Method for depositing layers of organic / inorganic hybrid or inorganic materials onto a substrate - Patent Application 20070122997

Abstract

The present invention relates to a process for depositing a layer of inorganic or organic / inorganic hybrid material on a substrate for the manufacture of electronic, optoelectronic and / or optical devices, comprising the steps of preparing a target, placing the target on a susceptor in a sublimation furnace, said target being placed in the furnace facing the substrate to be coated, and heating the target via the susceptor in order to deposit a layer of inorganic or organic / inorganic hybrid material on the substrate by sublimation, wherein the target comprises a plurality of partial targets, and wherein the step of preparing the targets makes it possible to obtain partial targets with variable thicknesses and / or wherein the step of preparing the targets makes it possible to obtain overlapping partial targets.

Description

[Technical Field]

[0001] The present invention relates to the deposition of layers of inorganic or organic / inorganic hybrid materials, such as perovskites, by sublimation. In particular, the present invention uses targets comprising several sub-targets and having a large surface area (typically 25 cm²). 2 Deposition by sublimation allows for the deposition of a uniform layer over a surface area of ​​1000 nm or more. [Background technology]

[0002] The deposition of layers of inorganic or organic / inorganic hybrid materials is used in various applications, such as the manufacture of electronic, optical, or optoelectronic devices based on inorganic or organic / inorganic hybrid materials (e.g., LEDs, photodetectors, scintillators, or transistors). Currently, it is possible to deposit layers of inorganic or organic / inorganic hybrid materials, such as perovskites, using the close-space sublimation (CSS) method. For this purpose, a target containing the inorganic or organic / inorganic hybrid material is placed on a susceptor in a close-space sublimation furnace, facing the substrate on which the layer is to be deposited. The furnace also includes a heating system and a pumping system that allows a vacuum to be achieved within the furnace. When the target is heated by the heating system, the material from the target sublimes and condenses on the substrate. The deposition is directional, i.e., the geometry of the target is replicated in the geometry of the deposit (so that the surface of the deposit is identical to that of the target). This is because the sublimation is perpendicular to the target surface, and the mean free path of the substance in the gas phase is equal to or greater than the distance between the target and the substrate.

[0003] The targets are manufactured as compressed powders, which makes it possible to obtain solid targets of uniform thickness and therefore uniform layers deposited on the substrate. However, large surface areas (e.g., 25 cm) are required. 2During deposition to ultra-large (super-large), obtaining a target with a large surface area of ​​deposition is difficult. In particular, the pressure density to create the target must be constant, so the force applied by the press must increase proportionally to the surface area. Thus, a press that exerts a high pressure is required for a large surface area. Furthermore, due to the friability of the compressed powder and the thin thickness of the target, a higher pressure density may be required to obtain a solid target with a large surface area and a uniform thickness.

[0004] Therefore, it is possible to manufacture a target in the form of a tiling, i.e., several partial targets, each representing a portion of the target. The apparent surface area of ​​the partial targets, which form the size of the deposit, is arranged as a continuous surface area (i.e., without "holes"). In other words, partial targets are targets with smaller surface areas that can be later assembled on a susceptor. Targets with smaller surface areas can be manufactured more easily because they do not require a high-pressure press. For example, as shown in FIG. 1, there are targets that include a tiling of partial targets, which have rectangular or square partial targets and represent a target including four partial targets when viewed from above. Summary of the Invention [Problem to be solved by the invention]

[0005] However, sublimation occurs not only perpendicular to the top surface of the tiling target but also along the edge of the target. As a result, the surface area of ​​the target decreases during deposition, the target splits, and the deposition at the joint becomes thinner. Therefore, a simple tiling such as that shown in Figure 1 cannot achieve uniform deposition. [Means for solving the problem]

[0006] In response to problems encountered in the art, the subject matter of the present invention is a method for producing a large surface area (typically 25 cm 2 It is a process in which a uniform layer of inorganic or organic / inorganic hybrid material is deposited by sublimation on a substrate (or substrates with a surface area of ​​1000 or more).

