize light receiving sensitivity.

<Embodiment 3 of the laminated light emitting and receiving element of the present invention>
In the third embodiment, the laminated light emitting and receiving element of the present invention is configured in the order of a substrate, a light receiving element, an intermediate insulating layer, a light emitting element, and a light transmitting sealing layer, and is a modification of the first embodiment. Is.

FIG. 4 is a schematic view illustrating the arrangement of another stacked light emitting / receiving element of the present invention.

FIG. 4A is a view seen from the normal direction with respect to the substrate, and FIG. 4B is a cross-sectional view.

In the laminated light emitting and receiving element 40 of the present invention, a light reflecting second electrode 4 is formed on a light opaque substrate 12 when viewed from above, and a light emitting element OLED 3 and a light transmitting first electrode 4 are formed on the second electrode 4. 1 Electrode 2 is formed and a light emitting element is arranged. An intermediate insulating layer 11 is formed on the intermediate insulating layer 11, and OPV5, which is a light receiving element, is formed on the light-reflecting fourth electrode 7 in an area larger than that of the OLED3. A light-transmitting third electrode 6 is formed on the third electrode 6 to serve as a light receiving element. Then, in order to seal the entire elements, the adhesive layer 8 and the light-transmitting sealing material 13 are used for sealing.

With this configuration, the emitted light L1 from the OLED 3 is transmitted through the light-transmitting sealing material 13, and is irradiated from the surface of the subject's arm 15 to the inside of the arm, and the reflected light L2 reflected by the arteries and veins is detected by the OPV5. The oxygen concentration in the subject's body is measured by a measurement analyzer (not shown).

According to this aspect, the selection range of the material of the substrate 12 is increased, and the degree of freedom of the element configuration is increased by using the light-transmitting sealing material 9 made of a material different from that of the substrate.

[2] Light-emitting element The light-emitting element used in the stacked light-emitting element of the present invention is a planar light-emitting element, which is an organic light emitting diode (OLED), which is an organic electroluminescence element (OLED). Organic electroluminescent dimension: also referred to as "OLED" or "organic EL element"), hereinafter referred to as an organic EL element. ) Is preferably used.

FIG. 5 is a cross-sectional view showing the configuration of a typical organic EL element.

The organic EL element 100 includes a base material 101, an anode 102, a hole injection layer 103, a hole transport layer 104, a light emitting layer 105, a block layer 106, an electron transport layer 107, an electron injection layer 108, and a cathode 109 in this order. There is. The base material 101 is preferably the above-mentioned translucent substrate 1.

The organic EL element preferably used in the present invention has an anode and a cathode, and one or more organic functional layers sandwiched between these electrodes on a substrate.

(substrate)
The substrate that can be used for the organic EL element (hereinafter, also referred to as a substrate, a support substrate, a substrate, a support, etc.) is not particularly limited, and a glass substrate, a plastic substrate, or the like can be used, and the substrate is transparent. It may be present or opaque. When light is taken out from the substrate side, the substrate is preferably transparent. Examples of the transparent substrate preferably used include glass, quartz, and a transparent plastic substrate.

Further, as the substrate, to prevent oxygen and water from entering from the substrate side, in test according to JIS Z-0208, the thickness of the water vapor transmission rate at 1μm or ^{1g / (m 2 · 24h)} ( It is preferably 25 ° C. or lower.

Specific examples of the glass substrate include non-alkali glass, low-alkali glass, soda lime glass and the like. Non-alkali glass is preferable from the viewpoint of less adsorption of water, but any of these may be used as long as it is sufficiently dried.

Plastic substrates have been attracting attention in recent years because of their high flexibility, light weight, and resistance to cracking, and their ability to further reduce the thickness of organic EL elements.

The resin film used as the base material of the plastic substrate is not particularly limited, and for example, polyester such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, and cellulose triacetate (TAC). ), Cellulose acetate butyrate, Cellulose acetate propionate (CAP), Cellulose acetate phthalate, Cellulose acetate such as cellulose nitrate or derivatives thereof, Polyvinylidene chloride, Polyvinyl alcohol, Polyethylene vinyl alcohol, Syndiotactic polystyrene, Polycarbonate , Norbornen resin, polymethylpentene, polyether ketone, polyimide, polyether sulfone (PES), polyphenylene sulfide, polysulfones, polyetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethylmethacrylate, acrylic or poly Examples thereof include allylates and organic-inorganic hybrid resins.

Examples of the organic-inorganic hybrid resin include those obtained by combining an organic resin with an inorganic polymer (for example, silica, alumina, titania, zirconia, etc.) obtained by a sol-gel reaction. Of these, norbornene (or cycloolefin-based) resins such as Arton (manufactured by JSR Corporation) or Appel (manufactured by Mitsui Chemicals, Inc.) are particularly preferable.

The plastic substrate usually produced has a relatively high moisture permeability, and may contain moisture inside the substrate. Therefore, when such a plastic substrate is used, a barrier film (also referred to as "gas barrier film" or "water vapor sealing film") that suppresses the intrusion of water vapor, oxygen, etc. is provided on the resin film to provide a gas barrier. A film is preferable.

The material constituting the barrier film is not particularly limited, and an inorganic substance, an organic film, or a hybrid of both of them is used. A film may be formed, and the water vapor permeability (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) measured by a method conforming to JIS K 7129-1992 is 0.01 g / (. preferably m ² · 24h) or less of the barrier film, and further, the measured oxygen permeability by the method based on JIS K 7126-1987 ^{is, 1 × 10 -3 mL / (} m 2 · 24h · atm) or less, the water vapor permeability is preferably ^{1 × 10 -5 g / (m} 2 · 24h) or less of the high barrier film.

The material constituting the barrier film is not particularly limited as long as it is a material that causes deterioration of the element such as moisture and oxygen but has a function of suppressing infiltration, and is, for example, a metal oxide, a metal oxynitride, a metal nitride, or the like. Inorganic substances, organic substances, or hybrid materials of both can be used.

Examples of the metal oxide, metal oxynitride or metal nitride include metal oxides such as silicon oxide, titanium oxide, indium oxide, tin oxide, indium tin oxide (ITO) and aluminum oxide, and metal nitride such as silicon nitride. Examples thereof include metal oxynitrides such as silicon oxynitride and titanium oxynitride.

Further, in order to improve the brittleness of the film, it is more preferable to have a laminated structure of these inorganic layers and layers made of an organic material. The stacking order of the inorganic layer and the organic layer is not particularly limited, but it is preferable to stack the inorganic layer and the organic layer alternately a plurality of times.

The method of providing the barrier film on the resin film is not particularly limited, and any method may be used. For example, a vacuum vapor deposition method, a sputtering method, a reactive sputtering method, a molecular beam epitaxy method, a cluster ion beam method, or an ion plating method may be used. A method, a plasma polymerization method, an atmospheric pressure plasma polymerization method, a CVD method (for example, a plasma CVD method, a laser CVD method, a thermal CVD method, etc.), a coating method, a sol-gel method, or the like can be used. Of these, the method by plasma CVD treatment at atmospheric pressure or near atmospheric pressure is preferable from the viewpoint that a dense film can be formed.

As the translucent substrate used for the laminated light emitting and receiving element of the present invention, it is preferable to use a substrate having a total light transmittance of 70% or more, more preferably 80% or more, and particularly preferably 90% or more. The total light transmittance can be measured according to JIS K 7375: 2008 "Plastic-How to determine the total light transmittance and the total light reflectance".

Examples of the opaque substrate (light reflective substrate) include a metal plate such as aluminum and stainless steel, a film or opaque resin substrate, and a ceramic substrate.

(anode)
As the anode of the organic EL element, a metal having a large work function (4 eV or more), an electrically conductive compound of a metal, or a mixture thereof as an electrode material is preferably used.

Here, the "metal electrically conductive compound" refers to a compound of a metal and another substance having electrical conductivity, and specifically, for example, a metal oxide, a halide, or the like. Refers to those having electrical conductivity.

Specific examples of such an electrode material include metals such as Ag and Au, and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO ₂ and ZnO. The anode can be produced by forming a thin film made of these electrode substances on the substrate by a known method such as thin film deposition or sputtering.

When Ag is used as the anode, it is preferable to have a base layer using a compound containing a nitrogen atom (N) or a sulfur atom (S) in the lower layer in that aggregation of Ag can be suppressed and a thin film can be formed. In particular, it is preferable that the layer contains a Lewis base and is composed of a compound having a Lewis base, that is, a compound containing an atom having an unshared electron pair. Examples of the compound having such a Lewis base include a nitrogen-containing compound and a sulfur-containing compound.

The anode may form a pattern of a desired shape by a photolithography method, and if pattern accuracy is not required so much, the pattern is formed through a mask of a desired shape during vapor deposition or sputtering of the electrode material. You may.

When the light emission is taken out from the anode, it is preferable to increase the light transmittance in the visible light region to more than 50%. The light transmittance can be obtained by measuring the sample with a spectrophotometer V-570 manufactured by JASCO Corporation at a light wavelength of 550 nm. The sheet resistance as an anode is several hundred Ω / sq. The following is preferable. Further, the film thickness of the anode depends on the constituent material, but is usually selected in the range of 10 nm to 1 μm, preferably 10 to 200 nm.

(Organic functional layer)
The organic functional layer (also referred to as "organic EL layer" or "organic compound layer"; the organic functional layer itself may be referred to as "light emitting element") includes at least a light emitting layer, but the light emitting layer is broadly defined. Refers to a layer that emits light when a current is passed through an electrode consisting of a cathode and an anode. Specifically, contains an organic compound that emits light when a current is passed through an electrode consisting of a cathode and an anode. Refers to the layer to be used.

