FR3113189A1 - Oximeter - Google Patents

Abstract

Title: Oximeter. The invention: A method of manufacturing an oximeter comprising a substrate (2) and a common upper electrode (3), an assembly of three separate stacks (10) comprising a first electroluminescent stack (110); a second light emitting stack (130) and a photoreceptor stack (120); the set of three stacks (10) being configured so as to be ordered between a substrate (2) and a common upper electrode (3). Figure for abstract: Fig.2

Description

Oximeter

The present invention relates to the field of flexible organic light-emitting diodes (OLEDs) and organic photodetectors (OPDs), in particular for measuring heart rate, blood pressure and blood oxygenation rate. The present invention also relates to a method for producing such a flexible organic device for monitoring and controlling physiological parameters and/or chronic wounds. It finds a particularly advantageous application in the field of oximeters.

STATE OF THE ART

The use of OLEDs and OPDs in the medical field remains limited. The need for a surface organic light source, integrated with a flexible OPD, both manufactured on the same support and for oximetry measurements, is strongly expressed by health professionals. This need is particularly expressed for the monitoring and control of chronic wounds.

Monitoring the healing of wounds in diabetic patients, for example, is essential for nursing staff to ensure that the wound is progressing well until complete healing.

This follow-up is generally done when the dressing is replaced thanks to a visual check of the surface and depth aspect of the wound. The visual control can be carried out either directly by a qualified operator or remotely by a doctor thanks to digital imaging.

Regular monitoring is also necessary to ensure that the wound is not becoming infected or becoming necrotic, which could lead to serious complications such as gangrene and/or amputation at term.

To date, no local physiological parameter is regularly measured within and on the periphery of wounds in order to provide additional visual analysis.

However, certain physiological data are likely to provide useful information for medical decision-making for a patient, such as the implementation of a revascularizing treatment or antibiotic prophylaxis.

In addition, it has been shown that a localized measurement of pressure, temperature, humidity or blood oxygenation can provide precise information on the evolution of a wound.

This information can help caregivers in a home care strategy, such as defining a frequency of dressing replacement and/or wound cleaning to optimize the healing phase.

In addition, by identifying wounds at risk of complications in advance, in particular those that are getting worse, this would allow doctors to act earlier either by recommending a curative treatment or by adapting the treatment in progress.

Oximetry is a non-invasive medical detection method for measuring heart rate, blood pressure, and blood oxygen levels.

Conventional oximeters use expensive optoelectronic components. These components are generally formed by light-emitting diodes (LEDs) and inorganic photo-detectors which contain toxic materials (heavy metals). They are generally rigid and they are complex to use because of their positioning at the fingertips or at the ears.

The need for a flexible and light oximeter that can be placed almost anywhere on the human body is therefore a necessity in several areas and especially for the control and monitoring of vital parameters in patients who suffer from chronic wounds such as diabetic foot sores or pressure sores, hypertension or heart problems for example.

The measurement of “functional” arterial oxygen saturation (SaO2) is initially the main objective of oximeter measurements.

The measurement of arterial oxygen saturation is calculated from the photoplethysmographic signal (PPG) and given by the following formula:

In order to approximate the measurement of arterial oxygen saturation, a pulse oximetry (SpO2) device must continuously determine the oxyhemoglobin (HbO2) and hemoglobin (Hb) content of arterial blood.

A device configured so as to measure continuously and in real time the blood oxyhemoglobin (HbO2) and hemoglobin (Hb) content and then to recognize the pulsatility of the signal demonstrating its arterial origin, is therefore necessary.

In addition, it should be noted that oxyhemoglobin (HbO2) shows better absorption in infrared or near infrared wavelengths, from 820 nm to 1000 nm, while hemoglobin (Hb) shows better absorption. in the red wavelength spectrum from 600 nm to 750 nm.

There are several flexible oximeter technologies using OLEDs and OPDs that have appeared in recent years, however they are essentially limited to a dedicated application for basic laboratory research.

Their main drawback is their low thermal stability, especially during sterilization at high temperature such as for example at temperatures above 80°C.

Another defect encountered relates to the flexible substrate used. Most flexible substrates are PET or PEN substrates. These substrates suffer from their low extensibility, a parameter that is nevertheless necessary for integration into the dressings of chronic wounds.

Another defect encountered concerns infrared and near infrared OLEDs above a wavelength greater than 800 nm, these OLEDs have a very low quantum efficiency of less than 1%.

Another defect encountered is the electrical connection system of OLEDs and OPDs.

Indeed, OLEDs and OPDs are two devices that are generally manufactured on rigid supports and are then transferred to flexible supports. This generally does not allow easy electrical connection and therefore limits the range of positioning possibilities on the human body.

In parallel with these devices, there are other technical solutions such as the one disclosed in the document US20130075761 A1. It is a photoelectric conversion device which includes a substrate having opaque interconnect layers, an insulating film on the substrate having a plurality of openings, light-receiving elements which form openings, and light-emitting elements .

The technical solution disclosed in US20130075761 A1, with regard to light-emitting stacks, makes use of transparent anodes made of ITO (acronym for tin and indium oxide), and has a relatively complex structure.

An object of the present invention is therefore to propose a solution which makes it possible to eliminate or limit at least one of the aforementioned drawbacks.

The other objects, features and advantages of the present invention will become apparent from a review of the following description and the accompanying drawings. It is understood that other benefits may be incorporated.