[0007] In particular, the present invention improves the situation by providing a process for depositing a layer of inorganic or organic / inorganic hybrid material on a substrate for the manufacture of electronic, optoelectronic and / or optical devices, comprising the steps of preparing a target, placing the target on a susceptor in a sublimation furnace, said target being placed in the furnace facing the substrate to be coated, and heating the target via the susceptor in order to deposit a layer of inorganic material on the substrate by sublimation, characterized in that the target comprises a plurality of partial targets, and the step of preparing the targets makes it possible to obtain partial targets with variable thicknesses and / or that the step of preparing the targets makes it possible to obtain overlapping partial targets.

[0008] As mentioned above, sublimation occurs not only in the center of the partial target, but also on the edge surfaces of the tiling partial targets. The present invention is particularly advantageous because it makes it possible to compensate for sublimation on the edge surfaces by providing a non-uniform thickness and / or overlapping several partial targets. Thus, it is possible to manufacture partial targets that allow the sublimation of material onto substrates with a large surface area while obtaining a uniform sublimation layer. Furthermore, the present invention is particularly advantageous because it does not require the use of a high-pressure press, thus simplifying the manufacture of the target.

[0009] In one embodiment, each partial target has a central region and a peripheral region, the thickness of the partial target being greater in the peripheral region.

[0010] In one embodiment, at least two partial targets of the target are interlocking.

[0011] In one embodiment, the two partial targets are beveled.

[0012] In one embodiment, the two partial targets are square wave shaped.

[0013] In one embodiment, the partial targets overlap to form several layers.

[0014] In one embodiment, each layer has the same thickness.

[0015] In one embodiment, each tier has a different thickness.

[0016] In one embodiment, at least two layers are made of different materials.

[0017] In one embodiment, the partial targets overlap randomly.

[0018] In particular, the invention improves the situation by providing a target for carrying out the deposition of one or more layers of inorganic or organic / inorganic hybrid materials on a substrate by sublimation, the target being formed of several partial targets, the partial targets having variable thicknesses and / or overlapping.

[0019] The invention will be better understood and other advantages will become apparent on reading the following non-limiting description and from the figures, in which: [Brief explanation of the drawings]

[0020] [Figure 1] 1 shows an example of a prior art target with simple tiling. [Figure 2] 1 illustrates an example process for depositing one or more layers of inorganic or organic / inorganic hybrid materials onto a substrate by sublimation. [Figure 3] 1 illustrates an example of a system for depositing one or more layers of inorganic or organic / inorganic hybrid materials onto a substrate by sublimation. [Figure 4a] 1 illustrates an example of a target including partial target tiling in a cross-sectional view. [Figure 4b] 1 illustrates an example of a target including partial target tiling in a cross-sectional view. [Figure 5]1 illustrates an example of a target including partial target tiling in a cross-sectional view. [Figure 6a] 1 illustrates a cross-sectional view of an example target including partial target tiling. [Figure 6b] 1 illustrates a cross-sectional view of an example target including partial target tiling. [Figure 6c] 1 illustrates a cross-sectional view of an example target including partial target tiling. DETAILED DESCRIPTION OF THE INVENTION

[0021] FIG. 2 illustrates a process for depositing 100 a layer of inorganic or organic / inorganic hybrid material on a substrate 302 for the fabrication of electronic, optoelectronic and / or optical devices.

[0022] In block 1002, the process 1000 includes preparing targets 500a, 500b, 500c, 500d, 500e, and 500f. As shown in Figures 4a-6c, which depict example targets, the targets 500a, 500b, 500c, 500d, 500e, and 500f include multiple partial targets 502. Preparing the targets 500a, 500b, 500c, 500d, 500e, and 500f allows for obtaining partial targets 502 with varying thicknesses and / or preparing the targets 500a, 500b, 500c, 500d, 500e, and 500f allows for obtaining overlapping partial targets. In particular, Figures 4a, 4b, 6a, 6b, and 6c depict targets 500a, 500b, 500d, 500e, and 500f having overlapping partial targets 502, and Figure 5 depicts target 500c having partial targets with variable thicknesses. The thickness of a partial target represents one dimension. In particular, the thickness of a partial target represents the distance between the bottom surface of the partial target (the surface that contacts the susceptor 306) and the top surface opposite the bottom surface.

