Vacuum deposition apparatus

Abstract

The vacuum deposition apparatus EM comprises a ceramic deposition boat 3 installed in a vacuum chamber 1, a power supply Ps for energizing and heating the deposition boat, and a material supply means 6 for supplying wire-shaped deposition material. The apparatus is configured to enable stable film formation at a high deposition rate even when the supply speed of the deposition material Em is increased. [Solution] The position on the bottom surface of the cavity 31a of the deposition boat where the leading edge Em1 of the deposition material makes contact is defined as the impact position, and a locking groove 71 is provided recessed in the bottom surface of the cavity one direction forward from the impact position to lock the leading edge which slides forward in one direction. The material supply amount per unit volume is πr 2 ×650mm 3 When set to more than / min and the power supply Ps is operated at 90% or more of the rated power capacity, the groove width W2 of the locking groove and the groove depth D1 from the bottom of the cavity are set so that the effective length of liquid-phase heating is 3 or more.

Description

[Technical Field]

[0001] The present invention relates to a vacuum deposition apparatus comprising a deposition boat made by sintering raw materials mainly composed of boron nitride and titanium boride, which is installed in a vacuum chamber; a power supply for energizing the deposition boat; and a material supply means for supplying a wire-shaped deposition material mainly composed of Cu and having a radius r in the range of 0.5 to 2 mm. The apparatus continuously supplies the wire-shaped deposition material from one direction to the cavity of the deposition boat, which is heated by the energization, and deposits a predetermined thin film onto an object to be deposited in a vacuum chamber by dissolving and evaporating the deposition material in the cavity. [Background technology]

[0002] An example of the above type of vacuum deposition apparatus is the one described in Patent Document 1. In this apparatus, for example, when depositing a copper film onto the surface of a substrate as the object to be deposited, the deposition boat is made of ceramics sintered from a material mainly composed of boron nitride and titanium boride, which imparts conductivity to the deposition boat. As the wire-shaped deposition material, copper of a purity corresponding to the quality of the copper film is formed to a predetermined outer diameter. Then, an electric current is passed through the deposition boat in a vacuum chamber with a vacuum atmosphere to resistively heat it to a predetermined temperature (for example, 1400°C to 1700°C), and the wire-shaped deposition material is continuously supplied to the cavity (recess) of the deposition boat from one direction at a predetermined supply rate. As a result, molten Cu is formed in the cavity as the deposition material melts and spreads, and the molten material that evaporates from the surface of the molten metal adheres to and deposits on the substrate surface, thereby depositing a Cu film. When selecting a power supply to provide current to the deposition boat, one with a predetermined rated current capacity is chosen considering factors such as the heating temperature range of the deposition boat and the manufacturing cost of the equipment. However, the higher the rated current capacity is compared to the desired deposition rate, the less cost-effective the equipment becomes.

[0003] Equipment that contributes to industrial development must be cost-effective and highly efficient. In other words, the supply speed of wire-shaped deposition material is also an important factor in improving the deposition rate, specifically in improving productivity. For example, if the deposition material is made of copper, has an outer diameter of 1.5 mm (r=0.75), and the power supplied to the deposition boat is 9 kW to 14 kW, then when the supply speed is relatively slow (for example, 500 mm / min), sufficient heat is applied to the tip of the deposition material from the molten metal already wetted and spread on the surface of the heated deposition boat and within the cavity (i.e., heat is transferred from the deposition boat to the tip of the deposition material by radiation as the dominant factor, and it is heated above its melting point). As a result, the deposition material melts sequentially from its tip before it penetrates the molten metal and contacts the bottom of the cavity. Then, when the amount of dissolved deposition material and the amount of evaporation from the surface of the molten metal reach equilibrium, the amount of molten metal wetting and spreading within the cavity stabilizes, allowing for film formation at a predetermined deposition rate.

[0004] If the supply rate is relatively fast (for example, 600 mm / min), the leading edge of the deposition material cannot be completely dissolved before it penetrates the molten metal. However, when this undissolved leading edge of the deposition material penetrates the molten metal and contacts the bottom of the cavity (hereinafter, the position on the bottom of the cavity where the leading edge of the deposition material contacts is referred to as the "impact point"), it receives heat from the deposition boat (conduction is the dominant factor) and melts sequentially from the leading edge. Then, similarly to the above, the amount of dissolved deposition material and the amount of evaporation from the surface of the molten metal reach equilibrium, stabilizing the amount of molten metal and surface area wetting the cavity, and enabling film formation at a higher deposition rate. However, if the supply rate is even faster than the above speed (for example, 650 mm / min), even under conditions where the amount of heat generated by the deposition boat is considered to be near its maximum (for example, 90% or more of the rated power capacity of the power supply), the deposition material at the impact point cannot melt in time.

