METHOD AND STAGE FOR VACUUM DEPOSITION OF METAL

Abstract

To provide an evaporator (stage) for vapor deposition of a metal film which makes wettability of molten metal even, and to provide a method for manufacturing the stage and a vapor deposition system including the stage.SOLUTION: A stage 1 installed in a chamber includes: a peripheral wall part 4; and an installation surface 3 positioned inside the peripheral wall part and installing an object thereto. The installation surface 3 is a stage including a projection shape of which a central part becomes higher than a part coming into contact with a pair of walls constituting the peripheral wall part 4 by 0.01 mm or more and 5 mm or less. A vapor deposition system includes the stage. A method for manufacturing a stage includes a step of polishing a substrate for a stage using a grindstone having a recessed tip.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for depositing metals and an evaporator (stage) for depositing metal films. [Background technology]

[0002] JP 2011-510178 A describes an evaporator (stage) for metal film deposition. The evaporator is used, for example, as a metal evaporation stage in a roll-to-roll (R2R) evaporation device. When depositing a metal film, a metal wire is generally continuously supplied to the roll-to-roll (R2R) evaporator. When the evaporator reaches a high temperature, the metal wire melts and is deposited on the target substrate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2011-510178 Summary of the Invention [Problem to be solved by the invention]

[0004] To ensure a uniform deposition film thickness, it is desirable for the molten metal to wet the mounting surface of the stage with a uniform thickness. If this can be achieved, splashes and other problems can be prevented, and a deposition film of uniform thickness can be formed on the target object.

[0005] One invention described in this specification aims to provide an evaporator (stage) for depositing metal or oxide films, which allows the molten metal to spread sufficiently within the stage and form a deposited film of uniform thickness on the target object. [Means for solving the problem]

[0006] To help the molten metal spread within the stage, a slope is provided in the width direction of the stage surface, allowing the molten metal to spread sufficiently within the stage, providing an evaporator (stage) for metal film deposition that can form a deposited film of uniform thickness on the target object.

[0007] The first invention of this specification relates to an evaporator (stage) that is installed in a chamber to deposit a metal film or an oxide film. The stage is, It has a peripheral wall portion 4 and a mounting surface 3 located inside the peripheral wall portion and on which an object is mounted, The mounting surface 3 has a convex shape in which the central portion is higher than the portion in contact with the pair of walls that make up the peripheral wall portion 4 .

[0008] The central part of the mounting surface 3 is preferably higher than the part of the mounting surface 3 that is in contact with the peripheral wall part 4 by 0.01 mm to 5 mm.

[0009] The longitudinal length of stage 1 is L S The longitudinal length of the mounting surface 3 is L C When L C / L S It is preferable that the value is 0.6 or more and 0.82 or less.

[0010] The portion of the mounting surface 3 that the metal wire contacts is designated as a first contact portion 5, The width of one end of stage 1 is W R The width of the other end is W L The distance from one end of the stage 1 to the first contact point 5 is L F When L F / L S is 0.1 or more and 0.4 or less, and W R / W L It is preferable that the value is 0.2 or more and 0.6 or less.

[0011] The portion of the mounting surface 3 that the metal wire contacts is designated as a first contact portion 5, The width of one end of stage 1 is W RThe width of the other end is W L The distance from one end of the stage 1 to the first contact point 5 is L F When L F / L S is 0.4 or more and 0.6 or less, and W R / W L It is preferable that the value is 0.8 or more and 1.2 or less.

[0012] This specification also discloses a deposition system including any of the stages described above.

