WO2022175703A1

WO2022175703A1 - Crucible, distribution pipe, material deposition assembly, vacuum deposition system and method of manufacturing a device

Info

Publication number: WO2022175703A1
Application number: PCT/IB2021/051284
Authority: WO
Inventors: Julian AULBACH; Andreas MÜLLER; Sebastian Franke; Norbert SPATZ; Uwe Schüssler
Original assignee: Applied Materials, Inc.
Priority date: 2021-02-16
Filing date: 2021-02-16
Publication date: 2022-08-25
Also published as: KR20230132853A; CN116802337A

Abstract

A material deposition assembly for depositing a material on a substrate in a vacuum deposition chamber is described. The material deposition assembly includes at least one material deposition source. The deposition source includes a distribution pipe configured for directing evaporated material to the substrate, the distribution pipe having a counterpart flange with a counterpart spheroid surface being rotational symmetric about an axis of circular symmetry, the counterpart spheroid surface having a first height along the axis. The deposition source includes a crucible to evaporate the material, the crucible having a flange with a spheroid surface being rotational symmetric about the axis, the spheroid surface having a second height along the axis, wherein the second height is different from the first height, particularly the second height is different by at least 20% relative to the first height.

Description

CRUCIBLE, DISTRIBUTION PIPE, MATERIAL DEPOSITION ASSEMBLY, VACUUM DEPOSITION SYSTEM AND METHOD OF MANUFACTURING

A DEVICE TECHNICAL FIELD

[0001] Embodiments of the present disclosure relate to sealing of high temperature evaporators, particularly for metal or metal alloy evaporation. Further, embodiments relate to deposition of materials for OLED manufacturing. In particular, embodiments relate to evaporation of metals and metal alloys. Specifically, embodiments relate to an evaporation source, a material deposition assembly, e.g. an evaporation source array, and methods of manufacturing a device. Further, embodiments of the present disclosure relate to deposition apparatuses for depositing one or more layers, particularly layers including metals and metal alloys during OLED device manufacturing, on a substrate. In particular, embodiments of the present disclosure relate to a crucible, a distribution pipe, a material deposition assembly, a vacuum deposition system and methods of manufacturing a device.

BACKGROUND

[0002] Metallic evaporators are tools used for the production of, for example, organic light-emitting diodes (OLED). However, also other applications utilize evaporators for depositing metal layers, for example, on large area substrates. OLEDs are a special type of light-emitting diode in which the emissive layer comprises a thin- film of certain organic compounds. Organic light emitting diodes (OLEDs) are used in the manufacture of television screens, computer monitors, mobile phones, other hand-held devices, etc., for displaying information. OLEDs can also be used for general space illumination. An OLED display, for example, may include layers of organic material situated between two electrodes that are deposited on a substrate in a manner to form a matrix display panel having individually energizable pixels.

[0003] OLED displays or OLED lighting applications include a stack of several organic materials and metal or metal alloys, which are for example evaporated in a vacuum deposition system. For the fabrication of OLED stacks, co-evaporation of two or more metals or metal alloys is provided. An OLED display, for example, may include layers of organic material situated between two electrodes that are deposited on a substrate. One of these electrodes can include a transparent conductive layer such as ITO or other transparent conductive oxide materials (TCO). The second electrode can include a metal or a metal alloy. As a protective layer or a layer for reducing electron affinity, often a very thin layer of lithium fluoride between the cathode and the electron transport layer, cesium fluoride or silver can be deposited.

[0004] In light of the high temperature of the metal evaporation, thermal load on the substrates and/or other components during OLED manufacturing can be high. Evaporating metals, and particularly sealing a crucible to be exchanged for refilling of the crucible is very challenging. For example, document WO 2017/008838 describes that an evaporation crucible and a distribution pipe can be welded to each other, such that gaps or slits in the contact area of the evaporation crucible and the distribution pipe can be avoided. Without providing the evaporation crucible and the distribution pipe as one single piece, gaps or slits might be present at the contact area between the evaporation crucible and the distribution pipe.

[0005] Accordingly, an improved metal or metal alloy evaporation device and an improved metal or metal alloy evaporation is beneficial.

SUMMARY

[0006] In light of the above, a crucible, a distribution pipe, a material deposition assembly, a vacuum deposition system and a method of manufacturing a device according to the independent claims are provided. Further aspects, benefits, and features of the present disclosure are apparent from the claims, the description, and the accompanying drawings.

[0007] According to one embodiment, a material deposition assembly for depositing a material on a substrate in a vacuum deposition chamber is provided. The material deposition assembly includes at least one material deposition source. The deposition source includes a distribution pipe configured for directing evaporated material to the substrate, the distribution pipe having a counterpart flange with a counterpart spheroid surface being rotational symmetric about an axis of circular symmetry, the counterpart spheroid surface having a first height along the axis. The deposition source includes a crucible to evaporate the material, the crucible having a flange with a spheroid surface being rotational symmetric about the axis, the spheroid surface having a second height along the axis, wherein the second height is different from the first height, particularly the second height is different by at least 20% relative to the first height.