[0005] If the deposition material cannot melt quickly enough at the point of impact, the material will slide forward in one direction along the bottom of the cavity due to the forward force acting on it during the feeding motion. This phenomenon is more pronounced when the deposition boat is made of the aforementioned ceramics and copper, which has a relatively high melting point, is used as the deposition material. When such a sliding phenomenon occurs, the effective supply of deposition material to the cavity decreases, leading to a decrease in the deposition rate, and in some cases, smooth material supply for deposition may become impossible. Furthermore, if the deposition material cannot melt quickly enough at the point of impact, the leading edge of the deposition material may deform (in a bow shape), reducing the surface pressure, which may increase the contact thermal resistance and make the deposition material even more difficult to melt. In such cases, using a power supply with a larger rated power capacity would be an option, but this would significantly increase the manufacturing and running costs of the equipment. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 7530533 [Overview of the project] [Problems that the invention aims to solve]

[0007] In view of the above, the present invention aims to provide a low-cost vacuum processing apparatus that can stably deposit films at a high deposition rate, even when using a power supply with a limited rated power capacity and increasing the supply speed of the deposition material, by adopting a configuration that improves the thermal conductivity from the deposition boat to the wire-shaped deposition material compared to conventional systems. [Means for solving the problem]

[0008] To solve the above problems, the present invention provides a vacuum deposition apparatus comprising a deposition boat made by sintering raw materials mainly composed of boron nitride and titanium boride, installed in a vacuum chamber, a power supply for energizing the deposition boat, and a material supply means for supplying wire-shaped deposition material mainly composed of Cu and having a radius r in the range of 0.5 to 2 mm, wherein the wire-shaped deposition material is continuously supplied from one direction to the cavity of the deposition boat heated by energization, and a predetermined thin film is deposited on the object to be deposited in the vacuum chamber by dissolving and evaporating the deposition material in the cavity, the position on the bottom surface of the cavity to which the tip of the deposition material abuts when supplied by the material supply means is defined as the impact position, and a locking groove is recessed in the bottom surface of the cavity one direction forward from the impact position to lock the tip of the deposition material that slides one direction forward, and the amount of material supplied per unit volume by the material supply means is πr 2 ×650mm 3 The locking groove width and groove depth from the cavity bottom surface are set such that the effective length of liquid-phase heating is 3 or more when the setting is greater than or equal to / min and the power supply is operated at 90% or more of its rated power capacity.

[0009] According to the present invention, the amount of material supplied per unit volume is πr 2 ×650mm 3Even if a sliding phenomenon occurs from the point of impact due to the setting being greater than / min, the leading edge of the deposition material sliding along the bottom surface of the cavity falls into a locking groove located one direction forward of the point of impact and is locked in the locking groove (specifically, the wall surface on the one-direction forward side that defines the locking groove). In other words, further sliding in one direction forward within the cavity is suppressed. At this time, there is molten deposition material with a locally increased volume in the locking groove. Here, through diligent research by the inventors of this application, they focused on the state in which the leading edge of the deposition material falls into the locking groove and is locked in the locking groove due to a sliding phenomenon from the point of impact. At this time, based on the length over which the dissolution of the leading edge of the deposition material is promoted by the molten metal present in the locking groove (hereinafter referred to as the "effective liquid-phase heating length"), they found that if the groove width of the locking groove and the groove depth from the cavity bottom surface are set so that this effective liquid-phase heating length is 3 or more, the thermal conductivity is improved and the dissolution of the deposition material is promoted (i.e., the deposition material is reliably dissolved), even when operating at 90% or more of the rated power capacity, and further sliding is suppressed as much as possible. As a result, even at high deposition rates that were not possible with conventional configurations, stable film formation is possible, and moreover, costs can be reduced by using a power supply with a limited rated power capacity. Note that the locking groove may be formed so that the point of impact is included within its bottom surface. This ensures that when a slip phenomenon occurs from the point of impact, the leading edge of the deposited material is locked as quickly as possible against the wall on the unidirectional front side that defines the locking groove (in other words, the amount of slip in the unidirectional forward direction of the deposited material is minimized), thereby reliably preventing problems such as a decrease in the effective supply of deposited material to the cavity.

[0010] In this invention, a configuration can be adopted in which multiple locking grooves are provided at intervals in one direction. Even if the material slips again after overcoming the front wall of one locking groove, the leading edge of the deposition material will be locked in the locking groove located further forward, which is advantageous. When locking grooves are recessed in the bottom surface of the cavity, the volume of molten metal when the deposition material is dissolved in the cavity increases by the volume of the locking grooves. At this time, the current flowing through the deposition boat is diverted to molten metal such as copper, which has good thermal conductivity, so depending on the rated current capacity of the power supply, the deposition boat may not be able to be heated to a predetermined temperature. For this reason, when multiple locking grooves are provided, for example, the groove length, groove width, and groove depth of each engagement groove should be set considering the total volume (if two locking grooves are provided, the volume of each locking groove should be set to half the volume when one locking groove is provided). Furthermore, the accuracy of the impact when the leading edge of the vapor-deposited material contacts the impact point due to the feeding operation of the material supply means varies depending on the wire diameter and residual strain of the wire-like vapor-deposited material. Considering this impact accuracy (in other words, the range of variation in the impact position of the vapor-deposited material starting from the impact point), there are no particular restrictions on the contour of the locking groove as long as it can reliably lock the leading edge of the slipped vapor-deposited material. For example, it can have a rectangular, circular, or arched contour in plan view. [Brief explanation of the drawing]

[0011] [Figure 1] A schematic cross-sectional view illustrating the configuration of the vacuum deposition apparatus of this embodiment. [Figure 2] An enlarged view illustrating the sliding of the deposition material on the surface of the deposition boat in a conventional vacuum deposition apparatus. [Figure 3] (a) is a partially enlarged plan view of the vapor deposition source shown in Figure 1, and (b) is a partially enlarged cross-sectional view thereof. [Figure 4] An enlarged view illustrating the locking state at the locking groove of the leading edge of the vapor-deposited material. [Figure 5] (a) is an enlarged plan view of the vapor deposition source relating to the modified example, and (b) is an enlarged cross-sectional view thereof. [Figure 6] (a) and (b) are enlarged cross-sectional views of a vapor deposition source relating to other modifications.

