Linear evaporation source and co-evaporation evaporation source

Abstract

The application discloses a linear evaporation source and a co-evaporation evaporation source, and belongs to the technical field of vacuum coating equipment, and aims to solve the problems of uneven heating, serious heat radiation overflow, easy condensation of nozzles and inconvenient maintenance in the prior art. The linear evaporation source comprises a body provided with a chamber and a nozzle, and the key lies in that a slit not penetrating to the chamber is formed in the body, a heating source is arranged in the slit, and the heating source heats the body wall where the chamber is located. The design realizes efficient and uniform direct heating, heat conduction through the body wall can effectively heat the nozzle to prevent condensation, and the modular structure is convenient for maintenance. The slit is arranged on the bottom and the top or the two side walls to optimize the heat field and inhibit heat radiation. In addition, a main stem-branch stem type heating network, an in-chamber rectifying plate or a plurality of units integrated to form a co-evaporation source can be further arranged. The application is particularly suitable for evaporation of high-melting-point materials such as metals, and has the advantages of high heating efficiency, precise temperature control, good film thickness uniformity and convenient maintenance.

Description

Technical Field

[0001] This invention relates to the field of vacuum coating equipment technology, and in particular to a linear evaporation source and a co-evaporation evaporation source. Background Technology

[0002] Vacuum evaporation is a key process for preparing various functional thin films. In the field of OLED displays, organic light-emitting layers are typically deposited using linear evaporation sources, while electrode layers (such as metal cathodes) are mostly deposited using point sources. As display panels evolve towards higher generations, point sources, due to their small deposition area, slow speed, and poor film thickness uniformity, can no longer meet the demands of large-size, high-efficiency production. Therefore, developing linear evaporation sources suitable for high-melting-point materials such as metals has become an urgent need.

[0003] Existing linear evaporation sources are primarily designed for organic materials. A typical structure is exemplified by an OLED linear evaporation source device disclosed in patent publication number CN212669786U, where heating components (such as heating wires) are wound around the outside of the evaporation chamber. This external heating method has significant drawbacks: First, it suffers from low heat transfer and utilization efficiency, and for evaporation materials with low thermal conductivity, such as powdered or blocky materials, it easily leads to uneven heating. Second, when used for materials requiring high temperatures (typically greater than 500°C or even exceeding 1000°C), such as metals, higher heating power is needed to achieve a sufficient evaporation rate. This causes a rapid increase in temperature of the evaporation source body and surrounding components, resulting in intense thermal radiation. Excessive thermal radiation can raise the temperature of the substrate above, leading to the degradation of the organic functional layer already deposited on the substrate, and also affecting the performance and lifespan of other precision components within the vacuum chamber.

[0004] For example, patent publication number CN117535630A discloses a linear metal evaporator source with a graphite inner liner that maintains the saturated vapor pressure of the steam through zoned temperature control. Although this solution can achieve high-temperature heating, it has a complex structure, high processing, maintenance and replacement costs for the graphite self-heating inner liner, and the independent control of multiple temperature zones increases the system complexity.

[0005] In addition, another challenge faced by the above-mentioned solutions is nozzle temperature control. If the nozzle temperature is too low, the evaporated material vapor is prone to condensation and adhesion on the inner wall of the nozzle, which can clog the nozzle in severe cases, affecting the uniformity and stability of the vapor deposition. If a separate heating source is set for the nozzle, the heat utilization efficiency is low, increasing the complexity of the structure and the difficulty of control.

[0006] Therefore, there is an urgent need for a new type of linear evaporation source that can achieve efficient and uniform high-temperature heating, effectively suppress heat radiation overflow, precisely control nozzle temperature, and facilitate maintenance and material filling. Summary of the Invention

[0007] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a linear evaporation source and a co-evaporation evaporation source to solve the problems of low heating efficiency, poor thermal uniformity, serious heat radiation overflow, easy condensation of nozzles, and inconvenient maintenance in the prior art.

[0008] A linear evaporation source includes a body and a nozzle disposed on the top of the body. The body has a chamber for containing evaporation material, and the nozzle communicates with the chamber.

[0009] The top of the body is provided with at least one non-connecting slit that protrudes into the interior of the cavity;

[0010] It also includes a heating source installed within the slit;

[0011] The heating source heats the evaporation material in the chamber, the nozzle, and the inner wall of the body.

[0012] In this invention, the bottom of the main body is also provided with at least one non-connected slit that protrudes into the interior of the cavity, and a heating source is provided in the slit at the bottom.