SUMMARY

• un premier empilement électroluminescent comprenant successivement :
  • une première électrode ;
  • une première couche organique de transport de trous ;
  • une première couche organique active ;
  • une première couche organique de transport d’électrons ;
• un deuxième empilement électroluminescent comprenant successivement :
  • une deuxième électrode ;
  • une deuxième couche organique de transport de trous ;
  • une deuxième couche organique active ;
  • une deuxième couche organique de transport d’électrons ;
• un empilement photorécepteur comprenant successivement :
  • une électrode transparente ;
  • une troisième couche organique de transport de trous ;
  • une couche organique photo réceptrice ;
  • une troisième couche organique de transport d’électrons ;

l’ensemble de trois empilements étant configuré de sorte à être ordonné entre un substrat commun et une électrode supérieure commune, de sorte que :

• la première couche de transport de trous, la deuxième couche organique de transport de trous et la troisième couche organique de transport de trous sont réalisées en un même matériau afin d’être fabriquée simultanément,
• la première couche organique de transport d’électrons, la deuxième couche organique de transport d’électrons et la troisième couche organique de transport d’électrons sont réalisées en un même matériau afin d’être fabriquée simultanément,
• la première électrode et la deuxième électrode sont semi-réfléchissantes de sorte à former au moins une première microcavité et au moins une seconde microcavité,
• l’épaisseur de la première couche organique de transport de trous est inférieure à l’épaisseur de la deuxième couche organique de transport de trous et/ou l’épaisseur de la première couche organique de transport d’électrons est inférieure ou égale à l’épaisseur de la deuxième couche organique de transport d’électrons.

To achieve this objective, according to one embodiment, there is provided a method of manufacturing an oximeter comprising a substrate and a common upper electrode and located between the substrate and the common upper electrode, a set of separate stacks comprising:

• a first electroluminescent stack successively comprising:
  • a first electrode;
  • a first organic hole transport layer;
  • a first active organic layer;
  • a first organic electron transport layer;
• a second electroluminescent stack successively comprising:
  • a second electrode;
  • a second organic hole transport layer;
  • a second active organic layer;
  • a second organic electron transport layer;
• a photoreceptor stack successively comprising:
  • a transparent electrode;
  • a third organic hole transport layer;
  • an organic photo-receptive layer;
  • a third organic electron transport layer;

the set of three stacks being configured so as to be ordered between a common substrate and a common upper electrode, such that:

• the first hole transport layer, the second organic hole transport layer and the third organic hole transport layer are made of the same material in order to be manufactured simultaneously,
• the first organic electron transport layer, the second organic electron transport layer and the third organic electron transport layer are made of the same material in order to be manufactured simultaneously,
• the first electrode and the second electrode are semi-reflecting so as to form at least a first microcavity and at least a second microcavity,
• the thickness of the first organic hole transport layer is less than the thickness of the second organic hole transport layer and/or the thickness of the first organic electron transport layer is less than or equal to thickness of the second organic electron transport layer.

Without the present invention, it would be necessary to succeed in proposing a device, adaptable to all types of surfaces of the human body; allowing measurements comparable to those carried out using known devices of the state of the art such as those which are positioned at the end of the finger.

In addition, a technical solution would have to be found to optimize the manufacturing process of said device.

Preferably, the present invention relates to the use of a flexible and extensible substrate preferably comprising parylene or polyparaxylylene and/or polyurethane.

Therefore, the present invention makes it possible to optimize the manufacture of an oximetry device comprising at least one photodiode and at least two OLEDs comprising resonance cavities.

Indeed, the resonance cavities advantageously make it possible to obtain measurements similar to products sold commercially in transmission mode at the fingertip.

The use of these cavities makes it possible to play on the resonance peak to adjust the light emitted rather than having to necessarily differentiate the nature of the materials of the two OLEDs.

• un premier empilement électroluminescent comprenant successivement :
  • une première électrode ;
  • une première couche organique de transport de trous ;
  • une première couche organique active ;
  • une première couche organique de transport d’électrons ;
• un deuxième empilement électroluminescent comprenant successivement :
  • une deuxième électrode ;
  • une deuxième couche organique de transport de trous ;
  • une deuxième couche organique active ;
  • une deuxième couche organique de transport d’électrons ;
• un empilement photorécepteur comprenant successivement :
  • une électrode transparente ;
  • une troisième couche organique de transport de trous ;
  • une couche organique photo réceptrice ;
  • une troisième couche organique de transport d’électrons ;

l’ensemble de trois empilements étant configuré de sorte à être ordonné entre un substrat commun et une électrode supérieure commune de sorte que :

• la première couche de transport de trous, la deuxième couche organique de transport de trous et la troisième couche organique de transport de trous sont composées du même matériau
• la première couche organique de transport d’électrons, la deuxième couche organique de transport d’électrons et la troisième couche organique de transport d’électrons sont composées du même matériau,
• la première électrode et la deuxième électrode sont semi-réfléchissantes de sorte à former au moins une première microcavité et au moins une seconde microcavité,
• l’épaisseur de la première couche organique de transport de trous est inférieure à l’épaisseur de la deuxième couche organique de transport de trous et/ou l’épaisseur de la première couche organique de transport d’électrons est inférieure ou égale à l’épaisseur de la deuxième couche organique de transport d’électrons.

Another aspect therefore relates to an oximetry device which comprises a substrate and a common upper electrode and located between the substrate and the common upper electrode, a set of three separate stacks comprising:

• a first electroluminescent stack successively comprising:
  • a first electrode;
  • a first organic hole transport layer;
  • a first active organic layer;
  • a first organic electron transport layer;
• a second electroluminescent stack successively comprising:
  • a second electrode;
  • a second organic hole transport layer;
  • a second active organic layer;
  • a second organic electron transport layer;
• a photoreceptor stack successively comprising:
  • a transparent electrode;
  • a third organic hole transport layer;
  • an organic photo-receptive layer;
  • a third organic electron transport layer;

the set of three stacks being configured so as to be ordered between a common substrate and a common upper electrode such that:

• the first hole transport layer, the second organic hole transport layer and the third organic hole transport layer are made of the same material
• the first organic electron transport layer, the second organic electron transport layer and the third organic electron transport layer are composed of the same material,
• the first electrode and the second electrode are semi-reflecting so as to form at least a first microcavity and at least a second microcavity,
• the thickness of the first organic hole transport layer is less than the thickness of the second organic hole transport layer and/or the thickness of the first organic electron transport layer is less than or equal to thickness of the second organic electron transport layer.