The organic EL element used in the present invention may have a hole injection layer, an electron injection layer, a hole transport layer and an electron transport layer in addition to the light emitting layer, if necessary, and these layers are cathodes. It has a structure sandwiched between the electron and the anode.

In particular,
(I) Anode / light emitting layer / cathode (ii) anode / hole injection layer / light emitting layer / cathode (iii) anode / light emitting layer / electron injection layer / cathode (iv) anode / hole injection layer / light emitting layer / electron Injection layer / cathode (v) anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode (vi) anode / hole transport layer / light emitting layer / electron transport layer / cathode, etc. The structure of.

Further, a cathode buffer layer (for example, lithium fluoride) may be inserted between the electron injection layer and the cathode, and an anode buffer layer (for example, copper phthalocyanine or the like) may be inserted between the anode and the hole injection layer. ) May be inserted.

(Light emitting layer)
The light emitting layer is a layer in which electrons and holes injected from an electrode or an electron transporting layer and a hole transporting layer are recombined to emit light, and the light emitting portion is a light emitting layer even in the light emitting layer. It may be an interface with an adjacent layer. The light emitting layer may be a layer having a single composition, or may have a laminated structure composed of a plurality of layers having the same or different compositions.

The light emitting layer itself may be provided with functions such as a hole injection layer, an electron injection layer, a hole transport layer, and an electron transport layer. That is, (1) an injection function capable of injecting holes through an anode or a hole injection layer and electrons being injected from a cathode or an electron injection layer when an electric field is applied to the light emitting layer, (2) injection. At least one of the transport function of moving charges (electrons and holes) by the force of an electric field, and (3) the light emitting function of providing a field of recombination of electrons and holes inside the light emitting layer and connecting this to light emission. A function may be added. The light emitting layer may have a difference in the ease of injecting holes and the ease of injecting electrons, and may have a large or small transport function represented by the mobility of holes and electrons. , At least one having a function of transferring an electric charge is preferable.

The type of light emitting material used for this light emitting layer is not particularly limited, and conventionally known light emitting materials for organic EL devices can be used. Such luminescent materials are predominantly organic compounds, depending on the desired color tone, for example, Macromol. Symp. Examples thereof include the compounds described in Vol. 125, pp. 17-26. Further, the light emitting material may be a polymer material such as p-polyphenylene vinylene or polyfluorene, and further, a polymer material in which the light emitting material is introduced into a side chain or a polymer material in which the light emitting material is the main chain of the polymer is used. You may use it. As described above, since the light emitting material may have a hole injection function and an electron injection function in addition to the light emitting performance, most of the hole injection materials and electron injection materials described later can also be used as the light emitting material. Can be used.

In the layer constituting the organic EL element, when the layer is composed of two or more kinds of organic compounds, the main component is called a host, the other components are called dopants, and when the host and the dopant are used together in the light emitting layer, the main component. The mixing ratio of the dopant of the light emitting layer (hereinafter, also referred to as the light emitting dopant) to the host compound is preferably 0.1 to 30% by mass by mass.

Dopants used in the light emitting layer are roughly classified into two types: a fluorescent dopant that emits fluorescence and a phosphorescent dopant that emits phosphorescence.

Typical examples of fluorescent dopants are coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, pyrylium dyes, and perylene dyes. , Fluorescein-based dyes, polythiophene-based dyes, rare earth complex-based phosphors, and other known fluorescent compounds.

In the present invention, it is preferable that at least one light emitting layer contains a phosphorescent compound.

In the present invention, the phosphorescent compound is a compound in which light emission from the excited triplet is observed, and the phosphorescence quantum yield is 0.001 or more at 25 ° C.

The phosphorus photon yield is preferably 0.01 or more, more preferably 0.1 or more. The phosphorus photon yield can be measured by the method described on page 398 (1992 edition, Maruzen) of Spectroscopy II of the 4th edition Experimental Chemistry Course 7. The phosphorescent quantum yield in a solution can be measured using various solvents, but the phosphorescent compound used in the present invention may achieve the above phosphorescent quantum yield in any of any solvents.

The phosphorescent dopant is a phosphorescent compound, and as a typical example thereof, it is preferably a complex compound containing a metal of Group 8 to 10 in the periodic table of elements, and more preferably an iridium compound or an osmium compound. , A rhodium compound, a palladium compound, or a platinum compound (platinum complex type compound), preferably an iridium compound, a rhodium compound, or a platinum compound, and most preferably an iridium compound.

Examples of dopants are the compounds described in the following documents or patent publications. J. Am. Chem. Soc. Vol. 123, pp. 4304 to 4312, International Publication No. 2000/70655, No. 2001/93642, No. 2002/02714, No. 2002/15645, No. 2002/44189, No. 2002/081488, Japanese Patent Application Laid-Open No. 2002-280178 No. 2001-181616, 2002-280179, 2001-181617, 2002-280180, 2001-247859, 2002-299060, 2001-313178. Publication, Publication No. 2002-302671, Publication No. 2001-345183, No. 2002-324679, No. 2002-332291, No. 2002-50484, No. 2002-332292, No. 2002-83648. , Japanese Patent Application Laid-Open No. 2002-540572, Japanese Patent Application Laid-Open No. 2002-117978, Japanese Patent Application Laid-Open No. 2002-338588, Japanese Patent Application Laid-Open No. 2002-170684, Japanese Patent Application Laid-Open No. 2002-352960, Japanese Patent Application Laid-Open No. 2002-50483, Publication No. 2002-173674, No. 2002-359082, No. 2002-175884, No. 2002-363552, No. 2002-184582, No. 2003-7469, No. 2002-525808. Japanese Patent Application Laid-Open No. 2003-7471, Japanese Patent Application Laid-Open No. 2002-525833, JP-A-2003-31366, JP-A-2002-226495, JP-A-2002-234894, JP-A-2002-23507, JP-A-2002 No. 241751, No. 2001-319779, No. 2001-319780, No. 2002-62824, No. 2002-100474, No. 2002-203679, No. 2002-343572, No. 2002-203678. Issue, etc.

Only one type of light emitting dopant may be used, or a plurality of types may be used, and by simultaneously extracting light emitted from these dopants, a light emitting element having a plurality of maximum light emission wavelengths can be configured. Further, for example, both a phosphorescent dopant and a fluorescent dopant may be added. When a plurality of light emitting layers are laminated to form an organic EL element, the light emitting dopants contained in each layer may be the same or different, or may be of a single type or a plurality of types. ..

Further, a polymer material in which the light emitting dopant is introduced into a polymer chain or the light emitting dopant is used as a main chain of a polymer may be used.

Examples of the host compound include those having a basic skeleton such as a carbazole derivative, a triarylamine derivative, an aromatic borane derivative, a nitrogen-containing heterocyclic compound, a thiophene derivative, a furan derivative, and an oligoarylene compound, which will be described later. Transport materials and hole transport materials are also examples of suitable examples.

As the light emitting host, a compound having hole transporting ability and electron transporting ability, preventing the wavelength of light emission from being lengthened, and having a high Tg (glass transition temperature) is preferable.

As a specific example of the light emitting host, for example, the compounds described in the following documents are suitable.

JP 2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357977, 2002-334786, 2002-8860, 2002-334787A, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002-75645, 2002-338579, 2002. 2002-105445, 2002-343568, 2002-141173, 2002-352957, 2002-203683, 2002-363227, 2002-231453, 2003 No. 3165, No. 2002-234888, No. 2003-27048, No. 2002-255934, No. 2002-260861, No. 2002-280183, No. 2002-299060, No. 2002- No. 302516, No. 2002-305083, No. 2002-305084, No. 2002-308837, etc.

The luminescent dopant may be dispersed throughout the layer containing the host compound, or may be partially dispersed. A compound having yet another function may be added to the light emitting layer.

A light emitting layer is formed by thinning a film using the above materials by a known method such as a vapor deposition method, a spin coating method, a casting method, an LB method (Langmuir projection method), an inkjet printing method, or a printing method. However, the formed light emitting layer is particularly preferably a molecular deposition film.

Here, the molecular deposition film is a thin film deposited and formed from the vapor phase state of the compound, and a film solidified and formed from the molten state or the liquid phase state of the compound. Usually, this molecular deposition film and the thin film (molecular cumulative film) formed by the LB method can be distinguished by the difference in the aggregated structure and the higher-order structure and the functional difference caused by the difference.

(Hole injection layer and hole transport layer)
The hole injection material used for the hole injection layer has either hole injection or electron barrier property. Further, the hole transport material used for the hole transport layer has an electron barrier property and also has a function of transporting holes to the light emitting layer. Therefore, in the present invention, the hole transport layer is included in the hole injection layer.

The hole injection material and the hole transport material may be either an organic substance or an inorganic substance. Specifically, for example, triazole derivative, oxadiazole derivative, imidazole derivative, polyarylalkane derivative, pyrazoline derivative, pyrazolone derivative, phenylenediamine derivative, arylamine derivative, amino-substituted calcon derivative, oxazole derivative, styrylanthracene derivative, fluorenone derivative. , Hydrazone derivatives, stylben derivatives, silazane derivatives, aniline-based copolymers, porphyrin compounds, thiophene oligomers and other conductive polymer oligomers. Of these, arylamine derivatives and porphyrin compounds are preferred.

Among the arylamine derivatives, aromatic tertiary amine compounds and styrylamine compounds are preferable, and aromatic tertiary amine compounds are more preferable.