[0013] Furthermore, the slit and heating source at the top of the body are located beside the nozzle; and / or, the slit at the bottom of the body avoids the orthographic projection area of ​​the nozzle; the extending direction of the slit and heating source is parallel or perpendicular to the extending direction of the nozzle.

[0014] In this invention, the heating source within the slit is fixed by a support or a base.

[0015] In this invention, the at least one slit includes a main slit extending along the length direction of at least one body in a straight line, a broken line, or a curve, and multiple bodies can be spliced ​​together sequentially.

[0016] Furthermore, when the slit is a straight main slit, multiple branch slits extending along the width direction of the body are provided on both sides of the main slit.

[0017] In this invention, the heating source is a plate heater.

[0018] In this invention, the chamber is provided with a crucible whose shape is adapted to the interior of the chamber; and / or, the chamber is provided with at least one rectifier plate with through holes or recesses located below the nozzle.

[0019] In this invention, the main body is fitted with an outer shell and an openable upper cover. Both the upper cover and the outer shell include a heat-reflective layer and a cooling layer. Gaps are provided between the heat-reflective layer and the outer wall of the main body, and between the heat-reflective layer and the cooling layer.

[0020] An auxiliary heating layer is also provided between the heat reflective layer and the outer wall of the main body.

[0021] The present invention also provides a co-evaporation source, comprising at least two linear evaporation sources as described in any one of the above, wherein the at least two linear evaporation sources are arranged side by side and their nozzles are arranged in the same straight line direction; and / or, the at least two linear evaporation sources share a common outer shell and top cover; the jet flow directions of the nozzle arrays of the parallel linear evaporation sources converge at the substrate.

[0022] The beneficial effects of this invention are:

[0023] The linear evaporation source provided by this invention achieves efficient, uniform, and direct high-temperature heating of the evaporation material by embedding and suspending an electric heater in a slit within the main body wall. This results in high thermal efficiency and avoids contamination of the chamber by the electric heater. This structure allows heat to be efficiently conducted to the nozzle through the main body wall, effectively preventing vapor condensation and blockage. The entire component can be modularly disassembled for easy maintenance and material filling. At the same time, the arrangement of the slits (such as avoiding the nozzle's direct projection area) effectively suppresses the direct dissipation of high-temperature heat radiation to the substrate, protecting the deposited organic functional layer and surrounding precision components. Furthermore, by setting a main-branch heating network, rectifier plate, or co-evaporation integrated structure, the heating uniformity, vapor homogenization effect, and multifunctional applicability are further improved, making it particularly suitable for evaporating high-melting-point materials such as metals. Attached Figure Description

[0024] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0025] Figure 1 This is a schematic diagram of the longitudinal cross-section of the evaporation source with the slit located at the bottom of the main body in Example 1;

[0026] Figure 2 This is a schematic diagram of the longitudinal cross-section of the evaporation source with the slit located at the top of the main body in Example 1;

[0027] Figure 3 This is a schematic diagram of the longitudinal cross-section of the evaporation source in Example 1, where the slits are simultaneously located at the top and bottom of the main body;

[0028] Figure 4 This is a schematic longitudinal cross-sectional view of the evaporation source in Example 2;

[0029] Figure 5 This is a schematic diagram of how the bottom slit avoids the direct spray area of ​​the nozzle in Example 3;

[0030] Figure 6 This is a schematic diagram of the slit being laterally arranged on the side wall of the body in Embodiment 4;

[0031] Figure 7This is a schematic diagram of the electric heater inside the slit being fixed by a support in Example 4;

[0032] Figure 8 This is a schematic diagram of the slit and electric heater being laterally embedded in the top wall of the main body in Example 5;

[0033] Figure 9 This is a schematic diagram of multiple slits provided along the width direction on the main body in Example 6;

[0034] Figure 10 This is a schematic diagram of various thermal field distribution structures in Example 7;

[0035] Figure 11 This is a schematic diagram of the evaporation source chamber with a rectifier plate in Example 8;

[0036] Figure 12 This is a schematic diagram of the structure of the co-evaporization evaporation source in Example 9;

[0037] Figure 13 This is a schematic diagram of the jet direction of the nozzle array between two adjacent linear evaporation source units in Example 9;

[0038] The attached figures are labeled as follows: 1-body, 2-nozzle, 3-electric heater, 4-base, 5-evaporation material, 6-crucible, 7-rectifier plate, 8-heat reflective layer, 9-cooling layer, 10-auxiliary heating layer, 11-chamber, 12-slit, 13-support, 14-outer shell, 15-top cover, 100-linear evaporation source unit, 12a-main slit, 12b-branch slit, 3a-main electric heater, 3b-branch electric heater, 200-guide nozzle. Detailed Implementation

[0039] This invention provides a linear evaporation source and a co-evaporation evaporation source. To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention.