According to a particular embodiment, the invention relates to a medical dressing comprising an organic oximetry device according to any one of the preceding claims as well as an adhesive surface.

By offering a device associated with a medical dressing capable of regularly measuring and transmitting predictive data on the evolution of healing to the nursing staff, the quality of wound care in patients is advantageously improved.

BRIEF DESCRIPTION OF FIGURES

The aims, objects, as well as the characteristics and advantages of the invention will emerge better from the detailed description of an embodiment, of the latter which is illustrated by the following accompanying drawings in which:

There shows the device according to one embodiment, the oximetry device comprising a photoreceptor stack between a first light-emitting stack and a second light-emitting stack.

There shows a vertical sectional view of the device shown in .

There represents, according to one embodiment, the structure of a light-emitting organic electrode, preferably an anode.

There represents, according to one embodiment, the structures of the light-emitting stacks and of the photoreceptor stack.

There represents, according to one embodiment, the variation in resonance as a function of the thickness of a hole transport layer.

There represents, according to one embodiment, the emission spectrum of a light-emitting diode as a function of the material likely to compose a cathode.

The drawings are given by way of examples and do not limit the invention. They constitute schematic representations of principle intended to facilitate understanding of the invention and are not necessarily scaled to practical applications.

DETAILED DESCRIPTION

Before starting a detailed review of embodiments of the invention, optional characteristics are set out below which may possibly be used in combination or alternatively.

According to one example, the set of three stacks is made so that the sum of the thickness of the first organic hole transport layer with the thickness of the first organic electron transport layer is strictly less than the sum thicknesses of the second organic hole transport layer and of the second organic electron transport layer, so that the first microcavity has a first resonance peak different from a second resonance peak of the second microcavity.

Indeed, within the same electroluminescent stack, the sum of the thickness of the organic hole transport layer with the thickness of the organic electron transport layer preferentially conditions the value of the corresponding wavelength to the resonance peak associated with said electroluminescent stack.

According to one example, all three stacks are made so that the thickness of the first organic hole transport layer is equal to the thickness of the second organic hole transport layer and the thickness of the first layer organic electron transport layer is greater than the thickness of the second organic electron transport layer, so that the first microcavity has a first resonance peak different from a second resonance peak of the second microcavity.

Indeed, this makes it possible to advantageously produce simultaneously and in the same material the first organic layer for transporting holes and the second organic layer for transporting holes.

Thus, the manufacturing process is for example optimized from the point of view of the production steps.

According to one example, all three stacks are made such that the thickness of the first organic hole transport layer is less than the thickness of the second organic hole transport layer and the thickness of the first layer organic electron transport layer is equal to the thickness of the second organic electron transport layer, so that the first microcavity has a first resonance peak different from a second resonance peak of the second microcavity.

Indeed, this makes it possible to advantageously produce simultaneously and in the same material the first organic electron transport layer and the second organic electron transport layer.

Thus, the manufacturing process is for example optimized from the point of view of the production steps.

• soit l’épaisseur de la première couche organique de transport de trous est égale à l’épaisseur de la deuxième couche organique de transport de trous et est égale à l’épaisseur de la troisième couche organique de transport de trous.
• soit l’épaisseur de la première couche organique de transport d’électrons est égale à l’épaisseur de la deuxième couche organique de transport d’électrons et est égale à l’épaisseur de la troisième couche organique de transport d’électrons.

Method of manufacturing an oximeter according to any one of the preceding claims, in which the set of three stacks is made so that:

• or the thickness of the first organic hole transport layer is equal to the thickness of the second organic hole transport layer and is equal to the thickness of the third organic hole transport layer.
• or the thickness of the first organic electron transport layer is equal to the thickness of the second organic electron transport layer and is equal to the thickness of the third organic electron transport layer.

Indeed, this makes it possible to advantageously produce simultaneously and in the same material the first organic layer for transporting holes, the second organic layer for transporting holes and the third organic layer for transporting holes or else, in the same way , this makes it possible to advantageously produce simultaneously and in the same material the first organic electron transport layer, the second organic electron transport layer and the third organic electron transport layer

Thus, the manufacturing process is for example optimized from the point of view of the production steps.

According to one example, the first electroluminescent stack emits light waves whose wavelengths are greater than 600 nm and/or less than 750 nm.

This preferably allows emission of light waves in the red spectrum, the wavelengths of which are advantageously conducive to the absorption of hemoglobin.

Indeed, it should be noted that, for example, hemoglobin absorbs more wavelengths located between 600 nm and 750 nm.

According to one example, the second electroluminescent stack emits light waves whose wavelengths are greater than 820 nm and/or less than 1000 nm.

This preferably allows emission of light waves in the infrared spectrum, the wavelengths of which are advantageously conducive to the absorption of oxyhemoglobin.

Indeed, it should be noted that, for example, oxyhaemoglobin absorbs more wavelengths located between 820 nm and 1000 nm.

According to one example, the electrical connectors are printed by inkjet in order to optimize the thickness of the device.

This responds to the problem of lowering manufacturing costs.

Indeed, inkjet printing of electrical connectors and for example the use of CMOS packaging electronics advantageously allows almost instantaneous implementation to be envisaged since the masking steps or the subtractive and subtractive processes are thus eliminated. preferentially without spending excess raw material and lowers the manufacturing cost.

According to one example, the first electrode and the second electrode are formed with a successive sequence of ZnO/Ag/Ti/ZnO layers.

This makes it possible to advantageously increase the quantum yields by the generation of resonant cavities, preferably beyond an emission greater than 630nm.

Indeed, the first layer of zinc oxide (ZnO) deposited on the flexible substrate preferentially improves the adhesion of the Ag layer on the flexible substrate.

In addition, the silver (Ag) layer, for its part, advantageously improves the conductivity of the TCO of the English acronym “Transparent Conductive Oxides” which can be translated as transparent conductive oxide layer.