[0008] According to one embodiment, a crucible to evaporate a material is provided. The crucible includes an enclosure to evaporate the material and a flange coupled to the enclosure. The flange includes a spheroid surface being rotational symmetric about an axis of circular symmetry, the spheroid surface having a second height along the axis, and an opening for trespassing of evaporated material having an opening size, wherein the second height is 30% or less relative to the opening size.

[0009] According to one embodiment, a distribution pipe for directing evaporated material in a vacuum processing system is provided. The distribution pipe includes a distribution housing having one or more openings for directing the evaporated material and a counterpart flange coupled to the distribution housing. The counterpart flange includes a counterpart spheroid surface being rotational symmetric about an axis of circular symmetry, the counterpart spheroid surface having a second counterpart height along the axis, and an counterpart opening for trespassing of evaporated material having an counterpart opening size, wherein the second counterpart height is 30% or less than the counterpart opening size.

[0010] According to one embodiment, a vacuum deposition system is provided. The vacuum deposition system includes a vacuum deposition chamber and a material deposition assembly according to any of the embodiments described herein in the vacuum deposition chamber. The vacuum deposition system includes a substrate support configured for supporting the substrate during material deposition.

[0011] According to one embodiment, a method of manufacturing a device is provided. The device having at least one metallic layer with a material deposition assembly having at least one material deposition source with a crucible according to any of the embodiments described herein and a distribution pipe. The method includes inserting the crucible into a compartment of the at least one material deposition source, applying a contact force at a connection between the crucible and the distribution pipe, and evaporating a metal to deposit the at least one metallic layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments. The accompanying drawings relate to embodiments of the disclosure and are described in the following:

[0013] FIG. 1A shows a schematic cross-sectional side view of a lower portion of a material deposition assembly according to embodiments described herein, wherein the crucible holding arrangement is disassembled from the material deposition source;

[0014] FIG. IB shows a schematic cross-sectional side view of a lower portion of a material deposition assembly according to embodiments described herein, wherein the crucible holding arrangement is fixed to the material deposition source; [0015] FIG. 2A shows a cross-sectional view of a portion of a flange, particularly a flange of a crucible having a sealing surface, according to embodiments described herein;

[0016] FIG. 2B shows a cross-sectional view of a portion of a flange, particularly a flange of a crucible having a sealing surface, according to embodiments described herein;

[0017] FIG. 2C shows a cross-sectional view of a portion of a flange, particularly a flange of a crucible having a sealing surface, according to embodiments described herein; [0018] FIG. 3 A shows a schematic view of a pressing mechanism for high temperatures according to embodiments described herein;

[0019] FIG. 3B shows a schematic cross-sectional side view of a material deposition assembly according to embodiments described herein;

[0020] FIG. 4 shows a schematic side view of a material deposition assembly according to further embodiments described herein;

[0021] FIG. 5 shows a more detailed schematic cross-sectional top view of a material deposition assembly according to further embodiments described herein as exemplarily shown in FIG. 4;

[0022] FIG. 6 shows a schematic view of a vacuum deposition system according to embodiments described herein with a valve being in an open state; and

[0023] FIG. 7 shows a flow chart illustrating a method of manufacturing a device according to embodiments described herein. DETAILED DESCRIPTION OF EMBODIMENTS

[0024] Reference will now be made in detail to the various embodiments, one or more examples of which are illustrated in each figure. Each example is provided by way of explanation and is not meant as a limitation. For example, features illustrated or described as part of one embodiment can be used on or in conjunction with any other embodiment to yield yet a further embodiment. It is intended that the present disclosure includes such modifications and variations.

[0025] Within the following description of the drawings, the same reference numbers refer to the same or to similar components. Generally, only the differences with respect to the individual embodiments are described. Unless specified otherwise, the description of a part or aspect in one embodiment can apply to a corresponding part or aspect in another embodiment as well.

[0026] Before various embodiments of the present disclosure are described in more detail, some aspects with respect to some terms and expressions used herein are explained.

[0027] In the present disclosure, a “material deposition assembly” is to be understood as an arrangement configured for material deposition on a substrate as described herein. In particular, a “material deposition assembly” can be understood as an assembly configured for deposition of materials, e.g. for OLED display manufacturing, on large area substrates. For instance, a “large area substrate” can have a main surface with an area of 0.5 m² or larger, particularly of 1 m² or larger. In some embodiments, a large area substrate can be GEN 4.5, which corresponds to about 0.67 m² of substrate (0.73x0.92m), GEN 5, which corresponds to about 1.4 m² of substrate (1.1 m x 1.3 m), GEN 7.5, which corresponds to about 4.29 m² of substrate (1.95 m x 2.2 m), GEN 8.5, which corresponds to about 5.7 m² of substrate (2.2 m x 2.5 m), or even GEN 10, which corresponds to about 8.7 m² of substrate (2.85 m x 3.05 m). Even larger generations such as GEN 11 and GEN 12 and corresponding substrate areas can similarly be implemented. [0028] The term “substrate” as used herein may particularly embrace substantially inflexible substrates, e.g., a wafer, slices of transparent crystal such as sapphire or the like, or a glass plate. However, the present disclosure is not limited thereto, and the term “substrate” may also embrace flexible substrates such as a web or a foil. The term “substantially inflexible” is understood to distinguish over “flexible”. Specifically, a substantially inflexible substrate can have a certain degree of flexibility, e.g. a glass plate having a thickness of 0.5 mm or below, wherein the flexibility of the substantially inflexible substrate is small in comparison to the flexible substrates. According to embodiments described herein, the substrate may be made of any material suitable for material deposition. For instance, the substrate may be made of a material selected from the group consisting of glass (for instance soda-lime glass, borosilicate glass etc.), metal, polymer, ceramic, compound materials, carbon fiber materials or any other material or combination of materials which can be coated by a deposition process.

