Method and apparatus for manufacturing pixels on a substrate

Abstract

A method of manufacturing pixels on a substrate (10) includes guiding an evaporated source material through a plurality of nozzles (22) of an evaporation source (20), each of the nozzles generating a plume (318) of evaporated source material propagating towards the substrate. The method includes individually shaping the plumes using a plurality of shaping apertures (33). Each shaping aperture has an aperture shape and an aperture orientation. A portion of the plumes passes through a plurality of pixel openings (490) of a mask structure to deposit a pixel pattern including a plurality of pixel layers (410) on the substrate. Each pixel opening (490) has a pixel opening shape and a pixel opening orientation. At least one of the aperture shape and the aperture orientation of the shaping apertures is adapted to at least one of the pixel opening shape and the pixel opening orientation of the pixel openings.

Description

METHOD AND APPARATUS FOR MANUFACTURING PIXELS ON A SUBSTRATETECHNICAL FIELD

[0001] Embodiments of the present disclosure relate to the deposition of materials on a substrate and to apparatuses for depositing materials on a substrate. Embodiments of the present disclosure particularly relate to apparatuses having an evaporation source for depositing evaporated materials, e.g. organic materials, on a substrate. Embodiments of the present disclosure more particularly relate to apparatuses for manufacturing pixels, e.g. OLED pixels, on a substrate. Further embodiments relate to methods of depositing material, e.g. organic material, on a substrate.BACKGROUND

[0002] Organic evaporators are a tool for the production of organic light-emitting diodes (OLEDs). OLEDs are a special type of light-emitting diode in which the emissive layer comprises a thin-film of certain organic compounds. OLEDs are used in the manufacture of television screens, computer monitors, mobile phones and other hand-held devices for displaying information. OLEDs can also be used for general space illumination. The range of colors, brightness, and viewing angles possible with OLED displays are greater than that of traditional LCD displays because OLED pixels directly emit light and do not need a back light. Therefore, the energy consumption of OLED displays is considerably less than that of traditional LCD displays. Further, the fact that OLEDs can be manufactured onto flexible substrates results in further applications. An OLED display, for example, may include layers of organic material situated between two electrodes that are all deposited on a substrate in a manner to form a matrix display panel having individually energizable pixels. The OLED is generally placed between two glasspanels, and the edges of the glass panels are sealed to encapsulate the OLED therein.

[0003] There are many challenges encountered in the manufacture of such display devices. OLED displays or OLED lighting applications include a stack of several organic materials, which are for example evaporated in a vacuum. The organic materials may be deposited through shadow masks. For the fabrication of OLED stacks with high efficiency, the co-deposition or co-evaporation of two or more materials, e.g. host and dopant, leading to mixed / doped layers is beneficial. Further, it has to be considered that there are several process conditions for the evaporation of the very sensitive organic materials.

[0004] For depositing the material on a substrate, the material is heated until the material evaporates. Distribution pipes guide the evaporated material to the substrates through nozzles. In recent years, the precision of the deposition process has increased, e.g. allowing for smaller and smaller pixel sizes. In some processes, masks are used for defining the pixels when the evaporated material passes through the mask openings. However, shadowing effects of a mask, the spread of the evaporated material and the like make it difficult to further increase the precision and the predictability of the evaporation process.

[0005] In view of the above, an increased precision and predictability of evaporation processes for manufacturing devices having a high quality and precision is beneficial.SUMMARY

[0006] According to an embodiment, a method of manufacturing pixels on a substrate is provided. The method includes guiding an evaporated source material through a plurality of nozzles of an evaporation source, each of the plurality of nozzles generating a plume of evaporated source material propagating towards the substrate. The method includes individually shaping the plumes of evaporated source material using a plurality of shaping apertures. Each shaping aperture of the plurality of shaping apertures has an aperture shape and an aperture orientation. Aportion of the plumes of evaporated source material passes through a plurality of pixel openings of a mask structure to deposit a pixel pattern including a plurality of pixel layers on the substrate. Each pixel opening of the plurality of pixel openings has a pixel opening shape and a pixel opening orientation. At least one of the aperture shape and the aperture orientation of the plurality of shaping apertures is adapted to at least one of the pixel opening shape and the pixel opening orientation of the plurality of pixel openings.

[0007] According to a further embodiment, a method of manufacturing pixels on substrates is provided.

[0008] The method includes performing a first deposition process. The first deposition process includes guiding an evaporated source material through a first plurality of nozzles, each of the first plurality of nozzles generating a plume of evaporated source material propagating towards a first substrate. The first deposition process includes individually shaping the plumes of evaporated source material using a first plurality of shaping apertures, each of the shaping apertures of the first plurality of shaping apertures having a first aperture shape and a first aperture orientation. A portion of the plumes of evaporated source material passes through a first plurality of pixel openings of a first mask structure to deposit a first pixel pattern including a first plurality of pixel layers on the first substrate. Each pixel opening of the first plurality of pixel openings has a first pixel opening shape and a first pixel opening orientation.

[0009] The method includes performing a second deposition process. The second deposition process includes guiding an evaporated source material through a second plurality of nozzles, each of the second plurality of nozzles generating a plume of evaporated source material propagating towards a second substrate. The second plurality of nozzles is equal to, or different from, the first plurality of nozzles. The second substrate is equal to, or different from, the first substrate. The second deposition process includes individually shaping the plumes of evaporated source material using a second plurality of shaping apertures, each of the shaping apertures of the second plurality of shaping apertures having a second aperture shape and a second aperture orientation. The second aperture shape is differentfrom the first aperture shape and / or the second aperture orientation is different from the first aperture orientation. A portion of the plumes of evaporated source material passes through a second plurality of pixel openings of a second mask structure to deposit a second pixel pattern including a second plurality of pixel layers on the second substrate, each pixel opening of the second plurality of pixel openings having a second pixel opening shape and a second pixel opening orientation. The second pixel opening shape is different from the first pixel opening shape and / or the second pixel opening orientation is different from the first pixel opening orientation.

[0010] According to a further embodiment, an apparatus for manufacturing pixels on a substrate is provided. The apparatus includes a substrate support. The apparatus includes an evaporation source for guiding an evaporated source material through a plurality of nozzles of the evaporation source, each of the plurality of nozzles configured to generate a plume of evaporated source material propagating towards the substrate supported by the substrate support. The evaporation source includes a plurality of shaping apertures to individually shape the plumes of evaporated source material, each shaping aperture of the plurality of shaping apertures having an aperture shape and an aperture orientation. The apparatus is configured such that a portion of the plumes of evaporated source material passes through a plurality of pixel openings of a mask structure to deposit a pixel pattern including a plurality of pixel layers on the substrate, each pixel opening of the plurality of pixel openings having a pixel opening shape and a pixel opening orientation. At least one of the aperture shape and the aperture orientation of the plurality of shaping apertures is adapted to at least one of the pixel opening shape and the pixel opening orientation of the plurality of pixel openings.

[0011] Further aspects, advantages and features of the present disclosure are apparent from the description and the accompanying drawings.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 present disclosure, briefly summarized above, may be had by reference to embodiments.The accompanying drawings relate to embodiments of the present disclosure and are described in the following:FIG. 1 shows a schematic top view of a deposition apparatus including an evaporation source;FIGs. 2A-C show schematic views of portions of an evaporation source;FIG. 3 shows a schematic top view of an evaporation source;FIG. 4A illustrates the deposition of a pixel layer on a substrate;FIG. 4B illustrates pixel layers having different shapes and orientations;FIGs. 5-8 show substrates having pixel layers with different shapes and orientations;FIGs. 9-12 show mask structures having pixel openings with different shapes and orientations;FIGs. 13-16 show shaping apertures of an evaporation source having different shapes and orientations;FIG. 17 illustrates a deposition process for depositing a pixel layer on a substrate using a mask structure;FIGs. 18-21 illustrate the effect of the shape and the orientation of a shaping aperture in a deposition process for depositing a pixel layer on a substrate.DETAILED DESCRIPTION

[0013] Reference will now be made in detail to the various embodiments of the present disclosure, one or more examples of which are illustrated in the figures. Within the following description of the drawings, the same reference numbers refer to the same components. Generally, only the differences with respect to individual embodiments are described. Each example is provided by way of explanation andis not meant as a limitation of present disclosure. Features illustrated or described as part of one embodiment can be used on, or in conjunction with, other embodiments to yield yet a further embodiment. It is intended that the description includes such modifications and variations.

[0014] Embodiments described herein relate to a deposition process involving the usage of an evaporation source having shaping apertures for shaping the plumes of evaporated material, wherein the shape and / or the orientation of the shaping apertures is tailored to the shape and / or the orientation of the pixel layers that are to be formed in the deposition process. The material utilization of the evaporated source material in the deposition process can be improved.

[0015] According to an embodiment, a method of manufacturing pixels on a substrate is provided. The method includes guiding an evaporated source material through a plurality of nozzles of an evaporation source, each of the plurality of nozzles generating a plume of evaporated source material propagating towards the substrate. The method includes individually shaping the plumes of evaporated source material using a plurality of shaping apertures. Each shaping aperture of the plurality of shaping apertures has an aperture shape and an aperture orientation. A portion of the plumes of evaporated source material passes through a plurality of pixel openings of a mask structure to deposit a pixel pattern including a plurality of pixel layers on the substrate. Each pixel opening of the plurality of pixel openings has a pixel opening shape and a pixel opening orientation. At least one of the aperture shape and the aperture orientation of the plurality of shaping apertures is adapted to at least one of the pixel opening shape and the pixel opening orientation of the plurality of pixel openings.