[0013] The specification also discloses a method for manufacturing a stage, which includes a step of grinding a stage substrate using a grindstone with a recessed tip. [Effects of the Invention]

[0014] To help the molten metal spread within the stage, a slope is provided across the width of the stage surface, which allows the molten metal to spread sufficiently within the stage, providing an evaporator (stage) that can form a vapor deposition film of uniform thickness on the target object. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a conceptual diagram for explaining the stages of the present invention. [Figure 2] FIG. 2 is a conceptual diagram showing another example of a stage different from that shown in FIG. [Figure 3] FIG. 3 is a conceptual diagram for explaining a stage having a roughened portion on the rear surface. [Figure 4] FIG. 4 is a conceptual diagram for explaining a stage having a heat dissipation material layer on the rear surface. [Figure 5] FIG. 5 is a conceptual diagram for explaining the molten metal evaporation system. [Figure 6] FIG. 6 is a conceptual diagram for explaining the grindstone used to manufacture the stage. [Figure 7] FIG. 7 is a conceptual diagram for explaining a grindstone for manufacturing a stage. [Figure 8] Figure 8 is a photograph, in lieu of a drawing, of the grinding wheel used in manufacturing the stage. [Figure 9] Figure 9 is a photograph of the resulting stage, instead of a drawing. [Figure 10] FIG. 10 is a photograph, in lieu of a drawing, showing that the mounting surface of the obtained stage had a convex shape. [Figure 11] FIG. 11 is a photograph in place of a drawing showing the results of wettability evaluation of molten metal using the stages obtained in Comparative Example 1, Example 1, and Comparative Example 2. DETAILED DESCRIPTION OF THE INVENTION

[0016] The following describes embodiments of the present invention with reference to the drawings. The present invention is not limited to the embodiments described below, and also includes appropriate modifications of the embodiments below within the scope obvious to those skilled in the art.

[0017] FIG. 1 is a conceptual diagram illustrating the stage of the present invention. Stage 1 is installed in a deposition chamber and is used to evaporate molten metal. The deposition chamber is usually used to deposit a thin metal film or oxide film on the surface of an object with the interior held in a vacuum. When depositing an oxide film, a wire metal material can be reactively reacted in the vacuum chamber. A mounting surface 3 for accommodating molten metal is provided on the (upper) surface of stage 1. Mounting surface 3 refers to a portion (recess) that is lower than the surrounding area. Since mounting surface 3 is provided on the surface of stage 1, a surrounding wall 4 is formed around mounting surface 3.

[0018] FIG. 1(a) is a front view of a stage of the present invention. FIG. 1(b) is a conceptual diagram showing an example of an AA cross section in FIG. 1(a). FIG. 1(c) is a conceptual diagram different from FIG. 1(b) showing an example of an AA cross section in FIG. 1(a). The AA cross section is a cross section of the stage 1 in the minor axis direction (width direction). As shown in FIG. 1(b), the mounting surface 3 has a convex shape in which the central portion is higher than the portion in contact with a pair of walls constituting the peripheral wall portion 4. The example in FIG. 1(b) shows an example in which the convex shape has a gently curved surface. In this example, when the height between the portion in contact with a pair of walls constituting the peripheral wall portion 4 and the central portion is CH (Cavity Height), CH is 0.01 mm to 5 mm, and may be 0.01 mm to 1 mm, 0.01 mm to 0.5 mm, 0.02 mm to 0.1 mm, or 0.05 mm to 0.1 mm. The value of CH can be adjusted appropriately to match WH, where WH is the depth of the mounting surface (the height of the portion in contact with the pair of walls that make up the peripheral wall portion 4). CH is preferably between 0.01WH and WH, and may be between 0.05WH and 0.5WH, or may be between 0.05WH and 0.2WH. In the example shown in FIG. 1(a), the peripheral wall portion 4 rises vertically. However, the peripheral wall portion 4 may also be inclined. As shown in FIG. 1(c), the convex shape may be a mountain shape. In this case, the mounting surface 3 has a relatively flat inclined surface from the center to the bottom. This convex shape allows the molten metal to move and spread smoothly within the mounting plane.

[0019] The cross section BB in FIG. 1(a) may be flat, or may have a convex shape as shown in FIG. 1(b) or FIG. 1(c).