[0029] In the present disclosure, a “vacuum deposition chamber” is to be understood as a chamber configured for vacuum deposition. The term “vacuum”, as used herein, can be understood in the sense of a technical vacuum having a vacuum pressure of less than, for example, 10 mbar. The pressure in a vacuum chamber as described herein may be between 10⁵ mbar and about 10⁸ mbar, more particularly between 10⁵ mbar and 10⁷ mbar, and even more particularly between about 10⁶ mbar and about 10⁷ mbar. According to some embodiments, the pressure in the vacuum chamber may be considered to be either the partial pressure of the evaporated material within the vacuum chamber or the total pressure (which may approximately be the same when only the evaporated material is present as a component to be deposited in the vacuum chamber). In some embodiments, the total pressure in the vacuum chamber may range from about 1 O ⁴ mbar to about 1 O ⁷ mbar, especially in the case that a second component besides the evaporated material is present in the vacuum chamber (such as a gas or the like).

[0030] In the present disclosure, a “material deposition source” can be understood as a device or assembly configured for providing a source of material to be deposited on a substrate. In particular, a “material deposition source” may be understood as a device or assembly having a crucible configured to evaporate the material to be deposited and a distribution pipe, such as a distribution assembly configured for providing the evaporated material to the substrate. The pipe can have any shape providing an enclosure for the evaporated material having openings directing the evaporated material to a substrate. The expression “a distribution pipe configured for providing the evaporated material to the substrate” may be understood in that the distribution assembly is configured for guiding gaseous source material in a deposition direction, exemplarily indicated in FIG. 3B by arrows through the outlets 326. Accordingly, the gaseous source material, for example a material for depositing a thin film, such as a metal containing thin film, of e.g. an OLED device, is guided within the distribution pipe and exits the distribution pipe through one or more outlets 326. For example, the one or more outlets of the distribution assembly, e.g. a distribution pipe, can be nozzles extending along an evaporation direction. The evaporation direction can be essentially horizontal, e.g. the horizontal direction may correspond to the x-direction indicated in FIG. 3B.

[0031] In the present disclosure, a “crucible” can be understood as a device having a reservoir for the material to be evaporated by heating the crucible. Accordingly, a “crucible” can be understood as a source material reservoir which can be heated to vaporize the source material into a gas by at least one of evaporation and sublimation of the source material. The crucible includes a heater to vaporize the source material in the crucible into a gaseous source material. The reservoir can have an inner volume for receiving the source material to be evaporated, e.g. a metal material. For example, the volume of the crucible can be between 100 cm³ and 4000 cm³, particularly between 1000 cm³ and 3000 cm³, more particularly 2800 cm³. In particular, the crucible may include a heating unit configured for heating the source material provided in the inner volume of the crucible up to a temperature at which the source material evaporates. For instance, the crucible may be a crucible for evaporating metal materials, e.g. metal materials having an evaporation temperature of above 800°C.

[0032] The distribution assembly or the distribution pipe can be a linear distribution showerhead, for example, having a plurality of openings (or an elongated slit) disposed therein. A showerhead as understood herein can have an enclosure, hollow space, or pipe, in which the evaporated material can be provided or guided, for example from the evaporation crucible to the substrate. According to embodiments which can be combined with any other embodiments described herein, the length of the distribution pipe may correspond at least to the height of the substrate to be deposited. In particular, the length of the distribution pipe may be longer than the height of the substrate to be deposited, at least by 10% or even 20%. For example, the length of the distribution pipe can be 1.3 m or above, for example 2.5 m or above. Accordingly, a uniform deposition at the upper end of the substrate and/or the lower end of the substrate can be provided. According to an alternative configuration, the distribution pipe or a distribution assembly may include one or more point sources which can be arranged along a vertical axis.

[0033] Accordingly, a “distribution pipe” or the “distribution assembly” as described herein may be configured to provide a line source extending essentially vertically. In the present disclosure, the term “essentially vertically” is understood particularly when referring to the substrate orientation, to allow for a deviation from the vertical direction of 10° or below. This deviation can be provided because a substrate support with some deviation from the vertical orientation might result in a more stable substrate position or may result in less particles on the substrate during substrate processing. Yet, the substrate orientation during deposition of the metal material is considered essentially vertical, which is considered different from the horizontal substrate orientation. Accordingly, the surface of the substrates can be coated by a line source extending in one direction corresponding to one substrate dimension and a translational movement along the other direction corresponding to the other substrate dimension.

[0034] Embodiments of the present disclosure relate to an evaporation source including an evaporation tube or an evaporation pipe and including a crucible. According to some embodiments, which can be combined with other embodiments described herein, the sealing concept, i.e. a flange of a crucible and/or a corresponding flange of a distribution pipe, is provided. The sealing concept is particularly useful for high temperatures of 800°C or above, for example, 1000°C to 1500°C or even 1200°C to 1500°C. The sealing surface includes a ball cut, i.e. two or more spheroid surfaces. A ball cut sealing for high temperature metal evaporation sources is provided.