[0016] As used herein, the term “source material” may be understood as a material that is evaporated and deposited on a surface of a substrate. For example, in embodiments described herein, an evaporated material that is deposited on a surface of a substrate may be a source material. Non-limiting examples of materials include one or more of the following: HAT-CN, F4-TCNQ, pentacene, NPD, TPD, TAPC, mCP, rubrene, coumarin, lr(ppy)3, lr(piq)3, Alq3, CBP, bathocuproine, bathophenanthroline, Liq, LiF, Li, Ca, Yb, Cs, Mg, Ag, Al, and the like. Theevaporated source material may be an organic material, particularly an OLED material. An OLED material may be understood as an organic material suitable for the manufacture of OLEDs, e.g. including any of the aforementioned organic materials.

[0017] As used herein, the term “evaporation source” may be understood as an arrangement providing an evaporated source material to be deposited on a substrate. The evaporation source may be configured to direct an evaporated source material to be deposited on a substrate into a deposition area in a vacuum chamber, such as a vacuum deposition chamber of a deposition apparatus. The evaporated source material may be directed toward the substrate via a plurality of nozzles of the evaporation source. The nozzles may have nozzle outlets, respectively, which may be directed toward the deposition area, particularly toward the substrate to be coated.

[0018] An evaporation source may include an evaporator for evaporating the source material to be deposited on the substrate. The evaporator may be a crucible. The evaporation source may include a distribution pipe in fluid connection with the crucible. The evaporation source may include a plurality of nozzles. The distribution pipe may be configured to transport the evaporated source material to the plurality of nozzles for emitting the evaporated source material into the deposition area.

[0019] As used herein, the term “crucible” may be understood as a device or a reservoir providing or containing the source material to be deposited. The crucible may be heated for evaporating the source material to be deposited on the substrate. The crucible may be in fluid communication with the distribution pipe for transporting the evaporated source material to the distribution pipe.

[0020] As used herein, the term “distribution pipe” may be understood as a pipe for guiding and distributing the evaporated source material. The distribution pipe may guide the evaporated source material from a crucible to a plurality of nozzles in the distribution pipe. As used herein, the term “a plurality of nozzles” includes two or more nozzles. Each nozzle may include a nozzle outlet for emitting an evaporated source material towards the substrate along a main emission direction of the nozzle.The distribution pipe may be a linear distribution pipe extending in an evaporation source direction. The evaporation source direction may be a longitudinal direction of the distribution pipe. The evaporation source direction may be a vertical direction.

[0021] A distribution pipe may include a pipe having the shape of a cylinder. The cylinder may have a circular bottom shape or any other suitable bottom shape. Examples of distribution pipes will be described in more detail below. An evaporation source may include two or more distribution pipes. Each distribution pipe may be in fluid connection with a crucible of the evaporation source, such that different materials can be deposited on the substrate.

[0022] An evaporation source may include a single distribution pipe or more than one distribution pipe. A distribution pipe may include a single nozzle or more than one nozzle. A distribution pipe may include two or more nozzles, particularly ten or more nozzles.

[0023] An evaporation source may include two or more distribution pipes, wherein each distribution pipe may have a single nozzle. Alternatively, an evaporation source may include two or more distribution pipes, wherein each distribution pipe includes a plurality of nozzles. The evaporation source may include two or more distribution pipes arranged next to each other, wherein each of the two or more distribution pipes may include ten or more nozzles.

[0024] FIG. 1 shows a schematic top view of a deposition apparatus 100 including an evaporation source 20. The deposition apparatus 100 may include a vacuum chamber 110 in which the evaporation source 20 may be disposed. The evaporation source 20 may be configured for a translational movement along a surface of the substrate to be coated. For example, the evaporation source 20 may be movable in a transportation direction 102. Further, the evaporation source 20 may be configured for rotation around a rotation axis, e.g. a rotation axis extending in a direction perpendicular to the drawing plane of FIG. 1.

[0025] The evaporation source 20 may have one or more evaporation crucibles. The evaporation source 20 may have one or more distribution pipes. For instance,the evaporation source 20 shown in FIG. 1 includes two evaporation crucibles 104 and two distribution pipes 106. As is shown in FIG. 1, a substrate 10 and a further substrate 11 may be disposed in the vacuum chamber 110 for receiving the evaporated source material.

[0026] A mask structure for masking the substrate can be provided between the substrate and the evaporation source. The mask structure may have a plurality of pixel openings for allowing a pattern of pixel layers to be formed on the substrate. For example, mask structures 133 and 134 are shown in FIG. 1. As described in further detail below, a mask structure may be permanently attached to the substrate, and may in other words be part of the display. In other examples, the mask structure may be attached to the substrate in a non-permanent manner, e.g. only during the deposition process. The mask structure may be detached from the substrate after the deposition process, so that the mask structure is not part of the display. In still further examples, the mask structure may be separate from the substrate, e.g. a masking structure including a mask supported by a mask frame to hold the mask in a predetermined position.

[0027] FIG. 1 further shows a shielding device 30 for guiding the evaporated source material from the distribution pipes 106 to the substrate 10 and / or to the substrate 11, respectively, as will be explained below in more detail. The shielding device 30 may be provided downstream from the nozzles, e.g. between the distribution pipes and the substrate. The shielding device 30 may be detachably fixed to at least one distribution pipe, e.g. via screws. The material of the shielding device 30 may be adapted for evaporated source material having a temperature of about 100°C to about 1500°C. The shielding device may include, or be made of, a material having a thermal conductivity larger than 10 WZ (m K) and / or a material being chemically inert to, for instance, evaporated organic material. The shielding device may include at least one of Cu, Ta, Ti, Ni, Al, stainless steel, AIN, AI2O3, BeO, BN, SiC, DLC and graphite, or may include a coating with at least one of the named materials.

[0028] The substrate may be coated with a source material in a vertical orientation of the substrate. A distribution pipe 106 may be configured as a line sourceextending vertically. The term “vertical” is understood to allow for a deviation of 20° or below, e.g. of 10° or below, from an exact vertical direction or orientation. For example, with respect to a vertical orientation of the substrate, the mentioned deviation can be provided intentionally because a substrate support with a certain deviation from an exact vertical orientation might result in a more stable substrate position. A vertical substrate orientation during deposition of the source material is distinguished from a horizontal substrate orientation. A surface of the substrate may be coated by the evaporation source, e.g. a line source, extending in an evaporation source direction, by means of a translational movement of the evaporation source along a transportation direction. The evaporation source direction may correspond to a first substrate dimension, e.g. a height of the substrate. The transportation direction may correspond to a second substrate dimension, e.g. a width of the substrate.

[0029] The evaporation source 20 may be disposed in the vacuum chamber 110 of the deposition apparatus 100 on a track, e.g. a looped track (not shown) or linear guide 120. The track or linear guide 120 is configured for the translational movement of the evaporation source 20, e.g. in the transportation direction 102. A drive for the translational movement can be provided in the evaporation source 20, at the track or linear guide 120, within the vacuum chamber 110, or a combination thereof. The evaporation source can be moved along the surface of the substrate to be coated during deposition, particularly along a linear path. Uniformity of the deposited material on the substrate can be improved.

[0030] The deposition apparatus may be used for various applications, including applications for OLED device manufacturing.

[0031] Although FIG. 1 shows a deposition apparatus 100 with an evaporation source 20 that is movable, the embodiments described herein may also be applied to deposition systems in which the substrate is moved (e.g. along the transportation direction 102) during processing while the evaporation source is stationary. For instance, the substrates to be coated may be guided and driven along stationary material deposition arrangements.

[0032] Embodiments described herein particularly relate to deposition of organic materials, e.g. for OLED display manufacturing on large area substrates. Large area substrates or carriers supporting one or more substrates may have a size of at least 0.174 m2. For instance, the deposition system may be adapted for processing large area substrates, such as substrates of GEN 5, which corresponds to about 1.4 m2substrates (1.1 m x 1.3 m), GEN 7.5, which corresponds to about 4.3 m2substrates (1.95 m x 2.2 m), GEN 8.5, which corresponds to about 5.5 m2substrates (2.2 m x 2.5 m), or even GEN 10, which corresponds to about 8.7 m2substrates (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. Any substrate as described herein may be a large area substrate.

[0033] A substrate thickness can be from 0.1 to 1.8 mm. A holding arrangement of the deposition apparatus for holding the substrate can be adapted for such substrate thicknesses. The substrate thickness can be about 0.9 mm or below, such as 0.5 mm or 0.3 mm, and the holding arrangement may be adapted for such substrate thicknesses. The substrate may be made from any material suitable for material deposition. For instance, the substrate may be made from a material selected from the group consisting of glass (for instance non-alkali glass, 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.

[0034] FIG. 2A to FIG. 2C show parts of an evaporation source 20. As shown in FIG. 2A, the evaporation source 20 may include a distribution pipe 106. The evaporation source 20 may include evaporation crucible 104. For example, the distribution pipe can be an elongated tube extending in an evaporation source direction 204. The evaporation source 20 may include a heating unit 225. The heating unit may also be referred to as a heater. The evaporation crucible can be a reservoir for a source material, such as an organic or inorganic material to be evaporated by the heating unit 225.

[0035] A plurality of nozzles 22 may be arranged along a length direction of the evaporation source 20. The plurality of nozzles 22 may be arranged along a length direction of the distribution pipe 106.

[0036] The distribution pipe 106 may extend vertically in a length direction of the distribution pipe 106. The length direction may be the evaporation source direction 204 as described herein.