Typical examples of the above aromatic tertiary amine compound and styrylamine compound are N, N, N', N'-tetraphenyl-4,4'-diaminophenyl; N, N'-diphenyl-N, N'. -Bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine (TPD); 2,2-bis (4-di-p-tolylaminophenyl) propane; 1,1- Bis (4-di-p-tolylaminophenyl) cyclohexane; N, N, N', N'-tetra-p-tolyl-4,4'-diaminobiphenyl; 1,1-bis (4-di-p-) Trillaminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, N ′ -Di (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) biphenyl N, N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4'-[4- (di-p-tolylamino) styryl] stillben; 4-N, N-diphenylamino -(2-Diphenylvinyl) benzene; 3-methoxy-4'-N, N-diphenylaminostylben; N-phenylcarbazole, as well as the two condensed aromatics described in US Pat. No. 5,061569. Those having a ring in the molecule, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (α-NPD), triphenyl described in JP-A-4-308688. Examples thereof include 4,4', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine (MTDATA) in which three amine units are linked in a starburst type. Inorganic compounds such as type-Si and p-SiC can also be used as the hole injection material.

Further, in the present invention, the hole transport material of the hole transport layer preferably has a fluorescence maximum wavelength of 415 nm or less. That is, the hole transporting material is preferably a compound having a hole transporting ability, preventing the wavelength of light emission from being lengthened, and having a high Tg.

As the hole injection layer and the hole transport layer, the hole injection material and the hole transport material are known, for example, vacuum deposition method, spin coating method, casting method, LB method, inkjet method, printing method, printing method and the like. It can be formed by thinning the film according to the above method.

In the present invention, it is preferable to use the hole injection material and the hole transport material as the organic material for the electronic device of the present invention. Then, the hole injection material, the hole transport material, the organic solvent, and the solution containing the cellulose nanofibers (composition for manufacturing an electronic device) are subjected to a spin coating method, a casting method, an inkjet method, a spray method, a printing method, and the like. It is preferably formed by coating by a slot type coater method or the like. Above all, the inkjet printing method is preferable from the viewpoint that a homogeneous film can be easily obtained and pinholes are less likely to be formed.

The thickness of the hole injection layer and the hole transport layer is not particularly limited, but is usually about 5 nm to 5 μm. The hole injection layer and the hole transport layer may have a one-layer structure composed of one or more of the above materials, respectively, and may have a laminated structure composed of a plurality of layers having the same composition or a different composition. May be good. When both the hole injection layer and the hole transport layer are provided, different materials are usually used among the above materials, but the same material may be used.

(Electronic injection layer and electron transport layer)
The electron injection layer may have a function of transferring electrons injected from the cathode to the light emitting layer, and as the material thereof, any conventionally known compound can be selected and used.

Examples of the material used for this electron-injected layer (hereinafter, also referred to as electron-injected material) include heterocyclic tetracarboxylic acid anhydrides such as nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyrandioxide derivatives, and naphthalene perylene, and carbodiimides. , Freolenilidene methane derivative, anthraquinodimethane and antron derivative, oxadiazole derivative and the like.

Further, a series of electron transporting compounds described in JP-A-59-194393 are disclosed as materials for forming a light emitting layer in the publication, but as a result of examination by the present inventors, electron injection It was found that it could be used as a material. Further, among the above oxadiazole derivatives, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is replaced with a sulfur atom, and a quinoxalin derivative having a quinoxalin ring known as an electron-withdrawing group can also be used as an electron injection material.

Further, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (abbreviated as Alq ₃ ), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-). Kinolinol) aluminum, tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), etc., and the central metal of these metal complexes are In. , Mg, Cu, Ca, Sn, Ga or Pb replaced with a metal complex can also be used as the electron injection material.

In addition, metal-free or metal phthalocyanine, or those whose terminals are substituted with an alkyl group, a sulfonic acid group, or the like can also be preferably used as the electron injection material. Further, similarly to the hole injection layer, inorganic semiconductors such as n-type-Si and n-type-SiC can also be used as the electron injection material.

The preferred compound used in the electron transport layer preferably has a fluorescence maximum wavelength of 415 nm or less. That is, the compound used for the electron transport layer is preferably a compound having an electron transport ability, preventing the wavelength of light emission from being lengthened, and having a high Tg.

The electron injection layer is formed by thinning the electron injection material by a known method such as a vacuum deposition method, a spin coating method, a casting method, an LB method, an inkjet method, a printing method, or a printing method. Can be done.

In the present invention, it is preferable to use the electron-injected material as the organic material for the electronic device of the present invention. Then, the solution containing the electron injection material, the organic solvent, and the cellulose nanofibers (composition for manufacturing an electronic device) is subjected to a spin coating method, a casting method, an inkjet method, a spray method, a printing method, a slot type coater method, or the like. It is preferably formed by coating. Above all, the inkjet method is preferable from the viewpoint that a homogeneous film can be easily obtained and pinholes are less likely to be formed.

The thickness of the electron injection layer is not particularly limited, but is usually selected in the range of 5 nm to 5 μm. The electron injecting layer may have a one-layer structure composed of one or more of these electron injecting materials, or may have a laminated structure composed of a plurality of layers having the same composition or a different composition.

In the present specification, among the electron injection layers, when the ionization energy is larger than that of the light emitting layer, the layer is referred to as an electron transport layer. Therefore, in the present specification, the electron transport layer is included in the electron injection layer.

The electron transport layer is also referred to as a hole blocking layer (hole block layer), and is, for example, International Publication No. 2000/70655, JP-A-2001-313178, JP-A-11-204258, and JP-A-11-204359. , And those described on page 237 of "Organic EL Element and Its Industrialization Frontline (Published by NTS Co., Ltd. on November 30, 1998)". In particular, in a so-called "phosphorescent light emitting device" that uses an orthometal complex-based dopant for the light emitting layer, it is preferable to adopt a configuration having an electron transport layer (hole blocking layer) as described in (v) and (vi) above.

(Buffer layer)
A buffer layer (electrode interface layer) may be present between the anode and the light emitting layer or the hole injection layer, and between the cathode and the light emitting layer or the electron injection layer.

The buffer layer is a layer provided between the electrode and the organic layer in order to reduce the driving voltage and improve the light emission efficiency. "Organic EL element and its forefront of industrialization (published by NTS on November 30, 1998)" ) ”, Volume 2, Chapter 2,“ Electrode Materials ”(pages 123 to 166), and includes an anode buffer layer and a cathode buffer layer.

The details of the anode buffer layer are also described in JP-A-9-45479, 9-2660062, 8-288609, etc., and as a specific example, a phthalocyanine buffer layer typified by copper phthalocyanine. , Oxide buffer layer typified by vanadium oxide, amorphous carbon buffer layer, polymer buffer layer using conductive polymer such as polyaniline (emeraldine) and polythiophene, and the like.

The details of the cathode buffer layer are also described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, etc., and specifically, a metal typified by strontium, aluminum, or the like. Examples thereof include a buffer layer, an alkali metal compound buffer layer typified by lithium fluoride, an alkaline earth metal compound buffer layer typified by magnesium fluoride, and an oxide buffer layer typified by aluminum oxide.

The buffer layer is preferably a very thin film, and although it depends on the material, the thickness thereof is preferably in the range of 0.1 to 100 nm. Further, in addition to the above basic constituent layers, layers having other functions may be appropriately laminated, if necessary.

(cathode)
As the cathode of the organic EL element, a metal having a small work function (less than 4 eV) (hereinafter referred to as an electron-injectable metal), an alloy, an electrically conductive compound of the metal, or a mixture thereof is used as an electrode material. ..

Specific examples of such electrode materials include sodium, magnesium, lithium, aluminum, indium, rare earth metals, sodium-potassium alloy, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum. / Aluminum oxide (Al ₂ O ₃ ) mixture, lithium / aluminum mixture and the like.

When the cathode is light-reflecting, the light reflectance is preferably 80% or more in the visible light region. The light reflectance can be obtained by measuring the sample with a spectroscopic light measuring machine USPM-RUIII manufactured by Olympus Corporation at a light wavelength of 550 nm.

The cathode can be produced by forming a thin film of the electrode material on the organic compound layer (organic EL layer) by a method such as vapor deposition or sputtering.

The sheet resistance as a cathode is several hundred Ω / sq. The following is preferable, and the film thickness is usually selected in the range of 10 nm to 1 μm, preferably 50 to 200 nm. It is preferable to make either the anode or the cathode of the organic EL element transparent or translucent in order to transmit the emitted light because the luminous efficiency is improved.

[Manufacturing method of organic EL element]
As an example of a method for manufacturing an organic EL device, a method for manufacturing an organic EL device including an anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode will be described.

First, a thin film made of a desired electrode substance, for example, an anode substance is formed on a suitable substrate so as to have a thickness of 1 μm or less, preferably 10 to 200 nm, and an anode is formed by a method such as thin film deposition or sputtering. To make. Next, an organic compound thin film (organic thin film) of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and a hole blocking layer, which are element materials, is formed on this.

As a method for thinning these organic thin films, as described above, there are a spin coating method, a casting method, an inkjet printing method, a spray method, a vapor deposition method, a printing method, a slot coating method and the like, and a homogeneous film can be obtained. The inkjet printing method is preferable because it is easy to generate and pinholes are not easily formed, and in the present invention, the composition for producing an electronic device of the present invention can be used.

Moreover, you may apply a different film forming method for each layer. The case of employing an evaporation method in the deposition, the deposition conditions may vary due to kinds of materials used, generally boat temperature 50 to 450 ° C., vacuum of ¹⁰ -6 ^{to 10} -2 Pa, the deposition rate 0.01 It is desirable to appropriately select in the range of ~ 50 nm / sec, substrate temperature -50 to 300 ° C., and thickness 0.1 nm to 5 μm.