Embodiment for Carrying out the Invention

[0012] Hereinafter, with reference to the drawings, an embodiment of the vacuum evaporation apparatus EM of the present invention will be described by taking as an example the case where a deposition target is a rectangular glass substrate (hereinafter referred to as "substrate Sg"), and a wire-shaped evaporation material Em mainly composed of Cu (copper) and having a range of Φ1 mm to 4 mm (radius r is 0.5 to 2 mm) is continuously supplied and evaporated in a vacuum chamber 1 in a vacuum atmosphere to deposit a Cu film on the film-forming surface of the substrate Sg. Hereinafter, the two horizontal axial directions perpendicular to each other are defined as the X-axis direction and the Y-axis direction, and terms indicating directions such as up and down are based on FIG. 1 showing the installation posture of the vacuum evaporation apparatus EM.

[0013] Referring to FIG. 1, the vacuum evaporation apparatus EM of the present embodiment is a so-called in-line type and includes a vacuum chamber 1. A vacuum pump is connected to the vacuum chamber 1 via an exhaust pipe (not shown), and the inside thereof can be evacuated to a predetermined pressure (vacuum degree) to form a vacuum atmosphere (for example, during evaporation, the inside of the vacuum chamber 1 can be maintained in a pressure range of 1×10 -2 Pa to 5×10 -4 Pa). A substrate transfer device 2 is provided in the upper space of the vacuum chamber 1. The substrate transfer device 2 has a carrier 21 that holds the substrate Sg with the lower surface as the film-forming surface open, and the carrier 21, and thus the substrate Sg, can be transferred at a predetermined speed in the Y-axis direction in the vacuum chamber 1 by a drive device (not shown). Since a known substrate transfer device 2 can be used, further description thereof will be omitted. And an evaporation source Es having an evaporation boat is provided in the lower space of the vacuum chamber 1 opposite to the substrate Sg transferred in the Y-axis direction.

[0014] The deposition source Es is longitudinal in the X-axis direction and includes a ceramic deposition boat 3. The deposition boat 3 has a boat body 31 in which a cavity 31a, which is a recess with a flat inner bottom surface, is formed, and electrode mounting plate portions 31b are formed in the portions of the boat body 31 that extend on both sides of the cavity 31a in the X-axis direction. The deposition boat 3 is made of a material sintered from a raw material containing boron nitride (BN) and titanium boride (TiB2) to impart conductivity, in a predetermined weight ratio. In this case, metal compounds such as aluminum nitride or tungsten carbide can be added to impart wettability. As known sintering methods can be used, further explanation is omitted. Two support bases 4, 4 made of insulating material are installed on the inner surface of the lower wall 1a of the vacuum chamber, spaced apart in the X-axis direction.

[0015] A pair of left and right electrode clamps 5, 5, made of a highly conductive metal such as copper, are installed on the upper surfaces of the support bases 4, 4. The deposition boat 3 is detachably held by horizontally moving at least one of the electrode clamps 5 in the X-axis direction and pressing the electrode mounting plates 31b of the boat body 31 against both sides in the longitudinal direction. When the deposition boat 3 is held, it is positioned at a predetermined height from the inner surface of the lower wall 1a of the vacuum chamber, with the bottom surface of the cavity 31a being approximately horizontal. The output from a power supply Ps installed outside the vacuum chamber 1 is connected to each electrode clamp 5, 5, allowing current to flow between the two electrode mounting plates 31b, 31b via the electrode clamps 5, 5. A known power supply Ps can be used, and one that can output a predetermined rated current capacity (e.g., 60A) is selected considering the material of the deposition boat 3 according to the deposition material Em, its heating temperature range, and the manufacturing cost of the equipment.

[0016] Inside the vacuum chamber 1, there is provided a material supply means 6 for continuously supplying a wire-shaped deposition material Em to the cavity 31a from the X-axis direction which is in one direction. The material supply means 6 has a housing 61 installed on the side facing away from the evaporation source Es of the anti-deposition plate 11 disposed inside the vacuum chamber 1. Inside the housing 61, there are stored a pay-out roller 62, a motor 63 for rotationally driving the pay-out roller 62, and a pair of upper and lower guide rollers 64, 64. A protruding pipe portion 61a is formed on the side wall of the housing 61 located on the evaporation source Es side, and the housing 61 is installed inside the vacuum chamber 1 such that the protruding pipe portion 61a passes through the through-hole 11a formed in the anti-deposition plate 11. At the tip of the protruding pipe portion 61a, a guide pipe 65 having a predetermined length with a tip portion curved downward is attached to guide the wire-shaped deposition material Em toward the cavity 31a.

