Evaporation boat

Abstract

The utility model discloses an evaporation boat, which belongs to the technical field of vacuum evaporation and comprises a boat body, a first clamping end and a second clamping end are arranged at two longitudinal ends of the boat body; the molten pool is arranged in an evaporation area formed on the upper side surface of the boat body; wherein a plurality of heating areas with groove depths gradually increased in a gradient manner are arranged in the molten pool towards the two ends of the boat body in the longitudinal direction corresponding to the wire feeding site. According to the evaporation boat structure, the heating area structure with specific height difference is arranged, and the sectional area, perpendicular to the longitudinal direction, of the heating area close to the end side is small, so that the evaporation boat structure has a relatively large resistance value, heat loss close to the end side can be compensated, and the boat body has relatively uniform temperature; and meanwhile, due to the fact that the stepped arrangement structure from high to low is formed, the molten metal can be spread towards the two sides easily, and the evaporation area is increased.

Description

Technical Field

[0001] The utility model relates to the technical field of vacuum evaporation, in particular to an evaporation boat. Background Art

[0002] So-called vacuum belt metallization using PVD (physical vapor deposition) is a common method for coating flexible substrates with metals. For example, the flexible substrate can be a plastic film, a metal foil, a film or paper. The most commonly used metal for coating the substrate is aluminum.

[0003] In order to generate metal vapor, an evaporation boat is usually used. Existing evaporation boats are generally boat-shaped structures. In a vacuum environment, these evaporation boats are heated by direct passage of electric current. A metal wire such as aluminum is guided to the middle of the preheated evaporation boat. After the metal wire melts, it vaporizes to form metal vapor and adheres to the surface of the substrate.

[0004] However, since the evaporation boat is in direct contact with the electrode, and the electrode is generally equipped with a water cooling device, the temperature on both sides of the evaporation boat will be significantly lower than that in the middle, which will affect the evaporation rate of the molten metal at the ends of the evaporation boat, and the molten metal will easily overflow from the ends. Therefore, the heating power is generally increased appropriately (voltage / current is adjusted), which will undoubtedly accelerate the corrosion of the evaporation boat.

[0005] To solve the above problems, in the prior art, the cross-section perpendicular to the length direction of the evaporation boat body along the two ends of the evaporation boat gradually becomes smaller to gradually increase the temperature on both sides, thereby reducing the problem of accumulation and overflow of molten metal in the evaporation boat.

[0006] By reducing the transverse cross-sectional area, the strength of the evaporation boat will be greatly reduced, and there is a risk of cracks or breakage in the vacant area due to the reduced area at high temperatures. Utility Model Content

[0007] The utility model aims to solve one of the technical problems in the related art at least to a certain extent. To this end, one purpose of the utility model is to provide an evaporation boat that can ensure strength and temperature uniformity and increase the wetting and dispersion of the metal liquid on the evaporation surface.

[0008] The technical solution of the utility model is as follows:

[0009] An evaporation boat comprises: a boat body, with a first clamping end and a second clamping end disposed at both ends in the longitudinal direction;

[0010] The molten pool is arranged in the evaporation zone formed on the upper surface of the boat body; wherein, corresponding to the wire feeding position, a plurality of heating zones with increasing groove depth gradient are arranged in the molten pool along the longitudinal direction toward the two ends of the boat body.

[0011] Based on the above technical solution, a heating zone structure with a specific height difference is set, and the cross-sectional area of ​​the heating area near the end side is small perpendicular to the longitudinal direction, so it has a relatively larger resistance value, thereby being able to compensate for the heat loss near the end side, so that the boat body has a relatively uniform temperature; at the same time, due to the formation of a stepped arrangement structure from high to low, it is beneficial for the molten metal to spread to both sides, thereby increasing the evaporation area.

[0012] Further, the depth of the molten pool is set to 0.5-5 mm.