[0037] The evaporation crucible 104 may be provided at a lower end of the distribution pipe 106. The source material may be evaporated in the evaporation crucible 104. The evaporated source material may enter at a bottom portion of the distribution pipe 106 and may be guided essentially sideways through the plurality of nozzles 22 in the distribution pipe, e.g. toward an essentially vertically oriented substrate.

[0038] The plurality of nozzles 22 may be arranged such that the nozzles define a main emission direction X (see e.g. FIG. 3) that may be horizontal (where “horizontal” includes a deviation from exact horizontality by + / - 20°). The main emission direction X can be oriented slightly upward, e.g. to be in a range from exactly horizontal to 15° upward, such as 3° to 7° upward. The main emission direction may define a main direction in which evaporated source material is emitted from each nozzle of the plurality of nozzles 22.

[0039] FIG. 2B shows an enlarged schematic view of the evaporation crucible 104 and of a lower portion of the distribution pipe 106 that is to be connected to the evaporation crucible 104. The distribution pipe 106 may have an inner hollow space 210. The distribution pipe 106 may include a heating unit 215 (also called “heater”) to heat the distribution pipe. Two or more heat shields 217 may be provided around the tube of the distribution pipe 106. The heat shields are configured to reflect heat energy provided by the heating unit 215 back toward the inner hollow space 210. The energy to heat the distribution pipe 106, i.e. the energy provided to the heating unit 215, can be reduced because the heat shields 217 reduce heat losses. Heat transfer to other distribution pipes and / or to the mask or substrate can be reduced.

[0040] As shown in FIG. 2B, a plurality of nozzles 22 can be provided along a length direction of the distribution pipe 106. The distribution pipe may have more than 20 nozzles, such as 40, 50 or more nozzles arranged along a length direction of the distribution pipe. The nozzles may be spaced apart from each other. For instance, the nozzles may be spaced apart by a distance of 1 cm or more, for example, by a distance from 1 cm to 10 cm.

[0041] During operation, the distribution pipe 106 may be in fluid communication with the evaporation crucible 104. The evaporation crucible 104 may be configured to receive the source material to be evaporated and to evaporate the source material. The evaporation crucible 104 may include an outer heating unit 225 and / or one or more central heating elements 226, 228. To improve the heating efficiency of the source material within the evaporation crucible, the evaporation crucible 104 can further include a heat shield 227 configured to reflect heat energy provided by the outer heating unit 225 and, if present, by the central heating elements 226, 228, back into the enclosure of the evaporation crucible 104.

[0042] As exemplarily shown with respect to FIG. 2A and FIG. 2B, the evaporation crucible 104 may be provided at a lower side of the distribution pipe 106. According to yet further embodiments, and as illustrated in Fig. 2C, the evaporation crucible 104 may be in fluid communication with the distribution pipe via a vapor conduit 242 disposed at a central portion of the distribution pipe 106 or at another position between the lower end of the distribution pipe and the upper end of the distribution pipe.

[0043] As described herein, the distribution pipe can be a hollow cylinder. The term cylinder can be understood as commonly accepted as having a circular bottom shape and a circular upper shape and a curved surface area or shell connecting the upper circle and the lower circle. According to further additional or alternative embodiments, which can be combined with other embodiments described herein, the term cylinder can further be understood in a mathematical sense as having an arbitrary bottom shape and an identical upper shape and a curved surface area or shell connecting the upper shape and the lower shape. The cylinder does not necessarily need to have a circular cross-section.

[0044] FIG. 3 shows a schematic sectional view of an evaporation source 20. The evaporation source 20 may include a distribution pipe 106. The distribution pipe 106 may extend in a length direction (evaporation source direction 204), which may be perpendicular to the drawing plane of FIG. 3, particularly in a vertical direction. The evaporation source 20 and / or the substrate 10 may be movable in a transportation direction 102, particularly during a deposition process. A plurality of nozzles 22 may be arranged along the length direction of the distribution pipe 106. One nozzle 22 of the plurality of nozzles 22 is schematically illustrated in FIG. 3 as an outlet of the distribution pipe 106. The sectional plane of FIG. 3 intersects through the outlet of the nozzle 22. As is indicated in FIG. 3, evaporated source material may stream from the interior of the distribution pipe 106 through the outlet of the nozzle 22 toward the substrate 10. The nozzle 22 may be configured for directing a plume 318 of evaporated source material towards the substrate 10. The remaining nozzles of the plurality of nozzles 22 (not shown in FIG. 3) are likewise configured to direct a respective plume of evaporated source material toward the substrate 10.

[0045] The evaporation source 20 may include a shielding device 30. The shielding device 30 may be arranged downstream from the plurality of nozzles 22. The shielding device 30 may be configured for guiding the evaporated source material towards the substrate 10 and for individually shaping the plumes of evaporated source material. The shielding device 30 may also be referred to herein as a “shaper shield”. The shielding device may be detachably fixed to the distribution pipe 106, e.g. via fixing elements such as screws (not shown in FIG. 3).

[0046] The shielding device 30 includes a plurality of shaping apertures 33. Each shaping aperture 33 may be configured to individually shape the plume of evaporated source material emitted from a single associated nozzle 22. For example, FIG. 3 shows a shaping aperture 33 configured to individually shape the plume 318 emitted from the nozzle 22 shown in FIG. 3. It may be the case that no other plume emitted from another nozzle 22 propagates through and is shaped by the shaping aperture 33. In other words, the nozzle 22 shown in FIG. 3 may be the single associated nozzle of the shaping aperture 33 shown in FIG. 3.

[0047] Each shaping aperture of the plurality of shaping apertures 33 may be configured to individually shape a single plume of evaporated source material that is emitted from a single associated nozzle of the plurality of nozzles 22. A separate shaping aperture 33 may be arranged in front of every nozzle 22 of the plurality of nozzles. Accordingly, each plume of evaporated source material emitted from the plurality of nozzles 22 may be individually shaped by an associated shaping aperture of the plurality of shaping apertures.

[0048] Individually shaping the plumes of evaporated source material may be beneficial as compared to a shielding device with shaping apertures configured to shape more than one plume at the same time. An individual shaping of the plumes of evaporated source material may lead to increased deposition accuracy and may reduce the shadowing effect provided by a mask. For example, individually shaping the plumes of evaporated source material may lead to smaller plume opening angles and more clearly defined plume flanks. Large impact angles of the plumes on the mask and / or on the substrate can be avoided. Further, the individual plumes can be directed as appropriate.

[0049] The total number of nozzles of the evaporation source may be the same as the total number of shaping apertures. For example, ten or more shaping apertures may be arranged in front of a distribution pipe with ten or more nozzles. For example, a shielding device with thirty or more shaping apertures may be arranged in front of three distribution pipes, wherein each distribution pipe includes ten or more nozzles. Whereas in the following description reference is made to a shaping aperture 33 and a nozzle 22, i.e. the single associated nozzle of the shaping aperture 33, as shown in FIG. 3, the remaining shaping apertures of the plurality of shaping apertures may be correspondingly shaped and arranged with respect to the respective associated nozzles.

[0050] A shaping aperture 33 may be arranged in front of the associated nozzle 22, as is shown in FIG. 3. The main emission direction X of the nozzle 22 may correspond to a central axis of the shaping aperture 33. For example, the main emission direction X of the nozzle 22 may correspond to a connection line between a center of the outlet of the nozzle 22 and a center of the shaping aperture 33. Theshaping aperture 33 may be defined by a peripheral sidewall configured as a passage 43 for the plume 318. The peripheral sidewall 34 may be configured to block at least a portion of the plume 318 of evaporated source material emitted from the nozzle 22. The peripheral sidewall 34 may be configured to block an outer angular portion of the plume 318 of evaporated source material.

[0051] A shaping aperture as described herein may include an opening or a passage at least partially surrounded by a peripheral sidewall. The peripheral sidewall may be configured to shape a single plume of evaporated source material guided therethrough, particularly for limiting a maximum opening angle of the plume and for blocking an outer angular portion of the plume. In some embodiments, the passage may be entirely surrounded by the peripheral sidewall such as to shape the plume in every sectional plane which includes the main emission direction X of the associated nozzle.

[0052] As is schematically indicated in FIG. 3, the peripheral sidewall 34 may extend around the main emission direction X of the plume 318 such as to shape the perimeter of said plume. The peripheral sidewall 34 may extend parallel to the main emission direction X from a base wall 41 of the shielding device 30, wherein the base wall 41 may extend perpendicularly to the main emission direction X. The base wall 41 may have an opening 42 for the plume 318 or for an outlet of the nozzle 22 to enter the shaping aperture 33.

[0053] The shaping apertures may be arranged at a close distance to the distribution pipe 106, e.g. at a distance of 5 cm or less or 1 cm or less in the main emission direction X. Arranging the shaping apertures at a close distance downstream from the nozzles may be beneficial, because an individual shaping of the plumes may be possible even if adjacent nozzles of the plurality of nozzles are arranged at a close distance with respect to each other.

[0054] As illustrated in FIG. 3, the nozzle 22 may at least partially protrude into the shaping aperture 33. In other words, there may be a sectional plane perpendicular to the main emission direction X which intersects both the nozzle and the shaping aperture. For example, as is shown in FIG. 3, the outlet of the nozzle 22 mayprotrude into the shaping aperture 33. The nozzle 22 may protrude into an opening 42 in the base wall 41 or into the passage 43 which is surrounded by the peripheral sidewall 34. The plume 318 emitted from the nozzle 22 may be shaped directly downstream from the nozzle 22 such that an adjacent nozzle can be positioned close to the nozzle 22.