Finally, the titanium (Ti) layer is used, for example, to ensure better interconnection with the second layer of ZnO used preferentially for the injection of positive charge carriers.

According to one example, the thickness of the first organic hole transport layer is greater than 220 nm and/or less than 260 nm, the thickness of the second organic hole transport layer is greater than 300 nm and/or less at 360 nm, the thickness of the third organic hole transport layer is greater than 54 nm and/or less than 66 nm.

This responds to the problem of optimizing the implementation of the process.

Thus, the three stacks can for example comprise layers of the same nature deposited at the same time whether it is within the first electroluminescent stack, the second electroluminescent stack or the photoreceptor stack.

According to one example, the device of the present invention comprises at least two sets of three separate stacks.

This makes it possible, according to one embodiment, to extend the oximetry device over a larger detection surface.

According to one example, the thickness of the first organic electron transport layer is equal to the thickness of the second organic electron transport layer which is equal to the thickness of the third organic electron transport layer and is preferably equal to 60 nm.

This once again responds to the problem of optimizing the implementation of the process.

Thus, the three stacks can for example comprise layers of the same nature and of the same thicknesses, deposited at the same time whether within the first electroluminescent stack, the second electroluminescent stack or the photoreceptor stack.

According to one example, the common upper electrode is composed of silver and whose thickness is preferably equal to 100 nm.

This allows, according to one embodiment, the device to have better efficiency compared to an electrode which will preferably be a silver cathode.

According to one example, the common upper electrode is made of aluminum and whose thickness is preferably equal to 100 nm.

According to one example, the first active layer, the second active layer and the photoreceptive layer are of the same thickness, preferably 20 nm.

This once again responds to the problem of optimizing the implementation of the process.

Thus, the first electroluminescent stack and the second electroluminescent stack can for example comprise layers of the same thicknesses and of the same natures, deposited at the same time and of the same thickness as the photoreceptor layer of the photoreceptor stack.

According to one example, the electron transport layer may be formed by an organic host material and an organic P-type electrical dopant. The electrical doping of the host matrix is preferably N-type.

According to one example, a buffer layer is positioned between at least the set of three stacks and the common upper electrode, it is preferably a LiF layer with a thickness of 1 nm.

This promotes charge injection by tunnel effect.

According to one example, the substrate is made of a transparent material having a property allowing it to be flexible and extensible so as to be able to adapt to the surfaces of the skin.

This responds to the problem of integrating the device into a patch or a flexible dressing that can conform to the surface of the skin as well as possible.

Indeed, a flexible and light patch will have the advantage of being comfortable to wear since it is almost imperceptible.

According to one example, the substrate comprises parylene and/or polyurethane.

According to one example, the transparent electrode is made of ITO.

This allows the photoreceptor stack to better receive the light signals emitted by the first light-emitting stack and by the second light-emitting stack.

According to one example, the device comprises a wireless data transmission device.

This preferably allows the nursing staff to be kept informed of the evolution of a healing and thus, for example, to anticipate a change in treatment.

Thus, the quality of wound care during hospital or home care can advantageously be improved.

According to one embodiment, the invention comprises a medical dressing comprising a wireless data transmission device so as to be able to connect to a computer program preferably accessible on a smartphone.

This preferentially allows digitization of the data.

Indeed, to complete the oximetry analysis, it may be appropriate to collect the data within the same computer program.

It is specified that in the context of the present invention, the term “soft” or “flexible” with regard to the dressing, or else the substrate. It can be understood in a certain way, as a characteristic of the material that can deform according to the areas of the body and the directions of extension of the skin on which it is likely to be used.

In general and in the context of the present invention, the term “flexible” or “flexible” will mean the property of an element thus qualified to bend easily in order in particular to be placed on surfaces having a non-zero curvature. Thus a flexible substrate means a substrate capable of deforming elastically with a deflection greater than the thickness of the substrate.

In general and in the context of the present invention, the term “stretchable” will be understood to mean the ability of a material to deform, to elongate, to expand or to stretch in all directions in an elastic manner. or not.

The acronym "OLED" corresponds to an English term which means an organic light-emitting diode.

The acronym “OPD” corresponds to an English term which means an organic photodiode, which could be, according to one example, a semiconductor component having the capacity to capture radiation from the optical domain and to transform it into an electrical signal.

It is specified that in the context of the present invention, the terms “on” or “above” do not necessarily mean “in contact with”. Thus, for example, interlayers or intermediate members may be present.

In general, by height is meant a dimension located along the thickness of the substrate 2. The substrate 2 generally comprises two opposite faces around its thickness, one of the faces being used for the realization, of the invention .

The face being used for the realization, of the invention is advantageously flat, along a plane advantageously perpendicular to the thickness of the substrate 2.

In general, the terms "substantially", "approximately", "of the order of" mean, when they refer to a value, "within 10%" of this value or, when they refer to an angular orientation, "within 10°" of this orientation. Thus, a direction substantially normal to a plane means a direction having an angle of 90±10° relative to the plane.

A “partially transparent” element is understood to mean an element configured to at least partially transmit incident light rays, and more particularly at least 20%, or even at least 40%, or even at least 50%, or even at least 70%, of incident light rays, these light rays being in particular in the visible range.

Furthermore, a “semi-reflecting” element is understood to mean an element configured to at least partially reflect incident light rays, and more particularly at least 10%, or even at least 20%, or even at least 40%, or even at least 60% of the incident light rays, these light rays being in particular in the visible range.

The substrate can be solid or multi-layered and made of different materials such as conductive, insulating or semi-conductive materials, such as polymer or a high performance plastic for example.

The substrate may itself comprise several layers. For example, the substrate may include a dielectric surface layer above which the succession of layers of the invention is produced. The substrate may also optionally incorporate members such as active or passive electrical elements. The substrate is generally the support part used during the manufacturing steps of the device and of which at least a part is advantageously kept at the end of the manufacturing to participate in said device.