[0020] The width (at the center region) of the mounting surface 3 is W C Then, W C Examples of the depth of the mounting surface 3 are 15 mm to 60 mm, 20 mm to 40 mm, or 25 mm to 36 mm. Examples of the depth of the mounting surface 3 are 0.5 mm to 4 mm, 0.5 mm to 3 mm, or 1 mm to 2 mm.

[0021] The longitudinal length of stage 1 is L S The longitudinal length of the mounting surface 3 is L C When L C / L S It is preferable that the value of is between 0.6 and 0.82. There are usually electrodes on both ends of the stage, and these parts are cooled. As a result, the temperature near the electrodes drops. By taking into account the phenomenon of this temperature drop near the electrodes and the temperature drop in the parts in contact with the metal wire or molten metal, and controlling the size and position of the mounting surface, it becomes possible to maintain a uniform temperature of the molten metal. In this example, the length of the cavity (mounting surface) is shorter than in conventional stages, so the effect of low-temperature electrode parts can be reduced. This L C / L S The smaller the value of L, the wider the stage, and the more effectively the temperature drop near the electrodes can be suppressed. On the other hand, if this value is small, the surface area of ​​the mounting surface 3 becomes small, and it becomes necessary to make the stage larger. From this perspective, L C / L S The value of may be 0.6 or more and 0.8 or less, or 0.6 or more and 0.7.5 or less, or 0.6 or more and 0.7 or less, or 0.65 or more and 0.8 or less, or 0.7 or more and 0.8 or less, or 0.75 or more and 0.8 or less, or 0.65 or more and 0.75 or less.

[0022] L S Examples are 65mm or more and 260mm or less, 100mm or more and 160mm or less, 110mm or more and 150mm or less, or 120mm or more and 140mm or less.

[0023] A preferable example of this stage 1 is a stage having a width at one end (a width in the longitudinal direction of the stage 1) of W R The width of the other end (the width in the longitudinal direction of stage 1) is W L The distance from one end of the stage 1 to the first contact point 5 is L F When L F / L S is 0.1 or more and 0.4 or less, and W R / W L The value of W is between 0.2 and 0.6. R and W L W can also be considered as the distance between the edge of stage 1 and the mounting surface. R / W L The value of is 0.2 or more and 0.6 or less, and may be 0.2 or more and 0.55 or less, or 0.2 or more and 0.5 or less, or 0.2 or more and 0.4 or less, or 0.3 or more and 0.6 or less, or 0.4 or more and 0.6 or less, or 0.5 or more and 0.6 or less, or 0.3 or more and 0.5 or less, or 0.35 or more and 0.45 or less. L F / L S The value of is 0.1 or more and 0.4 or less, and may be 0.1 or more and 0.35 or less, or 0.1 or more and 0.3 or less, or 0.1 or more and 0.25 or less, or 0.2 or more and 0.4 or less, or 0.25 or more and 0.4 or less, or 0.3 or more and 0.4 or less, or 0.25 or more and 0.35 or less, or 0.3 or more and 0.35 or less. The first contact portion 5 is the portion of the mounting surface 3 that the metal wire comes into contact with. This first contact portion 5 is usually the same location. Alternatively, the temperatures of the mounting surface 3 and the molten metal may be calculated, and the contact portion may be moved to the second contact portion based on the calculated temperature. The first contact portion 5 is the portion that the metal wire first comes into contact with when there is no molten metal on the mounting surface 3. The metal of the metal wire may be any metal that is desired to be deposited on the surface of the object. Examples of such metals are aluminum, gold, platinum, silver, and copper. The metal wire is usually linear and is supplied from outside the stage 1. When it comes into contact with the mounting surface 3 (or the molten metal) at the first contact portion 5, the contacted portion melts and becomes molten metal. This example is W. R and W L The above is a different aspect.

