JP5049632B2 - Filament fixing mechanism, heating mechanism and vapor deposition device - Google Patents

Description

  The present invention relates to a vapor deposition apparatus that deposits a predetermined substance on the surface of a deposition substrate, and a heat generation mechanism and a filament fixing mechanism used for an evaporation source in such a vapor deposition apparatus.

  Conventionally, in fabricating thin film structures included in various electronic devices and optical devices, physical vapor deposition (PVD), chemical vapor deposition (CVD), etc. Thin film formation technology is used.

  Physical vapor deposition methods include a vacuum evaporation method in which a target (evaporation source) is heated to vaporize and evaporate, a sputtering method in which an inert gas is turned into a plasma by glow discharge or high frequency, and the target is sputtered. Examples of the potential include an ion plating method in which an ionized target is deposited on a substrate. The sputtering method can finely adjust the film thickness, but has a problem in mass production because the deposition rate is slow. In the ion plating method, since the temperature of the substrate rises, the substrate material is limited, and there is a problem that fine processing using a mask cannot be performed.

The vacuum deposition method is classified into a resistance heating method, a high frequency induction heating method, a laser deposition method, an electron beam deposition method, and the like depending on the heating method. In recent years, it has the characteristics that it can be deposited by vapor deposition regardless of whether it is a conductor such as metal or non-conductor, and it can be deposited with relatively fine film quality. The law is frequently used. In this electron beam evaporation method, generally, a target substance (evaporation substance as a material of a thin film to be produced) is hit with an electron beam and physically heated and melted, and a part thereof is sublimated to form a film. A thin film made of a desired substance is formed by depositing on the surface of a target evaporation target substrate. The generation of an electron beam is often performed by causing a current to flow through a filament mainly composed of tungsten (W) to emit thermal electrons. For example, Patent Document 1 discloses a film forming apparatus that performs such electron beam evaporation.
Japanese Patent Application Laid-Open No. 2004-131782

  By the way, such a filament is generally energized by gripping both ends thereof by a pair of metal members. 8 and 9 show an example of a conventional fixture for gripping the end of the filament. FIG. 8 is a perspective view showing the configuration of the main part of the fixture, and FIG. 9 is a cross-sectional view in the direction of the arrow along the IX-IX cutting line shown in FIG. The fixture includes a base 110 and a pressing member 120 that are opposed to each other with an end portion of the filament 150 interposed therebetween, and two bolts 140 that fix the pressing member 120 to the base 110. The base 110 is provided with two screw holes 111, and the holding member 120 is provided with two openings 121 at positions corresponding to the two screw holes 111, respectively. An engagement portion 122 having an inner diameter smaller than the diameter of the head of the bolt 140 is provided on a part of the inner surface of the opening 121. The bolt 140 passes through the opening 121, and its threaded portion is fitted into the screw hole 111. Here, since the head of the bolt 140 is engaged with the engaging portion 122 of the opening 121 by turning the bolt 140 in the tightening direction, the base 110 and the pressing member 120 are fastened. As a result, the end of the filament 150 sandwiched between the base 110 and the pressing member 120 is fixed.

  However, with the fixtures as shown in FIGS. 8 and 9, it is difficult to fasten the two bolts 140 with equal force. For this reason, the imbalance of the fastening force due to the two bolts 140 is likely to occur, and in some cases, the contact between the end of the filament 150 and the surface of the base 110 becomes insufficient, which may increase the contact resistance. Further, even if the two bolts 140 are tightened once with an appropriate and equal force, the bolts 140 expand due to the heat generation of the filament 150. The fastening force may be reduced, leading to an increase in contact resistance. Thus, if the contact resistance at the contact surface between the filament and the fixture is increased, the fixture may be melted and fused with the filament. Therefore, an improvement has been desired.

  The present invention has been made in view of such problems, and an object of the present invention is to provide a filament fixing mechanism capable of sufficiently fixing a filament without fusing with the filament, and a heat generating mechanism and a vapor deposition apparatus including the filament fixing mechanism. It is to provide.

The filament fixing mechanism of the present invention grips the end portion of the filament, and is provided with the constituent elements shown in the following (A1) to (A3).
(A1) An electrode having a contact surface in contact with the end of the filament.
(A2) A pressing plate arranged so that the end of the filament is sandwiched between the contact surfaces of the electrodes.
(A3) Biasing means for pressing at least a part of the region of the pressing plate corresponding to the end of the filament toward the contact surface.
Here, “region corresponding to the end portion of the filament in the pressing plate” means a region of the pressing plate that overlaps with the end portion of the filament when projected in the biasing direction by the biasing means.

  The heat generating mechanism of the present invention includes a filament and a filament fixing mechanism that holds both ends of the filament. The filament fixing mechanism has the constituent elements shown in the above (A1) to (A3). Furthermore, the vapor deposition apparatus of the present invention is provided with an evaporation source having such a heat generating mechanism.