After forming these layers, a thin film made of a material for a cathode is formed on the layer so as to have a thickness of 1 μm or less, preferably in the range of 50 to 200 nm, and a cathode is provided by a method such as vapor deposition or sputtering. Therefore, a desired organic EL element can be obtained. The organic EL element is preferably manufactured from the hole injection layer to the cathode by one vacuuming, but it may be taken out in the middle and a different film forming method may be applied. At that time, consideration must be given to performing the work in a dry inert gas atmosphere.

[Encapsulation of organic EL element]
The sealing means for the organic EL element is not particularly limited, but for example, after sealing the outer peripheral portion of the organic EL element with a sealing adhesive, the sealing member is formed so as to cover the light emitting region of the organic EL element. There is a method of arranging.

Examples of the sealing adhesive include acrylic acid-based oligomers, photocurable and thermosetting adhesives having a reactive vinyl group of methacrylic acid-based oligomers, and moisture-curable adhesives such as 2-cyanoacrylic acid ester. Can be mentioned. In addition, heat and chemical curing type (two-component mixture) such as epoxy type can be mentioned. Further, hot melt type polyamide, polyester and polyolefin can be mentioned. In addition, a cation-curable type ultraviolet-curable epoxy resin adhesive can be mentioned.

As the sealing member, in addition to the glass plate, a polymer film and a metal film can be preferably used from the viewpoint of thinning the organic EL element. In the case of a polymer film, it is preferable to impart the above-mentioned gas barrier property.

The sealing structure includes a structure in which the space between the organic EL element and the sealing member is hollow, and a filling and sealing structure in which a sealing material such as an adhesive is filled between the organic EL element and the sealing member. Can be mentioned.

In the gap between the sealing member and the light emitting region of the organic EL element, in addition to the sealing adhesive, in the gas phase and liquid phase, an inert gas such as nitrogen or argon, fluorine hydrocarbon, silicone oil, etc. It is also possible to inject a non-active liquid. Further, the gap between the sealing member and the display region of the organic EL element can be evacuated, an inert gas can be sealed in the gap, or a desiccant can be arranged.

If the above organic EL element is provided with a shadow mask only when the light emitting layer is formed and the other layers are shared, patterning of the shadow mask or the like is unnecessary, and the deposition method, casting method, spin coating method, inkjet method, printing can be performed on one surface. A film can be formed by a method or the like.

When patterning only the light emitting layer, the method is not limited, but a vapor deposition method, an inkjet printing method, or a printing method is preferable. When the vapor deposition method is used, patterning using a shadow mask is preferable.

It is also possible to reverse the production order and produce the cathode, the electron injection layer, the electron transport layer, the light emitting layer, the hole transport layer, the hole injection layer, and the anode in this order.

When a DC voltage is applied to the display device thus obtained, light emission can be observed by applying a voltage of about 2 to 40 V with the positive polarity of the anode and the negative polarity of the cathode. Further, even if a voltage is applied with the opposite polarity, no current flows and no light emission occurs. Further, when an AC voltage is applied, light is emitted only when the anode is in the + state and the cathode is in the-state. The waveform of the applied alternating current may be arbitrary.

As the light emitting device according to the present invention, it is preferable to select a light emitting material that emits green light or red light from the above-mentioned light emitting dopants from the viewpoint of using the light emitting element for a pulse oximeter.

Hereinafter, as an example of the light emitting dopant, an example of each light emitting material of the green light emitting material (GD-1) and the red light emitting material (RD-1) will be given.

FIG. 6 is a cross-sectional view showing an example of a multicolor laminated light emitting and receiving element.

The laminated light emitting / receiving element 50-1 shown in FIG. 6A is an example in which green and red light emitting organic EL elements are individually arranged on the same substrate.
From the lower layer, the translucent substrate 1, the first electrode 2, the red light emitting element 3-1 and the green light emitting element 3-2, the intermediate insulating layer 11, the light transmissive third electrode 6, and the light receiving element separated from each other on the same substrate. 5. It is composed of a light-reflecting electrode 7, an adhesive layer 8 and a sealing material 9. However, the light receiving layer 5 of the laminated light emitting and receiving element 50-1 may be one light receiving element that covers the two light emitting layers.

The laminated light emitting / receiving element 50-2 shown in FIG. 6B is an example in which green and red light emitting organic EL elements are laminated.
From the lower layer, the translucent substrate 1, the first electrode 2, the red light emitting element 3-1 and the light transmissive intermediate electrode 2-2, the green light emitting element 3-2, the intermediate insulating layer 11, and the light transmissive third electrode 6 It is composed of a light receiving element 5, a light reflecting electrode 7, an adhesive layer 8 and a sealing material 9.

[3] Intermediate Insulation Layer The intermediate insulation layer according to the present invention contains an organic compound having both a covalent bond site capable of covalently bonding with silver and a coordinate bond site capable of coordinating bond with silver in the molecule. It is preferable that the layer is composed of

Examples of the method for forming such an intermediate layer insulating layer include a method using a wet process such as a coating method, an inkjet method, a coating method, and a dip method, a vapor deposition method (resistive heating, EB method (electron beam method), etc.), and sputtering. Examples include a method using a dry process such as a method and a CVD method. Of these, the vapor deposition method is preferably applied.

Further, the thickness of the intermediate insulating layer is preferably in the range of 1 to 100 nm, more preferably in the range of 5 to 30 nm. Within this range, the effect can be obtained regardless of the thickness.

The intermediate insulating layer contains an organic compound having both the covalent bond site and the coordination bond site in the molecule. It is preferable that the coordination bond site is a nitrogen atom contained in an aromatic heterocycle and is not involved in aromaticity.

The "nitrogen atom having an unshared electron pair that does not participate in aromaticity" is a nitrogen atom having an unshared electron pair (also referred to as "lone electron pair"), and has aromaticity of an unsaturated cyclic compound. In addition, it refers to a nitrogen atom in which the unshared electron pair is not directly involved as an essential element. That is, the unshared electron pair is not involved in the delocalized π-electron system on the conjugated unsaturated ring structure (aromatic ring) as essential for the expression of aromaticity in terms of the chemical structural formula. Refers to a nitrogen atom.

A detailed description of the compound can be referred to in Japanese Patent No. 6241193.

[4] Light-receiving element As the light-receiving element of the stacked light-emitting light-receiving element of the present invention, it is preferable to use a planar organic thin-film solar cell (OPV) or an organic photodetector (OPD). Here, an example of using an organic thin film solar cell (OPV) as a light receiving element according to the present invention will be described.

FIG. 7 is a cross-sectional view showing an example of a solar cell having a single configuration (a configuration in which the bulk heterojunction layer is one layer) composed of a bulk heterojunction type organic photoelectric conversion element.

In FIG. 7, the bulk heterojunction type organic photoelectric conversion element 200 has an anode 202 which is a transparent electrode, a hole transport layer 207, a photoelectric conversion layer 204 of the bulk heterojunction layer, and an electron transport layer 208 (on one surface of the substrate 201). Alternatively, it is also referred to as a buffer layer) and the cathode 203 are sequentially laminated.

(substrate)
The substrate 201 is a member that holds the anode 202, the photoelectric conversion layer 204, and the cathode 203 that are sequentially laminated. In the present embodiment, since the light to be photoelectrically converted is incident from the substrate 201 side, the substrate 201 is preferably a member transparent to the wavelength of the light to be photoelectrically converted. As the substrate 201, for example, a glass substrate, a resin substrate, or the like is used. The substrate 201 is not indispensable, and the configuration is a basic configuration. In the case of the laminated light emitting and receiving element of the present invention, the anode 202, the photoelectric conversion layer 204, and the cathode 203 are placed on the intermediate insulating layer. It may be formed.

(Photoelectric conversion layer)
The photoelectric conversion layer 204 is a layer that converts light energy into electrical energy, and is configured to have a bulk heterojunction layer in which a p-type semiconductor material and an n-type semiconductor material are uniformly mixed. The p-type semiconductor material relatively functions as an electron donor (donor), and the n-type semiconductor material relatively functions as an electron acceptor (acceptor). Here, the electron donor and the electron acceptor are described as "an electron donor that, when light is absorbed, electrons move from the electron donor to the electron acceptor to form a hole-electron pair (charge separation state). And electron acceptors, which donate or accept electrons by photoreaction, rather than simply donating or accepting electrons like electrodes.

In FIG. 7, the light incident from the anode 202, which is a transparent electrode, via the substrate 201 is absorbed by the electron acceptor or electron donor in the bulk heterojunction layer of the photoelectric conversion layer 204, and is transferred from the electron donor to the electron acceptor. Electrons move to form a hole-electron pair (charge separation state). The generated charge is due to the internal electric field, for example, the potential difference between the anode 202 and the cathode 203 when the work functions of the anode 202 and the cathode 203 are different, so that electrons pass between electron acceptors and holes pass between electron donors. As it passes, it is carried to different electrodes and the photocurrent is detected. For example, when the work function of the anode 202 is larger than the work function of the cathode 203, electrons are transported to the anode 202 and holes are transported to the cathode 203. If the magnitude of the work function is reversed, electrons and holes are transported in the opposite direction. Further, the transport direction of electrons and holes can be controlled by applying an electric potential between the anode 202 and the cathode 203.

Although not shown in FIG. 7, another layer such as a hole block layer, an electron block layer, an electron injection layer, a hole injection layer, or a smoothing layer may be provided.

