Optoelectronic device for luminous display with conductive light-containing walls and manufacturing process

Abstract

An optoelectronic device (10) for a light display, comprising: a support (11); a plurality of light elements (13) electrically connected to at least one first electrode (13d) and comprising a light-emitting diode (15) a doped portion of which is arranged in electrical contact with said first electrode (13d), said first electrode (13d) covering at least an upper portion of said doped portion arranged on the side opposite the support face (11a); a plurality of light-containing walls (16) configured to reflect all or part of the light emitted by at least one of the light elements (13) and arranged to surround all or part of said at least one of the light elements (13); the light-containing walls (16) of the plurality of light-containing walls (16) being electrically conductive and directly connected to the first electrode (13d). Figure 2

Description

Title of the invention: Optoelectronic device for luminous display with conductive light-containing walls and manufacturing method technical field

[0001] The present invention relates to an optoelectronic device for light display, comprising:

[0002] a support delimiting a support face,

[0003] a plurality of luminous elements fixed to the support face, each luminous element being electrically connected to at least one first electrode and comprising at least one light-emitting diode having an active part capable of emitting light when a current passes through the active part and at least one doped part arranged in a position of electrical contact with said at least one first electrode,

[0004] a plurality of light containment walls, each light containment wall being configured so as to have an ability to reflect all or part of the light emitted by at least one of the light elements and being arranged so as to surround all or part of said at least one of the light elements so as to reflect all or part of the light emitted by said at least one light element.

[0005] The invention also relates to a method of manufacturing an optoelectronic device for light display. STATE OF PRIOR ART

[0006] In the field of luminous display screens, the luminous elements constituting the screen must be arranged in a matrix. The precision required to form such a matrix increases as the expected resolution of the screens increases.

[0007] It is known to produce the light-emitting diodes that constitute the luminous elements on a first substrate, for example a silicon or sapphire wafer, and to transfer them onto a second substrate intended to form an integral part of the screen. The electrical connections that allow the light-emitting diodes thus transferred to be powered are made at the level of the second substrate.

[0008] In the case where the light-emitting diodes are separated by a distance of less than ten microns, the electrical connection of the upper part of the light-emitting diodes and the electrical connection of their lower part remain difficult to achieve without risk of unintentional short circuit, due to the small distance which separates them.

[0009] In the case of three-dimensional light-emitting diodes, typically wire-shaped, which is a very advantageous form, obtaining an electrical connection at their upper end is difficult due to their micrometric or even nanometric dimensions. An additional problem encountered during the transfer of the light-emitting elements is that the precise positioning of the light-emitting elements on the second support is not guaranteed because of the increasingly small dimensions of the light-emitting elements and electrical connections required to achieve the best possible resolution for the light display offered by the optoelectronic device. The usual techniques for re-establishing electrical contacts on the light-emitting elements are unsatisfactory because the positioning errors are random and within an error range that is too large relative to the dimensions of the light-emitting elements and electrical connections. Description of the invention

[0010] The present invention aims to provide an optoelectronic device and a manufacturing process that addresses all or part of the problems presented above.

[0011] In particular, one aim is to provide a solution that meets at least one of the following objectives:

[0012] - to enable the provision of an optoelectronic device for light display limiting the risks of short circuits;

[0013] - to enable the provision of an optoelectronic device for luminous display to lower cost;

[0014] - to enable the provision of an optoelectronic device for luminous display having large dimensions;

[0015] - to enable the provision of an optoelectronic device for luminous display having high performance and the highest possible display resolution;

[0016] - to enable the supply of an optoelectronic device, the majority of which The light elements are electrically connected in a satisfactory manner.

[0017] This goal can be achieved by means of an optoelectronic device for luminous display, comprising: -a support delimiting a support face; -a plurality of luminous elements fixed to the support face, each luminous element being electrically connected to at least one first electrode and comprising at least one light-emitting diode having an active part capable of emitting light when a current passes through the active part and at least one doped part arranged in electrical contact with said at least one first electrode, said first electrode covering at least an upper part of said doped part arranged on the side opposite the support face; -a plurality of light containment walls, each light containment wall being configured so as to have an ability to reflect all or part of the light emitted by at least one of the light elements and being arranged so as to surround all or part of said at least one of the light elements so as to reflect all or part of the light emitted by said at least one light element; all or part of at least one of the light containment walls of the plurality of light containment walls having the ability to be electrically conductive and connected directly to the first electrode of at least one of the light elements of said plurality of light elements.

[0018] Some preferred but not limiting aspects of the device are the following.

[0019] In an implementation of the device, at least one of the luminous elements of the plurality of luminous elements comprises all or part of a control device configured to modulate at least one emission parameter associated with said at least one light-emitting diode comprising said luminous element.

