Chromium evaporation device for preparing chromium film through electron beam evaporation

Abstract

The utility model relates to the technical field of vacuum coating, in particular to a chromium evaporation device for preparing a chromium film through electron beam evaporation, which comprises a crucible and an ingot, one side of the crucible is provided with a concave evaporation cavity, and the inner bottom wall of the evaporation cavity is constructed to be a material placing plane for providing a placing surface for the ingot. A first placing plane parallel to the material placing plane is formed on one side, opposite to the side surface provided with the evaporation cavity, of the crucible. According to the chromium evaporation device for preparing the chromium film through electron beam evaporation, a thin-layer air gap is formed between the ingot and the crucible by forming the inwards-concave embedding groove in the second placement plane of the ingot, so that the speed of heat conducted to the ingot from the crucible is reduced, heat conduction can be more uniform through the gap, and the heat transfer efficiency is improved. Therefore, uniform heating of the ingot in the evaporation process is guaranteed, the problem that the overall evaporation rate of the ingot is unstable due to local overheating of the ingot is solved, and the effect of improving coating completeness and smoothness is achieved.

Description

Technical Field

[0001] The utility model relates to a chromium evaporation device, in particular to a chromium evaporation device used for preparing chromium film by electron beam evaporation. Background Art

[0002] Conventional electron beam evaporation equipment for preparing chromium films usually includes a crucible and a chromium ingot, wherein the crucible is used to hold the chromium ingot, and the chromium ingot is heated by an electron beam to evaporate it, so as to form a chromium film on the surface of the product.

[0003] However, in actual applications, it was found that the chromium ingot was in direct contact with the bottom of the crucible, and the heat conduction path was short and direct, which could easily lead to local overheating and affect the quality of the final chromium film. Utility Model Content

[0004] The utility model aims to provide a chromium evaporation device for preparing chromium film by electron beam evaporation, so as to slow down the speed of heat conduction from the crucible to the ingot and make the heat conduction more uniform. The design overcomes the problem of unstable evaporation rate caused by local overheating of the ingot in the prior art, and significantly improves the integrity and smoothness of the coating.

[0005] The technical solution adopted by the utility model to solve the above problems is: a chromium evaporation device for preparing chromium film by electron beam evaporation, comprising:

[0006] A crucible, wherein one side of the crucible is configured with an inwardly concave evaporation chamber, the inner bottom wall of the evaporation chamber is configured as a loading plane, the side of the crucible opposite to the side provided with the evaporation chamber is configured with a first placement plane, the first placement plane is arranged parallel to the loading plane, and the loading plane is perpendicular to the extension direction of the evaporation chamber.

[0007] The ingot comprises an evaporation plane, a second placement plane parallel to the evaporation plane and a peripheral outer wall arranged perpendicular to the second placement plane. The ingot is placed in the evaporation chamber, and the second placement plane is in contact with the material placement plane. The second placement plane side is configured with a concave fitting groove.

[0008] Preferably, a peripheral edge of the evaporation plane is configured with an annular embedding groove to form a step structure, and the step structure forms a platform by cooperating with the protruding evaporation plane.

[0009] Preferably, the engaging groove consists of a peripheral inner wall and an inner top wall, the inner top wall is arranged parallel to the evaporation plane, and the inner top wall is perpendicular to the peripheral inner wall, and the distance between the peripheral inner wall and the peripheral outer wall is set to a preset value.

[0010] Preferably, the distance between the peripheral side of the platform and the peripheral side outer wall is also the preset value.

[0011] Preferably, the ingot is in the shape of a cylinder, the height of the cylinder is any value between 5 mm and 15 mm, and the diameter of the cylinder is any value between 25 mm and 35 mm.

[0012] Preferably, the surface roughness of the evaporation plane is less than 1.6 micrometers.

[0013] Preferably, the crucible is made of oxygen-free copper / molybdenum material.

[0014] Beneficial effects of the embodiments of the present invention

[0015] The chromium evaporation device for preparing chromium film by electron beam evaporation forms a thin air gap between the ingot and the crucible by constructing an inwardly concave interlocking groove on the second placement plane of the ingot, so as to slow down the speed of heat conduction from the crucible to the ingot. Moreover, the air gap can make the heat conduction more uniform, thereby ensuring that the ingot is heated uniformly during the evaporation process, overcoming the problem of unstable overall evaporation rate of the ingot caused by local overheating of the ingot, and achieving the effect of improving the integrity and smoothness of the coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a front cross-sectional view of a chromium evaporation device used for preparing a chromium film by electron beam evaporation in an embodiment of the utility model.