[0013] Based on the above technical solution and appropriate evaporation boat specifications, the molten pool depth is controlled to meet the requirements of different process routes.

[0014] Furthermore, a guide portion is provided at the connection between adjacent heating zones.

[0015] Based on the above technical solution, a guide portion is provided to allow the molten metal to flow slowly, thereby reducing the impact of the molten metal.

[0016] Furthermore, the cross-sectional shape of the guide portion is set to be an inclined surface and / or a curved surface.

[0017] Based on the above technical solution, it is convenient to process the guide part.

[0018] Furthermore, the heating zones divide the molten pool into at least three groups.

[0019] Based on the above technical solution, the heating zones are set into multiple groups, which subdivide the molten pool into heating zones with different depths, reduce the height difference between adjacent heating zones, and reduce the impact caused by the spreading flow of the molten metal.

[0020] Furthermore, the heating zones are symmetrically arranged in the molten pool.

[0021] Based on the above technical solution, the temperature in the molten pool is relatively uniform.

[0022] Furthermore, there is a height difference between the starting end and the ending end of the adjacent next-level heating zone, and the height of the ending end is higher than the starting end and does not exceed the height of the ending end of the adjacent previous level.

[0023] Based on the above technical solution, the height of the heating zones at the same level is increased gradually, which can reduce the speed at which the molten metal flows toward the heating zone at the next level to a certain extent, thereby fully heating the molten metal.

[0024] Furthermore, the heating zone is configured as a smooth, upwardly inclined slope structure.

[0025] Based on the above technical solution, it is beneficial for the metal liquid to flow and infiltrate, and convenient for processing.

[0026] Furthermore, the heating zone has an upward inclination angle with the longitudinal direction of the boat body, and the inclination angle does not exceed 3°.

[0027] Based on the above technical solution, the flow rate of the molten metal is slowed down without substantially affecting the temperature compensation of the heating zone.

[0028] Furthermore, a recess is provided at the bottom of the boat body corresponding to the next-level heating zone.

[0029] Based on the above technical solution, the maximum depth of the upper molten pool can be reduced, thereby reducing the groove depth of the upper part of the boat body to a certain extent, and improving the problem of stress concentration and cracking caused by thermal expansion.

[0030] Further, the recesses are arranged in a plurality of spaced groups.

[0031] Based on the above technical scheme, in addition to avoiding serious material reduction and lower strength of the upper part of the boat body caused by setting up multiple heating zones with increasing depths, an I-shaped structure can also be formed at the corresponding adjacent recesses at the bottom of the boat body to better disperse the load and reduce stress concentration. In combination with the heating zone with a relatively shallow groove depth above the boat body, the strength can be increased to a certain extent.

[0032] Furthermore, the depth dimension of the recess matches the depth difference between the corresponding heating zone and the previous heating zone.

[0033] Based on the above technical solution, the loss of heating power can be compensated more accurately.

[0034] Further, the depth of the recess increases linearly toward the end side of the boat body, and / or the recess matches the length of the heating zone.

[0035] Based on the above technical solution, the resistance value can be accurately adjusted. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0037] Figure 1 It is a schematic diagram of the structure of the boat body;

[0038] Figure 2 for Figure 1 A schematic cross-sectional structure diagram of ;

[0039] Figure 3 for Figure 1 A schematic diagram of a top view structure;

[0040] Figure 4 It is a structural schematic diagram of the first improved solution for the boat body;

[0041] Figure 5It is a structural schematic diagram of the second improved solution for the boat body;

[0042] Figure 6 It is a structural schematic diagram of the third improved solution for the boat body;

[0043] Figure 7 It is a structural schematic diagram of the fourth improved solution for the boat body;

[0044] Figure 8 for Figure 7 A schematic diagram of the structure of the bottom of the mid-boat body;

[0045] Fig. 9 It is a structural schematic diagram of the fifth improvement scheme of the boat body;

[0046] Fig.10 for Fig. 9 Schematic diagram of the structure of the bottom of the mid-boat body.