[0017] The deposition material Em is pre-wound around the pay-out roller 62. Then, the tip Em1 of the wire-shaped deposition material Em wound around the pay-out roller 62 is pulled out, passed between the pair of upper and lower guide rollers 64, 64, and inserted through the space inside the protruding pipe portion 61a and then through the guide pipe 65. The wire-shaped deposition material Em is prepared such that the tip portion Em1 of the deposition material Em protruding from the guide pipe 65 abuts against the inner bottom surface of the cavity 31a from above at the central region in the longitudinal direction of the cavity 31a. At this time, the incident angle α1 of the deposition material Em with respect to the evaporation boat 3 (that is, the angle formed by the bottom surface of the cavity 31a and the wire-shaped deposition material Em) is set within a range of, for example, 40° to 45°. And the position on the bottom surface of the cavity 31a where the tip portion Em1 (more specifically, the lower portion of the tip portion Em1) of the deposition material Em abuts becomes the landing position Ip.

[0018] When depositing a Cu film on the film deposition surface (bottom surface) of a substrate Sg in a vacuum chamber 1 with a vacuum atmosphere using the vacuum deposition method, a power supply Ps installed outside the vacuum chamber 1 is used to pass current between the two electrode mounting plate sections 31b, 31b via electrode clamps 5, 5, thereby resistively heating the boat body 31 by Joule heating. The power supplied at this time is set according to the film deposition rate when depositing the Cu film on the bottom surface of the substrate Sg, and is set to a range of 9kW to 14kW so that the deposition boat 3 can be heated to a temperature range of 1400℃ to 1700℃. When the deposition boat 3 reaches a predetermined temperature, the motor 63 rotates the feed roller 62 to feed out the wire-shaped deposition material Em. Then, a molten Cu is formed in the cavity 31a as the deposition material Em melts and spreads, and the molten Cu that evaporates from the surface of the molten material adheres to and deposits on the film deposition surface of the substrate Sg, thereby depositing (forming) a Cu film.

[0019] Referring to Figure 2, when the supply rate (feed rate) of the deposition material Em to the cavity 31a is within a predetermined range (for example, 500 mm / min to 600 mm / min) during deposition, the deposition material Em can be dissolved sequentially from its leading edge Em1 side. Then, the amount of dissolved deposition material Em and the amount of evaporation from the molten metal surface M1 of the molten metal Mm reach equilibrium, stabilizing the amount of molten metal Mm wetting and spreading within the cavity 31a, and allowing film formation at a predetermined deposition rate. On the other hand, when the supply rate exceeds a certain speed (for example, 650 mm / min) (i.e., the amount of material supplied per unit volume by the material supply means 6 becomes πr 2 ×650mm 3Under conditions set to 1 / min or higher, the melting of the leading edge Em1 of the deposition material Em at the impact point Ip becomes insufficient. At this time, a force acts on the deposition material Em in the forward direction in the X-axis direction (right side in Figure 2) due to the feeding operation from the feed roller 62. As a result, as shown by the dashed line in Figure 2, a phenomenon occurs in which the material slides forward in one direction from the impact point Ip while sliding along the bottom surface of the cavity 31a. Such a sliding phenomenon from the impact point Ip can lead to a decrease in the deposition rate, for example. Furthermore, the inventors believe that if the melting of the deposition material Em at the impact point Ip becomes insufficient, the leading edge Em1 of the deposition material Em is assumed to deform (in a bow shape), reducing the surface pressure, and coupled with an increase in contact thermal resistance, the deposition material Em may become even more difficult to melt. Therefore, if a configuration can be adopted that improves the thermal conductivity from the deposition boat to the wire-shaped deposition material, it will not be necessary to change to a power supply Ps with a larger rated power capacity, which would increase costs in the vacuum deposition apparatus. Specifically, it is desirable to suppress slippage from the point of impact Ip (and in some cases, deformation of the tip Em1 at the point of impact Ip) even at a relatively high speed, while simultaneously increasing the thermal conductivity.