[0023] For example, when partial targets overlap, the partial targets 502 form a target in which multiple partial targets overlap in the thickness of the target over a small portion (1% to 25%) of the total surface area of ​​the target. The overlap can be established over a few millimeters (0.5 mm to 10 mm, preferably 2 mm). In another example, when partial targets overlap, the target includes multiple partial targets 502 overlapping in the thickness of the target over the entire surface area of ​​the target. This overlap can be obtained with any number of partial targets greater than two (preferably less than five). The overlap can be ordered (in particular an ordered arrangement of partial targets characterized by the same number of overlapping partial targets in the thickness at each point of the tiling) or disordered.

[0024] Each partial target includes a peripheral region and a central region. The peripheral region represents the entire periphery of the partial target. In Figures 4a, 4b, 4c, and 5, the thickness of the central region is different from the thickness of the peripheral region. For example, as shown in Figures 4a and 4b, at least two partial targets 502 of target 500a are interlocking. In particular, in Figure 4a, the partial targets 502 are beveled. In the example of Figure 4b, the partial targets 502 are rectangular wave-shaped. In particular, in these two examples, targets 500a and 500b include at least three partial targets: a first partial target, a second partial target, and a third partial target. The three partial targets are arranged side by side. Each partial target has the same volume, the same bevel, and an upper and lower side, one side being larger than the other. In the first and third partial targets, the lower side is larger than the upper side, and in the second partial target, the upper side is larger than the lower side.

[0025] In another example, the target 500a may include a beveled partial target 502 and a square wave shaped partial target 502.

[0026] In another example, as shown in Figure 5, each partial target 502 has a central region and a peripheral region, with the thickness of the partial target 502 being greater in the peripheral region. The thickness may vary gradually, as shown in Figure 5, or may vary abruptly (i.e., with a rim disposed on the partial target 502, for example). Note that Figure 5 is a cross-sectional view, and therefore the thickness variation is only represented at two of the ends of the partial target 502.

[0027] In another example, as shown in FIGS. 6a-6c, partial targets overlap to form several layers. The partial targets include two ends. When the partial targets form layers, the end of one partial target does not coincide with the end of a partial target above or below the layer. For example, in the example of FIGS. 6a and 6b, the thickness of each layer is the same. In the example of FIG. 6c, the thickness of each layer is different. Additionally, in the example of FIG. 6c, the partial targets 502 overlap in a disordered manner. In another example, the layers can have different thicknesses while overlapping each other in an orderly manner.

[0028] It should be noted that the targets 500a, 500b, 500c, 500d, 500e, and 500f in Figures 4a to 6c are represented in cross section. In top view, the partial targets 502 can be rectangular, square, or parallelepiped. In other examples, the partial targets can be circular, triangular, or any other shape suitable for the application in which the targets 500a, 500b, 500c, 500d, 500e, and 500f are used. The number of partial targets 502 is also adapted to the dimensions of the substrate 302 onto which the layer of inorganic or organic / inorganic hybrid material is to be sublimated. For example, in the example of Figure 4a, the target 500a includes three partial targets 502 in cross section. The target 500a can also include two or more partial targets 502. When viewed from the top, the target 500a may form a square, a rectangle, or any other shape suitable for the application in which the targets 500a, 500b, 500c, 500d, 500e, 500f are used.

[0029] Targets 500a, 500b, 500c, 500d, 500e, and 500f are formed using compressed powders of inorganic or organic / inorganic hybrid materials. Each partial target 502 is fabricated individually, and then the partial targets are assembled to form targets 500a, 500b, 500c, 500d, 500e, and 500f. A target may be made of a single material. Thus, each partial target of the same target may be made of the same material or the same mixture of materials.

[0030] The targets 500a, 500b, 500c, 500d, 500e, 500f are made of inorganic or organic / inorganic hybrid materials, and the materials are, for example, A (n) and B (n) Cation and X (n) A with anion (1) 1-(y2+...+yn) A (2) y2 ...A (n) yn B (1) 1-(z2+...+zm) B (2) z2 ...B (m) zm X (1) 3-(x2+...+xp) X (2) x2 ...X (p) xp The perovskite may be a perovskite of the general formula ABX3, including mixed compositions such as those having the general formula ABX3, where the composition exhibits electron neutrality and y2 and yn are cations A, B, C, D, E ... (2) and A (n) are the respective ratios of z2 and z m is cation B (2) and B (m) are the respective proportions of x2 and x p is the anion X (2) and X (p) are the respective proportions of

[0031] For example, A is selected from Cs, Rb, K, Li, Na (inorganic perovskites) or CH3NH3, CH5N2 (hybrid perovskites), B is selected from Pb, Sn, Ge, Hg, Cd, and X is selected from Cl, Br, I, F. For example, it is CsPbBr3.