[0055] According to embodiments, each shaping aperture may be arranged at a nozzle without contacting the nozzle. It may be the case that the nozzle 22 is not in direct mechanical contact with the shaping aperture 33. For example, the nozzles 22 may protrude into the associated shaping apertures 33 at a distance from the aperture walls, as is indicated in FIG. 3. Avoiding direct contact between the nozzles and the shielding device may have the effect of a thermal decoupling between the nozzles and the shielding device. A direct thermal conduction between the typically hot nozzles and the shielding device can be avoided such that a thermal radiation toward the substrate from the shielding device can be reduced. Further, a shaping aperture that is thermally decoupled form a hot nozzle allows the shaping aperture to remain relatively cold, so that the evaporated source material emitted from the nozzle condenses more easily on the walls of the shaping aperture, thereby enhancing the shaping function of the shaping aperture.

[0056] The shielding device 30 may be actively or passively cooled. A heat flow between the cooled shielding device 30 and the nozzles can be reduced by thermally decoupling the plurality of apertures from the plurality of nozzles.

[0057] As illustrated in FIG. 3, the peripheral sidewall 34 may be configured to block the evaporated source material of the plume 318 of evaporated source material having an emission angle greater than a maximum emission angle 9 with respect to the main emission direction X in a first sectional plane.

[0058] The drawing plane of FIG. 3 illustrates the first sectional plane. The first sectional plane may include the main emission direction X. The first sectional plane may be a horizontal plane and / or a plane that extends perpendicularly to the length direction of the distribution pipe 106. As is depicted in FIG. 3, the peripheral sidewall 34 of the shaping aperture 33 may be configured to block an outer angular portionof the plume 318 of evaporated source material in the first sectional plane such that the opening angle of the emission cone is limited to an angle of 20. In other words, the peripheral sidewall 34 blocks the portion of the evaporated source material emitted by the nozzle 22 at an emission angle greater than the maximum emission angle 0. The shadowing effect due to the mask structure 133 can be reduced by reducing the maximum emission angle 0.

[0059] A distance between two adjacent nozzles 22 in the length direction of the distribution pipe 106 may be from 1 cm to 10 cm, particularly from 2 cm to 5 cm. Accordingly, the distance between two adjacent shaping apertures 33 of the plurality of shaping apertures, i.e. the distance between the respective aperture centers, may be from 1 cm to 10 cm, particularly from 2 cm to 5 cm. For example, the distance between two adjacent shaping apertures may correspond to the distance between the two adjacent associated nozzles, respectively.

[0060] Each shaping aperture 33 of the plurality of shaping apertures may have a width of 5 mm or more and / or 100 mm or less, particularly 15 mm or more and / or 50 mm or less. Therein, the width of the shaping aperture may be measured at a front end 35 of the shaping aperture which defines the maximum emission angle of the plume 318 propagating toward the substrate 10.

[0061] FIG. 4A illustrates a deposition process for depositing a pixel layer 410 on a substrate 10. In FIG. 4A, only a single pixel layer is shown for ease of presentation. It shall be understood that the discussion equally applies to a plurality of pixel layers of a pixel pattern that is deposited on the substrate 10.

[0062] A deposition process as described herein may be a dynamic deposition process including a movement of the evaporation source 20 and the substrate 10 relative to each other during deposition. Therein, either the evaporation source 20 can be moved or the substrate 10, or both. For example, during the deposition process, the evaporation source 20 may be transported in the transportation direction 102, as illustrated in FIG. 4A. Specifically, FIG. 4A illustrates four positions (a), (b), (c) and (d) of the evaporation source 20 during the deposition process, as the evaporation source 20 is transported in the transportation direction 102.

[0063] In the deposition process, an evaporated source material is guided through a plurality of nozzles 22 of the evaporation source 20. Each of the plurality of nozzles 22 generates a plume 318 of evaporated source material propagating towards the substrate. In the cross-sectional view of FIG. 4A, only a single nozzle is visible. It shall be understood that the evaporation source 20 includes a plurality of nozzles 22, which may be arranged along a length direction of the evaporation source 20, as described herein.

[0064] Each plume 318 of evaporated source material is individually shaped using a shaping aperture 33 of the evaporation source 20. The shaping aperture 33 may be defined by a peripheral sidewall 34 providing a passage for the plume 318 of evaporated source material. As illustrated schematically in FIG. 4A, the peripheral sidewall 34 blocks evaporated source material having an emission angle greater than a maximum emission angle.

[0065] A mask structure 133 having a plurality of pixel openings 490 is provided. For ease of presentation, in FIG. 4A only one pixel opening 490 is shown. It shall be understood that the discussion equally applies to any pixel opening 490 of the mask structure 133.

[0066] Not limited to the example shown in FIG. 4A, a pixel opening 490 may have a size of about 50 pm x 50 pm, or even below. A pixel opening may have a maximum dimension (e.g. a length, a width or a diameter of the pixel opening, depending on the shape of the pixel opening) of 50 pm or less, particularly 30 pm or less, more particularly 20 pm or less.

[0067] As shown in Fig. 4A, the mask structure 133 may be formed on, e.g. attached to, the substrate 10. The mask structure 133 may be permanently attached to the substrate 10. The mask structure 133 may remain attached to the substrate 10 after the deposition process is completed, and even during use of the substrate 10 in a finished product, e.g. in an OLED display. In other examples, the mask structure 133 may be non-permanently attached to the substrate 10. The mask structure 133 may be attached to the substrate 10 during the deposition process and may be detached from the substrate 10 after the deposition process, so that themask structure 133 is not part of the final display. In still further examples, the mask structure 133 may be a separate mask structure, e.g. a fine metal mask, which is not attached to the substrate 10. A separate mask structure may be used in conjunction with the substrate only for the purpose of depositing the pixel pattern.

[0068] The mask structure may include a plurality of overhang structures (with a single overhang structure being shown in FIG. 4A, yet the discussion below applies to any overhang structure). Each overhang structure may have a body portion 452 and an overhang 454 protruding from the body portion 452 at a height above the substrate 10. The overhang 454 may define a corresponding pixel opening 490 of the mask structure 133. The overhang 454 may provide a roof of the overhang structure. The overhang 454 may have a peripheral edge 456 defining the pixel opening 490. The body portion 452 may be disposed on, and may be attached to, the substrate 10. A pixel-defining layer structure 420 (PDL structure) may be disposed between the body portion 452 and the substrate 10. The PDL structure may include at least one of an organic material, such as a polyimide, and an inorganic material, such as silicon oxide, silicon nitride or silicon oxynitride, and may include multiple layers of the mentioned materials. The overhang 454 may be disposed over the body portion 452. The body portion 452 and the overhang 454 may be separate portions or may be integrally formed with each other. The body portion 452 and the overhang 454 may include, or be made of, inorganic materials.

[0069] As shown in FIG. 4A, as the evaporation source 20 moves past the pixel opening 490, a portion of the plume 318 of evaporated source material passes through the pixel opening 490 to deposit a pixel layer 410 on the substrate 10. More specifically, the pixel layer 410 may be deposited on a metal-containing layer (not shown), e.g. an indium tin oxide (ITO) layer, that may be pre-formed on the substrate and that may be configured to function as an anode of the pixel. In some examples, the metal-containing layer may be part of a metal-containing layer stack, e.g. a stack including a metal oxide layer on a metal layer (e.g. ITO on Ag).

[0070] The shaping aperture 33 determines a maximum emission angle of the plume 318 of evaporated source material. Depending on the relative position of the evaporation source 20 with respect to the substrate 10, different portions of thesubstrate 10 may be coated with the evaporated source material. For example, in position (a), only a leftmost portion of the plume 318 may reach the surface of the substrate 10, defining a rightmost boundary of a central area 412 of the pixel layer 410. In position (b), and likewise in position (c), evaporated source material may be deposited both in the central area 412 and in a peripheral area 414 (also called shadow area) of the pixel layer 410 (see also FIG. 4B, where the pixel layer 410 is depicted in a top view). In position (d), only a rightmost portion of the plume 318 may reach the surface of the substrate 10, defining a leftmost boundary of the central area 412. Accordingly, the pixel layer 410 may include a central area 412, also called major area, having a uniform thickness. The pixel layer 410 may include a peripheral area 414 having a thickness smaller than the thickness of the central area 412. The thickness of the peripheral area 414 may be non-uniform, e.g., gradually decreasing in a radially outward direction of the pixel layer 410. As shown in FIG. 4A, at least a portion of the peripheral area 414 may be deposited underneath the overhang 454. At least a portion of the peripheral area 414 may be deposited on the PDL structure 420.

[0071] The central area 412 of a pixel layer 410 may have a width (e.g. a width corresponding to the arrow 412 in FIG. 4A). The peripheral area 414 of the pixel layer 410 may surround the central area 412. The peripheral area 414 may have a width (e.g. a width corresponding to the arrow 414 in FIG. 4A). The width of the central area 412 and / or the width of the peripheral area 414 may depend on the maximum emission angle of the shaping aperture 33. Said emission angle may in turn depend on the dimensions of the peripheral sidewall 34. For example, a larger emission angle may result in a wider peripheral area414. The width of the peripheral area 414 may depend on the dimensions of the overhang 454, the body portion 452 and / or the PDL structure 420. Additionally, or alternatively, the width of the central area 412 may depend on the size of the pixel opening 490. For example, a smaller pixel opening 490 may result in a smaller central area 412.