[0020] Referring also to FIGS. 3(a) and (b), in the present embodiment, a locking groove 71 for suppressing the forward sliding of the tip Em1 in the X-axis direction is recessed in the central portion in the X-axis direction of the bottom surface of the cavity 31a. At this time, the landing position Ip of the vapor deposition material Em is made to be included within the bottom surface 71a of the locking groove 71, and the locking groove 71 has a strip-shaped contour that is longitudinal in the X-axis direction. The length in the Y-axis direction (groove length W1) of the locking groove 71 is appropriately set in consideration of the landing accuracy when the tip Em1 of the vapor deposition material Em contacts the landing position Ip by the feeding operation from the feeding roller 62. On the other hand, the length in the X-axis direction (groove width W2 of the locking groove) and the groove depth D1 from the bottom surface of the cavity of the locking groove 71 are set so that the effective length of liquid-phase heating is 3 or more. Here, the "effective length of liquid-phase heating" means that, as shown in FIG. 4, due to the occurrence of a sliding phenomenon in the forward direction from the landing position Ip because the dissolution of the tip Em1 of the vapor deposition material Em in the cavity 31a cannot catch up, when the tip Em1 is locked by the locking groove 71 (more specifically, by the wall surface 71b on the forward side in one direction that defines this), heat transfer due to convection by the molten metal Mm present in the locking groove 71 is added, thereby improving heat conduction and promoting the dissolution of the tip Em1 of the vapor deposition material Em. In the present embodiment, the effective length of liquid-phase heating is defined by the product of the heating perimeter ratio and the length L1 of the vapor deposition material Em actually in contact with the molten metal in the locking groove 71. The heating perimeter ratio is the ratio of the partial perimeter of the vapor deposition material Em actually in contact with the molten metal Mm in the locking groove 71 to the total perimeter of the vapor deposition material Em in the cross section of the wire-shaped vapor deposition material Em, and is used as a cross-sectional shape coefficient representing the ease of temperature rise of the wire-shaped vapor deposition material. The length L1 is the diagonal length of the rectangle represented by the groove width W2 and the groove depth D1 of the locking groove, and in the present embodiment, L1 2 =W2 2 +D1 2The following is used. In reality, the heating circumference ratio is nonlinear in the X-axis direction because the total circumference of the deposited material Em decreases at a constant rate as the dissolution of the tip Em1 of the deposited material Em progresses. However, in this embodiment, this is ignored when determining the heating circumference ratio, and only the cross-section (diameter and radius) of the wire-shaped deposited material Em and the groove depth D1 are used. Specifically, if the groove depth D1 and the diameter of the deposited material Em are the same, the heating circumference ratio is 1; if it is the same as the radius r of the deposited material Em, the heating circumference ratio is 0.5; and if it is half the radius r of the deposited material Em, the heating circumference ratio is 1 / 3. However, since it is clear that the heating circumference ratio approaches 1 as it progresses in the X-axis direction, the accuracy of the physical model used may be improved by performing a correction using a correction coefficient table (for example, monotonically increasing correlated with the groove width W2) based on the simulation results.

[0021] Based on the above, the amount of material supplied per unit volume of the vapor deposition material Em is πr 2 ×650mm 3By setting the rate to 3 / min or higher, even if the tip Em1 of the deposition material Em in the cavity 31a does not melt in time and a sliding phenomenon occurs in one direction forward from the impact position Ip, the tip Em1 will be locked in the locking groove 71 as quickly as possible, and further sliding in the X-axis direction forward within the cavity 31a will be suppressed. In other words, further sliding in one direction forward within the cavity 31 will be suppressed. At this time, there is molten deposition material Em with a locally increased volume in the locking groove 71. Therefore, if the groove width W2 of the locking groove 71 and the groove depth D1 from the bottom surface of the cavity 31 are set so that the effective length of liquid-phase heating is 3 or more, even when the power supply Ps is operated at 90% or more of its rated power capacity, heat conduction is improved and the melting of the deposition material Em is promoted (i.e., the deposition material Em is reliably melted), and as a result, the occurrence of further sliding is suppressed as much as possible. To rephrase this statement using a different technical concept, a liquid-phase heating effective length of 3 or more is correlated with the minimum area of ​​the rectangular shape represented by the groove width W2 of the locking groove 71 and the groove depth D1 from the bottom surface of the cavity 31. Furthermore, the maximum area of ​​this rectangular shape is correlated with the rated current capacity of the power supply Ps. Within this minimum and maximum area range, the desired deposition rate can be achieved without causing slippage, even when operating at more than 90% of the rated power capacity of the power supply Ps, which was impossible with conventional configurations. In other words, stable film deposition can be achieved at a high deposition rate, and furthermore, costs can be reduced by using a power supply Ps with a limited rated power capacity.

[0022] To confirm the above effects, the following experiment was conducted using the vacuum deposition apparatus EM shown in Figure 1. Specifically, the evaluation deposition boat 3 was made by mixing BN and TiB2 as the main raw materials and AlN and WC as additives in a predetermined weight ratio and sintering them (external dimensions: 38 mm × 150 mm × thickness 9 mm). However, no sliding locking grooves 71 were provided in the cavity 31a (corresponding to the conventional deposition boat). The deposition conditions were set to supply power to the deposition boat at 9 kW to 14 kW (heating temperature of deposition boat at approximately 1600°C), and the outer diameter of the Cu deposition material Em was set to 1.5 mm (r = 0.75 mm). The deposition material Em was then fed from the feed roller 62 at a predetermined supply speed in the vacuum chamber 1 under a vacuum atmosphere and deposited onto the substrate Sg. At this time, the pressure inside the vacuum chamber 1 during deposition was 5 × 10⁻⁶ -3 The pressure was maintained at Pa. In preliminary experiments, the supply rate of the deposition material Em was increased by 50 mm / min increments within the range of 500 mm / min to 750 mm / min, and the occurrence of slippage of the deposition material Em was visually confirmed. According to these findings, no slippage occurred and deposition was successful up to a supply rate of 600 mm / min, but it was confirmed that slippage occurred when the supply rate exceeded 650 mm / min.