Further, for the purpose of further improving the sunlight utilization rate (photoelectric conversion efficiency), a tandem type configuration (a configuration having a plurality of bulk heterojunction layers) in which such photoelectric conversion elements are laminated may be used.

Examples of the p-type semiconductor material include various condensed polycyclic aromatic compounds and conjugated compounds.

Examples of the condensed polycyclic aromatic compound include anthracene, tetracene, pentacene, hexacene, heptanene, chrysene, picene, fluminene, pyrene, peropylene, perylene, terylene, quaterylene, coronene, ovalene, circumanthracene, bisanthene, zeslen, heptazeslen Examples thereof include compounds such as pyranesrene, biolanten, isobiolanten, circobiphenyl and anthracene, and derivatives and precursors thereof.

Examples of the conjugate compound include polythiophene and its oligomer, polypyrrole and its oligomer, polyaniline, polyphenylene and its oligomer, polyphenylene vinylene and its oligomer, polythienylene vinylene and its oligomer, polyacetylene, polydiacetylene, tetrathiafluvalene compound, and quinone. Examples include compounds, cyano compounds such as tetracyanoquinodimethane, fullerene and derivatives or mixtures thereof.

In particular, among polythiophenes and their oligomers, α-sexualiophene α, ω-dihexyl-α-sexualiophene, α, ω-dihexyl-α-kinkethiophene, α, ω-bis (3-), which are thiophene hexamers, Oligomers such as butoxypropyl) -α-sexualiophene can be preferably used.

Other examples of high molecular weight p-type semiconductors include polyacetylene, polyparaphenylene, polypyrrole, polyparaphenylene sulfide, polythiophene, polyphenylene vinylene, polycarbazole, polyisotianaften, polyheptadiyne, polyquinoline, polyaniline, and the like. Substituted-unsubstituted alternating copolymer polythiophenes such as JP-A-2006-36755, JP-A-2007-51289, JP-A-2005-76030, J. Mol. Amer. Chem. Soc. , 2007, p4112, J. Mol. Amer. Chem. Soc. , 2007, p7246 and other polymers with a fused thiophene structure, WO 2008/000664, Adv. Mater. , 2007, p4160, Macromolecules, 2007, Vol. 40, thiophene copolymers such as p1981 and the like can be mentioned.

Further, porphyrin, copper phthalocyanine, tetrathiafulvalene (TTF) -tetracyanoquinodimethane (TCNQ) complex, bisethylenedithiotetrathiafulvalene (BEDTTTF) -perchlorate complex, BEDTTTTF-iodine complex, TCNQ-iodine complex, etc. Organic molecular complexes of C60, C70, C76, C78, C84, etc., carbon nanotubes such as SWNT, dyes such as merocyanine pigments, hemicyanine pigments, etc., and σ-conjugated polymers such as polysilane, polygerman, etc. The organic / inorganic mixed material described in Kai 2000-260999 can also be used.

Among these π-conjugated materials, at least one selected from the group consisting of condensed polycyclic aromatic compounds such as pentacene, fullerenes, condensed ring tetracarboxylic acid diimides, metal phthalocyanine, and metal porphyrin is preferable. Further, pentacene is more preferable.

Examples of pentacene have substituents described in International Publication No. 03/16599, International Publication No. 03/28125, US Pat. No. 6,690,029, JP-A-2004-107216, and the like. Pentacene Derivatives, Pentacene Precasa, J. et al., Described in US Patent Application Publication No. 2003/136964, etc. Amer. Chem. Soc. , Vol127. Examples thereof include the substituted acenes described in No. 14.4986 and the like and derivatives thereof.

Examples of n-type semiconductor materials include fullerene, octaazaporphyrin, perfluoro compounds of p-type semiconductors (perfluoropentacene, perfluorophthalocyanine, etc.), naphthalenetetracarboxylic dianhydride, naphthalenetetracarboxylic dianimide, and perylenetetracarboxylic acid. Examples thereof include aromatic carboxylic dianhydrides such as anhydrides and diimides of perylenetetracarboxylic dians, and high molecular compounds containing imidized products thereof as a skeleton.

Of these, fullerene-containing polymer compounds are preferable. Examples of the fullerene-containing polymer compound include fullerene C60, fullerene C70, fullerene C76, fullerene C78, fullerene C84, fullerene C240, fullerene C540, mixed fullerene, fullerene nanotube, multilayer nanotube, single layer nanotube, nanohorn (conical type) and the like. Examples include high molecular compounds having a skeleton. As the fullerene-containing polymer compound, a polymer compound (derivative) having fullerene C60 as a skeleton is preferable.

Fullerene-containing polymers are roughly classified into polymers in which fullerenes are pendant from the polymer main chain and polymers in which fullerenes are contained in the polymer main chain. Fullerenes are contained in the polymer main chain. The compound is preferable.

This is not because the polymer containing fullerene in the main chain does not have a branched structure, so that it can be packed with high density when solidified, and as a result, high mobility can be obtained. It is presumed to be.

Examples of the method for forming the bulk heterojunction layer in which the electron acceptor and the electron donor are mixed include a thin-film deposition method, a coating method (including a casting method and a spin coating method), and the like.

(cathode)
In the light receiving element according to the present invention, the cathode is preferably an electrode that extracts electrons. For example, when it is used as a cathode, it may be a single layer of a conductive material, but in addition to a material having conductivity, a resin that retains these may be used in combination.

The cathode material is required to have sufficient conductivity, a work function close to the extent that it does not form a Schottky barrier when bonded to the n-type semiconductor material, and does not deteriorate. That is, it is preferable that the metal has a work function 0 to 0.3 eV larger than that of the LUMO of the n-type semiconductor material used for the bulk heterojunction layer, and it is preferable that the work function is 4.0 to 5.1 eV. On the other hand, it is not preferable that the work function is deeper than that of the anode that extracts holes, and a metal having a work function shallower than that of the n-type semiconductor material may cause interlayer resistance. Therefore, the actual value is 4.2 to 4.8 eV. It is preferably a metal having a work function. Therefore, oxide-based materials such as aluminum, gold, silver, copper, indium, or zinc oxide, ITO, and titanium oxide are also preferable. More preferably, it is aluminum, silver, copper, and even more preferably silver.

If necessary, an alloy may be used, and for example, a magnesium / silver mixture, a magnesium / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, a lithium / aluminum mixture, aluminum and the like are preferable. Is. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering. The film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 to 200 nm.

When the cathode side is to be light-transmitting, for example, a conductive material suitable for the cathode such as aluminum and aluminum alloy, silver and silver compound is thinly prepared with a film thickness of about 1 to 20 nm, and then conductive light is applied. By providing a film of a transparent material, it can be used as a light-transmitting cathode.

(anode)
In the present invention, the anode is preferably an electrode for extracting holes. For example, when used as an anode, it is preferably an electrode that transmits light of 380 to 800 nm. As the material, for example, transparent conductive metal oxides such as indium tin oxide (ITO), SnO ₂ , ZnO, metal thin films such as gold, silver and platinum, metal nanowires and carbon nanotubes can be used.

In addition, it is selected from the group consisting of derivatives of polypyrrole, polyaniline, polythiophene, polythienylene vinylene, polyazulene, polyisothianaften, polycarbazole, polyacetylene, polyphenylene, polyphenylene vinylene, polyacetylene, polyphenylacetylene, polydiaacetylene and polynaphthalene. Conductive polymers and the like can also be used. Further, a plurality of these conductive compounds can be combined to form a transparent electrode.

(Hole transport layer and electron block layer)
Since the organic photoelectric conversion element can take out the electric charge generated in the bulk heterojunction layer more efficiently, it has a hole transport layer / electron block layer between the bulk heterojunction layer and the transparent electrode. Is preferable.

As the material constituting these layers, for example, as the hole transport layer, PEDOT such as Heraeus Clevious, polyaniline and its doping material, the cyanide compound described in WO2006 / 019270 and the like can be used.

The hole transport layer having a LUMO level shallower than the LUMO level of the n-type semiconductor material used for the bulk heterojunction layer has a rectifying effect that prevents electrons generated in the bulk heterojunction layer from flowing to the anode side. The electronic block function to have is given. Such a hole transport layer is also called an electron block layer, and it is preferable to use a hole transport layer having such a function. As such a material, a triarylamine-based compound described in JP-A-5-271166 and the like, a metal oxide such as molybdenum oxide, nickel oxide, and tungsten oxide can be used. Further, a layer made of a single p-type semiconductor material used for the bulk heterojunction layer can also be used. The means for forming these layers may be either a vacuum vapor deposition method or a solution coating method, but a solution coating method is preferable. It is preferable to form a coating film on the lower layer before forming the bulk heterojunction layer because it has the effect of leveling the coated surface and reduces the influence of leaks and the like.

(Electron transport layer, hole block layer and buffer layer)
The organic photoelectric conversion element can take out the electric charge generated in the bulk heterojunction layer more efficiently by forming an electron transport layer, a hole block layer, and a buffer layer between the bulk heterojunction layer and the cathode. Therefore, it is preferable to have these layers.

Further, as the electron transport layer, octaazaporphyrin and a perfluoro compound of a p-type semiconductor (perfluoropentacene, perfluorophthalocyanine, etc.) can be used, but similarly, the p-type semiconductor material used for the bulk heterojunction layer can be used. The electron transport layer having a HOMO level deeper than the HOMO level is provided with a hole blocking function having a rectifying effect so that holes generated in the bulk heterojunction layer do not flow to the cathode side. Such an electron transport layer is also called a hole block layer, and it is preferable to use an electron transport layer having such a function. Examples of such materials include phenanthrene compounds such as vasocuproin, n-type semiconductor materials such as naphthalenetetracarboxylic acid anhydride, naphthalenetetracarboxylic acid diimide, perylenetetracarboxylic acid anhydride, and perylenetetracarboxylic acid diimide, and titanium oxide. It is also possible to use an n-type inorganic oxide such as zinc oxide or gallium oxide, a layer made of a single n-type semiconductor material used for the bulk heterojunction layer, or the like.