[0024] Figure 2 is a conceptual diagram showing another example of the stage from Figure 1. In this example, the thickness of the left and right walls (W R ,W L ) is not a big gap. F / L Sis 0.4 or more and 0.6 or less, and W R / W L The value of is between 0.8 and 1.2. F / L S is 0.4 or more and 0.6 or less, may be 0.4 or more and 0.6 or less, may be 0.4 or more and 0.55 or less, may be 0.4 or more and 0.5 or less, may be 0.45 or more and 0.6 or less, may be 0.5 or more and 0.6 or less, may be 0.45 or more and 0.55 or less, may be 0.45 or more and 0.5 or less, may be 0.5 or more and 0.55 or less. In this example, W R / W L The value of is 0.8 or more and 1.2 or less, may be 0.8 or more and 1.1 or less, may be 0.8 or more and 1 or less, may be 0.8 or more and 0.9 or less, may be 0.9 or more and 1.2 or less, may be 1 or more and 1.2 or less, may be 1.1 or more and 1.2 or less, may be 0.95 or more and 1.15 or less, may be 0.9 or more and 1.1 or less.

[0025] The evaporator (stage) is supported on the left and right by, for example, two electrodes 6a and 6b (see Figure 5). The two electrodes are usually cooled by a liquid. For this reason, heat loss occurs through the electrodes, causing the temperature at the end of the evaporator to drop. The electrodes 6a and 6b consume 6 to 8 kW / h of power, which causes them to become very hot.

[0026] FIG. 3 is a conceptual diagram illustrating a stage having a roughened portion on its back surface. In the example shown in FIG. 3, a roughened portion 13 is provided in a central region 11 of the back surface of the stage. The central region is an area including the center of gravity of the back surface, and occupies an area of ​​10% to 80% (20% to 70%, 30% to 60%, 40% to 50%, or 20% to 50%) of the entire back surface. The roughened portion is provided to increase the surface area and thereby enhance heat dissipation. The roughened portion refers to a portion whose surface is rougher than the surrounding area. The roughened portion may be roughened by, for example, sandblasting with the areas other than the roughened portion masked, or by chemical etching. For example, the roughening process may be performed while the areas not to be roughened are masked. The roughened portion 13 may have a surface roughness Rz value of 8 to 14 (preferably 9 to 13, or 9.5 to 12.5, or 10 to 12) and an Ra value of 0.65 to 1.5 (preferably 0.7 to 1.4, or 0.8 to 1.3). These values ​​may be determined in accordance with JIS B 0601-2001.

[0027] Fig. 4 is a conceptual diagram illustrating a stage having a heat dissipation material layer on its back surface. In the example shown in Fig. 4, a heat dissipation material layer 15 is provided in a central region 11 on the back surface of the stage. The heat dissipation material layer 15 preferably has an emissivity of 0.01 or more and 0.4 or less. Heat dissipators having a predetermined emissivity are well known, as described in, for example, Japanese Patent No. 6266162 and Japanese Patent No. 6196078. A heat dissipation material layer refers to a layer having a higher emissivity than other parts of the stage.

[0028] Next, the molten metal evaporation system will be explained. FIG. 5 is a conceptual diagram for explaining a molten metal evaporation system. As shown in FIG. 5, this molten metal evaporation system 19 has multiple stages 1. Each of the multiple stages has a shape with a short axis 21 in the central region 7, and the multiple stages are installed adjacent to each other so that their respective long axes 23 are parallel. In other words, in the example shown in FIG. 5, the multiple stages are arranged in a horizontal row. The spacing W between the multiple stages is S is the width (of the central region) of the mounting surface 3, W C Then, W C / 10 or more W C / 4 or less, and W C / 8 or moreW C / 6 or less, W C / 10 or more W C / 5 or less, W C / 5 or more W C 5 has a polygonal mounting surface. The shape of the mounting surface is not limited to a square, but may be a polygon or an ellipse.