[0072] A pixel layer 410 as described herein (which may refer to any pixel layer 410 of a pixel pattern deposited on the substrate 10) may have a pixel layer shape and a pixel layer orientation. The pixel layer shape of a pixel layer 410 may beunderstood as a shape of a perimeter of the pixel layer 410, e.g. a shape of a perimeter of the peripheral area 414 of the pixel layer 410. For example, the pixel layer shape may be a square shape or a hexagonal shape as illustrated in FIG. 4B, or a rectangular shape, or any other shape. The pixel layer orientation may be an angular orientation of the pixel layer 410 with respect to a central axis of the pixel layer 410. The central axis may be perpendicular to the substrate 10. In FIG. 4B, the central axis is perpendicular to the drawing page. For example, as shown in FIG.4B, a pixel layer 410 may have a square shape at a first pixel layer orientation (lefthand drawing in FIG. 4B), or a square shape at second pixel layer orientation (middle drawing in FIG. 4B, showing a square shape rotated at a 45 degrees angle with respect to the square on the left). It shall be understood that FIG. 4B only shows a few examples, and the pixel layers can be provided in a plurality of different shapes and orientations.

[0073] The pixel layer shape and / or the pixel layer orientation of a pixel layer 410 may depend on, or be determined by, a pixel opening shape and / or a pixel opening orientation of a pixel opening 490 facing the pixel layer 410.

[0074] A pixel opening 490 as described herein (which may refer to any pixel opening 490 of the mask structure 133) may have a pixel opening shape and a pixel opening orientation. The pixel opening shape of a pixel opening 490 may be understood as a shape of a perimeter of the pixel opening 490, e.g. a shape outlined by a peripheral edge 456 of the overhang 454 of the overhang structure corresponding to the pixel opening 490. The pixel opening shape may be a shape defined in a major plane of the mask structure 133. The major plane may be a plane parallel to the substrate 10. For example, a pixel opening shape may be a square shape, a hexagonal shape, a rectangular shape, or any other shape. The pixel opening orientation of a pixel opening 490 may be an angular orientation of the pixel opening 490 with respect to a central axis of the pixel opening 490. The central axis may be perpendicular to the major plane of the mask structure 133. In FIG. 4A, the central axis is perpendicular to the substrate 10. The pixel layer shape and / or the pixel layer orientation of a pixel layer 410 may correspond to the pixel opening shape and / or the pixel opening orientation of a pixel opening 490 facing the pixel layer 410.For example, a pixel opening 490 corresponding to the pixel layers 410 shown in FIG. 4B may have a square shape (for providing the pixel layer 410 in the left-hand drawing in FIG. 4B), a square shape at a 45 degrees angle (for providing the pixel layer 410 in the middle drawing in FIG. 4B), or a hexagonal shape (for providing the pixel layer 410 in the right-hand drawing in FIG. 4B).

[0075] FIGS. 5-8 show examples of a substrate 10 on which a pixel pattern, including a plurality of pixel layers 410 is deposited using the methods described herein, wherein the pixel layers 410 in question have different shapes and orientations. A pixel pattern may be a two-dimensional pattern extending in a first direction and a second direction. The first direction may be the transportation direction 102. The second direction may be the evaporation source direction 204. The pixel layers 410 of the pixel pattern may be separate areas of deposited source material that are spaced apart from each other. FIG. 5 shows pixel layers 410 having a rectangular shape. FIG. 6 shows pixel layers 410 having a square shape. FIG. 7 shows a pixel pattern including a combination of pixel layers 410 having a rectangular shape and pixel layers 410 having a square shape. FIG. 8 shows pixel layers 410 having a square shape rotated at 45 degrees angle (referred to herein as diamond pixel layers). Further examples, such as pixel layers having a hexagon shape, or another polygon shape, may be considered analogously.

[0076] FIGS. 9-12 show examples of mask structures 133 for providing the pixel patterns shown in FIGs. 5-8. The plurality of pixel openings 490 of a mask structure 133 may be arranged according to a pixel opening pattern. A pixel opening pattern may be a two-dimensional pattern extending in a first direction and a second direction. The first direction may be the transportation direction 102. The second direction may be the evaporation source direction 204. FIG. 9 shows pixel openings 490 having a rectangular shape, for providing the pixel layers 410 of FIG. 5. FIG. 10 shows pixel openings 490 having a square shape, for providing the pixel layers 410 of FIG. 6. FIG. 11 shows a pixel opening pattern including a combination of pixel openings 490 having a rectangular shape and pixel openings 490 having a square shape, for providing the pixel layers 410 of FIG. 7. FIG. 12 shows pixel openings 490 having a square shape rotated at 45 degrees angle (referred to herein asdiamond openings), for providing the pixel layers 410 of FIG. 8. Further examples, such as pixel openings having a hexagon shape, or another polygon shape, may be considered analogously.

[0077] According to embodiments described herein, the design of the shaping apertures 33, and in particular a shape and / or orientation of the shaping apertures, is adapted to the shape and / or orientation of pixel openings 490 of the mask structure 133 - and, accordingly, to the shape and / or orientation of the pixel layers 410 that are to be deposited on the substrate 10.

[0078] That the shape and / or orientation of the shaping apertures 33 is “adapted to” the shape and / or orientation of the pixel openings 490 can be understood in the sense that differently shaped / oriented shaping apertures 33 are used in conjunction with differently shaped / oriented pixel openings 490. Depending on the shape and / or orientation of the pixel openings 490, a suitable shape and / or orientation of the shaping apertures 33 may be selected. For example, for forming square pixel layers 410 (for which square pixel openings 490 are used), a shaping aperture 33 having a square or rectangular shape may be used. For forming diamond pixel layers 410 (for which diamond pixel openings 490 are used) a shaping aperture 33 having a diamond shape / orientation may be used.

[0079] The inventors have found that an adaptation of the shape / orientation of the shaping apertures 33 to the shape / orientation of the pixel openings 490 results in an improved material utilization. In conventional deposition processes, where the same design for the shaping apertures (e.g. circular apertures) is used irrespective of the design of the pixel layers to be deposited, a certain amount of evaporated source material is wasted due to the mismatch between the shape / orientation of the shaping apertures and the shape / orientation of the pixel openings. Conversely, such a waste can be avoided by adapting the shapes / orientations of the shaping apertures and the pixel openings to each other, as described herein. In particular, for a same initial amount of source material, deposition systems according to embodiments described herein are capable of forming thicker pixel layers as compared to a system that uses the same shaping apertures irrespective of the design of the pixel layers to be deposited.

[0080] FIGs. 13-16 show shaping apertures 33 having different shapes and orientations.

[0081] A shaping aperture 33 as described herein (which may refer to any shaping aperture 33 of the evaporation source 20) may have an aperture shape and an aperture orientation.

[0082] The aperture shape of a shaping aperture 33 may be a shape of a perimeter of the shaping aperture 33 in a sectional plane of the shaping aperture 33, such as a sectional plane 350 in FIG. 3. The sectional plane may be parallel to the substrate 10, or parallel to a major plane of the mask structure 133, or parallel to the evaporation source direction 204, or parallel to the transportation direction 102, or any combination thereof. The sectional plane may extend through the shaping aperture 33 at a distal end of the shaping aperture 33, e.g. an end closest to the substrate 10. The perimeter of the shaping aperture 33 may be defined by an inner perimeter of the peripheral sidewall 34. For example, the aperture shape of the shaping apertures 33 shown in FIGs. 13-16 may refer to the shape of the white area enclosed by the peripheral sidewall 34, e.g. a rectangular aperture shape (FIG. 13), a square aperture shape (FIGs. 14-15) or a hexagonal aperture shape (FIG. 16).

[0083] The aperture orientation of a shaping aperture 33 may be an angular orientation of the shaping aperture 33 with respect to a central axis of the shaping aperture 33. The central axis may extend through the shaping aperture 33 in a main emission direction of the shaping aperture. The main emission direction of the shaping aperture may be a main emission direction of the nozzle associated with the shaping aperture. The central axis of a shaping aperture 33 may be perpendicular to the substrate 10, or perpendicular to a major plane of the mask structure 133, or perpendicular to the evaporation source direction 204, or perpendicular to the transportation direction 102, or any combination thereof. The central axis may be perpendicular to the sectional plane 350 with respect to which the aperture shape of the shaping aperture 33 is defined. In FIGs. 13-16, the central axis of a shaping aperture may be perpendicular to the drawing plane. For example, the shaping apertures 33 in FIGs. 14 and 15 both have a same aperture shape (being a square shape), but have a different aperture orientation. The shapingaperture 33 in FIG. 15 is a square shape rotated at an angle of 45 degrees (“diamond aperture”) with respect to a central axis of the shaping aperture 33.

[0084] It shall be understood that FIGs. 13-16 only show a few possible examples of aperture shapes and aperture orientations, and that many other examples can be considered in a similar manner. For example, the aperture shape can be any polygonal shape, and said polygonal shape can have any angular orientation.

[0085] According to embodiments, at least one of the aperture shape and the aperture orientation of the plurality of shaping apertures 33 is adapted to at least one of the pixel opening shape and the pixel opening orientation of the plurality of pixel openings 490. The aperture shape may be adapted to the pixel opening shape and / or the aperture orientation may be adapted to the pixel opening orientation.

[0086] The property that at least one of the aperture shape and the aperture orientation of the shaping apertures 33 is “adapted to” at least one of the pixel opening shape and the pixel opening orientation of the pixel openings 490 may include several possible configurations of the shaping apertures 33 with respect to the pixel openings 490, as described in the following.