Further, alkali metal compounds such as lithium fluoride, sodium fluoride and cesium fluoride can be used.

Among these, it is preferable to use an alkali metal compound which is further doped with an organic semiconductor molecule and also has a function of improving electrical bonding with the metal electrode (cathode). In the case of an alkali metal compound layer, it may be a buffer layer in particular.

(Other layers)
For the purpose of improving the energy conversion efficiency and the life of the device, various intermediate layers may be provided in the device. Examples of the intermediate layer include a hole block layer, an electron block layer, a hole injection layer, an electron injection layer, an exciton block layer, a UV absorption layer, a light reflection layer, a wavelength conversion layer and the like.

(Patterning)
The method or process for patterning the electrode, photoelectric conversion layer, hole transport layer, electron transport layer, or the like is not particularly limited, and a known method can be appropriately applied.

If it is a soluble material such as a photoelectric conversion layer or a transport layer, only unnecessary parts may be wiped off after applying the entire surface such as die coat or dip coat, or patterning directly at the time of application using a method such as an inkjet printing method or screen printing. You may.

In the case of an insoluble material such as an electrode material, the electrode can be mask-deposited at the time of vacuum deposition, or patterned by a known method such as etching or lift-off. Further, the pattern may be formed by transferring the pattern formed on another substrate.

(Sealing)
Further, since the produced organic photoelectric conversion element is not deteriorated by oxygen, moisture, etc. in the environment, the organic photoelectric conversion element which is a light receiving element is sealed by the above-mentioned known method in the same manner as the organic EL element which is a light emitting element. Is preferable. For example, a method of sealing by adhering a cap made of aluminum or glass with an adhesive, a plastic film on which a gas barrier layer such as aluminum, silicon oxide, or aluminum oxide is formed and an organic photoelectric conversion element are adhered with an adhesive. Adhesive method, spin-coating method of organic polymer material with high gas barrier property (polyvinyl alcohol, etc.), inorganic thin film (silicon oxide, aluminum oxide, etc.) or organic film (parylene, etc.) with high gas barrier property under vacuum Examples thereof include a method of depositing in and a method of laminating these in a composite manner.

[5] Pulse Oximeter A pulse oximeter can be mentioned as a preferable example of the application of the stacked light emitting and receiving element of the present invention.

The pulse oximeter uses the principle that HbO ₂ (hemoglobin containing oxygen) and Hb (hemoglobin containing no oxygen) in blood hemoglobin have different light absorption characteristics depending on the wavelength of light, and irradiates the inside of the living body. A device that non-invasively measures blood oxygen saturation SpO ₂ by detecting the emitted light as transmitted light or reflected light.

As a conventional pulse oximeter, a transmission type pulse oximeter described in JP-A-9-173322 is known, but in order to improve the detection sensitivity, light transmitted through the living body is efficiently collected. In addition to the need to detect and increase the signal strength, it has been required not to impair the usability because it is directly attached to the living body (mainly the finger). The laminated light emitting / receiving element of the present invention is characterized by being a reflective type, and therefore does not need to be attached to a fingertip or the like, and in addition to designing a thin and compact optical system for light collection / detection. Since the light detection efficiency is high, it can be expected to improve versatility and practicality, such as a form in which a pulse oximeter is wrapped around a wrist or arm for measurement.

FIG. 8 is a perspective view of a reflective pulse oximeter that can be wrapped around a wrist and includes the laminated light emitting / receiving element of the present invention.

The reflective pulse oximeter 60, which is provided with the laminated light emitting / receiving element of the present invention and can be wrapped around the wrist, has the laminated light emitting / receiving element 62 formed on the substrate 61 arranged inside the band 63 and on the opposite side. It is composed of a magic tape (registered trademark) 64 that can be attached to and detached from the subject.

A constant amount of light is constantly output from the light emitting element 62 to irradiate the inside of the living body, and the amount of reflected light changes depending on the amount of hemoglobin combined with oxygen flowing in the blood. Since the light receiving element 62 outputs a signal depending on the amount of received light of the reflected light, the oxygen concentration in the blood of the subject can be measured by a measurement analysis device connected by a take-out wiring (not shown).

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In the examples, the indication of "parts" or "%" is used, but unless otherwise specified, it indicates "parts by mass" or "% by mass".

[Example 1]
<Manufacturing of adjacently arranged light emitting and receiving elements 101 on the same surface>
A light emitting element 101, which is an organic EL element having a circular structure as shown in FIG. 1, was produced according to the following method. The area of the light emitting element 101 was adjusted to a circular shape having a radius of 1.5 mm and an area of 0.07 cm ² .

(Formation of the first electrode)
ITO (In ₂ O ₃ : SnO ₂ = 90:10 (mass% ratio)) is formed on a transparent glass substrate (30 mm × 30 mm) by a sputtering method under the condition that the thickness is 150 nm, and then patterning is performed. To form a first electrode (anode) composed of an ITO layer. Next, the substrate was set in the CVD apparatus, and an insulating layer of SiO ₂ was formed on the entire surface by a conventional method with a film thickness of 200 nm. Next, a photoresist was applied and UV irradiation was performed through a SiO ₂ insulating layer patterning mask. Then developed by a developing solution, ITO expose the SiO ₂ insulating film of the area desired to be exposed and then peeled off the SiO ₂ insulating film area to expose the ITO by plasma etching under CF ₄ atmosphere. Next, the photoresist on the remaining SiO ₂ insulating film was dissolved with an organic solvent and removed, and then a glass substrate in which the ITO conductive layer and the SiO ₂ insulating layer were each patterned was produced. This was ultrasonically washed with isopropyl alcohol, dried with dry nitrogen gas, and UV ozone washed for 5 minutes.

(Formation of take-out electrode)
After forming MAM (Mo molybdenum / Al aluminum / Mo molybdenum) with a thickness of 150 nm as the first extraction electrode portion and connecting it to the first electrode of the manufactured element and the extraction portion of the second electrode described later. As the second take-out electrode portion, MAM (Mo molybdenum / Al aluminum / Mo molybdenum) was formed and connected so that the cross-sectional shape was trapezoidal.

(Formation of organic functional layer for light emitting element)
An organic functional layer including a light emitting layer was prepared on the first electrode of the prepared glass substrate according to the procedure shown below. The glass substrate was dried in a glove box having a dew point of −80 ° C. or lower and an oxygen concentration of 1 ppm or less, and then transferred from the glove box into a vacuum vapor deposition apparatus forming an organic functional layer without being exposed to the atmosphere.

Each of the vapor deposition crucibles in the vacuum vapor deposition apparatus was filled with the constituent materials of each layer in the optimum amount for manufacturing the device. As the crucible for vapor deposition, a crucible made of molybdenum or tungsten made of a resistance heating material was used.

Subsequently, the chamber of the vacuum vapor deposition apparatus was depressurized to a degree of vacuum of 1 × 10 ^-4 Pa, and the compound M-1 (MTDATA) represented by the following chemical formula was deposited using a pattern mask for forming a light emitting area at a vapor deposition rate of 0. A hole injection layer (HIL) having a layer thickness of 15 nm was formed by vapor deposition on the first electrode at 1 nm / sec.

Next, the compound M-2 (α-NPD) represented by the following chemical formula was deposited on the hole injection layer to form a hole transport layer (HTL) having a layer thickness of 30 nm.

On this, as an electron blocking layer (EBL), N, N'-bis- (1-naphthyl) -N, N'-diphenyl-1,1'-biphenyl-4,4'-diamine (NPB) was added at 5 nm. It was deposited to the thickness of.

Next, the heating boat containing the compound H-2 represented by the following chemical formula and the heating boat containing the compound RD-1 (red light emitting) represented by the following chemical formula are independently energized and used as a light emitting host. The vapor deposition rate of a certain H-2 and the light emitting dopant RD-1 was adjusted to be 100: 6, and a phosphorescent light emitting layer (EML) having a film thickness of 20 nm and exhibiting red color was formed.

Then, the heating boat containing Alq ₃ was energized and heated to vapor-deposit at a vapor deposition rate of 0.1 nm / sec to form an electron transport (ETL) layer having a layer thickness of 25 nm.

Further, LiF was vapor-deposited at a vapor deposition rate of 0.1 nm / sec to form an electron-injected layer (EIL) having a layer thickness of 1 nm.

(Formation of the second electrode)
Next, aluminum was vapor-deposited to a thickness of 70 nm to form a second electrode (cathode; reflective electrode, light opaque) to produce a light emitting element 101.

(Formation of organic functional layer for light receiving element)
Subsequently, the pattern mask for forming the light emitting area was replaced with the pattern mask for forming the light receiving area, molybdenum oxide (MoO ₃ ) was vapor-deposited on the first electrode at a vapor deposition rate of 0.1 nm / sec, and electrons having a layer thickness of 7 nm were deposited. A blocking layer (EBL) was formed.

Next, the compound DBP represented by the following chemical formula was vapor-deposited at a vapor deposition rate of 0.1 nm / sec to form a hole transport layer having a film thickness of 10 nm.