[0020] In one implementation of the device, the control device of at least one of the light elements is electrically connected to a second electrode electrically isolated from the first electrode, said second electrode being electrically connected to at least one other light containment wall among the plurality of light containment walls, where said other light containment wall is electrically isolated from the light containment wall in electrical contact with the first electrode of said light element.

[0021] In one embodiment of the device, at least one of the light-emitting diodes of at least one of the light elements has a three-dimensional wire shape extending along a principal axis oriented transversely to the support face, the first electrode surrounding at least an upper portion of said light-emitting diode arranged on the side opposite the support face along the principal axis.

[0022] In one embodiment of the device, the first electrode is arranged at the level of a lower portion of the light-emitting diode located on a side opposite to the upper portion along the main axis.

[0023] In one embodiment of the device, the first electrode is formed in an electrically conductive material and at least partially transparent to the light emitted by the active part of the light-emitting diode in contact with said first electrode.

[0024] In one embodiment of the device, all or part of the first electrode is covered, on a side opposite the support, by a portion of spacing formed on the first electrode, the light confinement walls being formed through said portion of spacing to be in contact with the first electrode.

[0025] In one embodiment of the device, a first electrical conductor is formed on an upper face of the spacer portion arranged on one side opposite the support face along the main axis so that the first electrical conductor is in electrical contact with at least one of the light containment walls.

[0026] In an implementation of the device, said spacing portion is formed by a passivation layer at least partly transparent to the light emitted by the light element around which it is arranged and electrically insulating and / or by a light conversion layer capable of converting at least a first wavelength of the light emitted by the light element, around which it is arranged, into a second wavelength different from the first wavelength.

[0027] In one embodiment of the device, at least one of the light containment walls comprises an electrical conduction layer characterized by an electrical conductivity greater than 106 Siemens / m.

[0028] In one embodiment of the device, the electrical conduction layer is formed by at least one element belonging to the group comprising silver, aluminum, a copper-silver alloy, gold, a silver-gold alloy, a gold-aluminum alloy, a tungsten-silver alloy, a tungsten-aluminum alloy.

[0029] In one embodiment of the device, the support is formed in a material other than a crystalline material.

[0030] In an implementation of the device, at least two light containment walls belonging to the plurality of light containment walls are electrically connected to each other.

[0031] In one implementation of the device, the luminous elements are obtained on an external support different from the support prior to a transfer of said luminous elements to the support.

[0032] In one embodiment of the device, the device includes an electrical insulation layer arranged between at least a portion of the support face and all or part of the first electrode.

[0033] The invention also relates to the implementation of a method for manufacturing an optoelectronic device for light display, the manufacturing method comprising the following steps: a) provision of a support delimiting a support face; b) formation of at least one first electrode covering at least an upper part of said doped part arranged on the side opposite the support face; (c) formation of a plurality of luminous elements fixed to the support face, during which said at least one first electrode is electrically connected to at least one of the luminous elements formed and in which each luminous element is electrically connected to said at least one first electrode and comprising at least one light-emitting diode having an active part capable of emitting light when a current passes through the active part and at least one doped part arranged to be in a situation of electrical contact with said at least one first electrode; d) formation of a plurality of light containment walls wherein each light containment wall formed has the ability to reflect all or part of the light emitted by at least one of the light elements and is arranged so as to surround all or part of said at least one of the light elements so as to reflect all or part of the light emitted by said at least one light element, step d) being such that all or part of at least one of the light containment walls of the plurality of light containment walls has the ability to be electrically conductive and directly connected to the first electrode of at least one of the light elements of said plurality of light elements.

[0034] Some preferred but not limiting aspects of the process are the following.

[0035] In one implementation of the manufacturing process, the process includes the step next, implementation between step b) and step d): e) formation of a spacing portion on said at least a first electrode formed in step b) on a side opposite the support; the light confinement walls being formed during step d) through the spacing portion formed in step e) and to be in contact with the first electrode formed in step b).

[0036] In one implementation of the manufacturing process, step d) includes at least one etching step in which the portion of spacing obtained in step e) undergoes controlled etching so as to stop said etching when the first electrode is flush.

[0037] In one implementation of the manufacturing process, the process includes the following step: f) formation of an electrical conductivity layer in the etching resulting from step d); step f) being carried out so that the electrical conductivity layer formed is in electrical contact with the first electrode formed in step b) and is characterized by an electrical conductivity greater than 106 Siemens / m; all or part of step f) being carried out during step d).

[0038] In one implementation of the manufacturing process, step d) includes a filling step consisting of filling all or part of the engraving resulting from step d) with an electrically conductive material.