[0035] According to an embodiment, a crucible to evaporate a material is provided. The crucible includes an enclosure to evaporate the material and a flange coupled to the enclosure for providing a sealing surface of the crucible. The sealing surface includes a first spheroid surface having a portion of a first spheroid and a second spheroid surface having a portion of a second spheroid, wherein the second spheroid is different from the first spheroid. According to some embodiments, the sealing surface is self-sealing, i.e. a separate seal can be avoided.

[0036] With exemplary reference to FIGS. 1 A and IB, according to embodiments which can be combined with any other embodiment described herein, the at least one material deposition source may include a crucible compartment 115 having a closable opening 116 configured for exchanging the crucible. Such a configuration can in particular be beneficial for facilitated maintenance as well as for facilitated and quick crucible exchange or replacement. The crucible holding arrangement may include a heating arrangement 160 configured to provide heat to the crucible for evaporating the material. In particular, as exemplarily shown in FIGS. 1A and IB, the heating arrangement 160 can be configured such that at least a portion of the crucible can be placed inside the heating arrangement. For example, the heating arrangement may be configured for holding or supporting the crucible in a lateral direction. The heating arrangement can be configured for providing heat to the crucible for evaporating metal materials, e.g. metal materials having an evaporation temperature of about 800°C to about 1600°C, provided inside the crucible.

[0037] According to some embodiments, which can be combined with other embodiments described herein, the crucible, and optionally components of the crucible compartment, can include a refractory metal, for example, Mo, W, Ta and alloys or composites thereof. For example, MoLa may be used. Accordingly, high temperatures can be provided during operation of the crucible. [0038] Accordingly, according to embodiments which can be combined with any other embodiment described herein, an actuator 130 can be provided to press the crucible towards the distribution pipe 120. The actuator can include at least one element of a spring and a pneumatic actuator. [0039] As shown in FIG. 1A, according to embodiments which can be combined with any other embodiment described herein, the connection between the crucible 110 and the distribution pipe may be provided by a counterpart sealing surface 112A of the distribution pipe and a sealing surface 112B of the crucible. For instance, as exemplarily shown in FIG. 1 A, the counterpart sealing surface 112A can be a concave contact surface and the sealing surface 112B may be a mating convex contact surface.

[0040] As exemplarily shown in FIG. IB, according to embodiments which can be combined with any other embodiment described herein, the actuator 130 may be connected to the crucible holding arrangement 140. For instance, the crucible holding arrangement 140 may include a mounting assembly 141 configured for mounting the crucible holding arrangement to the wall of the at least one material deposition source, as exemplarily shown in FIG. IB. In particular, the mounting assembly 141 can include a mounting plate 142 and one or more fixation elements 143, such as a screw. The wall 111 of the material deposition source to which the holding arrangement is mountable can include corresponding receptions for the one or more fixation elements 143.

[0041] FIGS. 2A and 2B show the crucible 110 and the distribution pipe 120. The crucible has a flange. The distribution pipe has a counterpart flange, particularly a corresponding counterpart flange. The flange of the crucible includes a sealing surface 112B. The counterpart flange of the distribution pipe includes the counterpart sealing surface 112A. The sealing surface is a spheroid surface 212 or can include a spheroid surface 212. The counterpart sealing surface is a counterpart spheroid surface or can include counterpart spheroid surface.

[0042] The spheroid surface of the crucible is rotational symmetric about an axis of circular symmetry, for example, a vertical axis in figs. 2A and 2B. The height of the spheroid surface is referred to herein as a second height 264. The height of the counterpart spheroid surface is referred herein as the first height 262. Further, the flange of the crucible includes an opening having an opening size 254. The opening is configured for trespassing of material evaporated in the crucible 110 towards the distribution pipe 120. The opening size 254 of the flange of the crucible, for example, a diameter of the opening is larger than the second height 264. Further, flange of the distribution pipe may include an opening having an opening size 252.

[0043] The counterpart spheroid surface of the distribution pipe is rotational symmetric, particularly around the same axis of circular symmetry as the crucible. The first height 262 of the counterpart spheroid surface is larger than the second height 264 of the spheroid surface. According to some embodiments, which can be combined with other embodiments described herein, the second height can be different by at least 20% relative to the first height. For example, for a first height of 10 mm, the second height can be 8 mm or below or the second height can be 12 mm or above.

[0044] The flange of the crucible 110 shown in fig. 2B further includes a further spheroid surface 214. The spheroid surface 212 is a portion of a first spheroid and the further spheroid surface 214 is a portion of the second spheroid. The second spheroid is different from the first spheroid. Particularly, the radius of the first spheroid along a semi axis of the spheroid is different from the radius of the second spheroid along the semi axis, i.e. the same semi axis. Accordingly, a step can be provided as shown in fig. 2B and in more detail fig. 2C.

[0045] According to some embodiments, which can be combined with other embodiments described herein, a spheroid or a spheroid surface as referred to herein is understood as a quadratic surface obtained by rotating an ellipse. For example, the spheroid can be a flattened spheroid or an oblate spheroid. According to some embodiments, which can be combined with other embodiments described herein, the spheroid can be sphere.