A layer based on a material A is understood to mean a layer comprising this material A and possibly other materials, for example alloying elements. A layer can also be composed of several sub-layers of the same material or of different materials; this is for example the case for the polymer-based layer. On the other hand, the term "layer" does not necessarily mean a full plate distribution on the support.

It is specified that in the context of the present invention, the thickness of a layer or of a substrate is measured in a direction perpendicular to the surface along which this layer or this substrate has its maximum extension. Therefore, in the following description, the film thicknesses are measured along directions perpendicular to the surface of the support or substrate.

The deposition of materials can be done, depending on the material, using one or other of the techniques commonly used by the microelectronics industry and which are most often referred to by the terms: PVD, CVD , PECVD and ALD, ECO, English acronyms corresponding respectively to "physical vapor deposition", "chemical vapor deposition", "Plasma-enhanced chemical vapor deposition", "atomic layer deposition", i.e. " physical vapor deposition", "chemical vapor deposition", "plasma-assisted chemical vapor deposition", "atomic layer deposition", "electrochemical deposition". The deposition can also be done by “spin coating”, that is to say by centrifugation of the material deposited in liquid or viscous form on the surface of the substrate. The thicknesses deposited are typically within a range of values going from 1 nm (nanometer, that is to say 10 −9 meters) to 350 nm.

According to the embodiment, the substrate 2 is a flexible and extensible substrate with a thickness less than 10 micron.

According to one embodiment, the substrate 2 comprises or consists of parylene and/or polyurethane.

According to one embodiment, the material that can be used to form the transparent electrodes is made of ITO, the acronym of the English term: “Indium tin oxide” which translates into indium-tin oxide or else indium oxide doped with tin.

According to one embodiment, the transparent ITO electrode is directly deposited on the face of the substrate 2 used for the production of the invention as the first layer deposited to form the photoreceptor stack 120 comprising the organic photoreceptor layer.

According to one embodiment, the transparent ITO electrode is a positive electrode of the stack, namely an anode.

According to one embodiment, for the first electroluminescent stack 110 as well as for the second electroluminescent stack 130, a first deposit and a second deposit are created simultaneously in order to form TCOs.

According to the same embodiment, the TCO is of the “AZO” type, an acronym for the English term “Aluminum-doped Zinc Oxide”.

As shown in and according to another embodiment, the TCO layer is composed of a ZnO (zinc oxide) / Ag (silver)-Ti (titanium) / ZnO (zinc oxide) or ZnO / Ag / Ti / ZnO.

According to the invention, the first layer of ZnO (Zinc Oxide) of a few tens of nm is preferentially deposited on the substrate 2 to advantageously improve the adhesion of the layer of Ag (Silver), on the flexible substrate 2.

The Ag (silver) layer of a few tens of nm is used to preferentially improve the conductivity of the TCO.

The layer of Ti (titanium) of a few nm is used to ensure better interconnection with the second layer of ZnO (Zinc Oxide) advantageously used for the injection of positive charge carriers.

According to one embodiment, the TCO layer is composed of a layer of Ag (silver) whose thickness can vary.

According to one embodiment, the thickness of the silver layer is 25 nm.

According to one embodiment, the thickness of the silver layer is 35 nm.

As shown in and according to one embodiment, the method of manufacturing an oximeter preferably allows optimized manufacturing by the simultaneous production of three stacks 10 of layers, of which the materials deposited during the steps of filling the layers are frequently the same.

According to the same embodiment, a spacing between the stacks should be noted.

In fact, for proper operation of the oximetry device and in order to avoid any short circuit, the various stacks should be spaced out.

According to one embodiment, the spacing between the stacks may be filled with at least one component, one member or at least one electrically insulating layer.

“Electrically insulating” should be considered as a property whose function is to prevent the passage of any electric current between two conductive parts subject to a difference in electric potential.

According to one embodiment, the oximeter manufacturing method advantageously allows the production of a set of three stacks 10 comprising a first light-emitting stack 110, a second light-emitting stack 130 and a photoreceptor stack 120. These stacks are juxtaposed, and preferably aligned, preferably with the OPD between the others, on one face of the support and have functions, emissive or receiving, different from each other. For example, these stacks are separated by less than 200 μm.

According to this same embodiment, these three stacks are located between a common flexible substrate 2 and a common upper electrode 3. The term “upper” means that this electrode is opposite the support.

According to one example, the photoreceptor stack 120 is located on the substrate 2, between the first electroluminescent stack 110 and the second electroluminescent stack 130.

According to one embodiment, the upper common electrode 3 is made of silver.

According to one embodiment, the common upper electrode 3 is made of aluminum.

Indeed, as illustrated in , a red OLED with a silver cathode that emits an electroluminescent emission spectrum corresponding to a resonance length of 630 nm has a greater gain in efficiency than with an aluminum cathode.

Preferably, the infrared OLED with a resonance wavelength of 850 nm has a greater gain in efficiency with an Ag cathode.

According to one embodiment, the resonance peak of a red OLED whose HTL layer is 240 nm thick in NPB: F4TCNQ is 700 nm.

According to one embodiment, the resonance peak of an infrared OLED whose HTL layer is 330 nm thick in NPB: F4TCNQ is 830 nm.

According to one embodiment, the upper common electrode 3 is composed of silver and is approximately 100 nm thick.

According to one embodiment, the upper common electrode 3 is a cathode common to the first electroluminescent stack 110, to the second electroluminescent stack 130 and to the photoreceptor stack 120.

According to one embodiment, the oximeter manufacturing process provides for a distribution by successively stacked layers according to a precise order that can be interpreted on the which will be read from bottom to top.

According to one embodiment, the manufacturing method advantageously allows the simultaneous production of different layers when the same material is included in layers taken separately from among the stacks.