[0039] In one implementation of the manufacturing process, step c) includes a remote manufacturing step of the luminous elements in which the luminous elements are obtained on an external support different from the support and then transferred so as to be fixed on the support face of the support. Brief description of the drawings

[0040] Other aspects, objectives, advantages and features of the invention will become clearer upon reading the following detailed description of preferred embodiments thereof, given by way of non-limiting example, and made with reference to the accompanying drawings in which:

[0041] [Fig-1] is a schematic cross-sectional view of an example of an optoelectronic device tronics according to the invention;

[0042] [Fig.2] is a schematic cross-sectional view of an example of an optoelectronic device tronic according to the invention in which the light confinement walls comprise a conduction layer;

[0043] [Fig.3] is a schematic cross-sectional view of an example of an optoelectronic device electronics according to the invention in which the light elements comprise a control device;

[0044] [Fig.4] is a schematic cross-sectional view of an example of an optoelectronic device tronic according to the invention in which a first upper conductor is electrically connected to the light confinement walls;

[0045] [Fig. 5] is a schematic cross-sectional view of an example of an optoelectronic device tronic according to the invention in which one of the luminous elements is electrically connected to a second electrode and to a luminous confinement wall;

[0046] [Fig.6] is a schematic cross-sectional view of an example of an optoelectronic device electronics according to the invention in which a luminous element comprises several light-emitting diodes and a control device;

[0047] [Fig.7] is a schematic cross-sectional view of several stages of an example of manufacturing process according to the invention;

[0048] [Fig.8] is a schematic cross-sectional view of several steps of a supplementary example commentary on the manufacturing process according to the invention implementing a portion of spacing;

[0049] [Fig.9] is a schematic cross-sectional view of several steps of a supplementary example commentary on the manufacturing process according to the invention implementing an electrical conductivity layer;

[0050] [Fig. 10] is a schematic cross-sectional view of a further example of a optoelectronic device according to the invention in which a protective layer is arranged on a portion of spacing, the protective layer having openings leading to the light confinement walls.

[0051] DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

[0052] In the attached figures 1 to 10 and in the rest of the description, elements Identical or functionally similar components are identified by the same reference numerals. Furthermore, the various elements are not drawn to scale to ensure clarity in the figures and facilitate understanding. Moreover, the different embodiments and variants are not mutually exclusive and can, on the contrary, be combined.

[0053] In the rest of the description, unless otherwise indicated, the terms "approximately", "about", "overall" and "in the order of" mean "within 10%".

[0054] For clarity, identical or similar elements have been designated by the same reference numbers in the various drawings and, moreover, as is customary in the representation of electronic circuits, the various drawings are not to scale. Furthermore, only the elements that are useful for understanding this description have been shown and will be described. In particular, the means for contacting the optoelectronic device, substrate, biasing, and control are well known and will not be described.

[0055] The invention relates primarily to an optoelectronic device for displaying light. An optoelectronic device is understood to be a device capable of producing light based on an electrical or electronic control. A display of light is understood to mean the display of luminous pixels or the display of illumination or backlighting. This display of light can be implemented for screens such as television screens, virtual or augmented reality headsets, or screens for mobile devices. The display of light can be monochrome or polychrome.

[0056] As illustrated in Figures 1 to 6, the optoelectronic device 10 for a light display comprises, on the one hand, a support 11 defining a support face 1a. The support 11 is, for example, a semiconductor substrate such as silicon, germanium, sapphire, or a type II, III, V, or VI semiconductor material. The support 11 is, for example, electrically insulating and formed by one or more glass plates. The support 11 may also be electrically conductive and formed by one or more metal plates. The support 11 may also include insulated conductive tracks formed on its surface or within it. The support 11 may be crystalline or non-crystalline and may also include active or passive components such as transistors or memory chips. Since these latter components are common to those skilled in the art, they are not shown.Support 11 can, for example, be used as a support for a backlit display screen.

[0057] The optoelectronic device 10 also includes a plurality of luminous elements 13 fixed to the support face 1a. By fixed it is understood to mean "fixed directly or indirectly in an electrically isolated manner or in such a way as to be electrically connected to an element of the support 11".

[0058] The light elements 13 can be fixed to the support face lia by means of a fixing element, not shown, such as conductive or non-conductive adhesive. In another example, the fixing element comprises a set of metallic particles embedded in an insulating material.

[0059] In one example, the fixing element is at least partly transparent to the light emitted by the light-emitting part of the luminous elements 13.

[0060] For example, to produce a display screen, it is also possible to provide that the plurality of luminous elements 13 are arranged for example in a matrix arranged more or less regularly.

[0061] In one example, the luminous elements 13 are obtained on an external support different from the support 11 prior to a transfer of said luminous elements 13 to the support 11. This makes it possible to obtain luminous elements on a support which would be incompatible with their method of obtaining and / or on a large surface support.

[0062] Each light element 13 is electrically connected to at least one first electrode 13d.

[0063] The first electrode 13d covers at least an upper part of said doped part arranged on the side opposite the support face lia.