[0017] Figure 2 It is a front cross-sectional view of adjacent ingots in an embodiment of the utility model in a superimposed state.

[0018] Figure 3 It is a stereoscopic view of a chromium evaporation device used for preparing a chromium film by electron beam evaporation in an embodiment of the utility model.

[0019] Among them: 100, crucible; 110, evaporation chamber; 111, material placement plane; 120, first placement plane; 200, ingot; 210, evaporation plane; 211, step structure; 220, second placement plane; 221, fitting groove; 2211, peripheral inner wall; 2212, inner top wall; 230, peripheral outer wall; 240, table body. DETAILED DESCRIPTION

[0020] The specific implementation methods of the present application are further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present application but are not intended to limit the scope of the present application.

[0021] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the scope of protection of the present application. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description created by the present application, unless otherwise specified, "multiple" means two or more.

[0022] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood by specific circumstances.

[0023] See also Figure 1-Figure 2. The present embodiment provides a chromium evaporation device for preparing chromium film by electron beam evaporation, comprising a crucible 100 and an ingot 200. Among them, a concave evaporation chamber 110 is constructed on one side of the crucible 100, and the inner bottom wall of the evaporation chamber 110 is constructed as a loading plane 111 to provide a placement position for the ingot 200. A first placement plane 120 is constructed on the side of the crucible 100 opposite to the side with the evaporation chamber 110, and the first placement plane 120 is arranged parallel to the loading plane 111, and the loading plane 111 is perpendicular to the extension direction of the evaporation chamber 110, that is, the first placement plane 120 is perpendicular to the extension direction of the evaporation chamber 110, so that after the crucible 100 is placed on a plane parallel to the horizontal plane, the first placement plane 120 is in contact with the plane, and the loading plane 111 is parallel to the plane, so as to prevent the ingot 200 in the evaporation chamber 110 from sliding on the loading plane 111. The ingot 200 includes an evaporation plane 210, a second placement plane 220 parallel to the evaporation plane 210, and a peripheral outer wall 230 arranged perpendicular to the second placement plane 220. The ingot 200 is placed in the evaporation chamber 110, the second placement plane 220 is in contact with the loading plane 111, and a concave fitting groove 221 is constructed on the side of the second placement plane 220. The chromium evaporation device for preparing chromium film by electron beam evaporation forms a thin air gap between the ingot 200 and the crucible 100 by constructing a concave fitting groove 221 on the second placement plane 220 of the ingot 200. Since the thermal conductivity of air is much lower than that of metal, the gap can effectively slow down the speed at which heat is conducted from the crucible 100 to the ingot 200, and make the heat conduction more uniform, so as to ensure that the ingot 200 is evenly heated during the evaporation process, thereby overcoming the problem of unstable overall evaporation rate of the ingot 200 caused by local overheating of the ingot 200. Moreover, the uniform evaporation process of the ingot 200 also reduces pinholes and other defects caused by overheating or uneven heating, thereby improving the integrity and smoothness of the coating.

[0024] See also Figure 3 Specifically, the shape of the crucible 100 is approximately bowl-shaped, the evaporation chamber 110 is configured at the mouth of the bowl, the first placement plane 120 is located at the bottom of the bowl, and the material placement plane 111 is the inner wall of the evaporation chamber 110 close to the first placement plane 120 .

[0025] See also Figure 2Specifically, the evaporation plane 210 is arranged in parallel with the second placement plane 220, the peripheral outer wall 230 of the ingot 200 is located between the evaporation plane 210 and the second placement plane 220, the end of the peripheral outer wall 230 away from the second placement plane 220 is connected to the evaporation plane 210, the side of the peripheral outer wall 230 away from the evaporation plane 210 is connected to the second placement plane 220, and the peripheral outer wall 230 is connected end to end to form the outer surface of the ingot 200 through the evaporation plane 210, the second placement plane 220 and the peripheral outer wall 230. The fitting groove 221 is composed of a peripheral inner wall 2211 and an inner top wall 2212, the peripheral inner wall 2211 and the inner top wall 2212 are arranged vertically, and the inner top wall 2212 is parallel to the evaporation plane 210, and in some embodiments, the preset value is determined according to the actual size of the ingot 200.

[0026] In some embodiments, the ingot 200 is shaped like a cylinder, and in order to cooperate with a conventional crucible 100 for evaporation coating, the height of the cylinder is usually any value between 5 mm and 15 mm, and the diameter of the cylinder is usually any value between 25 mm and 35 mm.