According to an example, and according to the reading mode consisting in considering the lower layers as those arranged from the substrate 2 and on which the upper layers are stacked until the placement of a common electrode 3, the first electrode 111, the second electrode 131 are simultaneously deposited on the substrate 2.

In general, two steps carried out “simultaneously” are understood to mean two steps taking place at the same instant, or successively or at the immediately preceding instant or the immediately subsequent instant.

According to the same embodiment, the transparent electrode 121 is then deposited on the substrate 2.

According to one embodiment, the transparent electrode 121 is deposited upstream of the first electrode 111 and upstream of the second electrode 131.

According to one embodiment, once the first electrode 111, the second electrode 131 and the transparent electrode 121 have been deposited, the first organic hole transport layer 112, the second organic hole transport layer 132 and the third organic hole transport layer 122 are deposited simultaneously.

According to one embodiment, the first organic hole transport layer 112, the second organic hole transport layer 132 and the third organic hole transport layer 122 are 240 nm, 60 nm and 330 nm respectively.

According to one embodiment, the first organic hole transport layer 112, the second organic hole transport layer 132 and the third organic hole transport layer 122 are of the same material, preferably NPB: 5%F4TCNQ.

Preferably, the first hole transport layer 112, the second organic hole transport layer 132 and the third organic hole transport layer 122 are composed of a P-type organic host material, electrically doped with an organic dopant of type N. The doping is preferentially of type P.

As shown in and according to one embodiment, the first organic hole transport layer 112, the second organic hole transport layer 132 and the third organic hole transport layer 122 correspond respectively to the layers HTL1, HTL2 and HTL3.

The acronym HTL corresponds to the English term “Hole Transport Layer”.

According to one embodiment, the first electroluminescent stack 110 and the second electroluminescent stack 130 preferably comprise resonant microcavities.

In the specific case of resonant cavities, the resonance λ _r of the microcavity is defined by the Fabry-Pérot law which can be stated according to the equation:

The parameter m is the number of resonance modes, L _i the thickness of the i layer in the OLED microcavity, n _i the refractive index of the i layer and θ _i the angle of incidence of the i layer.

According to one embodiment of the present invention, the resonance of the microcavities varies greatly with the thickness of the organic layers.

According to one embodiment, the resonance of the microcavities is determined by varying the thickness of the first organic hole transport layer 112 and of the second organic hole transport layer 132.

Indeed, the first organic hole transport layer 112 and the second organic hole transport layer 132 are preferentially electrically doped to allow better electrical conductivity and a reduction in the voltage drop independently of the total thickness.

As illustrated on the , it is worth noting the increase in resonance as a function of the increase in the thickness of the HTL layer for wavelengths between 450 nm and 900 nm.

According to one embodiment, in order to advantageously optimize the absorption of oxygenated hemoglobins HbO2, the thickness of the second organic hole transport layer 132 must be greater than or equal to 320 nm.

According to one embodiment, and in order to advantageously optimize the absorption of non-oxygenated hemoglobins Hb, the thickness of the first organic hole transport layer 112 must be greater than or equal to 180 nm.

According to one embodiment, the photoreceptor stack 120 comprises the third hole transport layer 122 preferably in NPB: 5%F4TCNQ and preferably with a thickness of about 60 nm, the production of which is carried out in a step simultaneous or immediately preceding or subsequent to the step of producing at least one step from producing the first organic hole transport layer 112 and producing the second organic hole transport layer 132.

According to one embodiment, the first electroluminescent stack 110 comprises a first active organic layer 113 located above the first organic hole transport layer 112.

According to one embodiment, the second electroluminescent stack 130 comprises a second active organic layer 133 located above the second organic hole transport layer 132.

According to one embodiment, the first active organic layer 113 and the second active organic layer 133 are preferentially of the same thickness, preferably 20 nm.

According to one embodiment, the photoreceptor stack 120 comprises a photoreceptor layer 123 located above the third organic hole transport layer 122.

As shown in and according to one embodiment, the first active organic layer 113, the second active organic layer 133 and the photo-receptive organic layer 123 correspond respectively to the EML1, EML2 and EML3 layers.

According to one embodiment, the thickness of the first active organic layer 113 is around 20 nm.

According to one embodiment, the thickness of the second active organic layer 133 is around 20 nm.

According to one embodiment, the thickness of the organic photoreceptor layer 123 is approximately 20 nm.

According to one embodiment, the first active organic layer 113 is composed of CBP: Ir complex. Advantageously, the first active organic layer 113 comprises a host organic material doped with a fluorescent or phosphorescent organic material emitting for example a red luminance.

According to one example, the first electroluminescent stack 110 emits light waves whose wavelengths are greater than 600 nm and/or less than 750 nm.

According to one embodiment, the second active organic layer 133 is composed of CBP: Ir complex. Advantageously, the second active organic layer 133 comprises a host organic material, doped with a fluorescent or phosphorescent organic material emitting a near infrared luminance. .

According to one example, the second electroluminescent stack 130 emits light waves whose wavelengths are greater than 820 nm and/or less than 1000 nm.

According to one embodiment, the organic photoreceptor layer 123 is composed of P3HT:PCBM. Advantageously, the photo-receptive organic layer 123 comprises a mixture composed of a P-type organic material and an N-type organic material.

According to one embodiment, the first electroluminescent stack 110 comprises the first active organic layer 113, the second electroluminescent stack 130 comprises the second active organic layer 133 so that the step of producing the first active organic layer 113 s carried out in a step that is simultaneous or immediately preceding or subsequent to the step of producing the second active organic layer 133.

According to one embodiment, the photoreceptor stack 120 comprises the organic receptor layer 123 preferably composed preferably of P3HT:PCBM and preferably with a thickness of about 20 nm, the production of which is carried out in a simultaneous step or immediately preceding or subsequent to the step of producing at least one step from producing the first active organic layer 113 and producing the second active organic layer 133.

According to one embodiment, the first electroluminescent stack 110 comprises a first electron transport layer 114 located above the first active organic layer 113.