[0064] The first electrode 13d is formed in an electrically conductive material and at least partially transparent to the light emitted by the active part of the light-emitting diode 15 in contact with said first electrode 13d.

[0065] The first electrode 13d can be, for example, doped tin oxide, doped zinc oxide, or a matrix containing carbon nanotubes or graphene.

[0066] An electrical insulation layer 17 can also be arranged between at least part of the support face 11 and all or part of the first electrode 13d. This allows the first electrode 13d to be electrically isolated from a second electrode 13c or from the substrate. This electrical insulation layer 17 can be present before the formation of the light-emitting diodes 15 and simultaneously serve as a growth mask.

[0067] Each light element 13 comprises at least one light-emitting diode 15 having an active part capable of emitting light when a current passes through the active part.

[0068] A luminous element 13 may simply consist of a single light-emitting diode 15.

[0069] The light-emitting diodes 15 comprise at least one doped semiconductor part arranged in electrical contact with, on one side, said at least one first electrode 13d and on the other side with the active part of the same light-emitting diode.

[0070] The electrical contact between the first electrode 13d and the doped part of the light-emitting diode can be direct or indirect via one or more layers or via a control device 13b arranged in the light element 13.

[0071] In one example, this control device 13b is configured to modulate at least one emission parameter associated with at least one of the light-emitting diodes 15 comprising the light element 13. By emission parameter, we mean, for example, the intensity. This can be varied gradually between zero – zero current, zero light emission – and a maximum intensity – maximum light emission.

[0072] The control device may include transistors, memories or any component necessary for a person skilled in the art to carry out a programmable control.

[0073] The control device 13b can be connected to one -[Fig.3] or 5- or several -[Fig.6]- light-emitting diodes 15.

[0074] As illustrated in [Fig.5], the control device 13b can also be electrically connected to a second electrode 13c. This is electrically isolated from the first electrode 13d.

[0075] In examples where the light elements 13 do not include a control device 13b, the light elements 13 or the light-emitting diode(s) 15 components may be connected to the second electrode 13c.

[0076] The doping of the doped part of the light-emitting diode 15, arranged in electrical contact with the first electrode 13d, can be chosen according to a first type of doping, chosen between a P type and an N type of doping.

[0077] The contact between the doped part and the active semiconductor part can be electrical and / or physical.

[0078] In one example, at least two light-emitting diodes 15 are arranged in a light element 13. This allows for greater robustness against wear of the light elements 13. Another advantage is that the luminous power is increased.

[0079] In one example, the light-emitting diodes 15 have a three-dimensional shape in the form of microwires or nanowires. However, other examples can be implemented for three-dimensional light-emitting diodes other than microwires or nanowires, for example, conical or pyramidal three-dimensional light-emitting diodes. Light-emitting diodes with a three-dimensional shape have an elongated shape along the preferred direction called the longitudinal direction. A second dimension, called the small dimension of the light-emitting diode, extends transversely to the longitudinal direction and represents a diameter of the light-emitting diode. The dimension along the longitudinal direction The longitudinal dimension is in the range of 5 nm to 5 pm, preferably from 50 nm to 2.5 pm, and is greater than or equal to 1 time, preferably greater than or equal to 5 times, and more preferably greater than or equal to 10 times the largest small dimension. In some embodiments, the small dimensions may be less than or equal to about 1 pm, preferably in the range of 70 nm to 1 pm, more preferably in the range of 100 nm to 800 nm. In some examples, the height of each three-dimensional LED along the longitudinal dimension D may be greater than or equal to 500 nm, preferably in the range of 1 pm to 50 pm.

[0080] The light-emitting diodes 15 may also include a second part doped according to a second type of doping, chosen between a P-type and an N-type doping and opposite to the first type of doping. The second semiconductor part may be connected to the support 11 or to an electrode different from the first electrode 13d in contact with the doped part.

[0081] The term "connected" is understood, in equivalent terms, to mean "electrically connected" or "connected in an isolated manner by physical contact" and / or "connected directly or indirectly." The doped parts are formed, for example, partially from at least one semiconductor material such as silicon, germanium, silicon carbide, a IILV compound such as IILN compounds, an ILVI compound, or a combination of these compounds. Examples of Group III elements include gallium (Ga), indium (In), or aluminum (Al). Examples of IILN compounds are GaN, AN, InN, InGaN, AlGaN, or AlInGaN. Other Group V elements may also be used, for example, phosphorus or arsenic. Generally, the elements in the IILV compound may be combined in different mole fractions.Examples of Group II elements include elements from Group IIA, particularly beryllium (Be) and magnesium (Mg), and elements from Group IIB, particularly zinc (Zn) and cadmium (Cd). Examples of Group VI elements include elements from Group VIA, particularly oxygen (O) and tellurium (Te). Examples of ILVI compounds are ZnO, ZnMgO, CdZnO, or CdZn-MgO. Generally, the elements in an ILVI compound can be combined in different mole fractions. For example, for IILV compounds, the dopant may be chosen from the group comprising a Group II P-type dopant, for example, magnesium (Mg), zinc (Zn), cadmium (Cd) or mercury (Hg), a Group IV P-type dopant, for example, carbon (C) and a Group IV N-type dopant, for example, silicon (Si), germanium (Ge), selenium (Se), sulfur (S), terbium (Tb) or tin (Sn).

