Crucible for evaporation
By setting a barrier member and arcuate side wall in the evaporation crucible, the thermal expansion stress problem during secondary heating of the metal evaporation residue is solved, the strength and stability of the crucible is improved, and the risk of thermal expansion and extrusion failure is reduced.
Patent Information
- Application Number
- CN202321671614.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-06-28
- Publication Date
- 2025-08-08
- Estimated Expiration
- 2033-06-28
AI Technical Summary
During the evaporation process, the thermal expansion stress generated by the secondary heating of the metal vapor deposition material will squeeze the crucible, causing the crucible edge to break.
A crucible for evaporation is designed, including the crucible side wall, the crucible bottom plate and the barrier member. The barrier member is fixed parallel to the bottom plate, adopting a semicircular or baffle structure to separate the space inside the crucible, combining the arcuate side wall and a double-layer structure to reduce the effect of thermal expansion stress on the side wall.
Effectively reduce the force of thermal expansion of metal vapor deposition materials on the side walls of crucibles, reduce the risk of damage, improve the strength and stability of the crucible, and reduce heat loss.
Smart Images
Figure CN223201895U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of evaporation technology, and in particular to a crucible for evaporation. Background Art
[0002] The current evaporation process is mainly achieved through rollers, crucibles and high-temperature polyester films. The high-temperature polyester film is attached to the roller, and a crucible is placed under the roller. The crucible is filled with metal evaporation material. The metal material evaporates after high-temperature heating, and the gaseous metal evaporates onto the high-temperature polyester film on the roller to achieve coating. The high-temperature polyester film can rotate with the roller to achieve continuous coating.
[0003] During the evaporation process, solid metal evaporation material is first added to the crucible, heated to liquid state, and then further heated to turn it into gaseous state, and attached to the high-temperature polyester film to complete the evaporation process. After each round of the process, the remaining metal evaporation material in the crucible will cool and become a whole solid block. At this time, compared with the first filling of solid metal evaporation material, the gap between the metal evaporation material and the crucible has changed. Since the thermal expansion coefficient of the metal is much higher than that of the crucible, the metal evaporation material will produce thermal expansion stress on the crucible during the next heating. In severe cases, it may even squeeze the crucible and cause the edge to break.
[0004] Therefore, the evaporation crucible has the problem that the residual metal evaporation material expands and squeezes the crucible when it is heated again. Utility Model Content
[0005] In order to alleviate the problem of thermal expansion and extrusion of the crucible caused by secondary heating of residual metal evaporation material, the present application provides a crucible for evaporation.
[0006] The present application provides a crucible for evaporation using the following technical solution:
[0007] A crucible for evaporation comprises a crucible side wall, a crucible bottom plate and a blocking member. There are a plurality of blocking members which are parallel to each other and evenly arranged on the crucible bottom plate.
[0008] By adopting the above technical solution, when the remaining metal evaporation material in the crucible is reheated, the blocking member of the crucible bottom plate will have a blocking effect on the thermal expansion of the metal evaporation material, thereby reducing its expansion tendency toward the side wall of the crucible and increasing its expansion tendency upward, thereby reducing the force exerted by the thermal expansion stress generated by the metal evaporation material on the side wall of the crucible, and reducing the risk of the metal evaporation material extruding and damaging the crucible due to thermal expansion.
[0009] Preferably, the blocking member is a protrusion, which is strip-shaped and has a semicircular cross-section.
[0010] By adopting this technical solution, the semicircular protrusion design allows it to evenly distribute force when subjected to pressure, reducing stress concentration. Compared with other protrusion shapes, the semicircular protrusion can better balance internal and external pressure, reduce local stress concentration, and thus improve the strength and stability of the protrusion.
[0011] Preferably, the blocking member is a baffle, which divides the crucible into multiple areas.
[0012] By adopting the above technical solution, when the remaining metal evaporation material in the crucible is heated for the second time, the metal evaporation material undergoes thermal expansion, and the baffle plays a role in suppressing the expansion of the metal, thereby reducing the force exerted on the side wall of the crucible by the thermal expansion stress generated by the metal evaporation material, and reducing the risk of the crucible being damaged by the thermal expansion of the metal evaporation material.
[0013] Preferably, the baffle is one third to one half of the height of the crucible side wall.
[0014] By adopting the above technical solution, the height of the baffle is limited, the pressure and dynamic load exerted by the metal vapor deposition material on the baffle are reduced, and the damage to the baffle caused by the thermal expansion of the metal vapor deposition material is reduced. Because the baffle is thin, it is easy to be damaged by the thermal expansion force of the metal vapor deposition material, and lose the function of suppressing metal expansion.