[0029] Next, we will explain how to use the molten metal evaporation system. Stage 1 is part of the molten metal evaporation system. The molten metal evaporation system can be used to deposit metal onto an object. For example, an object and a stage are placed in a vacuum chamber (evaporation chamber). A metal wire is then supplied to a predetermined position on the stage. A vacuum is then drawn inside the evaporation chamber. Electricity is applied to the electrodes at both ends of the stage to heat it. After the temperature of the stage reaches a certain value, the metal wire is brought into contact with a first contact portion 5 on the mounting surface 3 on the surface of the stage 1 placed in the evaporation chamber. This process can be achieved by using a metal wire supply device to push the metal wire toward the mounting surface. The metal wire that comes into contact with the mounting surface then melts and becomes molten metal. The metal wire is then supplied to the mounting surface. The metal wire then comes into contact with the molten metal and the mounting surface and melts. The amount of molten metal then gradually increases. The increased amount of molten metal gradually evaporates and is deposited on the surface of the object. Meanwhile, the increased amount of molten metal moves within the mounting surface 3. The molten metal moves from low-temperature areas to high-temperature areas within the mounting surface 3. Low-temperature areas are parts of the mounting surface whose temperature has dropped due to contact with the metal wire or molten metal. In this invention, even if the temperature of the mounting surface drops due to the cooling mechanism on the electrode side, if the molten metal spreads, the supply location of the stage and metal wire is controlled so that the molten metal moves in the direction of higher temperatures. It is preferable that the movement of the molten metal from low-temperature areas to high-temperature areas on the mounting surface continue for the period during which the molten metal has spread over the entire mounting surface.

[0030] Figure 6 is a conceptual diagram illustrating the deposition device. The deposition device feeds a wire to the center of a rectangular mounting surface, for example. An example of the feed rate is 1500 mm / min, and when using aluminum wire, the rate is approximately 10 g / min per evaporator.

[0031] Next, we will explain the manufacturing method of the stage. The method includes the step of grinding a stage substrate with a grindstone having a recessed tip.

[0032] FIG. 7 is a conceptual diagram illustrating a grindstone for manufacturing a stage. This specification also discloses a grindstone for manufacturing a stage. This grindstone may be made of a known grindstone material. However, this grindstone 31, unlike grindstones for manufacturing flat stages, has a recessed tip, forming a recessed portion 33. As conceptually illustrated in FIG. 7, a stage having a mounting surface shaped as shown in FIG. 1 can be obtained by vibrating this grindstone from side to side while contacting the tip (recessed portion 33) with a substrate. The left-right vibration speed can be adjusted as appropriate. The width BW of the recessed portion 33 of this grindstone can be adjusted as appropriate to match the size of the stage to be manufactured, and is, for example, 1 mm to 10 cm, preferably 5 mm to 3 cm, or may be 5 mm to 15 mm. The height BH of the recessed portion 33 can be adjusted as appropriate depending on the width BW, and is, for example, 1 mm to 5 cm, or may be 2 mm to 3 cm, or may be 5 mm to 10 mm. [Example]

[0033] The present invention will be specifically described below using examples. The present invention is not limited to the above-described embodiments and the following examples, and includes those that appropriately incorporate known elements.

[0034] [Example 1] A stage of the type shown in Figure 1 was fabricated. Figure 8 is a photograph, instead of a drawing, of the grinding wheel used to manufacture the stage. Figure 9 is a photograph, instead of a drawing, of the resulting stage. Figure 10 is a photograph, instead of a drawing, showing that the mounting surface of the resulting stage had a convex shape. The size of the stage was a square pillar approximately 130 mm x 35 mm x 10 mm. The mounting surface was 94 mm x 31 mm x 1 mm. The WR and WL were 10 mm and 26 mm, respectively. For a mounting surface depth of 1 mm, the CH was 0.8 mm to 0.9 mm.

[0035] [Comparative Example 1] The stage was created in the same manner as in Example 1, except that the size of the stage was a square prism of approximately 130 mm x 35 mm x 10 mm, with a rectangular, flat mounting surface of 120 mm x 31 mm x 1 mm on the surface.