[0082] According to one example, the active part may include means for confining electric charge carriers such as a quantum well and / or barriers quantum. In one example, the active part can essentially be made, at the end of its formation, from a II-VI compound or a III-V compound but preferably from a III-V alloy and more particularly made from an InwGa(lw)N alloy, where w is less than or equal to 1.

[0083] The active part of the light-emitting diodes 15 emits light when a current passes through it. This light has a color that varies depending on the composition of the active layer.

[0084] In order to achieve a multicolour display, it is possible to form light-emitting diodes each directly emitting a different colour.

[0085] It is also possible to form light-emitting diodes 15 all emitting the same wavelength (generally in the blue or ultraviolet range) and to surround them at least partially with light converters. The light converters are, for example, embedded in an organic or inorganic matrix. The light converters are, for example, selected from photoluminescent pads or quantum pads. The photoluminescent pads are designed to absorb and convert at least a portion of the incident light rays emanating from the light-emitting diode 15 surrounded by the light converters. The photoluminescent pads then emit outgoing light rays of a different color, for example, green or red. These photoluminescent pads can advantageously form a wavelength filter because they prevent parasitic wavelengths from being emitted outside the optoelectronic device 10.

[0086] In an example illustrated in Figures 1 to 6, the light elements 13 are each formed by a light-emitting diode 15, which has a three-dimensional wire-like shape extending along a principal axis 18 oriented transversely to the support face lia. In this example, the first electrode 13d surrounds at least an upper portion 15a of said light-emitting diode 15 arranged on the side opposite the support face lia along the principal axis 18.

[0087] In a further example not shown, the first electrode 13d is arranged at the level of a lower portion of the light-emitting diode 15 located on a side opposite to the upper portion 15a along the main axis 18.

[0088] The optoelectronic device 10 also comprises a plurality of light-containing walls 16. Each light-containing wall 16 is configured to reflect all or part of the light emitted by at least one of the light elements 13. Each light-containing wall 16 is also arranged to surround all or part of said at least one of the light elements 13. Thus, all or part of the light emitted by said at least one light element 13 is reflected along one or more preferred directions, or omnidirectionally. In Figures 1 to 6, each light element 13 is surrounded by luminous containment walls 16 are arranged generally parallel to the main axis 18 of the luminous elements. This is advantageous for improving the integration density and increasing the reflection of light from the luminous elements 13.

[0089] In another example not shown, the number of light elements 13 formed between two light-containing walls 16 can be two or more. This increases the long-term robustness of the optoelectronic device 10.

[0090] Advantageously, all or part of at least one of the light-containing walls 16 of the plurality of light-containing walls 16 has the capacity to be electrically conductive. It is directly connected to the first electrode 13d of at least one of the light elements 13.

[0091] One advantage of this architecture is the simplification of the architecture, a reduction in the risk of false contacts and a decrease in production costs.

[0092] This is advantageous because the resumption of electrical contact on the front face (i.e. the face of the optoelectronic device offset from the support 11), to connect the light element 13, is thus facilitated.

[0093] The light containment walls 16 arranged and formed in this way therefore allow both to confine, deflect or reflect the light from the light-emitting diodes but also allow to make a contact re-establishment on the front face.

[0094] In an example illustrated in [Fig.2], at least one of the light containment walls 16 comprises an electrical conduction layer 16a characterized by an electrical conductivity greater than 106 Siemens / m.

[0095] This electrical conduction layer 16a advantageously forms a low resistance ohmic electrical contact with the doped part of at least one of the luminous elements 13.

[0096] In one example, the electrical conduction layer 16a is formed by at least one element belonging to the group comprising silver, aluminum, a copper-silver alloy, gold, a silver-gold alloy, a gold-aluminum alloy, a tungsten-silver alloy, a tungsten-aluminum alloy.

[0097] In an example illustrated in [Fig. 4], at least two light-containing walls 16 belonging to the plurality of light-containing walls 16 are electrically connected to each other. This can be achieved by a conductive layer 14 made of metal or transparent conductive oxide, for example.

[0098] In an example of an embodiment illustrated in [Fig. 5], the control device 13b of at least one of the light elements 13 is electrically connected to the second electrode 13c, which itself is electrically connected to at least one light containment wall 16. The light containment wall 16 in question is electrically isolated from another light containment wall 16 which would be connected to the first electrode 13d in contact with the same light element. This architecture is advantageous because the contact points are then only re-established on the front face.