[0015] Preferably, the side walls of the crucible are arc-shaped and connected end to end.
[0016] By adopting the above technical solution, compared with the square crucible side wall, the square crucible side wall will cause local stress concentration at the four corners of the square, thereby reducing the overall bearing capacity. The curved crucible side wall has a more uniform force distribution, is less likely to deform when subjected to external pressure, and can better withstand internal or external pressure.
[0017] Preferably, the opening radius of the crucible side wall close to the crucible bottom plate is smaller than the opening radius away from the crucible bottom plate.
[0018] By adopting the above technical solution, the entire crucible is trumpet-shaped with a small bottom and a large top. Compared with the cylindrical shape, the structure has a more balanced strength distribution. The arc-shaped structure of the top and bottom of the crucible side wall can better withstand pressure, evenly disperse stress, and improve the strength and stability of the crucible.
[0019] Preferably, the blocking member is in a circular ring shape and is evenly fixed on the crucible bottom plate in the crucible.
[0020] By adopting the above technical solution, the blocking member is annular, and when the metal evaporation material in the crucible expands thermally, it can play a uniform blocking role and reduce the stress of the metal evaporation material on the side wall of the arc-shaped crucible.
[0021] Preferably, the crucible side wall includes an outer crucible wall and an inner crucible wall. The outer crucible wall is made of a material with high pressure resistance, and the inner crucible wall is made of a material with excellent lubricity to reduce adhesion and aggregation of the metal evaporation material and improve the fluidity of the metal evaporation material.
[0022] By adopting the above technical solution, the outer wall of the crucible has high strength and is capable of withstanding the thermal expansion force of the liquefied metal vapor deposition material inside. The inner wall of the crucible has excellent lubrication properties, reducing friction between the inner wall and the liquefied metal vapor deposition material. This can reduce the friction and adhesion of the liquefied metal vapor deposition material to the inner wall of the crucible, thereby reducing the magnitude of the thermal expansion pressure of the metal vapor deposition material.
[0023] Preferably, a thin heat-insulating layer is provided between the outer wall of the crucible and the inner wall of the crucible.
[0024] By adopting the above technical solution, the metal deposition material inside the crucible can be kept warm and insulated without affecting the heating and heat conduction of the crucible bottom plate, thereby effectively reducing heat loss.
[0025] Preferably, the connection between the crucible side wall and the crucible bottom plate is chamfered.
[0026] By adopting the above technical solution, the stress concentration at the connection between the crucible side wall and the crucible bottom plate can be effectively reduced, and the problem of cracking at the connection between the crucible side wall and the crucible bottom plate due to excessive stress of the metal evaporation material can be effectively alleviated.
[0027] In summary, this application includes at least one of the following beneficial technical effects:
[0028] 1. The thermal expansion stress of the metal evaporation material is partially offset by the inhibitory effect of the barrier provided on the bottom plate of the crucible, thereby reducing the force acting on the side wall of the crucible and lowering the risk of the metal evaporation material damaging the crucible due to thermal expansion and extrusion;
[0029] 2. By changing the shape and angle of the crucible side wall and setting up a double-layer structure, the bearing capacity of the crucible side wall is improved. BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Figure 1 It is a schematic diagram of the three-dimensional structure of Example 1.
[0031] Figure 2 It is a cross-sectional view of the crucible of Example 1 along the central axis.
[0032] Figure 3 It is a schematic diagram of the three-dimensional structure of Example 2.
[0033] Figure 4 It is a cross-sectional view of the crucible of Example 2 along the central axis.
[0034] Figure 5 It is a schematic diagram of the three-dimensional structure of Example 3.
[0035] Figure 6 It is a cross-sectional view of the crucible of Example 3 along the central axis.
[0036] 11. Crucible side wall; 111. Crucible outer wall; 112. Crucible inner wall; 12. Crucible bottom plate; 13. Protrusion; 14. Baffle. DETAILED DESCRIPTION
[0037] The following is combined with Figure 1-6 This application is described in further detail.
[0038] The embodiment of the present application discloses a crucible for evaporation.
[0039] Example 1
[0040] Reference Figure 1 A crucible for evaporation includes a crucible bottom plate 12, a crucible side wall 11 and a protrusion 13. The crucible for evaporation is a rectangular hollow structure with an open top. The material is isobaric graphite with a strength of 40-90Mpa. When in use, metal evaporation material is added to the crucible from the opening at the top of the crucible. The crucible is heated by a heating device to convert the metal evaporation material in the crucible from a solid state to a gaseous state. The gaseous metal evaporation material leaves the crucible opening and adheres to the high-temperature polyester film above the crucible to complete the evaporation process.