[0027] In some embodiments, the peripheral edge of the evaporation plane 210 is configured with an annular embedding groove to form a step structure 211, and the step structure 211 forms a platform 240 by cooperating with the protruding evaporation plane 210. In some embodiments, the profile shape of the platform 240 observed from the cross section is the same as the profile shape of the ingot 200 observed from the cross section, and the distance between the peripheral side of the platform 240 and the peripheral side outer wall 230 and the distance between the peripheral side inner wall 2211 and the peripheral side outer wall 230 are both a certain preset value, so that the platform 240 on the ingot 200 can be embedded in the embedding groove 221 on the adjacent ingot 200 arranged in a stacked manner, and the peripheral side of the platform 240 is in contact with the peripheral side inner wall 2211 of the adjacent ingot 200, so that the adjacent ingots 200 stacked are automatically centered, thereby ensuring that the adjacent ingots 200 can be stably stacked together, and the peripheral sides of the adjacent ingots 200 are aligned so that the stacked ingots 200 can evaporate in an orderly manner. In one embodiment, the platform 240 is a truncated cone structure, the engaging groove 221 is a truncated cone-shaped groove, and the axis of the truncated cone structure is colinear with the axis of the truncated cone-shaped groove and passes through the center of the ingot 200 .

[0028] It should be noted that the cross section of the platform 240 and the cross section of the ingot 200 are both planes perpendicular to the thickness direction of the ingot 200 .

[0029] In some embodiments, the ingot 200 is a chromium ingot, the material purity of the chromium ingot should be greater than 99.95%, the content of oxygen in the material impurities should be less than 300 ppm, the content of iron should be less than 200 ppm, and the material density of the chromium ingot is any value between 7.1 g / cm3 and 7.2 g / cm3. It should be noted that the surface roughness of the evaporation plane 210 on the chromium ingot should be less than 1.6 microns.

[0030] Among them, the surface flatness of the evaporation plane 210 of the chromium ingot is less than 1.6 microns, so that during the evaporation process of the chromium ingot, the smooth evaporation plane 210 can evenly absorb and conduct heat, avoiding local overheating or overcooling, and the uniform heat conduction ensures that the chromium ingot can stably and evenly release chromium atoms throughout the evaporation process, thereby maintaining a stable evaporation rate. At the same time, the high-flatness evaporation plane 210 can ensure uniform evaporation of the chromium ingot surface, avoid uneven evaporation caused by uneven surface, and reduce the release of impurities. During the evaporation process, the uneven surface may cause some areas to evaporate too quickly due to uneven heating, generating gas or tiny particles, which will affect the stability of the vacuum environment. Moreover, since the chromium atoms are released evenly during the evaporation process, the thin film layer finally formed on the substrate will also be more uniform and dense, and the high-flatness evaporation plane 210 ensures the stability of the entire coating process, thereby improving the mechanical properties and smoothness of the film. In summary, when the surface flatness of the evaporation plane 210 of the chromium ingot is less than 1.6 microns, the vacuum phenomenon during chrome coating can be significantly improved.

[0031] In actual production, under reasonable vacuum coating process conditions, a single layer of chromium metal layer with a thickness of 300nm is evaporated on a clean glass substrate. After the coating is completed, it is checked with a strong light and a 20x magnifying glass. No pinholes are found in an area with a diameter of 1 inch.

[0032] Furthermore, the evaporation device in the present application, through the coordination of material density, surface flatness, material purity and the interlocking groove 221 constructed on the side of the second placement plane 220 of the ingot 200, makes the evaporation rate of the chromium ingot in the crucible 100 stable, and the single-pot material is resistant to evaporation, ensuring that a piece of chromium ingot can stably evaporate a coating with a thickness of 2 to 5 microns and form a dense and smooth coating layer, which significantly improves the quality and effect of the coating.

[0033] The material density refers to the mass per unit volume, which reflects the density of the material. For chromium ingots, the density is 7.1g / cm 3 Up to 7.2g / cm 3Between, it means that the internal structure of the material is tight, with fewer internal voids and defects. The material density in this range can ensure that the chromium ingot has better physical stability and consistency during production and use. Specifically, it can make the chromium ingot have better uniform thermal conductivity, stable evaporation rate and reduced evaporation defects. There are very few voids and defects inside the material, and heat can be evenly transferred to the entire chromium ingot, thereby avoiding local overheating or underheating. Moreover, the dense material can stably release chromium atoms when heated, avoiding uneven evaporation caused by internal voids or defects.