[0099] In the example illustrated in [Fig. 5], two light-containing walls 16 surrounding a light element 13 are electrically connected to each other and to the first electrode 13d of this same light element 13. The second electrode 13c of this same light element 13 is connected to a third light-containing wall 16. A conductive layer 14a, of the same nature as the conductive layer 14 and electrically insulated from it, can be considered for the re-establishment of contact on the front face from the third light-containing wall 16. This architecture is advantageous for re-establishing all contacts on the front face.

[0100] In an example of an embodiment illustrated in Figures 1 to 6, all or part of the first electrode 13d is covered, on a side opposite the support 11, by a portion of spacing 19. In this example, the light confinement walls 16 are formed through said portion of spacing 19 to be in electrical or physical contact with the first electrode 13d.

[0101] The spacing portion 19 is for example made up of a dielectric to ensure electrical insulation between the luminous elements, the luminous containment walls 16 and / or support face lia.

[0102] The spacing portion 19 is for example formed by a passivation layer at least partly transparent to the light emitted by the light element 13 around which it is arranged.

[0103] The spacing portion 19 is for example formed between the lateral surfaces of the light containment walls 16 and the lateral walls of the light elements 13.

[0104] In the case where the light elements are formed solely of a wire light-emitting diode, the spacing portion 19 is for example formed between the lateral surfaces of the light-containing walls 16 and the longitudinal extension walls of the light-emitting diode.

[0105] The spacing portion 19 is also possibly formed from the support face 1 la until it covers all or part of the light containment walls 16.

[0106] Combined or independently, the spacing portion 19 can be formed in whole or in part by a light conversion layer encompassing color converters such as photoluminescent pads. These are capable of converting at least a first wavelength of the light emitted, directly or after reflection on at least one of the light confinement walls 16, by the light element 13, into a second wavelength different from the first wavelength.

[0107] As illustrated in [Fig. 10], in combination or independently of the preceding examples, a protective layer 21 can be formed on the portion of the layer A spacing 19 is located on the side opposite the support 11. This protective layer 21 can be formed from a dielectric material, preferably transparent, using any technique known to those skilled in microelectronics, such as atomic layer deposition or plasma-enhanced deposition. This protective layer 21 can also be traversed by openings 20, for example, made by etching. These openings 20 advantageously lead to the light-containing walls 16. Contact with the light-containing walls 16 can thus be re-established and advantageously positioned at the level of the light-containing walls 16 without risk of short circuits. This design is advantageous because the light converters present in the spacing portion 19 are thus protected by the protective layer 21 during the manufacturing steps. This also allows the use of conventional microelectronic methods.

[0108] The invention also relates to a method for manufacturing an optoelectronic device 10 for a light display. As illustrated in Figures 7, 8 and 9, the manufacturing method comprises a step a) of providing a support 11 delimiting a support face 1la. The support 11 is as described above.

[0109] Another step of the process b) consists of the formation of at least one first electrode 13d as described previously.

[0110] A further step of the process (c) consists of forming a plurality of luminous elements 13. These are fixed to the support face 11a directly or indirectly in an electrically isolated manner or so as to be electrically connected to an element of the support 11 as described previously. At the end of step (b), at least one first electrode 13d is electrically connected to at least one of the formed luminous elements 13.

[0111] As described previously, each light element 13 comprises at least one light-emitting diode 15. As described previously, each light-emitting diode 15 has an active part capable of emitting light when a current flows through the active part. As described previously, each light-emitting diode 15 has at least one doped part arranged to be in direct electrical contact, or indirect contact via a control device, with said at least one first electrode 13d.

[0112] The process further comprises an additional step d) consisting of the formation of a plurality of light-containing walls 16. The light-containing walls 16 can be formed, for example, by etching a layer and filling said etching, or conversely, by growth, or even by transfer from an external support. Thus, step d) includes a filling step consisting of filling all or part of the etching resulting from step d) with an electrically conductive material.

[0113] Each light-containing wall 16 formed has the ability to reflect all or part of the light emitted by at least one of the light elements 13 as described above. Each light-containing wall 16 is also arranged to surround all or part of said at least one of the light elements 13 so as to reflect all or part of the light emitted by said at least one light element 13. This reflection occurs along one or more preferred directions, or omnidirectionally. Step d) is such that all or part of at least one of the light-containing walls 16 has the ability to be electrically conductive and is electrically connected to the first electrode 13d of at least one of the light elements 13 of said plurality of light elements 13.By connected, we mean either connected directly by physical contact, or connected indirectly via electrically conductive intermediate layers.

[0114] The steps are indexed according to the letters a, b, c etc., but this does not in any way imply that these steps are successive in time. For example, step c) can advantageously be implemented after the formation, on the support 11, of the luminous elements 13.