Then a compound DBP deposition rate 0.1 nm / sec, at the same time the following fullerene _{C 60} was deposited at a deposition rate of 0.2 nm / sec, thickness 40 nm, Compound DBP and fullerene _{C 60} is a volume ratio of 1: 2 to become light A layer was formed. The light receiving layer had a donut shape with an outer diameter of 4.3 mm and an inner diameter of 1.8 mm and surrounded the light emitting element, and had an area of 0.47 cm ² .

Next, fullerene C ₆₀ was vapor-deposited at a vapor deposition rate of 0.1 nm / sec to form an electron transport layer having a film thickness of 20 nm.
Next, BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) was deposited at a vapor deposition rate of 0.1 nm / sec to form a hole blocking layer having a film thickness of 6 nm.

(Formation of second electrode layer)
Next, aluminum was vapor-deposited to a thickness of 70 nm to form a second electrode layer (cathode; reflective electrode, light opaque) to produce a light receiving element 101.

(Seal of element)
Finally, the light emitting element 101 and the light receiving element 101 obtained above are covered with a glass case, a glass substrate having a thickness of 700 μm is used as a sealing member, and an epoxy-based photocurable adhesive (Toa Synthetic Co., Ltd.) is used as a sealing material around the glass substrate. (Lux Track LC0629B) manufactured by Lax Track LC0629B) is applied, the second extraction electrode part and the substrate of the element are brought into close contact with each other, UV light is irradiated from the glass substrate side, cured and sealed, and the light is emitted adjacently on the same surface for comparison. The light receiving element 101 was manufactured.

<Manufacturing of adjacently arranged light emitting and receiving elements 102 on the same surface>
In the production of the on-same surface adjacent arrangement type light emitting and receiving element 101, the same is true except that the sizes of the light emitting element and the light receiving element are changed as shown in Table I. 102 was made.

<Manufacturing of laminated light emitting and receiving element 201>
According to the following method, a light emitting element 201 and a light receiving element 201, which are organic EL elements having the configuration shown in FIG. 2, were manufactured. The area of the light emitting element 201 is a circle having a radius of 1.5 mm and an area of 0.07 cm ² by adjusting the mask. Further, the area of the light receiving element 201 has a radius of 3.9 mm and an area of 0.47 cm ² by adjusting the mask (formation of a take-out electrode).
ITO (In ₂ O ₃ : SnO ₂ = 90:10 (mass% ratio)) is formed on a transparent glass substrate (30 mm × 30 mm) by a sputtering method under the condition that the thickness is 150 nm, and then patterning is performed. To form a take-out electrode made of an ITO layer for feeding.

(Formation of base layer)
Using a pattern mask for vapor deposition having an opening of the same size as the sealing area, the following compound 1 was vapor-deposited at a vapor deposition rate of 0.1 nm / sec according to a conventional method to form a base layer having a film thickness of 15 nm. ..

(Formation of anode for light emitting element)
The pattern mask for thin film deposition was replaced with one for light emitting element anode vapor deposition, and silver was vapor-deposited at a vapor deposition rate of 0.3 nm / sec to form an anode layer which is a first electrode having a film thickness of 12 nm.

(Formation of organic functional layer for light emitting element)
The pattern mask is replaced with one for forming a light emitting area, and the organic functional layers (HIL, HTL, EBL, EIL and ETL) including the light emitting layer are vapor-deposited in the same manner as the formation of the light emitting element 101, and the organic function for the light emitting element is formed. A layer was formed.

(Formation of cathode and bridge electrodes)
The pattern mask was replaced with a cathode for a light emitting element and one for a bridge electrode, and aluminum was vapor-deposited at a vapor deposition rate of 0.3 nm / sec according to a conventional method to form a cathode and a bridge electrode for the light emitting element 201 having a film thickness of 100 nm. As a result, the anode for the light emitting element and the take-out ITO electrode for the anode were electrically connected.

(Formation of intermediate insulating layer)
The pattern mask was replaced with the mask for forming the base layer, and the compound (38) described in Japanese Patent No. 6241193 was vapor-deposited at a vapor deposition rate of 0.1 nm / sec according to a conventional method to form an intermediate insulating layer having a film thickness of 70 nm. Formed.

(Formation of anode for light receiving element)
The pattern mask for thin film deposition was replaced with one for light receiving element anode deposition, and an anode layer having a film thickness of 12 nm was formed by vapor deposition silver at a vapor deposition rate of 0.3 nm / sec according to a conventional method.

(Formation of organic functional layer for light receiving element)
The pattern mask was replaced with one for forming a light receiving area, and vapor deposition was performed in the same manner as for forming the organic functional layer of the light receiving element 101 to form the organic functional layer of the light receiving element 201.

(Formation of cathode and bridge electrodes)
The pattern mask was replaced with a cathode for a light receiving element and one for a bridge electrode, and aluminum was vapor-deposited at a vapor deposition rate of 0.3 nm / sec according to a conventional method to form a cathode and a bridge electrode for the light receiving element 201 having a film thickness of 100 nm. As a result, the anode for the light receiving element and the take-out ITO electrode for the anode were electrically connected.

(Seal of element)
Finally, the element obtained above is covered with a glass case, a glass substrate having a thickness of 700 μm is used as a sealing member, and an epoxy-based photocurable adhesive (Luxtrac LC0629B manufactured by Toa Synthetic Co., Ltd.) is applied as a sealing material around it. The laminated light emitting and receiving element 201 of the present invention was produced by applying it, bringing the second extraction electrode portion and the substrate of the element into close contact with each other, irradiating UV light from the glass substrate side, curing and sealing the mixture.

<Manufacturing of laminated light emitting and receiving element 202>
In the production of the laminated light emitting / receiving element 201, the laminated light emitting / receiving element 202 of the present invention was produced in the same manner except that the sizes of the light emitting element and the light receiving element were changed as shown in Table I.

<Manufacturing of laminated light emitting and receiving element 301>
A light emitting element 301 and a light receiving element 301, which are organic EL elements having the configuration shown in FIG. 3, were produced according to the following method. The area of the light emitting element 301 is a circle having a radius of 1.5 mm and an area of 0.07 cm ² by adjusting the mask. Further, the area of the light receiving element 301 has a radius of 4.2 mm and an area of 0.55 cm ² by adjusting the mask (formation of a take-out electrode).
ITO (In ₂ O ₃ : SnO ₂ = 90:10 (mass% ratio)) is formed on a transparent glass substrate (30 mm × 30 mm) by a sputtering method under the condition that the thickness is 150 nm, and then patterning is performed. To form an anode of the light receiving element area made of ITO, a take-out electrode connected to the anode, and a take-out electrode made of ITO for feeding the light receiving element.

(Formation of organic functional layer for light receiving element)
The pattern mask was replaced with one for forming a light receiving area, and vapor deposition was performed in the same manner as the light receiving element 101 to form an organic functional layer for the light receiving element 301.

(Formation of cathode and bridge electrodes)
The pattern mask was replaced with a cathode for a light receiving element and one for a bridge electrode, and aluminum was vapor-deposited at a vapor deposition rate of 0.3 nm / sec according to a conventional method to form a cathode for a light receiving element and a bridge electrode having a film thickness of 100 nm. As a result, the anode for the light receiving element and the take-out ITO electrode for the anode were electrically connected.

(Formation of intermediate insulating layer)
The pattern mask was replaced with the mask for forming the base layer, and the compound (38) described in Japanese Patent No. 6241193 was vapor-deposited at a vapor deposition rate of 0.1 nm / sec according to a conventional method to form an intermediate insulating layer having a film thickness of 70 nm. Formed.

(Formation of anode for light emitting element)
The pattern mask for thin film deposition was replaced with one for light emitting element anode vapor deposition, and an anode layer having a thickness of 12 nm was formed by vapor deposition silver at a vapor deposition rate of 0.3 nm / sec according to a conventional method.

(Formation of organic functional layer for light emitting element)
The pattern mask was replaced with one for forming a light emitting area, and vapor deposition was performed in the same manner as for the light emitting element 101 to form an organic functional layer for the light emitting element 301.

(Formation of cathode and bridge electrodes)
The pattern mask was replaced with one for a cathode for a light emitting element and one for a bridge electrode, and aluminum was vapor-deposited at a vapor deposition rate of 0.3 nm / sec according to a conventional method to form a cathode for a light emitting element and a bridge electrode having a film thickness of 100 nm. As a result, the anode for the light emitting element and the take-out ITO electrode for the anode were electrically connected.

(Seal of element)
Finally, the element obtained above is covered with a glass case, a glass substrate having a thickness of 700 μm is used as a sealing member, and an epoxy-based photocurable adhesive (Luxtrac LC0629B manufactured by Toa Synthetic Co., Ltd.) is applied as a sealing material around it. The laminated light emitting and receiving element 301 of the present invention was produced by applying, bringing the take-out electrode portion and the substrate of the element into close contact with each other, irradiating UV light from the glass substrate side, curing and sealing the mixture.

<Manufacturing of laminated light emitting and receiving element 302>
In the production of the laminated light emitting / receiving element 301, the laminated light emitting / receiving element 302 of the present invention was produced in the same manner except that the sizes of the light emitting element and the light receiving element were changed as shown in Table I.

Table I shows the components of the light emitting / receiving element produced above.

From FIGS. 1 to 3 and Table I, the stacked light emitting and receiving elements 201, 202, 301 and 302 of the present invention are comparative examples in which a plurality of devices are arranged on the same plane and adjacent to each other. In No. and 102, the gap portion between the devices does not function, and the emission brightness and the light receiving sensitivity are limited. However, by making the stack type as in the present invention, such a problem is solved, and the emission brightness and the light receiving sensitivity are solved. It can be seen that the sensitivity can be maximized. Further, it can be seen that the stacking of the OLED and the OPV facilitates the optimization of the light emitting area and the light receiving area.