[0047] In the figure: 1-boat body; 11-molten pool; 111-first zone; 112-second zone; 113-third zone; 114-fourth zone; 12-flow guide; 13-recess; 131-first recess; 132-second recess. DETAILED DESCRIPTION

[0048] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0049] Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0050] Reference Figure 1-3 , an evaporation boat, comprising:

[0051] The boat body 1 has a first clamping end and a second clamping end at both ends of the boat body 1 in the longitudinal direction (corresponding to the current direction), which are used to contact and electrically conduct with the electrode. The cross-sectional shape of the first clamping end and the second clamping end is a polygon, such as a rectangle, or a trapezoid, a regular polygon, etc.; its shape structure should match the electrode clamping end, such as being arranged in a stepped shape, etc.;

[0052] The molten pool 11 is arranged in the evaporation zone formed on the upper surface of the boat body 1 and is a groove-shaped structure; of course, the evaporation zone is not limited to the groove formed on the evaporation side, and the outer edge of the groove should also be considered as the evaporation zone; the depth of the molten pool is selected in combination with the wire feeding amount and the adaptability of the evaporation boat size, and is generally set to 0.5-5mm, and its length is also set as needed;

[0053] Among them, corresponding to the wire feeding position, a plurality of heating zones with increasing groove depth gradients are arranged in the molten pool 11 along the longitudinal direction toward the two ends of the boat body 1.

[0054] A heating zone structure with a specific height difference is set, and the cross-sectional area of ​​the area near the end side perpendicular to the longitudinal direction is small, so it has a relatively larger resistance value, which can compensate for the heat loss near the end side, thereby making the boat body have a relatively uniform temperature; in addition, due to the formation of a stepped structure, it is beneficial for the molten metal to spread to both sides, thereby increasing the evaporation area.

[0055] Considering that the wire feeding point is generally set in the middle of the boat body, the heating zones are basically symmetrically distributed, including the first zone 111, the second zone 112, the third zone 113 and the fourth zone 114 which are connected in sequence from the middle of the molten pool 11 to the end side, wherein the groove depths from the first zone 111 to the fourth zone 114 increase step by step; the surface height of the first zone 111 is slightly lower than the height of the molten pool 11 (such as 0.1 mm, which can be set according to actual conditions) to avoid overflow of molten metal.

[0056] like Figure 4 Considering the transition at the connection between adjacent heating zones, a guide portion 12 is further provided at the connection between adjacent heating zones so that the molten metal can flow slowly; the cross-sectional shape of the guide portion 12 can be set to an inclined surface and / or an arc surface to reduce the impact that may be caused when the molten metal falls along the vertical step wall, thereby reducing aluminum splashing and corrosion at the site to a certain extent.

[0057] like Figure 5 The main difference is that the heating zone divides the molten pool 1 into 7 groups with the same longitudinal length; the heating zones are set into multiple groups, which can subdivide the molten pool 1 into heating zones with different depths, reduce the height difference between adjacent heating zones, and reduce the impact caused by the spreading flow of the molten metal liquid.

[0058] Reference Figure 6 There is a height difference between the starting end and the ending end of the second zone 112 and the third zone 113. The height of the ending end is higher than the starting end and does not exceed the height of the end of the previous level. They have upward inclination angles α and β with the longitudinal direction of the boat body, respectively. The inclination angles α and β are preferably not more than 3°. In this way, an upwardly inclined heating zone structure is formed, which can reduce the speed of the molten metal flowing toward the next level heating zone to a certain extent, and thus can fully heat the molten metal.

[0059] Further references Figure 7and Figure 8 , the boat body 1 is provided with a recess 13 at the bottom position corresponding to the fourth zone 114. At this time, the fourth zone 114 is flush with the third zone 113, which reduces the maximum depth of the upper molten pool, i.e., D2 ( Figure 7 The depth of the third zone) is less than D1 ( Figure 6 In this way, the groove depth of the upper part of the boat body can be reduced to a certain extent, and the problem of stress concentration and cracking caused by thermal expansion can be improved.