According to one embodiment, the second electroluminescent stack 130 comprises a second electron transport layer 134 located above the second active organic layer 133.

According to one embodiment, the photoreceptor stack 120 comprises a third organic electron transport layer 124 located above the organic photoreceptor layer 123.

As shown in and according to one embodiment, the first organic electron transport layer 114, the second organic electron transport layer 134 and the third organic electron transport layer 124 correspond respectively to the layers ETL1, ETL2 and ETL3.

According to one embodiment, the thickness of the first organic electron transport layer 114 is approximately 60 nm.

According to one embodiment, the thickness of the second organic electron transport layer 134 is approximately 60 nm.

According to one embodiment, the thickness of the third organic electron transport layer 124 is approximately 60 nm.

According to one embodiment, the first organic electron transport layer 114 and the second organic electron transport layer 134 and the third organic electron transport layer 124 have the same deposition thickness of approximately 60 nm.

According to one embodiment, the first organic electron transport layer 114 and the second organic electron transport layer 134 and the third organic electron transport layer 124 are composed of the same material ALq3.

According to one embodiment, the first electroluminescent stack 110 comprises the first organic electron transport layer 114, the second electroluminescent stack 130 comprises the second organic electron transport layer 134 and the photoreceptor stack 120 comprises the third organic layer electron transport layer 124. The three layers raised are configured so that the step of producing one of the layers among the first organic electron transport layer 114, the second organic electron transport layer electrons 134 and the third organic electron transport layer 124. is carried out in a step that is simultaneous or immediately preceding or immediately subsequent to the step of producing the two other layers among the first organic electron transport layer 114, the second organic electron transport layer 134 and the third organic electron transport layer 124.

According to one embodiment, a buffer layer 51 is positioned between at least the set of three stacks 10 and the common upper electrode 3, it is preferably a LiF layer with a thickness of 1 nm advantageously allowing promote charge injection by tunnel effect.

According to one embodiment, the first electroluminescent stack 110 comprises a buffer layer 51 located above the first organic electron transport layer 114.

According to one embodiment, the second electroluminescent stack 130 comprises a buffer layer 51 located above the second organic electron transport layer 134. According to one embodiment, the photoreceptor stack 120 comprises a buffer layer 51 located at the above the third organic electron transport layer 124.

According to one embodiment, the first electroluminescent stack 110 comprises a buffer layer 51, the second electroluminescent stack 130 comprises a buffer layer 51 and the photoreceptor stack 120 comprises a buffer layer 51. The three layers raised are configured so that the step of producing one of the layers from among the three layers is carried out in a step that is simultaneous or immediately preceding or subsequent to the step of producing the two other layers from among the three layers mentioned above.

According to one embodiment, the common upper electrode 3 is located above all three stacks, namely preferably above buffer layers 51 or above layers ETL1, ETL2 and ETL3.

According to one example, the electrical connectors are printed by inkjet in order to advantageously optimize the thickness of the device and to respond to the problem of lowering manufacturing costs. Furthermore, it should be noted that the printing of electrical connectors by inkjet is a technology particularly suitable for flexible and flexible devices such as for example for according to certain embodiment of the present invention.

According to a particular embodiment, a medical dressing comprising a wireless data transmission device is configured so as to be able to connect to a computer program preferably accessible on a smartphone in order to preferentially allow data to be digitized and thus keep the patient informed. caregivers of the evolution of healing in order to anticipate a change in treatment and thus improve the quality of wound care during care in hospitals or at home.

According to this same embodiment, the oximetry device is directly integrated into a medical dressing or a medical patch and advantageously provides comfort due to the flexibility and lightness of the assembly.

According to a particular embodiment, an additional encapsulation layer advantageously covers the common upper electrode 3.

According to a particular embodiment, an additional encapsulation layer closes the interstitial spaces left vacant between the different stacks.

In addition, to complete the oximetry analysis, it may be appropriate to collect the data within the same computer program.

The invention is not limited to the embodiments described above and extends to all the embodiments covered by the claims.

List of references
2. substrate
3. common upper electrode
10. set of three stacks
41. first microcavity
42. second microcavity
51. buffer layer
110. first electroluminescent stack
111. first electrode
112. first organic hole transport layer
113. first active organic layer
114. first organic electron transport layer
120. photoreceptor stacking
121. transparent electrode
122. third organic hole transport layer
123. photo-receptive organic layer
124. third organic electron transport layer
130. second light emitting stack
131. second electrode
132. second organic hole transport layer
133. second active organic layer
134. second organic electron transport layer

Claims (20)

Method of manufacturing an oximeter comprising a flexible and extensible substrate (2) and a common upper electrode (3) and, located between the substrate (2) and the common upper electrode (3), a set of stacks (10 ) distinct formed by:

• a first electroluminescent stack (110) in which are produced successively:
  • a first electrode (111);
  • a first organic hole transport layer (112);
  • a first active organic layer (113);
  • a first organic electron transport layer (114);
• a second electroluminescent stack (130) in which are carried out successively:
  • a second electrode (131);
  • a second organic hole transport layer (132);
  • a second active organic layer (133);
  • a second organic electron transport layer (134);
• a photoreceptor stack (120) where successively:
  • a transparent electrode (121);
  • a third organic hole transport layer (122);
  • an organic photo-receptive layer (123);
  • a third organic electron transport layer (124);

the set of three stacks (10) being formed between the common substrate (2) and the common upper electrode (3),
characterized in that:

• the first hole transport layer (112), the second organic hole transport layer (132) and the third organic hole transport layer (122) are made of the same material,

• the first organic electron transport layer (114), the second organic electron transport layer (134) and the third organic electron transport layer (124) are made of the same material,
• the first electrode (111) and the second electrode (131) are made of semi-reflecting materials so as to form between each of them and the common upper electrode, respectively a first microcavity (41) and at least one second microcavity (42).