[0046] According to an embodiment, a crucible to evaporate a material is provided. The crucible includes an enclosure to evaporate the material and a flange coupled to the enclosure. The flange includes a spheroid surface being rotational symmetric about an axis of circular symmetry, the spheroid surface having a second height along the axis and an opening for trespassing of evaporated material having an opening size, wherein the second height is 30% or less relative to the opening size. For example, for an opening size of 100 mm, the second height can be 30 mm or less.

[0047] The embodiments described with respect to figs. 2A and 2B refer to the crucible flange having a smaller height at the sealing surface as compared to a distribution pipe flange having a larger hide of the sealing surface. According to some embodiments, which can be combined with other embodiments described herein, the roles of the sealing surface and the counterpart sealing surface can be exchanged.

Further, the crucible is described with the convex sealing surface and the distribution pipe is described with a concave sealing surface. According to some embodiments, which can be combined with other embodiments described herein, the further roles of the sealing surface and the counterpart sealing surface can be exchanged. Features details and implementation described the present disclosure may similarly apply to the exchanged roles and/or the exchanged further roles.

[0048] Embodiments of the present disclosure are particularly configured for high temperature applications, for example, evaporation of metals having an evaporation temperature of 800°C or above. Accordingly, the sealing surface and the counterpart sealing surface experience a large temperature range during heating from room temperature to the evaporation temperature. Accordingly, providing one sealing surface or one spheroid surface having a comparable small height, for example, relative to the height of the opposite sealing surface or the opposite spheroid surface is advantageous during thermal expansion. Particularly, small tilting movements have a reduced or no impact on the sealing characteristics of the flange and the counterpart flange. Advantageously, a seal for high temperature applications can be provided. Additionally or alternatively, a comparable small height of the spheroid surface relative to the opening diameter can be provided

[0049] FIG. 2C shows a further flange 200 of a crucible, for example, a crucible as shown in FIGS. 1A and IB. FIG. 2C corresponds to crucible shown in fig. 2B, wherein a step is provided. FIG. 2C illustrates an optional implementation of a spheroid surface, i.e. a spheroid sealing surface having a comparable small height. The flange includes the sealing surface 112B. The sealing surface includes a first spheroid surface 212, for example, a first spherical surface, having a portion of a first spheroid, for example, a first sphere. Further, a second spheroid surface 214, for example, a second spheroid surface, having a portion of a second spheroid, for example, a second sphere can be provided. According to some embodiments, which can be combined with other embodiments described herein, the second spheroid surface may provide the guiding surface, for example, the surface for improved alignment of the crucible relative to the distribution pipe. Additionally or alternatively, particularly for small step sizes, the second spheroid surface may provide a sealing property, and may, thus, be a portion of the sealing surface.

[0050] The first spheroid and the second spheroid are different. For example, the first spheroid can have a radius of a semi axis of the spheroid different from the second spheroid. A step can be provided between the first spheroid and the second spheroid by the different radius. The step may extend along a perimeter, i.e. a circle, of the flange.

[0051 ] Common vacuum sealing concepts like ConFlat (CF) or Klein Flange (KF) are not suitable for high temperatures. In particular, common sealing materials are not suitable for high temperatures. According to embodiments of the present disclosure, metal surfaces are utilized for sealing. At least one of a sealing surface and a counterpart sealing surface has a height that is smaller as the height of the other sealing surface and/or has a height, which is small as compared to the opening size of the opening for evaporated material. Optionally, at least one of the sealing surface and a counterpart sealing surface may have two different spheroid surfaces. The sealing concept according to embodiments of the present disclosure can be used for high temperatures of, for example, up to 1500°C. The flange is configured for temperatures of 800°C or above.

[0052] According to some embodiments, which can be combined with other embodiments described herein, the sealing surface includes a refractory metal, particularly, Mo, W, Ta, alloys or composites. For example, MoLa may be used. Yet further, additionally or alternatively, the sealing surface has a roughness of Rz = 3.0 or below, particularly Rz = 2.5 or below.

[0053] FIG. 2C shows a flange of the crucible having a first spheroid surface and a second spheroid surface. A similar concept may be applied to a counterpart sealing surface of distribution pipe. According to an embodiment, a distribution pipe for directing evaporated material in a vacuum processing system is provided. The distribution pipe includes a distribution housing having one or more openings for directing the evaporated material and a counterpart flange coupled to the distribution housing. The counterpart flange includes a counterpart spheroid surface being rotational symmetric about an axis of circular symmetry. The counterpart spheroid surface has a second counterpart height along the axis. The counterpart flange includes an counterpart opening for trespassing of evaporated material having an counterpart opening size, wherein the second counterpart height is 30% or less than the counterpart opening size. According to some embodiments, which can be combined with other embodiments described herein, the design of the sealing surface as described with respect to FIG. 2C, may alternatively be provided for the counterpart sealing surface. For example, the first counterpart spheroid or counterpart sphere can have a radius different from the second counterpart spheroid the second counterpart sphere. A step can be provided between the first counterpart spheroid and the second counterpart spheroid.