[0060] The size of the recess 13 matches the depth difference between the fourth zone 114 and the third zone 113 to appropriately increase the resistance and compensate for the loss of heating power; of course, considering linear compensation, the depth of the recess 13 increases linearly toward the end of the boat body, that is, the bottom of the recess is inclined; the recess 13 can also match the length of the heating zone to reduce the depth of the recess and the upper heating zone as a whole, and also avoid the problem of stress concentration to a certain extent.

[0061] Reference Figure 9-10 , and Figure 7-8 The main difference is that the recess includes a first recess 131 and a second recess 132 which are arranged at intervals, and the first recess 131 and the second recess 132 are correspondingly arranged on the longitudinal outer sides of the corresponding heating zones, and the depth of each recess is adaptively arranged to the position of the corresponding heating zone, that is, it is adapted to the depth of the corresponding heating zone to compensate for the temperature loss caused by being close to the end side of the boat body 1.

[0062] The recesses arranged at intervals in this way can not only avoid serious material reduction in the upper part of the boat body and lower strength of the upper part caused by setting multiple heating zones with increasing depths, but also form an I-shaped structure at the bottom of the boat body 1 corresponding to the recesses 131 and 132, which can better disperse the load and reduce stress concentration. In combination with the heating zone with a relatively shallow groove depth above the boat body, the strength can be increased to a certain extent.

[0063] Of course, it can also be configured as multiple intervals, based on the number of heating zones and the adaptability of the positions, and the recessed portion close to the end side of the boat body 1 has a relatively larger recessed depth.

[0064] The material of the boat body is conventional material of commercially available evaporation boats, such as graphite, ceramic or metal (tungsten, molybdenum, etc.) materials.

[0065] In the present application, structures and connection relationships that are not described in detail are all prior arts, and their structures and principles are well-known technologies and will not be repeated here; for example, the material of the boat body and the limitation of related dimensional parameters can be selected according to actual needs.

[0066] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0067] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An evaporation boat, comprising: The boat body has two longitudinal ends provided with a first clamping end and a second clamping end; The molten pool is arranged in the evaporation zone formed on the upper surface of the boat body; it is characterized in that a plurality of heating zones with increasing groove depth gradients are arranged longitudinally in the molten pool corresponding to the wire feeding positions toward the two ends of the boat body.

2. The evaporation boat according to claim 1, characterized in that: The heating zones divide the molten pool into at least three groups, and / or the depth of the molten pool is set to 0.5-5 mm.

3. The evaporation boat according to claim 1, characterized in that: A flow guide is provided at the connection between adjacent heating zones.

4. The evaporation boat according to claim 1, characterized in that: The heating zones are symmetrically arranged in the molten pool.

5. The evaporation boat according to any one of claims 1 to 4, characterized in that: There is a height difference between the starting end and the ending end of the adjacent next-level heating zone, and the height of the ending end is higher than the starting end and does not exceed the height of the ending end of the adjacent previous level.

6. The evaporation boat according to claim 5, characterized in that: The heating zone is arranged as a smooth, upward sloping ramp structure.

7. The evaporation boat according to claim 6, characterized in that: The inclination angle of the heating zone does not exceed 3°.

8. The evaporation boat according to any one of claims 1-4, 6-7, characterized in that: A recess is provided at the bottom of the boat body corresponding to the next-level heating zone.

9. The evaporation boat according to claim 8, characterized in that: The recesses are arranged in a plurality of spaced groups.

10. The evaporation boat according to claim 9, characterized in that: The depth of the concave portion matches the depth difference between the corresponding heating zone and the previous heating zone; And / or, the recess matches the length of the heating zone.

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