[0087] In one example, the aperture shape may correspond to the pixel opening shape and / or the aperture orientation may correspond to the pixel opening orientation. The aperture shape and the pixel opening shape may be the same shape and / or the aperture orientation and the pixel opening orientation may be the same orientation. For example, if the pixel openings 490 have a square shape at a 0 degrees orientation, as shown in FIG. 10 (for providing square pixel layers 410 as shown in FIG. 6), then shaping apertures 33 having a square shape at a 0 degrees orientation, as shown in FIG. 14, may be used. Likewise, if the pixel openings 490 have a square shape at a 45 degrees orientation (diamond openings), as shown in FIG. 12 (for providing diamond pixel layers 410 as shown in FIG. 8), then shaping apertures 33 having a square shape at a 45 degrees orientation, as shown in FIG.15, may be used. The same applies to, for example, shaping apertures having rectangular shapes (FIG. 13), hexagon shapes (FIG. 16), and other shapes and orientations.

[0088] Still, it is not necessary that the shaping apertures 33 and the pixel openings 490 have the same shape and / or the same orientation. The beneficial effects described herein, such as an improved material utilization, may also be achieved when certain portions of the shaping apertures 33 are aligned with corresponding portions of the pixel openings 490, without a need to provide the shaping apertures 33 with exactly the same shape and orientation as the pixel openings, as described in further detail in the following.

[0089] The property that at least one of the aperture shape and the aperture orientation of the shaping apertures 33 is adapted to at least one of the pixel opening shape and the pixel opening orientation of the pixel openings 490 may be understood in the sense that, at least, each pixel opening 490 has a first side extending in a first direction, and that each shaping aperture 33 has a cross-sectional area having a first side extending in the first direction. Accordingly, the first side of a pixel opening 490 may be aligned with the first side of a shaping aperture 33.

[0090] A side of a pixel opening 490, such as the first side presently considered, and likewise the second side and third side described below, may be understood as a portion of a contour of the pixel opening. The side may be a side of a polygon, if the pixel opening has a polygonal shape. A side of a pixel opening 490 may be at least a portion of a peripheral edge 456 of the pixel opening 490. For example, the pixel openings in FIGs. 9-12 have first sides 954, 1054, 1154 and 1254, respectively.

[0091] A side of a cross-sectional area of a shaping aperture 33, such as the first side presently considered, and likewise the second side and third side described below, may be understood as a portion of a contour of the cross-sectional area. The side may be a side of a polygon, if the cross-sectional area has a polygonal shape. The cross-sectional area can be taken in a sectional plane of the shaping aperture as defined above (e.g. sectional plane 350). A side of the cross-sectional area can be an inner side of the peripheral sidewall 34 defining the shaping aperture 33. For example, the shaping apertures in FIGs. 13-16 have first sides 1354, 1454, 1554 and 1654, respectively.

[0092] In an example, each pixel opening 490 in FIG. 9 has a first side 954 extending in the evaporation source direction 204. For improving the material utilization in the deposition process, a shaping aperture 33 having a first side in the same direction, such as the rectangular shaping aperture in FIG. 13 having a first side 1354 or the square shaping aperture in FIG. 14 having a first side 1454, may be used. Further, also differently shaped shaping apertures 33, i.e. different from the rectangular or square shaping apertures in FIGs. 13 and 14, may likewise provide an improved material utilization, if they have a first side extending in the evaporation source direction 204.

[0093] In a further example, each pixel opening 490 in FIG. 10 (square pixel openings) or FIG. 11 (combination of square and rectangular pixel openings) has a first side 1054 or 1154 extending in the evaporation source direction 204. For improving the material utilization in the deposition process, a shaping aperture 33 having a first side in the same direction may be used, including, but not limited to, the rectangular and square shaping apertures shown in FIGs. 13-14.

[0094] In a further example, each pixel opening 490 in FIG. 12 has a first side 1254 extending in a first direction, being a direction extending along a 45 degrees angle with respect to the evaporation source direction 204. For improving the material utilization in the deposition process, a shaping aperture 33 having a first side in the same direction may be used, including, but not limited to, diamond apertures shown in FIG. 15, having a first side 1554.

[0095] The property that at least one of the aperture shape and the aperture orientation of the shaping apertures 33 is adapted to at least one of the pixel opening shape and the pixel opening orientation of the pixel openings 490 may further include that each pixel opening 490 has a second side extending in a second direction different from the first direction, and that the cross-sectional area of each shaping aperture 33 has a second side extending in the second direction. Accordingly, the second side of a pixel opening 490 may be aligned with the second side of a shaping aperture 33.

[0096] The first side and the second side of each pixel opening 490 may be adjacent sides of the pixel opening 490. The first side and the second side of the cross-sectional area of each shaping aperture 33 may be adjacent sides of the cross-sectional area.

[0097] For example, the pixel openings in FIGs. 9-12 have first sides 954, 1054, 1154 and 1254, respectively, and second sides 952, 1052, 1152 and 1252, respectively. In each of the examples in question, the first side of a pixel opening is adjacent to the second side of the pixel opening. Further, the shaping apertures in FIGs. 13-16 have first sides 1354, 1454, 1554 and 1654, respectively, and second sides 1352, 1452, 1552 and 1652, respectively. In each of the examples in question, the first side of a shaping aperture is adjacent to the second side of the shaping aperture.

[0098] In an example, each pixel opening 490 in FIG. 9 has a second side 952 extending in the transportation direction 102. For further improving the material utilization in the deposition process, a shaping aperture 33 having a second side in the same direction, such as the rectangular shaping aperture in FIG. 13 having a second side 1352 or the square shaping aperture in FIG. 14 having a second side 1452, may be used. Further, also differently shaped shaping apertures 33 having a second side extending in the transportation direction 102 may likewise provide a further improved material utilization.

[0099] In a further example, each pixel opening 490 in FIG. 10 (square pixel openings) or FIG. 11 (combination of square and rectangular pixel openings) has a second side 1052 or 1152 extending in the transportation direction 102. For further improving the material utilization in the deposition process, a shaping aperture 33 having a second side in the same direction may be used, including, but not limited to, the rectangular and square shaping apertures shown in FIGs. 13-14.

[0100] In a further example, each pixel opening 490 in FIG. 12 has a second side 1252 extending in a second direction, being a direction extending along a -45 degrees angle with respect to the evaporation source direction 204. For further improving the material utilization in the deposition process, a shaping aperture 33having a second side in the same direction may be used, including, but not limited to, diamond apertures shown in FIG. 15, having a second side 1552.

[0101] The property that at least one of the aperture shape and the aperture orientation of the shaping apertures 33 is adapted to at least one of the pixel opening shape and the pixel opening orientation of the pixel openings 490 may further include that the cross-sectional area of each shaping aperture 33 has a third side extending in the first direction, particularly wherein the third side of the cross-sectional area is opposite to the first side of the cross-sectional area. Each pixel opening 490 may have a third side extending in the first direction, particularly wherein the third side of the pixel opening 490 is opposite to the first side of the pixel opening 490. Accordingly, the first side of a pixel opening and the third side of the pixel opening 490 may be aligned with the third side of a shaping aperture 33.

[0102] For example, the pixel openings in FIGs. 9-12 have first sides 954, 1054, 1154 and 1254, respectively, and third sides 956, 1056, 1156 and 1256, respectively. In each of the examples in question, the first side of a pixel opening is opposite to the third side of the pixel opening. Further, the shaping apertures in FIGs. 13-16 have first sides 1354, 1454, 1554 and 1654, respectively, and third sides 1356, 1456, 1556 and 1656, respectively. In each of the examples in question, the first side of a shaping aperture is opposite to the third side of the shaping aperture.

[0103] For example, each pixel opening 490 in FIG. 9 has a first side 954 and a third side 956 both extending in the evaporation source direction 204. For further improving the material utilization in the deposition process, a shaping aperture 33 having a first side and / or a third side in the same direction, such as the rectangular shaping aperture in FIG. 13 having a first side 1354 and a third side 1356, or the square shaping aperture in FIG. 14 having a first side 1454 and a third side 1456, may be used. Further, also differently shaped shaping apertures 33 having a first side and / or a third side extending in the evaporation source direction 204 may likewise provide a further improved material utilization.

[0104] Similar examples can be provided for the case of, e.g., square pixel openings (FIG. 10), combinations of square and rectangular pixel openings (FIG.11), diamond pixel openings (FIG. 12), hexagonal pixel openings, and the like, and the corresponding shaping apertures having first sides and / or third sides in alignment with the first sides and / or the third sides of the pixel openings in question.

[0105] The property that at least one of the aperture shape and the aperture orientation of the shaping apertures 33 is adapted to at least one of the pixel opening shape and the pixel opening orientation of the pixel openings 490 may further include that the aperture shape and the pixel opening shape are both N-sided polygon shapes for a same N. The number N may be greater than or equal to three, particularly greater than or equal to four. An N-sided polygon is a polygon having a total of N sides, i.e. N edges. For example, a rectangle and a square are both instances of four-sided polygons. A hexagon is a six-sided polygon.

[0106] According to embodiments, the pixel opening shape and the aperture shape may both be rectangular shapes. A rectangular shape includes square shapes and non-square rectangular shapes. For example, the pixel opening shapes and the aperture shapes in FIGs. 9 and 13 are non-square rectangular shapes, and the pixel opening shapes and the aperture shapes in FIGs. 10 and 14 are square rectangular shapes. The provision that the pixel opening shape and the aperture shape may both be rectangular shapes includes that the pixel opening shape and the aperture shape are both square shapes, that one of the pixel opening shape and the aperture shape is a square shape and the other one of the pixel opening shape and the aperture shape is a non-square rectangular shape, or that the pixel opening shape and the aperture shape are both non-square rectangular shapes.