[0054] Embodiments of a material deposition assembly are described with respect to FIGS. 3 A and 3B. According to an embodiment, a material deposition assembly for depositing a material on a substrate in a vacuum deposition chamber is provided. The material deposition assembly 300 is exemplarily shown in FIG. 3B. At least one material deposition source 305 is provided. The material deposition source includes a distribution pipe 120 configured for directing the evaporated material to the substrate, wherein the distribution pipe has a counterpart flange with at least a first counterpart spheroid surface. Further, a crucible according to any of the embodiments described herein to evaporate the material is provided. [0055] FIG. 3A shows actuators 130. A material deposition assembly can include at least one actuator to provide a contact force at a connection between the flange, for example, the flange of the crucible and the counterpart flange, for example, the flange at the distribution pipe. In light of the heat load at the very high temperatures, a temperature-resistant pricing mechanism for the sealing is beneficial. An actuator can include the spring 330 in a housing 332. The housing can reduce the heat radiation to the spring 330. According to some embodiments, which can be combined with other embodiments described herein, a pneumatic actuator may be used instead of the spring. Guiding pins 340 transfer the force of the actuator from a remote location to the crucible. For example, guiding pins can be utilized to contact the mounting plate 142 supporting the crucible 110. According to some embodiments, which can be combined with other embodiments described herein, one or more point contacts 342 can be provided. The point contacts reduce heat transfer between the crucible 110 and the mechanism providing a force of the actuator, for example, a spring.

[0056] FIG. 3B shows the crucible 110 being engaged with the distribution pipe 120. The actuator is provided to contact force Fc for the connection between the flange and the counterpart flange. According to some embodiments, the spheroid surface can be a convex contact surface and the counterpart spheroid surface can be a concave contact surface. As shown in FIG. 3 A, the actuator can be coupled to the crucible via pins to provide the actuator outside the crucible housing, for example, the crucible compartment 115 shown in FIG. 1 A.

[0057] According to some embodiments, which can be combined with other embodiments described herein, the sealing concept having ball cut sealing surfaces is self-centering. The sealing is not affected by strain and/or bending during source heat up and is insensitive to small misalignments, particularly in light of the small height of one of the spheroid surfaces engaging with each other. The sealing function can be maintained at high temperatures, and particularly in the absence of an extra sealing element, such as the seal that may need to be exchanged during maintenance.

[0058] The sealing surfaces have a high temperature stable metal material, for example including Mo, Ta, W, alloys thereof or combinations or compositions thereof. The two mating sealing surfaces have a ball cut shape (male and female) and are pressed together by a pressing mechanism such as the actuator 130. A pneumatic pressing mechanism may also enable detaching of the sealing surfaces (e.g. crucible and tube) in a hot state.

[0059] According to some embodiments, which can be combined with other embodiments described herein, the contact area of two counterparts is reduced to an spherical segment or spherical zone, see for example surface 212 in FIG. 2C to ensure good self-centering and to avoid clamping and/or bonding of the two components of the evaporation source. Similarly, a spheroid segment or spheroid zone may be provided. A vacuum evaporator with a sealing concept for high-temperature sealing can be provided. The crucible is detachable for refilling of material to be evaporated during maintenance.

[0060] FIG. 3B shows a schematic sectional view of a material deposition assembly 300 according to embodiments described herein. In particular, the material deposition assembly is configured for depositing a material on a substrate in a vacuum deposition chamber. As exemplarily shown in FIG. 3B, the material deposition assembly includes at least one material deposition source 305 having a crucible 110 configured to evaporate the material. Further, the material deposition assembly includes a distribution pipe 120 configured for providing the evaporated material to the substrate. As exemplarily shown in FIG. 3B, the distribution pipe 120 of the at least one deposition source may include a distribution pipe with one or more outlets 326 provided along the length of the distribution pipe.

[0061] An opening 313 may be provided at the bottom of the distribution pipe 120. For instance, the opening 313 provided at the bottom of the distribution pipe 120 can be arranged and configured to allow fluid communication with the crucible 110, for instance via an opening provided in a top wall of the crucible. For example, the diameter D of the opening can be selected from a range having a lower limit of D = 10 mm, particularly a lower limit of D = 15 mm, more particularly a lower limit of D = 20, and an upper limit of D = 100 mm, particularly an upper limit of D = 80 mm, more particularly an upper limit of D = 50 mm. [0062] Further, as exemplarily shown in FIGS. 3 A and 3B, the material deposition assembly 300 may include an actuator 130 configured for applying a contact force F_c at a connection 312 between the crucible 110 and the distribution pipe 120. As exemplarily indicated with the arrow in FIG. 3B, the force applicator or actuator is configured for applying a force F in a direction towards a connection 312 between the crucible 110 and the distribution pipe 120. For instance, the force F can be a force in a substantially vertical direction, e.g. in a direction opposite to the gravitational force. For instance, the actuator 130 can be configured to provide a force of 100 N, e.g. a contact force at a connection between the crucible and the distribution pipe.