[0041] The crucible bottom plate 12 is provided with a plurality of protrusions 13, which are parallel to each other and are evenly fixed on the crucible bottom plate 12 in the crucible. Figure 2 The cross section of the protrusion 13 is semicircular and is fixed on the crucible bottom plate 12 in a strip-like shape at equal intervals. The semicircular protrusion 13 can evenly disperse the force when subjected to the thermal expansion stress of the metal evaporation material, reduce stress concentration, and enhance the mechanical properties of the protrusion 13. The radius size of the protrusion 13 depends on the size of the crucible.
[0042] refer to Figure 2The connection between the crucible side wall 11 and the crucible bottom plate 12 is chamfered, which can effectively reduce the stress concentration at the connection between the crucible side wall 11 and the crucible bottom plate 12. The crucible side wall 11 includes the crucible outer wall 111 and the crucible inner wall 112. The crucible inner wall 112 is in direct contact with the metal vapor deposition material and has excellent lubrication performance. It can reduce the friction between the crucible and the metal vapor deposition material, reduce the friction and adhesion of the metal vapor deposition material on the crucible inner wall 112, and thus reduce the pressure of the metal vapor deposition material on the crucible side wall 11 due to thermal expansion; the crucible outer wall 111 covers the crucible inner wall 112, has strong pressure resistance, and ensures that the crucible side wall 11 has sufficient bearing capacity. A thin thermal insulation layer is also provided between the crucible outer wall 111 and the crucible inner wall 112. Because it is very thin, it is not drawn in the figure. The thermal insulation layer has a thermal insulation effect on the metal vapor deposition material inside the crucible, which can effectively reduce heat loss.
[0043] The implementation principle of Example 1 is:
[0044] When the residual metal evaporation material in the crucible is heated for the second time and undergoes thermal expansion, the gap between the metal evaporation material and the crucible will change because the metal evaporation material in the crucible has already undergone a process of transformation from solid to liquid and then from liquid to solid. Therefore, when the metal evaporation material is further heated and expanded, due to the huge difference in thermal expansion coefficients between the metal evaporation material and the crucible material, the thermal expansion of the metal evaporation material will generate a great pressure on the crucible side wall 11.
[0045] The multiple protrusions 13 fixed on the bottom of the crucible will hinder the thermal expansion of the metal evaporation material residue, slow down the expansion trend of the metal evaporation material residue toward the crucible side wall 11, and promote the metal evaporation material residue to expand toward the upper opening of the crucible, thereby reducing the stress of the metal evaporation material residue on the crucible side wall 11.
[0046] Example 2
[0047] Reference Figure 3 The blocking member in this embodiment is a baffle 14, which is arranged inside the crucible and connected to the crucible side wall 11 and the crucible bottom plate 12. Figure 4In this embodiment, the height of the baffle 14 is set to be half the height of the crucible side wall 11. Multiple baffles 14 are fixed on the crucible bottom plate 12 in parallel with each other and at equal intervals, dividing the interior of the crucible into multiple small blocks. The connection between the crucible side wall 11 and the crucible bottom plate 12 is rounded, which can effectively reduce the stress concentration at the connection between the crucible side wall 11 and the crucible bottom plate 12. The crucible side wall 11 is a double-layer structure, including a crucible inner wall 112 and a crucible outer wall 111. The crucible outer wall 111 covers the crucible inner wall 112. The crucible inner wall 112 has good lubrication performance and the crucible outer wall 111 has a strong bearing capacity. A thin thermal insulation layer is also provided between the crucible outer wall 111 and the crucible inner wall 112. Because it is very thin, it is not drawn in the figure. The thermal insulation layer has a heat-insulating effect on the metal evaporation material inside the crucible, which can effectively reduce heat loss.
[0048] The implementation principle of Example 2 is:
[0049] The baffle 14 divides the interior of the crucible into a plurality of small blocks. When the residual metal evaporation material in the crucible undergoes thermal expansion during secondary heating, the baffle 14 acts as the crucible side wall 11 for the metal evaporation material in each small block, thereby blocking the thermal expansion of the metal evaporation material in the small block. This prevents the expansion of the residual metal evaporation material toward the crucible side wall 11, offsets part of the thermal expansion stress of the residual metal evaporation material in the small block, and causes the metal evaporation material in the small block to expand toward the upper opening of the crucible as much as possible. The crucible side wall 11 mainly bears the thermal expansion stress of the metal evaporation material in the small block close to the crucible side wall 11, thereby reducing the thermal expansion stress of the residual metal evaporation material on the crucible side wall 11, thereby reducing the risk of the crucible being broken by the expansion and extrusion of the residual metal evaporation material.