[0023] Next, as Invention Experiment 1, a deposition boat 3 with a rectangular locking groove 71 recessed in the bottom surface of the cavity 31a was used, and the deposition material Em was supplied so that the impact position Ip of the deposition material Em was contained within the bottom surface of the locking groove 71. In this case, the outer diameter of the Cu deposition material Em was set to 1.5 mm (r=0.75 mm). The Y-axis length W1 of the locking groove 71 was set to 28 mm, and the X-axis groove width W2 was set to 5.0 mm. The deposition conditions were set to supply power to the deposition boat 3 at 13 kW and a supply rate of 650 mm / min (the supply rate expressed as volume per unit time is π × 0.75). 2 ×650mm 3 / min ≈ 1148mm 3(Note that the supply rate can be expressed as volume per unit time using the same formula), the rates were set to 700 mm / min and 750 mm / min, respectively. Then, the groove depth D1 was changed in increments of 0.5 mm in the range of 0.5 mm to 4.0 mm, and the material was deposited onto the substrate Sg. The presence or absence of slippage was visually confirmed, and the results are shown in Table 1. In Table 1, "○" indicates that no slippage of the deposition material Em occurred and the desired deposition rate was obtained, "△" indicates that no slippage of the deposition material Em occurred but the rated current capacity of the power supply Ps was exceeded (i.e., the desired deposition rate could not be obtained), and "×" indicates that the wall surface 71b of the locking groove 71 was overcome and slippage occurred again. According to this, it was confirmed that when the groove depth D1 is 1.0 mm, the deposition material Em can be reliably dissolved in the cavity 31a up to a supply rate of 650 mm / min, and when the groove depth D1 is 1.5 mm, the deposition material Em can be reliably dissolved in the cavity 31a up to a supply rate of 700 mm / min, allowing for stable film formation at a high deposition rate. At this time, it was confirmed that the effective length of liquid-phase heating is 3 or more when the groove depth D1 is 1.0 mm or more. [Table 1]

[0024] Next, as Invention Experiment 2, a deposition boat 3 with a rectangular locking groove 71 recessed in the bottom surface of the cavity 31a was used, and the deposition material Em was supplied so that the impact position Ip of the deposition material Em was contained within the bottom surface of the locking groove 71. In this case, the outer diameter of the Cu deposition material Em was set to 1.5 mm (r=0.75). The length W1 in the Y-axis direction of the locking groove 71 was 28 mm, and the groove width W2 in the X-axis direction was 3.0 mm. For the deposition conditions, the power supplied to the deposition boat 3 was set to 13 kW, and the supply speed was set to 650 mm / min, 700 mm / min, and 750 mm / min, respectively. Then, the groove depth D1 was changed in increments of 0.5 mm in the range of 0.5 mm to 4.0 mm, and deposition was carried out on the substrate Sg, and the presence or absence of slippage was visually confirmed and evaluated as "○", "△", and "×" as above. As shown in Table 2, it was confirmed that when the groove depth D1 is 1.5 mm, the deposition material Em can be reliably dissolved in the cavity 31a up to a supply rate of 650 mm / min, and when the groove depth D1 is 2.0 mm, the deposition material Em can be reliably dissolved in the cavity 31a up to a supply rate of 750 mm / min, allowing for stable film formation at a high deposition rate. At this time, it was confirmed that the effective length of liquid-phase heating is 3 or more when the groove depth D1 is 1.5 mm or more. [Table 2]

[0025] Next, as Invention Experiment 3, a deposition boat 3 was used, which had a rectangular locking groove 71 recessed in the bottom surface of the cavity 31a. The deposition material Em was supplied so that the impact position Ip of the deposition material Em was contained within the bottom surface of the locking groove 71. In this case, the outer diameter of the Cu deposition material Em was set to 1.5 mm (r=0.75). The Y-axis length W1 of the locking groove 71 was 28 mm, and the X-axis groove width W2 was 7.0 mm. For the deposition conditions, the power supplied to the deposition boat 3 was set to 13 kW, and the supply speed was set to 650 mm / min, 700 mm / min, and 750 mm / min, respectively. Then, the groove depth D1 was changed in increments of 0.5 mm in the range of 0.5 mm to 3.0 mm, and deposition was performed on the substrate Sg. The presence or absence of slippage was visually confirmed and evaluated as "○", "△", and "×" as described above. As shown in Table 3, it was confirmed that when the groove depth D1 is 1.0 mm, the deposition material Em can be reliably dissolved in the cavity 31a up to a supply rate of 650 mm / min, and when the groove depth D1 is 1.5 mm, the deposition material Em can be reliably dissolved in the cavity 31a up to a supply rate of 700 mm / min, allowing for stable film formation at a high deposition rate. At this time, it was confirmed that the effective length of liquid-phase heating is 3 or more when the groove depth D1 is 1.0 mm or more. [Table 3]