[0107] According to embodiments, the pixel opening shape and the aperture shape may both be hexagon shapes.

[0108] The property that at least one of the aperture shape and the aperture orientation of the shaping apertures 33 is adapted to at least one of the pixel opening shape and the pixel opening orientation of the pixel openings 490 may further include that the plurality of shaping apertures has a first mean angular orientationdefined by a first angle with respect to a reference direction and the plurality of pixel openings has a second mean angular orientation defined by a second angle with respect to the reference direction, wherein the first angle is within 20 degrees of the second angle. Particularly, the first angle may be equal to the second angle. The first mean angular orientation may be a mean orientation obtained by taking a mean of the angular orientation over all shaping apertures of the plurality of shaping apertures. The second mean angular orientation may be a mean orientation obtained by taking a mean of the angular orientation over all pixel openings of the plurality of pixel openings. The reference direction may be a vertical direction. The reference direction may be the evaporation source direction 204.

[0109] The property that at least one of the aperture shape and the aperture orientation of the shaping apertures 33 is adapted to at least one of the pixel opening shape and the pixel opening orientation of the pixel openings 490 may further include that all shaping apertures of the plurality of shaping apertures have a substantially same angular orientation defined by a first angle (where “substantially” includes a possible deviation of 15 degrees) with respect to the reference direction and all pixel openings of the plurality of pixel openings have a substantially same angular orientation defined by a second angle (where “substantially” again includes a possible deviation of 15 degrees) with respect to the reference direction, wherein the first angle is within 20 degrees of the second angle. Particularly, the first angle may be equal to the second angle.

[0110] In other words, the angular orientations of the shaping apertures and of the pixel openings may be the same or at least similar to each other, deviating at most by 20 degrees. For example, the pixel openings of FIG. 9 have a rectangular shape at a 0 degrees angular orientation with respect to the evaporation source direction 204, being a same angular orientation as the rectangular shaping apertures of FIG. 13 or the square shaping apertures of FIG. 14.

[0111] The above-described property that the angular orientations of the shaping apertures and of the pixel openings may be the same or at least similar to each other may in particular apply to embodiments where the shaping apertures and thepixel openings have a same or at least similar shape, e.g. both shapes being rectangular, both shapes being hexagonal, and the like.

[0112] The effects of having shaping apertures having an aperture shape, and / or an aperture orientation that is adapted to the pixel opening shape, and / or the pixel opening orientation of the pixel openings are illustrated further with respect to FIGs.17-21.

[0113] FIG. 17 shows a portion of a deposition process as considered herein. The evaporation source 20, while moving in a transportation direction 102, emits a plume 318 of evaporated source material. A portion of the plume 318 passes through a pixel opening 490 of the mask structure 133 to deposit a pixel layer 410 on the substrate 10. For ease of presentation, only a single pixel opening 490 is shown. Yet it shall be understood that the discussion applies to all pixel openings of the mask structure. Further, it shall be understood that the dimensions in FIG. 17 (e.g. the dimensions of the pixel opening 490, of the shaping aperture 33 and of the plume 318) are not depicted true to scale.

[0114] FIG. 17 shows four positions (a), (b), (c) and (d) of the evaporation source 20 as the evaporation source moves from left to right over the substrate 10 in the transportation direction 102 during the deposition process. In position (a), the plume 318 has not reached the pixel opening 490, so that no source material is deposited through the pixel opening 490 on the substrate 10. Position (b) is the first position where a front portion 1702 of the plume 318 (i.e. a front surface of the emission cone) passes through the pixel opening 490 and reaches the substrate 10. Position (c) is the last position where the front portion 1702 of the plume 318 passes through the pixel opening 490 and reaches the substrate 10. As the evaporation source 20 continues to move towards the right, the front portion 1702 of the plume 318 no longer passes through the pixel opening 490. Further, in positions (a), (b) and (c) of FIG. 17, a rear portion 1704 (rear surface of the emission cone) of the plume 318 does not yet pass through the opening 490. Position (d) is the first position where the rear portion 1704 of the plume 318 passes through the pixel opening 490 and reaches the substrate 10.

[0115] In the present example it is assumed, for the sake of concreteness, but without implying any limitation, that the deposition process of FIG. 17 deposits a pixel pattern of rectangular-shaped pixel layers 410 on the substrate 10. Correspondingly, the pixel openings 490 of the mask structure 133 may also have a rectangular shape. Further, according to embodiments described herein, at least one of the aperture shape and the aperture orientation of the shaping apertures 33 is adapted to at least one of the pixel opening shape and the pixel opening orientation of the pixel openings 490. The adaptation in question may include that at least one of a first side, a second side and a third side of a cross-sectional area of the shaping apertures is aligned with (i.e. extends in the same direction as) at least one of a first side, a second side and a third side of the pixel openings. In the present example, but without implying any limitation, it is considered that the shaping apertures 33 have a square cross-sectional shape (at 0 degrees orientation), such as the shaping apertures shown in FIG. 14.

[0116] The aperture shape and / or the aperture orientation of a shaping aperture 33 may determine a shape and / or an orientation of the plume 318 emitted from the shaping aperture 33. The shape and / or the orientation of a cross-sectional area of the plume 318 (e.g. in a sectional plane of the plume 318 parallel to the substrate 10) may be the same as the aperture shape and / or the aperture orientation, respectively, of the shaping aperture 33. For instance, in the presently considered example of a square shaping aperture 33, the cross-sectional area of the plume 318 may be square as well, as illustrated in FIGs. 18-19.

[0117] FIG. 18 shows position (c) the plume 318 of FIG. 17 in a side view. Due to the fact that the aperture shape and the aperture orientation of the shaping aperture 33 are adapted to the pixel opening shape and the pixel opening orientation of the pixel opening 490, the front portion 1702 of the plume 318 aligns with the first side 954 of the pixel opening. The evaporated source material can be uniformly deposited along the length of the first side 954. No evaporated source material is wasted due to a mismatch between the front portion 1702 and the first side 954.

[0118] Similarly, FIG. 19 shows position (d) the plume 318 of FIG. 17 in a side view. Due to the fact that the aperture shape and the aperture orientation of theshaping aperture 33 are adapted to the pixel opening shape and the pixel opening orientation of the pixel opening 490, the rear portion 1704 of the plume 318 aligns with the third side 956 of the pixel opening 490. The evaporated source material can be uniformly deposited along the length of the third side 956. No evaporated source material is wasted due to a mismatch between the rear portion 1704 and the third side 956.

[0119] In contrast, different from embodiments described herein, FIG. 20 shows a circular plume 318 resulting from a circular shape of the shaping aperture 33. A circular shaping aperture 33 is not considered to be adapted to a rectangularly shaped pixel opening 490. As illustrated in FIG. 20, a mismatch exists between the first side 954 of the pixel opening 490 and the front portion 1702 of the plume 318. A portion of the evaporated source material is blocked by the circular shape of the shaping aperture 33, resulting in the mismatch between the first side 954 of the pixel opening 490 and the front portion 1702 of the plume 318. In other words, a circular shaping aperture 33 blocks more evaporated material than necessary for the purpose of depositing a rectangularly shaped pixel layer. In such a case, the material utilization is reduced.

[0120] In another example, FIG. 21 shows a plume 318 in a side view in the case of a diamond shaping aperture 33 being used for deposition of diamond pixel layers 410 (and, accordingly, using diamond pixel openings 490). In such a case, the cross-sectional area of the plume 318 will also have a diamond shape / orientation, as illustrated in FIG. 21. Due to the fact that the aperture shape and the aperture orientation of the shaping aperture 33 are adapted to the pixel opening shape and the pixel opening orientation of the pixel opening 490, the periphery of the plume 318 aligns with the sides 1252 and 1254 of the pixel opening 490. The evaporated source material can be uniformly deposited along the sides 1252 and 1254. No evaporated source material is wasted due to a mismatch between the plume 318 and the pixel opening 490.

[0121] According to a further embodiment, a method of manufacturing pixels on substrates is provided.

[0122] The method includes performing a first deposition process. The first deposition process includes guiding an evaporated source material through a first plurality of nozzles, each of the first plurality of nozzles generating a plume of evaporated source material propagating towards a first substrate. The first deposition process includes individually shaping the plumes of evaporated source material using a first plurality of shaping apertures, each of the shaping apertures of the first plurality of shaping apertures having a first aperture shape and a first aperture orientation. A portion of the plumes of evaporated source material passes through a first plurality of pixel openings of a first mask structure to deposit a first pixel pattern including a first plurality of pixel layers on the first substrate. Each pixel opening of the first plurality of pixel openings has a first pixel opening shape and a first pixel opening orientation.

[0123] The method includes performing a second deposition process. The second deposition process includes guiding an evaporated source material through a second plurality of nozzles, each of the second plurality of nozzles generating a plume of evaporated source material propagating towards a second substrate. The second plurality of nozzles is equal to, or different from, the first plurality of nozzles. The second substrate is equal to, or different from, the first substrate. The second deposition process includes individually shaping the plumes of evaporated source material using a second plurality of shaping apertures, each of the shaping apertures of the second plurality of shaping apertures having a second aperture shape and a second aperture orientation. The second aperture shape is different from the first aperture shape and / or the second aperture orientation is different from the first aperture orientation. A portion of the plumes of evaporated source material passes through a second plurality of pixel openings of a second mask structure to deposit a second pixel pattern including a second plurality of pixel layers on the second substrate, each pixel opening of the second plurality of pixel openings having a second pixel opening shape and a second pixel opening orientation. The second pixel opening shape is different from the first pixel opening shape, and / or the second pixel opening orientation is different from the first pixel opening orientation.