[0050] The height of baffle 14 is designed to be half the height of the crucible's inner sidewall 112 to ensure structural stability. Setting a baffle too high would cause the liquid metal to flow violently and accumulate within the container, increasing the pressure and dynamic load on the baffle. This could lead to deformation, cracking, or instability of the baffle, increasing the container's instability. Furthermore, because baffle 14 is very thin and has limited load-bearing capacity, a baffle 14 that is too high could easily break when subjected to thermal expansion stress, thereby losing its decompression effect on the crucible's sidewall 11. This design also reduces the adhesion of gaseous metal evaporation material, improving its utilization rate.
[0051] The good lubrication performance of the inner wall 112 of the crucible reduces the friction between it and the liquefied metal evaporation material, reduces the friction and adhesion of the liquefied metal evaporation material on the inner wall 112 of the crucible, and reduces the pressure on the side wall 11 of the crucible. The outer wall 111 of the crucible has a strong bearing capacity, ensuring the overall bearing strength of the crucible.
[0052] Example 3
[0053] Reference Figure 5In this embodiment, the crucible is a trumpet-shaped structure with an upper opening, the upper opening is larger than the lower opening, and the blocking member in the crucible is a protrusion 13. Figure 6 The protrusions 13 are multiple circular protrusions 13 of varying sizes. The protrusions 13 are fixed to the crucible bottom plate 12 at equal intervals with the geometric center of the crucible bottom plate 12 as the axis. The connection between the crucible side wall 11 and the crucible bottom plate 12 is rounded, which can effectively reduce the stress concentration at the connection between the crucible side wall 11 and the crucible bottom plate 12. The crucible side wall 11 is a double-layer structure, including a crucible inner wall 112 and a crucible outer wall 111. The crucible outer wall 111 covers the crucible inner wall 112. The crucible inner wall 112 has good lubrication performance and the crucible outer wall 111 has a strong load-bearing capacity. A thin thermal insulation layer is also provided between the crucible outer wall 111 and the crucible inner wall 112. Because it is very thin, it is not drawn in the figure. The thermal insulation layer has a heat-insulating effect on the metal evaporation material inside the crucible, which can effectively reduce heat loss.
[0054] The implementation principle of Example 3 is:
[0055] The arc-shaped crucible side wall 11 is matched with multiple annular protrusions 13. When the metal vapor deposition material inside the crucible expands thermally and is squeezed toward the crucible side wall 11, the protrusions 13 fixed on the crucible bottom plate 12 will hinder the expansion of the metal vapor deposition material toward the surrounding crucible side walls 11. Cooperating with the action of the crucible bottom plate 12, the metal vapor deposition material is expanded as much as possible toward the opening of the crucible, thereby reducing the squeezing effect on the crucible side wall 11 and preventing the crucible side wall 11 from being damaged by excessive squeezing stress of the metal vapor deposition material.
[0056] The above are all preferred embodiments of the present application, and are not intended to limit the scope of protection of the present application. Therefore, any equivalent changes made based on the structure, shape, and principle of the present application should be included in the scope of protection of the present application.
Claims
1. A crucible for evaporation, characterized in that: The invention comprises a crucible side wall (11), a crucible bottom plate (12) and a blocking member, wherein the blocking member is provided in plurality and is parallel to each other and evenly fixed on the crucible bottom plate (12); the crucible side wall (11) is arc-shaped and connected end to end; the opening radius of the crucible side wall (11) close to the crucible bottom plate (12) is smaller than the opening radius away from the crucible bottom plate (12); the blocking member is annular and evenly fixed on the crucible bottom plate (12) in the crucible; the crucible side wall (11) comprises a crucible outer wall (111) and a crucible inner wall (112); the crucible outer wall (111) is made of a pressure-resistant material, and the crucible inner wall (112) is made of a lubricating material to reduce the adhesion and cohesion of the metal evaporation material and improve the fluidity of the metal evaporation material; a thin heat-insulating layer is also provided between the crucible outer wall (111) and the crucible inner wall (112).
2. The evaporation crucible according to claim 1, characterized in that: The connection between the crucible side wall (11) and the crucible bottom plate (12) is rounded.