[0040] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0041] Example 1:

[0042] like Figures 1 to 3As shown, this embodiment provides a linear evaporation source, specifically including a body 1 and nozzles 2. The body 1 is elongated and has an elongated chamber 11 inside for accommodating evaporation material 5. The nozzles 2 are located at the top center of the body 1 and are arranged in multiple ways along the length of the body 1. The bottom of the nozzles 2 communicates with the chamber 11.

[0043] At least one slit 12 extending along the length of the body 1 is provided on both sides of the bottom and / or top nozzle 2 of the body 1. Among the above-mentioned solutions, the preferred solution of this embodiment is that slits 12 are provided on both sides of the bottom and top nozzle 2 of the body 1 to achieve the best heating effect.

[0044] The slit 12 extends inward from the outer wall of the main body 1 but terminates within the main body wall and does not penetrate into the cavity 11, thus maintaining the airtightness of the cavity 11. It also includes a heating source disposed within the slit 12 to heat the evaporation material 5 within the cavity 11 or the inner wall of the main body 1. The heating source can be an electric heater 3, an open flame electric heater, or a medium heater (such as a water bath, oil bath, sand bath, or steam bath). In this embodiment, the heating source is preferably a long, thin, strip-shaped electric heater 3. The electric heaters 3 in the top and bottom slits 12 are supported and fixed by the base 4. After the electric heaters 3 are fixed, their two wide surfaces (i.e., heating surfaces) face the left and right sides of the main body wall, respectively, thereby efficiently heating the evaporation material 5 and the nozzle 2 within the cavity 11 simultaneously through heat radiation and heat conduction. Since the electric heater 3 is embedded, heat is concentrated and transferred inward, reducing heat loss.

[0045] In addition, the main body 1 is provided with an outer shell 14 and an openable upper cover 15. Both the outer shell 14 and the upper cover 15 include an inner heat-reflective layer 8 and an outer cooling layer 9. When it is necessary to add evaporation material 5 or clean the chamber 11, simply open the upper cover 15 and lift the main body 1 vertically upward to separate the main body 1 from the outer shell 14. The operation is extremely simple.

[0046] Example 2:

[0047] like Figure 4As shown, this embodiment is an improvement on the preferred embodiment of Embodiment 1. Its structure is similar to the preferred embodiment of Embodiment 1, but the difference lies in that: the base 4 is removed in this embodiment, and a support member 13 is provided inside the slit 12 to fix the electric heater 3. The support member 13 can be an insulating ceramic sheet, strip, boss, or locking block structure disposed on the inner walls of both sides of the slit 12 or on the electric heater 3. It engages with the edge or surface of the electric heater 3 to suspend it or fix it at a predetermined position within the slit 12 at a specific distance. The core function of the support member 13 is to achieve precise and stable positioning and mechanical fixation of the electric heater 3 inside the slit 12, preventing it from shifting or deforming during operation.

[0048] Furthermore, an auxiliary heating layer 10 may be provided between the exterior of the main body 1 and the outer shell 14 to supplement the heat lost from the side.

[0049] Furthermore, a crucible 6 with a shape adapted to the interior of the chamber 11 can be provided inside the chamber 11 to provide a pure, controllable, and efficient heating platform for the evaporation material, thereby ensuring the stability of the evaporation process.

[0050] Example 3:

[0051] like Figure 5 As shown, this embodiment is a further improvement on embodiment 2. Its structure is similar to embodiment 2, but the difference lies in the arrangement of the slit 12 located at the bottom of the body 1 and the electric heater 3 fixed therein. These elements completely avoid the vertical projection area of ​​the nozzle 2, instead concentrating on the sides of the body. This arrangement ensures sufficient heating of the material and effective heating of the nozzle 2 through the sidewalls and top of the body, while further reducing the risk of heat radiation from the highest temperature zone of the electric heater 3 directly irradiating the substrate above through the nozzle channel, making it more suitable for heat-sensitive substrates.

[0052] Example 4:

[0053] like Figure 6 As shown, the only difference between this embodiment and Embodiment 1 is the location of the slits 12. Specifically, multiple slits 12 are formed laterally on the side wall of the body 1, that is, perpendicular to the length of the nozzle. The electric heater 3 is inserted laterally into the slits 12 and fixed by the base. The heating surfaces on both sides of the electric heater 3 face the inside and outside of the body 1, respectively. This arrangement naturally creates a steam homogenization space between the electric heater 3 and the top of the body 1, while also effectively heating the nozzle area.