Method of manufacturing an oximeter according to the preceding claim, in which the set of three stacks is made such that the sum of the thickness of the first organic layer for transporting holes (112) with the thickness of the first layer organic electron transport layer (114) is strictly less than the sum of the thicknesses of the second organic hole transport layer (132) and of the second organic electron transport layer (134), so that the first microcavity (41) has a first resonance peak different from a second resonance peak of the second microcavity (42). Method of manufacturing an oximeter according to any one of the two preceding claims, in which the set of three stacks is produced such that the thickness of the first organic layer for transporting holes (112) is equal to the thickness of the second organic hole transport layer (132) and the thickness of the first organic electron transport layer (114) is greater than the thickness of the second organic electron transport layer (134), so that the first microcavity (41) has a first resonance peak different from a second resonance peak of the second microcavity (42). Method of manufacturing an oximeter according to either of Claims 1 and 2, in which the set of the three stacks is produced such that the thickness of the first organic layer for transporting holes (112) is less than 1 thickness of the second organic hole transport layer (132) and the thickness of the first organic electron transport layer (114) is equal to the thickness of the second organic electron transport layer (134) , so that the first microcavity (41) has a first resonance peak different from a second resonance peak of the second microcavity (42). Method of manufacturing an oximeter according to any one of the preceding claims, in which the set of three stacks is made so that:

• either the thickness of the first organic hole transport layer (112) is equal to the thickness of the second organic hole transport layer (132) and is equal to the thickness of the third organic hole transport layer (122).
• either the thickness of the first organic electron transport layer (114) is equal to the thickness of the second organic electron transport layer (134) and is equal to the thickness of the third organic transport layer of electrons (124).

Method of manufacturing an oximeter according to any one of the preceding claims, in which the first electroluminescent stack (110) is produced in such a way as to emit light waves whose wavelengths are greater than 600 nm and/or less than 750 nm. n. Method of manufacturing an oximeter according to any one of the preceding claims, in which the second electroluminescent stack (130) is configured to emit light waves whose wavelengths are greater than 820 nm and/or less than 1000 nm. A method of manufacturing an oximeter according to any preceding claim, comprising forming electrical connectors printed by ink jet. Oximeter comprising a flexible and extensible substrate (2), and a common upper electrode (3) and, located between the substrate (2) and the common upper electrode (3), a set of three separate stacks (10) comprising:

• a first electroluminescent stack (110) successively comprising:
  • a first electrode (111);
  • a first organic hole transport layer (112);
  • a first active organic layer (113);
  • a first organic electron transport layer (114);
• a second electroluminescent stack (130) successively comprising:
  • a second electrode (131);
  • a second organic hole transport layer (132);
  • a second active organic layer (133);
  • a second organic electron transport layer (134);
• a photoreceptor stack (120) successively comprising:
  • a transparent electrode (121);
  • a third organic hole transport layer (122);
  • an organic photo-receptive layer (123);
  • a third organic electron transport layer (124);

the set of three stacks (10) being ordered between the common substrate (2) and the common upper electrode (3),
characterized in that:

• the first hole transport layer (112), the second organic hole transport layer (132) and the third organic hole transport layer (122) are composed of the same material,

• the first organic electron transport layer (114), the second organic electron transport layer (134) and the third organic electron transport layer (124) are composed of the same material,
• the first electrode (111) and the second electrode (131) are semi-reflecting so as to form between each of them and the common upper electrode, respectively a first microcavity (41) and at least one second microcavity (42).

Oximeter according to the preceding claim, in which the set of three stacks is configured so that the sum of the thickness of the first organic hole transport layer (112) with the thickness of the first organic electron transport layer (114) is strictly less than the sum of the thicknesses of the second organic hole transport layer (132) and of the second organic electron transport layer (134), so that the first microcavity (41) has a first resonance peak different from a second resonance peak of the second microcavity (42). Oximeter according to any one of the two preceding claims, in which the set of three stacks is configured such that the thickness of the first organic hole-transporting layer (112) is equal to the thickness of the second organic layer of hole transport (132) and the thickness of the first organic electron transport layer (114) is greater than the second organic electron transport layer (134), so that the first microcavity (41) has a first resonance peak different from a second resonance peak of the second microcavity (42). Oximeter according to either of Claims 9 and 10, in which the set of three stacks is configured such that the thickness of the first organic layer for transporting holes (112) is less than the thickness of the second organic layer transport hole (132) and the thickness of the first organic electron transport layer (114) is equal to the second organic electron transport layer (134), so that the first microcavity (41 ) has a first resonance peak different from a second resonance peak of the second microcavity (42). Oximeter according to any one of Claims 9 to 12, in which the first electrode (111) and/or the second electrode (131) comprise a sequence of layers in the following order ZnO; Ag; Ti; ZnO. Oximeter according to any one of Claims 9 to 13, in which the thickness of the first organic hole-transporting layer (112) is greater than 220 nm and/or less than 260 nm, the thickness of the second organic layer of hole transport (132) is greater than 300 nm and/or less than 360 nm, the thickness of the third organic hole transport layer (122) is greater than 54 nm and/or less than 66 nm. Oximeter according to any one of Claims 9 to 14, comprising at least two sets of three distinct stacks (10). Oximeter according to any one of Claims 9 to 15, in which the common upper electrode (3) is made of silver. Oximeter according to any one of Claims 9 to 16, in which the first active organic layer (113), the second active organic layer (133) and the organic photoreceptor layer (123) are of the same thickness. An oximeter according to any of claims 9 to 17 wherein a buffer layer (51) is positioned between at least the set of three stacks (10) and the common upper electrode (3). Oximeter according to any one of Claims 9 to 18, in which the substrate (2) consists of a transparent material, preferably parylene and/or polyurethane, having a property allowing it to be flexible and stretchable in order to be able to adapt to skin surfaces. A medical dressing comprising an organic oximeter according to any one of claims 9 to 19 together with an adhesive surface.