[0032] In another example, alloys of 2 to 5 elements can be applied to one site, two sites, or three sites A, B, and X. For example, X=Cl. k Br l I 1-k-l (where 0≦k, l≦1, 0≦k+l≦1). The same is true for sites A and B.

[0033] In another example, A=A'2, B=C' 1+ D' 3+ and X3 = X'6, i.e., the chemical formula is A'2C 1+ D 3+ It is also possible to have a dual cell with materials A' selected from Cs, Rb, K, Li and Na, X' selected from Cl, Br, I and F, and C' 1+ is selected from Ag, Au, Tl, Li, Na, K and Rb, and D 3+ is selected from Al, Ga, In, Sb and Bi.

[0034] Preferably, according to this alternative, the perovskite material has the formula Cs2AgBiBr6.

[0035] The present invention is applicable to all other compositions similar to perovskites, e.g., CsTe 4+ Composition A2B such as I6 4+ Materials with X6, such as Cs3Bi2I9, with the composition A3B2 3+ It can also be applied to materials with X9 or other types of materials (chalcogenides, rudolphite, etc.).

[0036] If the chemical formula of the targets 500a, 500b, 500c, 500d, 500e, 500f is ABX3, the targets 500a, 500b, 500c, 500d, 500e, 500f may be formed of a mixture of elementary particles A, B and X.

[0037] In another example, targets 500a, 500b, 500c, 500d, 500e, 500f having the chemical formula ABX3 are - a mixture of binary particles of AX and BX2, - a mixture of AX, BX2 and ABX3 particles, - ABX3 particles Since the particles can be formed from the appropriate composition and phase of the material to be sublimed, the particles can be small single crystals formed, for example, by the liquid route, the Bridgman route, or other methods.

[0038] It is also possible to use mixtures containing more than two types of binary particles, for example the compound Cs2AgBiBr6 can be obtained from CsBr, AgBr and BiBr3 precursors.

[0039] The chemical formula of target 20 is A'2C 1+ D 3+ If it is X6, the target - A'X, C 1+ X and D 3+ mixture of X3 binary particles, - A'X, C 1+ X, D 3+ X3 and A'2C 1+ D 3+ A mixture of X6 particles, - A'2C 1+ D 3+ X6 particles Since the material can be synthesized from the appropriate composition and phase of the material to be sublimed, it is possible to directly obtain the appropriate composition and phase of the material to be sublimed.

[0040] Compositions containing more complex and / or more precursors are also contemplated. 1-x-y Hg x Zn y Te 1-z-tSe z S t (where 0≦x, y, z, t≦1), Sb2(S 1-x Se x Other inorganic or organic / inorganic hybrid materials such as )3 (where 0≦x≦1) or other materials that can be deposited by close space sublimation can also be used.

[0041] In the above example, each of the targets 500a, 500b, 500c, 500d, 500e, and 500f measures at least 5 cm in width, i.e., at least one side of the target measures at least 5 cm. In one example, the width of the targets 500a, 500b, 500c, 500d, 500e, and 500f measures at least 10 cm. In another example, the width of the targets 500a, 500b, 500c, 500d, 500e, and 500f measures at least 20 cm.

[0042] In one example, targets 500a, 500b, 500c, 500d, 500e, and 500f include partial targets made of different materials. For example, targets 500a, 500b, 500c, 500d, 500e, and 500f include at least two layers made of different materials. For example, in the example of FIG. 6b, target 500e includes two layers, an upper layer and a lower layer. The upper layer can be made of a first material, and the lower layer can be made of a second material. In another example, FIG. 5 shows target 500c including three partial targets 502, a first partial target, a second partial target, and a third partial target. The first partial target can be made of a first material, the second partial target can be made of a second material, and the third partial target can be made of a third material.