[0124] For the sake of illustration, but without implying a limitation, the first deposition process may e.g. involve the usage of square shaping apertures (FIG.14) for depositing square pixel layers (FIG. 6), and the second deposition process may e.g. involve the usage of diamond shaping apertures (FIG. 15) for depositing diamond pixel layers (FIG. 8).

[0125] The first / second plurality of nozzles, the first / second substrate, the first / second plurality of shaping apertures, the first / second mask structure and the first / second plurality of pixel layers may have any properties, or combination of properties, of a plurality of nozzles 22, a substrate 10, a plurality of shaping apertures 33, a mask structure 133 and a plurality of pixel layers 410 as described herein.

[0126] The first aperture shape may be an N-sided polygon shape and the second aperture shape may be an M-sided polygon shape, where N is different from M. Additionally, or alternatively, the first pixel opening shape may be a K-sided polygon shape and the second pixel opening shape may be an L-sided polygon shape, where K is different from L. In some cases, N = K and M = L.

[0127] The first aperture shape and the second aperture shape may be a same shape, wherein the second aperture orientation may be different from the first aperture orientation. The second aperture orientation may be rotated with respect to the first aperture orientation. Additionally, or alternatively, the first pixel opening shape and the second pixel opening shape may be a same shape, wherein the second pixel opening orientation may be different from the first pixel opening orientation. The second pixel opening orientation may be rotated with respect to the first pixel opening orientation.

[0128] According to a further embodiment, an apparatus for manufacturing pixels on a substrate 10 is provided. The apparatus includes a substrate support. The apparatus includes an evaporation source 20 for guiding an evaporated source material through a plurality of nozzles 22 of the evaporation source 20, each of the plurality of nozzles 22 configured to generate a plume 318 of evaporated source material propagating towards the substrate 10 supported by the substrate support.The evaporation source 20 includes a plurality of shaping apertures 33 to individually shape the plumes 318 of evaporated source material, each shaping aperture 33 of the plurality of shaping apertures having an aperture shape and an aperture orientation. The apparatus is configured such that a portion of the plumes 318 of evaporated source material passes through a plurality of pixel openings 490 of a mask structure 133 to deposit a pixel pattern including a plurality of pixel layers 410 on the substrate 10, each pixel opening 490 of the plurality of pixel openings having a pixel opening shape and a pixel opening orientation. At least one of the aperture shape and the aperture orientation of the plurality of shaping apertures 33 is adapted to at least one of the pixel opening shape and the pixel opening orientation of the plurality of pixel openings 490. The apparatus may be configured, e.g. under the control of a controller that is part of the apparatus, to perform any operation or combination of operations included in the method described herein.

[0129] The 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 they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.

Claims

WHAT IS CLAIMED IS:

1. A method of manufacturing pixels on a substrate (10), comprising:guiding an evaporated source material through a plurality of nozzles (22) of an evaporation source (20), each of the plurality of nozzles generating a plume (318) of evaporated source material propagating towards the substrate; and individually shaping the plumes of evaporated source material using a plurality of shaping apertures (33), each shaping aperture of the plurality of shaping apertures having an aperture shape and an aperture orientation,wherein a portion of the plumes of evaporated source material passes through a plurality of pixel openings (490) of a mask structure to deposit a pixel pattern including a plurality of pixel layers (410) on the substrate, each pixel opening (490) of the plurality of pixel openings having a pixel opening shape and a pixel opening orientation,wherein at least one of the aperture shape and the aperture orientation of the plurality of shaping apertures is adapted to at least one of the pixel opening shape and the pixel opening orientation of the plurality of pixel openings.

2. The method of claim 1, wherein the aperture shape of a shaping aperture (33) is a shape of a perimeter of the shaping aperture in a sectional plane parallel to the substrate and / or wherein the aperture orientation of a shaping aperture is an angular orientation of the shaping aperture with respect to a central axis of the shaping aperture.

3. The method of claim 1 or 2, wherein the pixel opening shape of a pixel opening (490) is a shape of a perimeter of the pixel opening and / or the pixel opening orientation of a pixel opening is an angular orientation of the pixel opening with respect to a central axis of the pixel opening.

4. The method of any of the preceding claims, wherein each pixel opening (490) of the plurality of pixel openings has a first side (954, 1054, 1154, 1254) extending in a first direction, wherein each shaping aperture (33) of the plurality of shapingapertures has a cross-sectional area having a first side (1354, 1454, 1554, 1654) extending in the first direction.

5. The method of claim 4, wherein each pixel opening (490) of the plurality of pixel openings has a second side (952, 1052, 1152, 1252) extending in a second direction different from the first direction, wherein the cross-sectional area of each shaping aperture (33) of the plurality of shaping apertures has a second side (1352, 1452, 1552, 1652) extending in the second direction,particularly wherein the first side and the second side of each pixel opening are adjacent sides of the pixel opening and wherein the first side and the second side of the cross-sectional area of each shaping aperture are adjacent sides of the cross-sectional area.

6. The method of claim 4 or 5, wherein the cross-sectional area of each shaping aperture (33) of the plurality of shaping apertures has a third side (1356, 1456, 1556, 1656) extending in the first direction, particularly wherein the third side is opposite to the first side of the cross-sectional area.

7. The method of any of the preceding claims, wherein the aperture shape and the pixel opening shape are both N-sided polygon shapes for a same N.

8. The method of any of the preceding claims, wherein the pixel opening shape and the aperture shape are both rectangular shapes.

9. The method of claim 7 or 8, wherein the plurality of shaping apertures has a first mean angular orientation defined by a first angle with respect to a reference direction and the plurality of pixel openings has a second mean angular orientation defined by a second angle with respect to the reference direction, wherein the first angle is within 20 degrees of the second angle.

10. The method of any of the preceding claims, wherein the mask structure is permanently formed on the substrate, the mask structure including a plurality ofoverhang structures, each overhang structure having a body portion (452) and an overhang (454) protruding from the body portion at a height above the substrate, the overhang defining a pixel opening (490) of the plurality of pixel openings of the mask structure.

11. The method of any of the preceding claims, wherein each shaping aperture (33) of the plurality of shaping apertures is arranged at a nozzle (22) of the plurality of nozzles without contacting the nozzle.

12. The method of any of the preceding claims, wherein each shaping aperture (33) of the plurality of shaping apertures is defined by a peripheral sidewall (34) providing a passage (43) fora plume (318) of evaporated source material generated by a nozzle (22) of the plurality of nozzles, wherein the peripheral sidewall blocks evaporated source material having an emission angle greater than a maximum emission angle.

13. The method of any of the preceding claims, wherein the evaporated source material is an organic material, particularly an OLED material.

14. A method of manufacturing pixels on substrates, comprising:performing a first deposition process, comprising:guiding an evaporated source material through a first plurality of nozzles, each of the first plurality of nozzles generating a plume of evaporated source material propagating towards a first substrate; and individually shaping the plumes of evaporated source material using a first plurality of shaping apertures, each of the shaping apertures of the first plurality of shaping apertures having a first aperture shape and a first aperture orientation,wherein a portion of the plumes of evaporated source material passes through a first plurality of pixel openings of a first mask structure to deposit a first pixel pattern including a first plurality of pixel layers on the first substrate,each pixel opening of the first plurality of pixel openings having a first pixel opening shape and a first pixel opening orientation; andperforming a second deposition process, comprising:guiding an evaporated source material through a second plurality of nozzles, each of the second plurality of nozzles generating a plume of evaporated source material propagating towards a second substrate, the second plurality of nozzles being equal to or different from the first plurality of nozzles, the second substrate being equal to or different from the first substrate; andindividually shaping the plumes of evaporated source material using a second plurality of shaping apertures, each of the shaping apertures of the second plurality of shaping apertures having a second aperture shape and a second aperture orientation, wherein the second aperture shape is different from the first aperture shape and / or the second aperture orientation is different from the first aperture orientation,wherein a portion of the plumes of evaporated source material passes through a second plurality of pixel openings of a second mask structure to deposit a second pixel pattern including a second plurality of pixel layers on the second substrate, each pixel opening of the second plurality of pixel openings having a second pixel opening shape and a second pixel opening orientation, wherein the second pixel opening shape is different from the first pixel opening shape and / or the second pixel opening orientation is different from the first pixel opening orientation.

15. An apparatus for manufacturing pixels on a substrate (10), comprising:a substrate support; andan evaporation source (20) for guiding an evaporated source material through a plurality of nozzles (22) of the evaporation source, each of the plurality of nozzles configured to generate a plume (318) of evaporated source material propagating towards the substrate supported by the substrate support,the evaporation source comprising a plurality of shaping apertures (33) to individually shape the plumes of evaporated source material, each shaping apertureof the plurality of shaping apertures having an aperture shape and an aperture orientation,the apparatus being configured such that a portion of the plumes of evaporated source material passes through a plurality of pixel openings (490) of a mask structure to deposit a pixel pattern including a plurality of pixel layers (410) on the substrate, each pixel opening (490) of the plurality of pixel openings having a pixel opening shape and a pixel opening orientation,wherein at least one of the aperture shape and the aperture orientation of the plurality of shaping apertures is adapted to at least one of the pixel opening shape and the pixel opening orientation of the plurality of pixel openings.

Images