[0026] Next, as Invention Experiment 4, a deposition boat 3 with a rectangular locking groove 71 recessed in the bottom surface of the cavity 31a was used, and the deposition material Em was supplied so that the impact position Ip of the deposition material Em was contained within the bottom surface of the locking groove 71. In this case, the outer diameter of the Cu deposition material Em was set to 2.0 mm (r=1.0). The Y-axis length W1 of the locking groove 71 was set to 28 mm, and the X-axis groove width W2 was set to 5.0 mm. For the deposition conditions, the power supplied to the deposition boat 3 was set to 13 kW, and the supply speed was set to 370 mm / min, 400 mm / min, and 420 mm / min, respectively. Then, the groove depth D1 was changed in increments of 0.5 mm in the range of 0.5 mm to 4.0 mm, and deposition was carried out on the substrate Sg. The presence or absence of slippage was visually confirmed and evaluated as "○", "△", and "×" as described above. As shown in Table 4, it was confirmed that when the groove depth D1 is 1.0 mm, the deposition material Em can be reliably dissolved in the cavity 31a up to a supply rate of 370 mm / min, and when the groove depth D1 is 1.5 mm, the deposition material Em can be reliably dissolved in the cavity 31a up to a supply rate of 400 mm / min, allowing for stable film formation at a high deposition rate. In this case, when the groove depth D1 is 1.0 mm, the effective length of liquid-phase heating was approximately 2.5, but since the tip portion Em1 should partially melt before being locked in the locking groove 71, increasing the value of the heating circumference ratio, it is assumed that the effective length of liquid-phase heating is 3 or more. [Table 4]

[0027] Next, as Invention Experiment 5, a deposition boat 3 with a rectangular locking groove 71 recessed in the bottom surface of the cavity 31a was used, and the deposition material Em was supplied so that the impact position Ip of the deposition material Em was contained within the bottom surface of the locking groove 71. In this case, the outer diameter of the Cu deposition material Em was set to 2.0 mm (r=1.0). The Y-axis length W1 of the locking groove 71 was set to 28 mm, and the X-axis width W2 was set to 5.0 mm. For the deposition conditions, the power supplied to the deposition boat 3 was set to 18 kW, and the supply speed was set to 600 mm / min, 700 mm / min, and 800 mm / min, respectively. Then, the groove depth D1 was changed in increments of 0.5 mm in the range of 0.5 mm to 4.0 mm, and deposition was performed on the substrate Sg, and the presence or absence of slippage was visually confirmed and evaluated as "○", "△", and "×" as described above. As shown in Table 5, it was confirmed that when the groove depth D1 is 1.0 mm, the deposition material Em can be reliably dissolved in the cavity 31a up to a supply rate of 600 mm / min, and when the groove depth D1 is 1.5 mm, the deposition material Em can be reliably dissolved in the cavity 31a up to a supply rate of 700 mm / min, allowing for stable film formation at a high deposition rate. In this case, when the groove depth D1 is 1.0 mm, the effective length of liquid-phase heating was approximately 2.5, but since the tip portion Em1 should partially melt before being locked in the locking groove 71, increasing the value of the heating circumference ratio, it is assumed that the effective length of liquid-phase heating is 3 or more. [Table 5]

[0028] Although embodiments of the present invention have been described above, various modifications are possible as long as they do not deviate from the technical concept of the present invention. In the above embodiments, an example was given of a locking groove 71 having a strip-shaped contour in plan view, but there are no particular limitations as long as it can reliably lock the tip portion Em1 of the vapor-deposited material Em supplied with a predetermined impact accuracy when a slip phenomenon occurs, and for example, a circular or arch-shaped contour can be adopted. Also, in the above embodiments, an example was given in which the slip suppression part 7 is composed of a single locking groove 71 and the impact position Ip of the vapor-deposited material Em is contained within the bottom surface 71a of the locking groove 71, but it is not limited to this. The locking groove 71 only needs to be located forward in the X-axis direction from the impact position Ip, and the tip portion Em1 of the vapor-deposited material Em sliding on the bottom surface of the cavity 31a can be dropped into the locking groove 71 and locked.

[0029] As described above, depending on the shape of the locking groove 71 (for example, the groove's contour and depth), the material may slip again after overcoming the front wall surface 71b in one direction. Therefore, as shown in the modified deposition boat 3 in Figures 4(a) and 4(b), multiple locking grooves 711, 712 can be provided at intervals in one direction (two in this modified example) (in Figure 4, the same reference numerals are used for the same members and parts as in the above embodiment). This allows the tip of the deposition material Em1 to be locked in the other locking groove 712 even if the material slips again after overcoming the front wall surface 71b in one direction. When multiple locking grooves 711, 712 are provided, the amount of molten metal in the cavity 31a increases, so the groove length W1, groove width W2, and groove depth D1 of each locking groove 711, 712 should be set considering the total volume of the locking grooves 711, 712. For example, if two locking grooves 711 and 712 are provided, the volume of each locking groove 711 and 712 should be set to half the volume of a single locking groove 71.