[0054] Furthermore, such as Figure 7 As shown, the electric heater 3, which is inserted laterally into the slit 12, can also be fixed by the support member 13.

[0055] Example 5:

[0056] like Figure 8 As shown, the difference between this embodiment and embodiment 3 lies in the arrangement of the slit 12 at the top of the body 1. Specifically, the slits 12 and the electric heater 3, which are vertically arranged on both sides of the nozzle 2 at the top of the body 1, are horizontally embedded in the top position of the body 1. Specifically, slits 12 are horizontally formed on the top wall of the body 1 on both sides of the nozzle 2, and the electric heater 3 is embedded therein. The electric heater 3 within the slit 12 is fixed by a support member 13. This arrangement directly and efficiently utilizes heat conduction to heat the root of the nozzle 2, thereby preventing nozzle condensation; simultaneously, the lower heating surface of the electric heater 3 can also provide auxiliary heating to the evaporation material 5 below.

[0057] Example 6:

[0058] like Figure 9 As shown, this embodiment provides another arrangement of the slits 12, such as providing multiple parallel slits 12 in the width direction of the body 1. Each of these slits 12 is equipped with an electric heater 3. These electric heaters 3 divide the chamber 11 into multiple sub-chambers in the width direction. These sub-chambers are interconnected at the top, forming a common evaporation space and communicating with the nozzle 2. This structure increases the heating area, improves heating density and uniformity, and is more suitable for materials requiring higher evaporation temperatures. In this embodiment, the electric heaters 3 in the slits 12 can be fixed by the base 4 or by the support member 13. Preferably, the electric heaters 3 in the bottom slits 12 are fixed by the base, and the electric heaters 3 in the top slits 12 are fixed by the support member 13.

[0059] Example 7:

[0060] This embodiment mainly provides various linear evaporation sources with optimized thermal field distribution. For example... Figure 10 As shown in Figure a, a main slit 12a is provided in the central region along the length direction of the bottom of the main body 1. On both sides of the main slit 12a, a number of parallel branch slits 12b are provided, extending outward along the width direction of the main body. The main slit 12a and each branch slit 12b are opened from the outer wall of the main body inward, but none of them penetrate into the interior of the chamber 11.

[0061] Furthermore, each of the main slits 12a and branch slits 12b is equipped with an electric heater 3 and fixed by a support member 13 (not shown in the figure). It should be noted that the electric heater 3 includes a main electric heater 3a located in the main slit 12a and branch electric heaters 3b located in each branch slit 12b. This "main-branch" slit and electric heater 3 layout constitutes a highly efficient distributed heating network, and this design provides extremely high heating power density, making it ideal for evaporating metals with extremely high melting points. Simultaneously, the interior is divided into smaller sub-chambers, which effectively suppresses the sloshing of liquid material during the vapor deposition scanning process when the evaporating material is in a molten state, thereby stabilizing the vapor source and improving film thickness uniformity.

[0062] Not limited to the above-described embodiments, such as Figure 10 As shown in Figure b, to reduce the number of electric heaters used, the electric heater 3 can be configured as a wavy structure that bends back and forth, or as shown in Figure b. Figure 10 As shown in Figure c, the back-and-forth zigzag structure of the above two single-group electric heater 3 structures not only increases resistance but also facilitates control. Correspondingly, a slit 12 adapted to the wavy or zigzag structure is provided on the body 1. The electric heater 3 is installed in the slit 12. The shape of the slit 12 and the electric heater 3 increases the damping of the oscillation of the liquid material inside the body 1, which can suppress the sloshing of the liquid material.

[0063] It should also be noted that the implementation structure in this embodiment is not limited to being set on a single body 1, but multiple bodies 1 can also be spliced ​​together in sequence to form a linear evaporation source group of the required length.

[0064] Example 8:

[0065] like Figure 11 As shown, this embodiment adds a rectification structure based on any of the above embodiments. One or more rectification plates 7 are disposed inside the chamber 11, below the nozzle 2. Multiple through holes are formed on the rectification plates 7. When the vapor generated by the evaporation material moves upward through the through holes, its flow path is obstructed and mixed, thereby achieving sufficient homogenization along the length of the evaporation source. This ultimately makes the vapor ejected from the nozzle 2 more uniform, resulting in a coating with better film thickness uniformity. The rectification plates 7 can contact or be fixedly connected to the inner wall of the body 1.