[Example 2]
<Manufacturing of laminated light emitting and receiving element 401>
According to the following method, a light emitting element 401 and a light receiving element 401, which are organic EL elements having the configuration shown in FIG. 6B, were produced. The area of the light emitting element 401 is a circle having a radius of 1.5 mm and an area of 0.07 cm ² by adjusting the mask. The area of the light receiving element 401 is a radius of 3.9 mm and an area of 0.47 cm ² by adjusting the mask (formation of a take-out electrode).
As a transparent substrate, a polyester film MELINEX ST504 (manufactured by Teijin DuPont Film Co., Ltd.) having a width of 50 cm and a thickness of 125 μm was prepared. This polyester film is heated to 80 ° C. under a reduced pressure of 1.33 Pa and degassed for 3 hours.

A polysilazane-containing coating liquid was applied onto the polyester film, and then vacuum ultraviolet rays were irradiated to perform a reforming treatment to provide a gas barrier layer to prepare a transparent flexible substrate.

(Preparation of coating solution containing polysilazane)
A dibutyl ether solution containing 20% by mass of uncatalyzed perhydropolysilazane (Aquamica® NN120-20, manufactured by AZ Electronic Materials Co., Ltd.) and an amine catalyst (N, N, N', N'-tetramethyl- A dibutyl ether solution of 20% by mass of perhydropolysilazane containing 5% by mass of 1,6-diaminohexane (TMDAH) (Aquamica® NAX120-20, manufactured by AZ Electronic Materials Co., Ltd.) at 4: 1. The coating solution is mixed in a ratio and further mixed so that the mass ratio of dibutyl ether and 2,2,4-trimethylpentane is 65:35 so that the solid content of the coating solution is 5% by mass. Was diluted and prepared.

The coating liquid obtained above is formed on the transparent substrate with a spin coater so as to have a thickness of 300 nm, left for 2 minutes, and then heat-treated on a hot plate at 80 ° C. for 1 minute to coat with polysilazane. A film was formed.

After forming the polysilazane coating film, a vacuum ultraviolet irradiation treatment of 6000 mJ / cm ² was performed to form a gas barrier layer.

ITO (In ₂ O ₃ : SnO ₂ = 90:10 (mass% ratio)) is formed on the polyester film with a gas barrier layer by a sputtering method under the condition that the thickness is 150 nm, and then patterning is performed to perform ITO. A take-out electrode for feeding was formed composed of layers.

(Formation of base layer)
Using a pattern mask for vapor deposition having an opening of the same size as the sealing area, the compound A was vapor-deposited at a vapor deposition rate of 0.1 nm / sec according to a conventional method to form a base layer having a film thickness of 15 nm. ..

(Formation of anode for light emitting element)
The pattern mask for thin film deposition was replaced with one for light emitting element anode vapor deposition, and silver was vapor-deposited at a vapor deposition rate of 0.3 nm / sec to form an anode layer which is a first electrode having a film thickness of 12 nm.

(Formation of Organic Functional Layer-1 for Light Emitting Element)
The pattern mask is replaced with one for forming a light emitting area, and the organic functional layers (HIL, HTL, EBL, EIL and ETL) including the light emitting layer are vapor-deposited in the same manner as the formation of the light emitting element 101, and the organic function for the light emitting element is formed. Layer-1 was formed.

(Formation of light transmissive intermediate electrode)
Aluminum (Al) and silver (Ag) were placed in a tungsten resistance heating boat, respectively, and mounted in a vacuum chamber. After depressurizing the vacuum chamber to 4 × 10 ^-4 Pa, the resistance heating boats are independently energized and heated to form a light-transmitting intermediate electrode having a thickness ratio of aluminum (Al) 1 nm and silver (Ag) 12 nm. It was formed on the electron transport layer by co-evaporation.

(Formation of organic functional layer-2 for light emitting element)
In the formation of the organic functional layer-1 for a light emitting element, phosphorescence having a film thickness of 20 nm is exhibited by using a light emitting dopant represented by the following GD-1 (green light emitting property) instead of the light emitting dopant RD-1. The organic functional layers (HIL, HTL, EBL, EIL and ETL) including the light emitting layer were vapor-deposited in the same manner except that the light emitting layer (EML) was formed to form the organic functional layer-2 for the light emitting element.

(Formation of cathode and bridge electrodes)
The pattern mask was replaced with a cathode for a light emitting element and one for a bridge electrode, and aluminum was vapor-deposited at a vapor deposition rate of 0.3 nm / sec according to a conventional method to form a cathode and a bridge electrode for the light emitting element 401 having a film thickness of 100 nm. As a result, the anode for the light emitting element and the take-out ITO electrode for the anode were electrically connected.

(Formation of intermediate insulating layer)
The pattern mask was replaced with the mask for forming the base layer, and the compound (38) described in Japanese Patent No. 6241193 was vapor-deposited at a vapor deposition rate of 0.1 nm / sec according to a conventional method to form an intermediate insulating layer having a film thickness of 70 nm. Formed.

(Formation of anode for light receiving element)
The pattern mask for thin film deposition was replaced with one for light receiving element anode vapor deposition, and an anode layer having a film thickness of 12 nm was formed by vapor deposition silver at a vapor deposition rate of 0.3 nm / sec according to a conventional method.

(Formation of organic functional layer for light receiving element)
The pattern mask was replaced with one for forming a light receiving area, and vapor deposition was performed in the same manner as for forming the organic functional layer of the light receiving element 101 to form the organic functional layer of the light receiving element 401.

(Formation of cathode and bridge electrodes)
The pattern mask was replaced with a cathode for a light receiving element and one for a bridge electrode, and aluminum was vapor-deposited at a vapor deposition rate of 0.3 nm / sec according to a conventional method to form a cathode and a bridge electrode for the light receiving element 201 having a film thickness of 100 nm. As a result, the anode for the light receiving element and the take-out ITO electrode for the anode were electrically connected.

(Seal of element)
Finally, using the polyester film with the gas barrier layer as a sealing member, an epoxy-based photocurable adhesive (Lux Track LC0629B manufactured by Toa Synthetic Co., Ltd.) was applied as a sealing material to the element obtained above. The take-out electrode portion and the substrate of the element were brought into close contact with each other, irradiated with UV light from the substrate side, cured and sealed to produce the laminated light emitting and receiving element 401 of the present invention.

Next, the produced laminated light-emitting light receiving element 401 was moved to a nitrogen atmosphere again and cut to a specified size using an ultraviolet laser.

The cut laminated light emitting / receiving element was attached to a reflective pulse oximeter that can be wrapped around the wrist shown in FIG. The pulse oximeter constantly outputs a constant amount of red and green light to irradiate the inside of the living body, and the amount of reflected light changes depending on the amount of hemoglobin that binds to oxygen flowing in the blood. The oxygen concentration in the blood of the subject could be measured through the measurement analyzer connected by the take-out wiring.

Since the reflective pulse oximeter of the present invention can be wrapped around the wrist, the subject can measure without feeling the weight and annoyance of a conventional transmissive pulse oximeter worn on a fingertip.

1 Translucent substrate 2, 2-1 Light-transmitting first electrode 2-2 Light-transmitting intermediate electrode 3 Light-emitting element (OLED)
3-1 Red light emitting element 3-2 Green light emitting element 4 Light reflecting second electrode 5 Light receiving element (OPV)
6 Light-transmitting third electrode 7 Light-reflecting fourth electrode 8 Adhesive layer 9 Encapsulant 10 Adjacent arrangement type light emitting and receiving element 20, 30, 40, 50-1, 50-2 Stacked type light emitting and receiving element 11 -1, 11-2 Intermediate insulation layer 12 Non-translucent substrate 13 Translucent encapsulant 60 Reflective pulse oximeter 61 Substrate 62 Stacked light emitting and receiving element 63 Band 64 Magic tape (registered trademark)
100 Organic EL element 101 Base material 102 Anode 103 Hole injection layer 104 Hole transport layer 105 Light emitting layer 106 Block layer 107 Electron transport layer 108 Electron injection layer 109 Cathode 200 Bulk heterojunction type organic photoelectric conversion element 201 Substrate 202 Transparent electrode ( anode)
203 Counter electrode (cathode)
204 Photoelectric conversion layer (bulk heterojunction layer)
207 Hole transport layer 208 Electron transport layer

Claims (8)

It is a laminated light emitting and receiving element in which a planar light emitting element and a light receiving element are laminated.
A stacked light emitting and receiving element, wherein the light receiving element receives the reflected light of the light emitted by the light emitting element. The stacked light emitting and receiving element according to claim 1, wherein the light emitting element emits light having a plurality of different wavelengths. The stacked light emitting / receiving element according to claim 1 or 2, wherein the light emitting element is arranged on the light emitting surface side. The laminated light emitting and receiving device according to any one of claims 1 to 3, wherein the light transmitting substrate, the light emitting element, the intermediate insulating layer, the light receiving element, and the sealing layer are formed in this order. element. The laminated light-emitting light-receiving element according to claim 1 or 2, wherein the light-transmitting substrate, the light-receiving element, the intermediate insulating layer, the light-emitting element, and the sealing layer are configured in this order. The laminated light emitting and receiving device according to any one of claims 1 to 3, wherein the substrate, a light receiving element, an intermediate insulating layer, a light emitting element, and a light transmitting sealing layer are configured in this order. element. An electronic device comprising the stacked light emitting and receiving element according to any one of claims 1 to 6. The electronic device according to claim 7, wherein the electronic device is a reflective pulse oximeter.

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