[0036] Comparative Example 2 The stage was created in the same manner as in Example 1, except that the size of the stage was a square prism of approximately 130 mm x 35 mm x 10 mm, with a mounting surface of 120 mm x 31 mm x 1 mm that was rectangular and concave (lower in the center) on the surface.

[0037] Fig. 11 is a photograph in place of a drawing showing the results of evaluating the wettability of molten metal using the stages obtained in Comparative Example 1, Example 1, and Comparative Example 2. As shown in Fig. 11, the stage of Example 1 had good wettability.

[0038] [Example 2] A stage of the type shown in Figure 2 was fabricated. The size of the stage was a square pillar of approximately 130 mm x 35 mm x 10 mm. The mounting surface was 94 mm x 31 mm x 1 mm. The WR and WL were both 18 mm. The CH was 0.8 mm to 0.9 mm for a mounting surface depth of 1 mm.

[0039] A computer simulation was used to evaluate the wettability of the molten metal when using the stages of Examples 1 and 2. An example of the feed rate was 1500 mm / min, and when using an aluminum wire, the rate was approximately 10 g / min per evaporator. Furthermore, a computer simulation was used to determine the temperature changes of the molten metal and various parts of the mounting surface. The results showed that using the stage of the present invention made the wettability of the molten metal uniform, allowing the molten metal to spread throughout the entire stage. Furthermore, it was found that the molten metal constantly moved from low-temperature areas (areas on the mounting surface where the molten metal was present) to high-temperature areas (areas on the mounting surface where the molten metal moved) while filling the mounting surface. Therefore, it is believed that using the stage of the present invention would make the temperature of the molten metal uniform, allowing a uniform deposition film to be formed on the target object. [Industrial Applicability]

[0040] The present invention can be used in the technical field of depositing thin metal films and oxide films. [Explanation of symbols]

[0041] 1st Stage 3 Mounting surface 4 Peripheral wall (wall) 5. First contact point 7 Metal Wire 11 Central area of ​​the back 13 Roughened area 15 Heat dissipation material layer 21 Short axis 23 Long axis

Claims

1. A method for manufacturing a stage (1) to be installed in a chamber, comprising a step of grinding a stage substrate using a grindstone with a recessed tip, The stage comprises: The apparatus has a peripheral wall (4) and a mounting surface (3) located inside the peripheral wall and on which molten metal is mounted; The mounting surface (3) has a convex shape in which the central portion is higher than the portion in contact with the pair of walls constituting the peripheral wall portion (4). method.

2. 2. The method of claim 1 , The central portion of the mounting surface (3) is higher by 0.01 mm to 5 mm than the portion of the mounting surface (3) that is in contact with the peripheral wall portion (4). method.

3. 2. The method of claim 1 , The length of the stage (1) in the longitudinal direction is L Ｓ The longitudinal length of the mounting surface (3) is L Ｃ When this is done, L Ｃ / L Ｓ The value of is 0.6 or more and 0.82 or less.

4. 4. The method of claim 3, A portion of the mounting surface (3) that comes into contact with the metal wire is designated as a first contact portion (5), The width of one end of the stage (1) is W Ｒ The width of the other end is W Ｌ The distance from the one end of the stage (1) to the first contact portion (5) is L Ｆ When we do this, L Ｆ / L Ｓ is 0.1 or more and 0.4, and W Ｒ / W Ｌ The value of is 0.2 or more and 0.6 or less.

5. 4. The method of claim 3, A portion of the mounting surface (3) that comes into contact with the metal wire is designated as a first contact portion (5), The width of one end of the stage (1) is W Ｒ The width of the other end is W Ｌ The distance from the one end of the stage (1) to the first contact portion (5) is L Ｆ When we do this, L Ｆ / L Ｓ is 0.4 or more and 0.6 or less, and W Ｒ / W Ｌ The value of is 0.8 or more and 1.2 or less.

6. A method for manufacturing a deposition system including the stage, comprising the step of manufacturing the stage by the method according to any one of claims 1 to 5.

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