[0063] According to embodiments which can be combined with other embodiments described herein, the at least one material deposition source may include at least a first deposition source 305 A and a second deposition source 305B. Additionally, a third deposition source 305C may be provided, as exemplarily shown in FIG. 4. The first deposition source 305A includes a first crucible 110A configured to evaporate a first material, a first distribution pipe 120 A configured for providing the first evaporated material to the substrate, and a first actuator 130A configured for applying a contact force at a connection between the first crucible 110A and the first distribution pipe 120A. The second deposition source 305B includes a second crucible 110B configured to evaporate a second material, a second distribution pipe 120B configured for providing the second evaporated material to the substrate, and a second actuator 130B configured for applying a contact force at a connection between the second crucible 110B and the second distribution pipe 120B. The third deposition source 305C includes a third crucible 1 IOC configured to evaporate a third material, a third distribution pipe 120C configured for providing the third evaporated material to the substrate, and a third actuator 130C configured for applying a contact force at a connection between the third crucible 1 IOC and the third distribution pipe 120C.

[0064] FIG. 5 shows a more detailed schematic cross-sectional top view of a material deposition assembly according to further embodiments described herein as exemplarily shown in FIG. 4. In particular, FIG. 5 shows a cross-sectional top view of a material deposition assembly including a first deposition source 305 A, a second deposition source 305B, and a third deposition source 305C.

[0065] Accordingly, from FIGS. 4 and 5, it is to be understood that three distribution assemblies, e.g. distribution pipes, and corresponding evaporation crucibles can be provided next to each other. Accordingly, a material deposition assembly may be provided as an evaporation source array, e.g. wherein more than one kind of material can be evaporated at the same time. In particular, with exemplary reference to FIG. 5, the at least one material deposition source of the material deposition assembly 300 may include three deposition sources, e.g. a first deposition source 305A, a second deposition source 305B, and a third deposition source 305C. Each deposition source can include a distribution pipe as described herein and a crucible as described herein, wherein a sealing surface and a counterpart sealing surface is provided. At least one of the sealing surface and the counterpart sealing surface is provided according to embodiments of the present disclosure, i.e. having a height smaller than the engaging sealing surface or a height being 30% or less relative to an opening size or opening diameter of an opening in the flange, wherein the opening is for trespassing of the evaporated material.

[0066] It is to be understood that the description with respect to the features of the at least one material deposition source 305 as described with reference to FIGS. 1-3B, may also be applied to the first deposition source 305 A, the second deposition source 305B and the third deposition source 305C.

[0067] According to embodiments which can be combined with any other embodiment described herein, an evaporator control housing 580 may be provided adjacent to the least one material deposition source, e.g. having a first distribution pipe 120A, a second distribution pipe 120B, and a third distribution pipe 120C, as exemplarily shown in FIG. 5. In particular, the evaporator control housing can be configured to maintain atmospheric pressure therein and is configured to house at least one element selected from the group consisting of: a switch, a valve, a controller, a cooling unit, a cooling control unit, a heating control unit, a power supply, and a measurement device. [0068] In FIG. 5, for illustrative purposes, evaporated source material exiting the outlets of the distribution assemblies are indicated by arrows. Due to the essentially triangular shape of the distribution assemblies, the evaporation cones originating from the three distribution assemblies are in close proximity to each other, such that mixing of the source material from the different distribution assemblies can be improved. In particular, the shape of the cross-section of the distribution pipes allows to place the outlets or nozzles of neighboring distribution pipes close to each other.

[0069] According to an aspect of the present disclosure, a vacuum deposition system 600 is provided, as exemplarily shown in FIG. 6. The vacuum deposition system includes a vacuum deposition chamber 610, a material deposition assembly 300 according to any of the embodiments described herein in the vacuum deposition chamber 610, and a substrate support configured for supporting a substrate 601 during material deposition.

[0070] In particular, the material deposition assembly 300 can be provided on a track or linear guide 622, as exemplarily shown in FIG. 6. The linear guide 622 may be configured for the translational movement of the material deposition assembly 300. Further, a drive for providing a translational movement of material deposition assembly 300 can be provided. In particular, a transportation apparatus for contactless transportation of the material deposition assembly source may be provided in the vacuum deposition chamber. As exemplarily shown in FIG. 6, the vacuum deposition chamber 610 may have a gate valves 615 via which the vacuum deposition chamber can be connected to an adjacent routing module. The routing module can be configured to transport the substrate to a further vacuum deposition system for further processing. [0071] With exemplary reference to FIG. 6, according to embodiments which can be combined with any other embodiment described herein, two substrates, e.g. a first substrate 601A and a second substrate 601B, can be supported on respective transportation tracks within the vacuum deposition chamber 610. Further, two tracks for providing masks 633 thereon can be provided. [0072] With exemplary reference to FIG. 6, a source support 631 configured for the translational movement of the material deposition assembly 300 along the linear guide 622 may be provided. The source support 631 supports a crucible 110 and a distribution pipe 120 provided over the evaporation crucible, as schematically shown in FIG. 6. Accordingly, the vapor generated in the evaporation crucible can move upwardly and out of the one or more outlets of the distribution pipe. Accordingly, as described herein, the distribution pipe is configured for providing evaporated material, particularly a plume of evaporated metal material, from the distribution pipe 120 to the substrate 601.

[0073] According to an embodiment, a vacuum deposition system is provided. The vacuum deposition system includes a vacuum deposition chamber and a material deposition assembly according to any of the embodiments described herein. Particularly, a flange with a sealing surface according to embodiments described herein is provided. A substrate support is configured for supporting a substrate during material deposition, particularly in an essentially vertical orientation.