[0115] In an example illustrated in [Fig. 8], the manufacturing process includes the additional step e), carried out between steps b) and d). Step e) consists of forming a spacer portion 19 as described previously. The spacer portion 19 is formed on said at least one first electrode 13d formed in step b) on a side opposite the support 11. In this example, the light-containing walls 16 are formed during step d) through the spacer portion 19 formed in step e) to be in physical and electrical contact with the first electrode 13d formed in step b). To do this, a dry or wet etching can be used, followed by filling, for example by electrodeposition or by a physical deposition such as plasma-assisted deposition.Thus, in an example illustrated in Figures 8 and 9, step d) includes at least one etching step in which the portion of spacing 19 obtained in step e) undergoes controlled etching so as to stop said etching when the first electrode 13d is reached. Techniques, known as end-of-attack techniques, allow the etching to be stopped precisely.

[0116] In a further example illustrated in [Fig. 9], the process includes an additional step f) of forming an electrically conductive layer 16a in the etching resulting from step d). Step f) is carried out such that the electrically conductive layer 16a formed is in electrical contact with the first electrode 13d formed in step b). The electrically conductive layer 16a is characterized by an electrical conductivity greater than 10⁶ Siemens / m. All or part of step f) is carried out during step d).

[0117] In one embodiment of the process, step c) includes a remote manufacturing step of the luminous elements 13 and their transfer to the support 11. In this step, the luminous elements 13 are obtained on an external support different from the support 11 and then transferred so as to be fixed to the support face 1 of the support 11. This makes it possible to form the luminous elements under conditions that the support would not withstand without damage. This is also advantageous when the support is large, exceeding twenty centimeters, as the luminous elements 13 are often formed on smaller substrates.

[0118] In one example of implementing the process, an additional step g) is carried out. During this step, a protective layer 21 is formed on the layer in the gap portion 19 on the side opposite the support 11. This protective layer 21 can be formed from a dielectric material, preferably transparent, and by any technique known to those skilled in the art of microelectronics, such as atomic layer deposition or plasma-enhanced deposition. In this step g), the protective layer 21 can also be traversed by openings 20, for example, made by etching. These openings 20 advantageously lead to the light-containing walls 16. Contact can thus be re-established on the front face and advantageously positioned at the level of the light-containing walls 16 without risk of short circuits.This architecture is advantageous because the light converters present in the spacing portion 19 are thus protected by the protective layer 21 during the manufacturing stages.

Claims

Demands

1. Optoelectronic device (10) for luminous display, comprising: -a support (11) delimiting a support face (lia); -a plurality of luminous elements (13) fixed to the support face (1la), each luminous element (13) being electrically connected to at least one first electrode (13d) and comprising at least one light-emitting diode (15) having an active part capable of emitting light when a current passes through the active part and at least one doped part arranged in electrical contact with said at least one first electrode (13d), said first electrode (13d) covering at least one upper part of said doped part arranged on the side opposite the support face (lia); -a plurality of light containment walls (16), each light containment wall (16) being configured so as to have an ability to reflect all or part of the light emitted by at least one of the light elements (13) and being arranged so as to surround all or part of said at least one of the light elements (13) so as to reflect all or part of the light emitted by said at least one light element (13); all or part of at least one of the light containment walls (16) of the plurality of light containment walls (16) having the ability to be electrically conductive and directly connected to the first electrode (13d) of at least one of the light elements (13) of said plurality of light elements (13), characterized in that the light elements (13) are connected to a second electrode (13c) electrically isolated from the first electrode (13d), said second electrode (13c) being electrically connected to at least one other light containment wall (16) among the plurality of light containment walls (16), where said other light containment wall (16) is electrically isolated from the light containment wall in electrical contact with the first electrode (13d) of said light element (13).

2. An optoelectronic device (10) according to claim 1, wherein at least one of the light elements (13) of the plurality of light elements (13) comprises all or part of a control device (13b) configured to modulate at least one emission parameter associated with said at least one light-emitting diode (15) comprising said luminous element (13).

3. Optoelectronic device (10) according to claim 2, wherein the control device (13b) of at least one of the light elements (13) is electrically connected to the second electrode (13c).

4. Optoelectronic device (10) according to any one of claims 1 to 3, wherein at least one of the light-emitting diodes (15) of at least one of the light elements (13) has a three-dimensional wire shape extending along a principal axis (18) oriented transversely to the support face (1la), the first electrode (13d) surrounding at least an upper portion (15a) of said light-emitting diode (15) arranged on the side opposite the support face (lia) along the principal axis (18).

5. Optoelectronic device (10) according to claim 4, wherein the first electrode (13d) is arranged at a lower portion of the light-emitting diode (15) located on a side opposite to the upper portion (15a) along the main axis (18).