[0066] Example 9:

[0067] like Figure 12As shown, this embodiment provides a co-evaporation source. It includes two parallel linear evaporation source units 100, as described in any of Embodiments 1-8. Each linear evaporation source unit 100 has an independent body 1, nozzle 2, and heating system. The nozzles 2 of the two linear evaporation source units 100 are arranged in the same straight line direction, allowing for the deposition of different materials. The two linear evaporation source units 100 are integrated into a common housing 14, achieving shared heat insulation and cooling systems and simplifying the overall structure.

[0068] In addition, such as Figure 13 As shown, the jetting direction of the nozzles 2 rows of two adjacent linear evaporation source units 100 points to the same position on the substrate A. Specifically, the angle can be adjusted according to the relative distance between the nozzle 2 and the substrate A (the adjustment method can be to replace the guide nozzle 200 with a different angle) to optimize the mixing state of the vapor flow of the two materials and obtain the ideal co-evaporation coating layer composition.

[0069] Supplementary Explanation

[0070] In all the above embodiments, the material of the body 1 can be stainless steel, titanium, tantalum, molybdenum, tungsten, niobium, rhenium, osmium, graphite, ceramics, or composite materials thereof to adapt to different temperature and chemical environments. The material of the electric heater 3 can be tantalum, molybdenum, tungsten, graphite, nickel-chromium alloys, etc. When both the body 1 and the electric heater 3 are conductive materials (such as stainless steel, molybdenum, tungsten, tantalum, graphite, etc.), the support member 13 must be made of insulating and high-temperature resistant materials such as alumina, boron nitride, ceramic fiber, etc. The heat reflective layer 8 can be made of polished metal plate (such as stainless steel, aluminum). The cooling layer 9 can be provided with circulating coolant channels. The auxiliary heating layer 10 can be used to compensate for edge heat loss.

[0071] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the embodiments described. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of the present invention.

Claims

1. A linear evaporation source, comprising a body and a nozzle disposed on the top of the body, wherein the body has a chamber for containing evaporation material, and the nozzle communicates with the chamber, characterized in that: The top of the body has at least one slit that opens inward from the outer wall of the body but terminates inside the body wall and does not extend into the interior of the cavity. It also includes a heating source that can be detachably mounted in the slit via a support or base; The heating source is a plate heater. The two wide surfaces of the plate heater are arranged opposite to the two inner sidewalls of the slit. The heat generated by the heating source is directly introduced into the main body wall through the inner sidewall of the slit, and then evenly conducted to the inner wall of the cavity, the evaporation material and the nozzle through the main body wall. The heating source heats the evaporation material in the chamber, the nozzle, and the inner wall of the body.

2. The linear evaporation source according to claim 1, characterized in that: The bottom of the body is also provided with at least one non-connected slit that protrudes into the interior of the cavity, and a heating source is provided in the slit at the bottom.

3. The linear evaporation source according to claim 2, characterized in that: The slit and heating source at the top of the body are located beside the nozzle; and / or, the slit at the bottom of the body avoids the orthographic projection area of ​​the nozzle; the extension direction of the slit and heating source is parallel or perpendicular to the extension direction of the nozzle.

4. The linear evaporation source according to claim 1 or 2, characterized in that: The at least one slit includes a main slit extending along the length of at least one body in a straight line, a broken line, or a curve, and multiple bodies can be spliced ​​together sequentially.

5. The linear evaporation source according to claim 4, characterized in that: When the slit is a straight main slit, multiple branch slits extending along the width of the body are also provided on both sides of the main slit.

6. The linear evaporation source according to claim 1 or 2, characterized in that: The chamber is provided with a crucible whose shape is adapted to the interior of the chamber; and / or, the chamber is provided with at least one rectifier plate with through holes or notches located below the nozzle.

7. The linear evaporation source according to claim 1 or 2, characterized in that: The main body is fitted with an outer shell and an openable upper cover. Both the upper cover and the outer shell include a heat-reflective layer and a cooling layer. There are gaps between the heat-reflective layer and the outer wall of the main body, and between the heat-reflective layer and the cooling layer. An auxiliary heating layer is also provided between the heat reflective layer and the outer wall of the main body.

8. A co-evaporation deposition evaporation source, characterized in that: It includes at least two linear evaporation sources as described in any one of claims 1 to 7, wherein the at least two linear evaporation sources are arranged side by side and their nozzles are arranged in the same straight direction; and / or, the at least two linear evaporation sources share a common outer shell and top cover; the jet flow directions of the nozzle arrays of the parallel linear evaporation sources converge at the substrate.

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