Optoelectronic device and method for manufacturing an optoelectronic device

Abstract

The optoelectronic device comprises a substrate and a stack of organic layers, including one active layer of a light-emitting layer or photodiode, arranged between a reflective surface and semi-reflective surfaces that are arranged facing each other at a predetermined distance and form an optical cavity with a predetermined optical length d, the device comprising three groups of pixels, each group comprising a cavity with a different optical length d, the cavity comprising a plurality of bilayers arranged between the substrate and the stack of organic layers, each bilayer being formed by a first layer made of a first transparent conductive material and a second layer in direct contact with the first layer and made of a second transparent conductive material different from the first transparent conductive material, characterized in that for each bilayer, the first layer counted from the substrate has a lower resistance to wet etching processes than the second layer, and for each group of pixels beyond the first, the first layer of the bilayer farthest from the substrate is laterally protected by the second layer of the bilayer.

Claims

[Claim 1] Optoelectronic devices, A substrate (150) and A stack of organic layers (370) is provided, which includes a surface of a reflective surface or a transparent layer (680) directly deposited on the reflective surface that protects the reflective surface, and a stack of semi-reflective surfaces arranged facing each other at a predetermined distance and forming an optical resonator of a predetermined optical length d, and which includes at least one active layer that may be an emissive layer (575, 578, 572) or a photodiode, The device is characterized by including at least three pixel (367a, 367b, 367c) groups, each group characterized by an optical resonator having a different optical length d, the optical resonator including a plurality of bilayers disposed between the substrate and the stack of organic layers, each bilayer being formed of a first transparent conductive layer (156, 3561, 3562, 7561, 7562) formed from a first transparent conductive material and a second transparent conductive layer (160, 360, 3601, 3602, 7601, 7602) in direct contact with the first transparent conductive layer and formed from a second transparent conductive material, wherein the first transparent conductive material is different from the second transparent conductive material, and The device described above, - For the first group of pixels (367c), the number of the double layers is 0. - For the second group of pixels (367b), the number of the double layers is 1, - With respect to the third group of pixels (367a), the number of the double layers is 2 or 1, but in the latter case, the first transparent conductive layer of the double layer related to the third group of pixels is thicker than that of the second group of pixels. - For each additional group of pixels, if present, the number of the bilayers increases by one with respect to the number of the bilayers in the preceding group of the first to third groups of pixels, or remains the same, except in the latter case, the first transparent conductive layer of the bilayer associated with the additional group of pixels is thicker than that of the preceding group of the first to third groups of pixels. - The groups are numbered 1st, 2nd, 3rd, and any subsequent numbers in order of increasing value of d, and The device is such that, for each of these bilayers, the first transparent conductive layer closer to the substrate than the second transparent conductive layer has lower resistance to wet etching than the second transparent conductive layer, and for each group of pixels other than the first group, at least the first transparent conductive layer of the bilayer furthest from the substrate is protected laterally by the second transparent conductive layer of the bilayer. The optoelectronic device is characterized in that, in the wet etching treatment with an aqueous solution of 2.38 wt% tetramethylammonium hydroxide at ambient temperature, the specific etching rate V1 of the first permeable conductive layer is at least 10 times that of the specific etching rate V2 of the second permeable conductive layer. [Claim 2] The device according to claim 1, characterized in that, for each group of pixels other than the first group, the first transparent conductive layer of the bilayer furthest from the substrate is completely sealed by the second transparent conductive layer of the bilayer. [Claim 3] The device according to claim 1 or 2, characterized in that, for each group of pixels other than the first group, all of the first transparent conductive layers of the bilayer are completely sealed by the second transparent conductive layer of the second transparent conductive material. [Claim 4] The device according to any one of claims 1 to 3, characterized in that the reflective surface is covered by the permeable layer (680) of the second permeable conductive material. [Claim 5] The first permeable conductive material is characterized by being selected from the group formed by ZnO, an oxide containing doped ZnO, indium oxide, and / or an oxide containing doped indium oxide, and / or The second permeable conductive material is SnO ２ , doped SnO ２ The optoelectronic device according to any one of claims 1 to 4, characterized in that it is selected in a group formed by the above. [Claim 6] The device according to any one of claims 1 to 5, characterized in that the stack of organic layers (370) is in direct contact with the reflective surface or the transparent layer (680) deposited on the reflective surface, and / or with the semi-reflective surfaces (166, 266, 366, 466) on the other. [Claim 7] The device according to any one of claims 1 to 6, characterized in that the stack of organic layers forms a continuous coating over all pixels. [Claim 8] The device according to claim 7, characterized in that the stack of organic layers includes semi-permeable conductive layers (166, 266, 366) deposited on the stack of organic layers (370) and forming a continuous coating over all pixels. [Claim 9] The optoelectronic device according to any one of claims 1 to 8, characterized in that the substrate (150) is a CMOS type substrate equipped with a circuit that enables individual addressing or individual reading of the pixels. [Claim 10] The optoelectronic device according to any one of claims 1 to 9, characterized in that it is an organic light-emitting diode microdisplay or a multispectral light sensor. [Claim 11] A method for manufacturing an optoelectronic device according to any one of claims 1 to 10, - First, the third permeable conductive layer (156, 3561) of the first permeable conductive material is deposited on the reflective surface, or on the permeable layer of the second permeable conductive material deposited on the reflective surface, - A step of defining the second and third pixel (367b, 367a) groups and depositing a first mask that protects their positions, - The third transparent conductive layer (156, 3561) is removed by wet etching at locations not protected by the first mask, where these unprotected locations constitute locations for the first pixel group (376c), and then the first mask is removed. - A step of depositing a fourth permeable conductive layer (3601) of the second permeable conductive material, - A step of depositing a fifth permeable conductive layer (3562) of the first permeable conductive material, - A step of defining the third pixel (367a) group and depositing a second mask (332a) to protect its position, - The steps of removing the fifth transparent conductive layer (3562) of the first transparent conductive material by wet etching the areas not protected by the second mask, so that these unprotected areas constitute the areas for the second pixel (367b) group and the first pixel (367c) group, and then removing the second mask, - A step of depositing a sixth permeable conductive layer (3602) of the second permeable conductive material, - A step of defining the first, second, and third pixel groups and depositing a third mask (3620a, 3620b, 3620c) to protect their positions, A method for manufacturing an optoelectronic device, comprising the step of removing the fourth transparent conductive layer (3601) and the sixth transparent conductive layer (3602) of the second transparent conductive material, as well as the reflective surface (152), and, if present, the transparent layer (680) of the second transparent conductive material covering them, by dry etching at locations not protected by the third mask. [Claim 12] A method for manufacturing an optoelectronic device having three pixel groups as described in claim 11, - A step of depositing filling elements (364) in each space between two adjacent pixels, - A step of depositing a stack of organic layers (370) common to all pixels, and depositing a semi-reflective electrode layer (366) common to all pixels on top of the stack of organic layers, A method for manufacturing optoelectronic devices, which involves performing the following steps in succession. [Claim 13] The method according to claim 11 or 12, wherein the deposition of the fourth and sixth permeable conductive layers of the second permeable conductive material is carried out by atomic layer deposition technique.

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