6. Optoelectronic device (10) according to any one of claims 1 to 5, wherein the first electrode (13d) is formed in an electrically conductive material and at least partially transparent to the light emitted by the active part of the light-emitting diode (15) in contact with said first electrode (13d).

7. Optoelectronic device (10) according to any one of claims 1 to 6, wherein all or part of the first electrode (13d) is covered, on a side opposite the support (11), by a portion of spacing (19) formed on the first electrode (13d), the light confinement walls (16) being formed through said portion of spacing (19) to be in contact with the first electrode (13d).

8. Optoelectronic device (10) according to claim 5, wherein a first electrical conductor (14) is formed on an upper face of the spacing portion (19) arranged on a side opposite the support face (lia) along the main axis (18) such that the first electrical conductor (14) is in electrical contact with at least one of the light confinement walls (16).

9. An optoelectronic device (10) according to claim 7 or 8, wherein said spacing portion (19) is formed by a passivation layer that is at least partially transparent to the light emitted by the light element (13) around which it is arranged and electrically insulating, and / or by a light conversion layer capable of converting at least a first wavelength of the light emitted by the luminous element (13), around which it is arranged, into a second wavelength different from the first wavelength.

10. Optoelectronic device (10) according to any one of claims 1 to 9, wherein at least one of the light confinement walls (16) comprises an electrical conduction layer (16a) characterized by an electrical conductivity greater than 106 Siemens / m.

11. Optoelectronic device (10) according to claim 10, wherein the electrical conduction layer (16a) is formed by at least one element belonging to the group comprising silver, aluminum, a copper-silver alloy, gold, a silver-gold alloy, a gold-aluminum alloy, a tungsten-silver alloy, a tungsten-aluminum alloy.

12. Optoelectronic device (10) according to any one of claims 1 to 11, wherein the support (11) is formed in a material other than a crystalline material.

13. Optoelectronic device (10) according to any one of claims 1 to 12, wherein at least two light containment walls (16) belonging to the plurality of light containment walls (16) are electrically connected to each other.

14. Optoelectronic device (10) according to any one of claims 1 to 13, wherein the light elements (13) are obtained on an external support different from the support (11) prior to a transfer of said light elements (13) to the support (11).

15. Optoelectronic device (10) according to any one of claims 1 to 14, comprising an electrical insulation layer (17) arranged between at least a portion of the support face (1la) and all or part of the first electrode (13d).

16. A method for manufacturing an optoelectronic device (10) for a light display, the manufacturing method comprising the following steps: a) providing a support (11) defining a support face (1a); c) forming a plurality of luminous elements (13) fixed to the support face (1a) and comprising at least one light-emitting diode (15) having an active part capable of emitting light when a current passes through the active part and at least one doped part; b) forming at least one first electrode (13d) covering at least an upper part of said doped part arranged on the side opposite the support face (lia), said doped part being arranged to be in a situation of electrical contact with said at least one first electrode (13d), said at least one first electrode (13d) being electrically connected to at least one of the luminous elements (13) formed;d) formation, after step b), of a plurality of light containment walls (16) in which each light containment wall (16) formed has the ability to reflect all or part of the light emitted by at least one of the light elements (13) and is arranged so as to surround all or part of said at least one of the light elements (13) so as to reflect all or part of the light emitted by said at least one light element (13), step d) being such that all or part of at least one of the light containment walls (16) of the plurality of light containment walls (16) has the ability to be electrically conductive and directly connected to the first electrode (13d) of at least one of the light elements (13) of said plurality of light elements (13).;

17. A manufacturing method according to claim 16, comprising the following step, carried out between step b) and step d): e) formation of a spacing portion (19) on said at least a first electrode (13d) formed in step b) on a side opposite the support (11); the light confinement walls (16) being formed during step d) through the spacing portion (19) formed in step e) and to be in contact with the first electrode (13d) formed in step b).

18. A manufacturing method according to claim 17, wherein step d) comprises at least one etching step in which the spacing portion (19) obtained in step e) undergoes controlled etching so as to stop said etching when the first electrode (13d) is flush.

19. A manufacturing method according to claim 18, comprising the following step: f) formation of an electrical conductive layer (16a) in the etching resulting from step d); step f) being carried out so that the electrical conductive layer (16a) formed is in electrical contact with the first electrode (13d) formed in step b) and is characterized by an electrical conductivity greater than 106 Siemens / m; all or part of step f) being implemented during step d).

20. A manufacturing method according to any one of claims 18 or 19, wherein step d) comprises a filling step consisting of filling all or part of the engraving resulting from step d) with an electrically conductive material.

21. A manufacturing method according to any one of claims 16 to 20, wherein step c) comprises a remote manufacturing step of the luminous elements (13) in which the luminous elements (13) are obtained on an external support different from the support (11) and then transferred so as to be fixed on the support face (1la) of the support (H).

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