[0074] According to an embodiment, as shown in FIG. 7, a method 700 of manufacturing a device having at least one metallic layer with a material deposition assembly is provided. The material deposition assembly includes at least one material deposition source with a crucible according to embodiments described herein and a distribution pipe. The method includes, according to operation 710, inserting the crucible into a compartment of the at least one material deposition source. At operation 720, a contact force at a connection between the crucible and the distribution pipe is applied. At operation 730, a metal to deposit the at least one metallic layer is evaporated.

[0075] Thus, in view of the embodiments described herein, an improved material deposition assembly and an improved vacuum deposition system are provided, particularly for high temperature evaporation applications, e.g. during OLED device manufacturing. The sealing concept as described herein, which is applicable for high- temperature sealing of an evaporation crucible, may also be utilized in applications of material deposition on flexible substrates, i.e. WEBs, or for material deposition on wafers, e.g. for semiconductor manufacturing.

[0076] While the foregoing is directed to embodiments of the disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. [0077] In particular, this written description uses examples to disclose the disclosure, including the best mode, and also to enable any person skilled in the art to practice the described subject-matter, including making and using any devices or systems and performing any incorporated methods. While various specific embodiments have been disclosed in the foregoing, mutually non-exclusive features of the embodiments described above may be combined with each other. The patentable scope is defined by the claims, and other examples are intended to be within the scope of the claims if the claims have structural elements that do not differ from the literal language of the claims, or if the claims include equivalent structural elements with insubstantial differences from the literal language of the claims.

Claims

1. A material deposition assembly for depositing a material on a substrate in a vacuum deposition chamber, comprising: at least one material deposition source comprising: a distribution pipe configured for directing evaporated material to the substrate, the distribution pipe having a counterpart flange with a counterpart spheroid surface being rotational symmetric about an axis of circular symmetry, the counterpart spheroid surface having a first height along the axis; and a crucible to evaporate the material, the crucible having a flange with a spheroid surface being rotational symmetric about the axis, the spheroid surface having a second height along the axis, wherein the second height is different from the first height, particularly the second height is different by at least 20% relative to the first height.

2. The material deposition assembly according to claim 1, the flange further comprising: an opening for trespassing of evaporated material having an opening size, wherein the second height is 30% or less than the opening size.

3. The material deposition assembly according to any of claims 1 to 2, further comprising: an actuator to provide a contact force at a connection between the flange and the counterpart flange.

4. The material deposition assembly according to any of claims 1 to 3, wherein the actuator comprises at least one element of a spring or a pneumatic actuator.

5. The material deposition assembly according to any of 1 to 4, wherein the spheroid surface is a convex contact surface and wherein the counterpart spheroid surface is a concave contact surface, particularly configured to engage with the convex contact surface.

6. The material deposition assembly according to any of claims 1 to 5, wherein the actuator is coupled to the crucible via pins to provide the actuator outside a crucible housing.

7. A crucible to evaporate a material, comprising: an enclosure to evaporate the material; a flange coupled to the enclosure, the flange comprising: a spheroid surface being rotational symmetric about an axis of circular symmetry, the spheroid surface having a second height along the axis; and an opening for trespassing of evaporated material having an opening size, wherein the second height is 30% or less relative to the opening size.

8. The crucible according to claim 7, wherein the spheroid surface is a portion of a first spheroid, and wherein the flange further comprises: a further spheroid surface having a portion of a second spheroid, the second spheroid being different from the first spheroid.

9. The crucible according to claim 8, wherein the first spheroid has a first radius along a semi-axis different from a second radius along the semi-axis of the second spheroid.

10. The crucible according to any of claims 8 to 9, wherein a step is provided between the first spheroid and the second spheroid.

11. The crucible according to any of claims 7 to 10, wherein the spheroid surface comprises a refractory metal, particularly, Mo, W, Ta, alloys or composites thereof.

12. The crucible according to any of claims 7 to 11, wherein the spheroid surface has a roughness of Rz = 3.0 or below, particularly Rz = 2.5 or below.

13. The crucible according to any of claims 7 to 12, wherein the flange is configured for temperatures of 800 °C or above.

14. A distribution pipe for directing evaporated material in a vacuum processing system, comprising: a distribution housing having one or more openings for directing the evaporated material; and a counterpart flange coupled to the distribution housing, the counterpart flange comprising: a counterpart spheroid surface being rotational symmetric about an axis of circular symmetry, the counterpart spheroid surface having a second counterpart height along the axis, and an counterpart opening for trespassing of evaporated material having an counterpart opening size, wherein the second counterpart height is 30% or less than the counterpart opening size.

15. A vacuum deposition system, comprising: a vacuum deposition chamber; a material deposition assembly according to any of claims 1 to 6 in the vacuum deposition chamber; and a substrate support configured for supporting the substrate during material deposition.

16. A method of manufacturing a device having at least one metallic layer with a material deposition assembly having at least one material deposition source with a crucible according to any of claims 7 to 13 and a distribution pipe, the method comprising: inserting the crucible into a compartment of the at least one material deposition source; applying a contact force at a connection between the crucible and the distribution pipe; and evaporating a metal to deposit the at least one metallic layer.