[0030] Furthermore, although the above embodiment described an example in which the slip-preventing portion 7 is composed of a locking groove 71, it is not limited to this as long as it can reliably lock the leading edge portion Em1 of the vapor-deposited material Em. Referring to Figure 5(a), in the modified slip-preventing portion 7, inclined portions 72F and 72R are provided on the bottom surface of the cavity 31a, respectively, with an upward slope in the front and rear directions in the X-axis direction from the impact position Ip (in Figure 5(a), the same reference numerals are used for the same members and parts as in the above embodiment). The inclined portions 72F and 72R extend to the front and rear ends of the cavity 31a, respectively, and the inclination angle α2 of the inclined portions 72F and 72R with respect to the horizontal plane is appropriately set in the range of 0.5° to 2° depending on the outer diameter of the vapor-deposited material Em, etc. As a result, even if a sliding phenomenon occurs in the deposited material Em, the tip Em1 frictionally engages with the inclined portion 72F extending forward in the X-axis direction from the impact position Ip, suppressing further sliding forward in the X-axis direction within the cavity 31a. At this time, the tip Em1 remaining within the cavity 31a is melted by heat applied from the inclined portion 72F, which is the bottom surface of the cavity 31a. In other words, by providing an inclination angle α2, the surface pressure at the impact position Ip increases, thereby improving frictional engagement with the deposited material Em and low-resistance heat transfer, which can lead to melting. In this case, as shown in Figure 5(b), a locking groove 71 can also be formed forward in the X-axis direction from the impact position Ip. Furthermore, although the above modification was explained using a continuous upward-sloping inclined portion 72F, 72R as an example, it is not limited to this, and although not specifically illustrated and explained, it is also possible to configure it by providing multiple upward-sloping stepped portions at predetermined intervals in the X-axis direction. In any case, the configuration should be such that the melting is promoted by increasing the surface pressure at the point of impact Ip, and one example of such a configuration is one in which the inclination angle is continuously changed.

[0031] Incidentally, as mentioned above, when the deposition boat 3 is held in place by being pressed horizontally by a pair of electrode clamps 5, 5, the deposition boat 3 itself may tilt due to thermal expansion during resistance heating, etc. When the deposition boat 3 tilts, the surface area of ​​the molten metal Mm in the cavity 31a changes accordingly, causing the deposition rate to fluctuate. Moreover, if the deposition boat 3 tilts significantly and the molten metal leaks out of the cavity 31a and comes into contact with, for example, the electrode clamps 5, 5, the temperature of the deposition boat 3 decreases, which reduces the deposition rate. Therefore, as in the modified example above, if inclined portions 72F and 72R are formed symmetrically in one direction, forward and backward from the impact position Ip, respectively, in addition to the function of suppressing the slippage of the deposition material Em in the inclined portions 72F and 72R, the molten metal Mm in the cavity 31a can be constantly collected starting from the impact position Ip. Therefore, problems such as molten metal Mm leaking out from the cavity 31a and coming into contact with the electrode clamps 5,5 do not occur.

[0032] In the above embodiment, a ceramic deposition boat 3 was used as an example, but the invention is not limited to this, and a graphite deposition boat heated by induction heating (especially one with PBN coated on its inner surface) can be used. Furthermore, prior to deposition, an additive metal material (not shown) consisting of at least one metal element from titanium, zirconium, and vanadium and formed into a strip with a thickness in the range of 0.5 mm to 2 mm can be prepared, and the additive metal material can be placed on the inner bottom surface of the cavity 31a so that when the deposition material Em melts due to heating of the deposition boat 3, the additive metal material comes into contact with the molten metal and dissolves into the molten deposition material Em. This promotes wettability by the additive metal material dissolving into the molten deposition material Em, dramatically improving the film deposition rate. [Explanation of Symbols]

[0033] EM... Vacuum deposition apparatus, Em... Deposition material (wire-shaped copper), Em1... Tip of the deposition material, Sg... Substrate (object to be deposited), 1... Vacuum chamber, 3... Deposition boat, 31a... Cavity, 5... Electrode clamp, 6... Material supply means, 71, 711, 712... Locking groove, 71a... Bottom surface of the locking groove, 71b... Wall surface in one direction forward of the locking groove, 72F, 72R... Inclined portion, Ip... Impact position, Ps... Power supply (heating means), W2... Groove width of the locking groove, D1... Groove depth of the locking groove.

Claims

1. A vacuum deposition apparatus comprising a deposition boat made by sintering raw materials mainly composed of boron nitride and titanium boride, installed in a vacuum chamber; a power supply for energizing the deposition boat; and a material supply means for supplying wire-shaped deposition material mainly composed of Cu and having a radius r in the range of 0.5 to 2 mm, wherein the wire-shaped deposition material is continuously supplied from one direction to the cavity of the deposition boat, which is heated by the energization, and a predetermined thin film is deposited on an object to be deposited in the vacuum chamber by dissolving and evaporating the deposition material in the cavity. In a material supply means, the position where the tip of the deposition material contacts the bottom surface of the cavity is defined as the impact position, and the device has a locking groove recessed in the bottom surface of the cavity one direction forward of the impact position to lock the tip of the deposition material that slides forward in one direction, The amount of material supplied per unit volume by the material supply means is πr ２ ×650mm ３ A vacuum deposition apparatus characterized in that, when set to / min or higher and the power supply is operated at 90% or more of its rated power capacity, the groove width of the locking groove and the groove depth from the bottom surface of the cavity are set so that the effective length of liquid-phase heating is 3 or more.

2. The vacuum deposition apparatus according to claim 1, characterized in that a plurality of the locking grooves are provided at intervals in one direction.

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