[0043] In block 1004, the process 1000 includes placing the targets 500a, 500b, 500c, 500d, 500e, and 500f on a susceptor 306 within the sublimation furnace 308 such that the targets 500a, 500b, 500c, 500d, 500e, and 500f are positioned facing the substrate 302 to be coated within the furnace 308. The targets 500a, 500b, 500c, 500d, 500e, and 500f can be fabricated on the susceptor 306, for example, which is subsequently placed within the furnace 308. In another example, the targets 500a, 500b, 500c, 500d, 500e, and 500f can be fabricated on a support and transferred to the susceptor 306. The furnace can be a close-space sublimation furnace. The susceptor 306 is made of a conductive material. The furnace 308 includes a gas outlet that can be connected to a pumping system to achieve a vacuum P range of, for example, 0.00001 Pa to 1 Pa. The P value depends on the furnace 308 used.

[0044] In block 1006, the process 1000 includes heating the targets 500a, 500b, 500c, 500d, 500e, 500f via the susceptor 306 to deposit a layer of inorganic material on the substrate 302 by sublimation. For example, as shown in FIG. 3 , which depicts a system 300 for depositing a layer of inorganic material or organic / inorganic hybrid material on the substrate 302 by sublimation, the susceptor 306 can be disposed on a heating element 304. For example, the heating element 304 can be a lamp, a resistor, or any other heating system. Deposition by sublimation is performed by heating the susceptor 306 with the heating element 304 to a temperature of, for example, 400° C. (±100° C.) and a substrate temperature of 300° C. (±150° C.). To ensure layer deposition, the temperature of the substrate is 100°C lower (300°C to 20°C lower) than the temperature of the targets 500a, 500b, 500c, 500d, 500e, 500f. The temperature ramp rate until the sublimation temperature is reached can be, for example, 1°C / s. The temperature can be adjusted depending on the material and thickness of the target.

[0045] The invention described above therefore allows to obtain uniform layers of inorganic or organic / inorganic hybrid materials even on large substrates, since partial targets allow to easily produce solid targets. In addition, partial targets with overlapping and / or variable thickness make it possible to compensate for the fact that sublimation occurs more quickly at the edge of tiling partial targets than in the center of the partial targets.

[0046] Although the present invention has been shown and described in detail using preferred embodiments, the present invention is not limited to the disclosed examples. Those skilled in the art can derive other alternatives without departing from the scope of protection of the claimed invention. For example, the number of partial targets per target may vary depending on the application. Furthermore, the shape, thickness and number of layers of the partial targets may vary depending on the application. Shapes may also be combined.

Claims

1. 1. A process for depositing a layer of inorganic or organic / inorganic hybrid material on a substrate for the production of an active layer in an electronic, optoelectronic and / or optical device, comprising: - preparing a target; - placing the target on a susceptor in a sublimation furnace, the target being placed in the furnace facing the substrate to be coated; heating the target through the susceptor to deposit a layer of the inorganic or organic / inorganic hybrid material on the substrate by sublimation; wherein the target comprises a plurality of partial targets, each partial target having a central region and a peripheral region, and wherein the step of preparing the target makes it possible to obtain partial targets with variable thicknesses, the thickness of the central region being different from the thickness of the peripheral region, and / or wherein the step of preparing the target makes it possible to obtain overlapping partial targets.

2. The deposition process of claim 1 , wherein each partial target has a central region and a peripheral region, and the thickness of the partial target is greater in the peripheral region.

3. The deposition process of claim 1 , wherein at least two partial targets of the target are interlocking.

4. The deposition process of claim 3 , wherein the two partial targets are beveled.

5. The deposition process of claim 3 , wherein the two partial targets are square wave shaped.

6. The deposition process of claim 1 , wherein the partial targets overlap to form several layers.

7. The deposition process of claim 6 , wherein each layer has the same thickness.

8. The deposition process of claim 6 , wherein each layer has a different thickness.

9. The deposition process according to any one of claims 6 to 8, wherein at least two layers are made of different materials.

10. The deposition process of claim 1 , wherein the partial targets overlap randomly.

11. 1. A target for carrying out the deposition of one or more layers of inorganic or organic / inorganic hybrid materials on a substrate by sublimation, the target being formed of several partial targets, each partial target having a central region and a peripheral region, the partial targets having variable thicknesses, the thickness of the central region being different from the thickness of the peripheral region, and / or the partial targets overlapping each other.

Images