[0034] The material purity of chromium ingot is greater than 99.95%, which can significantly reduce the pollution and defects caused by impurities during the evaporation process. The higher the purity, the purer the evaporated chromium atoms, the denser and smoother the formed coating layer, and the more stable the physical and chemical properties.

[0035] The surface flatness of the evaporation plane 210 of the chromium ingot is less than 1.6 microns, so that during the evaporation process of the chromium ingot, the smooth evaporation plane 210 can evenly release chromium atoms, avoiding local heat concentration and uneven evaporation caused by surface unevenness, thereby ensuring the stability of the evaporation rate.

[0036] Furthermore, on the basis of the above-mentioned chromium ingot, electron beam evaporation technology and oxygen-free copper / molybdenum crucible 100 are used. The evaporation device can form a chromium plating layer that is denser and has a smoother surface than other evaporation processes. This is because the high-density and high-purity chromium ingot material, after fine machining, surface treatment and precise thermal control design, then the combined action of electron beam evaporation technology and oxygen-free copper / molybdenum crucible 100 ensures that chromium atoms are uniformly released during the evaporation process to form a uniform, dense and smooth film layer. These optimized process conditions significantly improve the quality of the chromium plating layer, which performs better than other evaporation processes.

[0037] Among them, the electron beam evaporation technology can accurately control the energy input so that the chromium ingot maintains a stable temperature during the evaporation process. This precise control helps to form a uniform chromium atomic flow and avoid unevenness and defects in the film layer. In addition, the electron beam evaporation is carried out in a high vacuum environment, which reduces the impact of ambient gas on the evaporation process, and the formed film is purer and denser. The crucible 100 made of oxygen-free copper / molybdenum material has good thermal conductivity, can quickly conduct heat, and ensure that the chromium ingot is evenly heated. At the same time, the oxygen-free copper / molybdenum material has good stability at high temperatures and will not introduce impurities.

[0038] The above contents described in this specification are merely examples of the present utility model. Those skilled in the art of the present utility model may make various modifications or additions to the specific embodiments described, or replace them in similar ways, as long as they do not deviate from the contents of the present utility model specification or exceed the scope defined in the claims, they shall all fall within the protection scope of the present utility model.

Claims

1. A chromium evaporation device for preparing a chromium film by electron beam evaporation, characterized in that: include: A crucible, wherein one side of the crucible is configured with an inwardly concave evaporation chamber, the inner bottom wall of the evaporation chamber is configured as a loading plane, the side of the crucible opposite to the side provided with the evaporation chamber is configured with a first placement plane, the first placement plane is arranged parallel to the loading plane, and the loading plane is perpendicular to the extension direction of the evaporation chamber; The ingot comprises an evaporation plane, a second placement plane parallel to the evaporation plane and a peripheral outer wall arranged perpendicular to the second placement plane. The ingot is placed in the evaporation chamber, and the second placement plane is in contact with the material placement plane. The second placement plane side is configured with a concave fitting groove.

2. A chromium evaporation device for preparing chromium film by electron beam evaporation according to claim 1, characterized in that: The peripheral edge of the evaporation plane is configured with an annular embedding groove to form a step structure, and the step structure forms a platform by cooperating with the protruding evaporation plane.

3. A chromium evaporation device for preparing a chromium film by electron beam evaporation according to claim 2, characterized in that: The engaging groove is composed of a peripheral inner wall and an inner top wall, the inner top wall is arranged parallel to the evaporation plane, and the inner top wall is perpendicular to the peripheral inner wall, and the distance between the peripheral inner wall and the peripheral outer wall is set to a preset value.

4. The chromium evaporation device for preparing chromium film by electron beam evaporation according to claim 3, characterized in that: The distance between the peripheral side of the platform and the peripheral side outer wall is also the preset value.

5. A chromium evaporation device for preparing a chromium film by electron beam evaporation according to any one of claims 1 to 4, characterized in that: The ingot is in the shape of a cylinder, the height of the cylinder is any value from 5 mm to 15 mm, and the diameter of the cylinder is any value from 25 mm to 35 mm.

6. The chromium evaporation device for preparing chromium film by electron beam evaporation according to claim 5, characterized in that: The surface roughness of the evaporation plane is less than 1.6 microns.

7. A chromium evaporation device for preparing a chromium film by electron beam evaporation according to claim 6, characterized in that: The crucible is made of oxygen-free copper / molybdenum material.

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