  In the filament fixing mechanism, the heat generating mechanism, and the vapor deposition apparatus of the present invention, the pressing plate and the electrode are pressed by pressing at least a part of the region corresponding to the end of the filament in the pressing plate toward the contact surface. Since the end of the filament is gripped by the contact surface, a good contact state between the end of the filament and the contact surface of the electrode can be easily realized.

  In the filament fixing mechanism, the heat generating mechanism, and the vapor deposition apparatus of the present invention, the electrode is disposed so as to sandwich the first member having the contact surface and the end of the filament and the pressing plate between the contact surface and the attachment. And a second member for holding the biasing means. In that case, each of the first and second members has an engaging portion that engages with each other by the urging force of the urging means. Moreover, a favorable contact state is more stably maintained by providing 2 sets of engaging parts on both sides of a filament. In addition, it is desirable that the contact surface where the engaging portion of the first member and the engaging portion of the second member contact each other is inclined with respect to the urging direction by the urging means. By having such an inclination, a shift between the first member and the second member in a direction orthogonal to the urging direction by the urging means is less likely to occur.

  In the filament fixing mechanism, the heat generating mechanism, and the vapor deposition apparatus of the present invention, for example, a bolt that fits into a fitting hole (screw hole) provided in a part of the biasing means can be adopted. In that case, the tip of the bolt is located in a region overlapping with the contact surface.

  In the filament fixing mechanism, the heat generating mechanism, and the vapor deposition apparatus of the present invention, it is desirable that the contact area between the pressing plate and the filament end and the contact area between the electrode contact surface and the filament end are equal to each other. By doing so, a stress with a smaller bias is applied over the entire contact area between the contact surface of the electrode and the end of the filament.

  According to the filament fixing mechanism of the present invention, the pressing plate and the contact surface of the electrode are pressed by the urging means by pressing at least a part of the region corresponding to the end of the filament in the pressing plate toward the contact surface of the electrode. Since the end of the filament is gripped, the contact resistance between the end of the filament and the contact surface of the electrode can be reliably reduced. As a result, the filament can be mechanically and firmly fixed without causing fusion with the filament.

  Therefore, according to the heat generating mechanism using such a filament fixing mechanism, stable heat generation can be performed for a longer time. In addition, the life of the filament can be extended. Furthermore, according to the vapor deposition apparatus equipped with such a heat generating mechanism, it is possible to perform a stable vapor deposition process for a longer time, and to improve the production efficiency.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a schematic configuration of an electron beam vapor deposition apparatus as an embodiment of the present invention. This electron beam vapor deposition apparatus includes a crucible 2, a crucible cooling system 3, an electron gun 4, a shutter 5, a monitor 6, a heater 8, a substrate holder 9, a vacuum measuring instrument 10, and a holder rotating mechanism 11. It has. However, a part of the holder rotating mechanism 11 is provided outside the vapor deposition processing container 1. A vacuum exhaust system 12, a control circuit system 13, and a power supply circuit system 14 are provided outside the vapor deposition processing container 1. This electron beam evaporation apparatus evaporates the evaporation material 15 (described later) accommodated in the crucible 2 and deposits it on the surface of the evaporation target substrate 16 (described later) held by the substrate holder 9. To form.

  The crucible 2 contains the deposition material 15 and is made of, for example, titanium oxide, tantalum oxide, zirconium oxide, silicon oxide, or the like. A part of the periphery of the crucible 2 is covered with a crucible cooling system 3. The crucible cooling system 3 is cooled in order to protect it from excessive temperature rise of the crucible 2 due to the irradiation of the electron beam to the vapor deposition material 15. Specifically, for example, a water-cooling type cooling device such as a water jacket is used. Etc. are suitable.

  The electron gun 4 has a filament 4A mainly made of tungsten (W), a pair of fixing mechanisms 4B for fixing the filament 4A, and a gun member 4C provided with an electron emission hole and covering the filament 4A. And as a main part thereof. The electron gun 4 is set so that when power is supplied from an external power supply circuit system 14, the filament 4A is red hot and emits thermoelectrons. The thermoelectrons emitted from the electron gun 4 are irradiated onto the vapor deposition material 16 accommodated in the crucible 2 with the range controlled electromagnetically by a deflection yoke (not shown), for example. The vapor deposition material 15 is heated by irradiation of thermoelectrons from the electron gun 4 and melts and then gradually evaporates (vaporizes). The crucible 2 containing the deposition material 15 and the electron gun 4 correspond to the evaporation source of the present invention.

  The shutter 5 is a member that is disposed between the crucible 2 and the deposition target substrate 16 held by the substrate holder 9 and can be opened and closed to control the passage of the deposition material 15 from the crucible 2 toward the deposition target substrate 16. That is, the vapor deposition material 15 is opened during the vapor deposition process and allows the gaseous vapor deposition material 15 evaporated from the crucible 2 to pass therethrough, while before and after the vapor deposition process, the gaseous vapor deposition material 15 passes through the crucible 2. Is to shut off. The shutter 5 is connected to the control circuit system 13 and is driven when a command signal for opening or closing is input.

  The monitor 6 is for observing the evaporation rate of the vapor deposition material 15 evaporating from the crucible 2 and is, for example, a crystal monitor using a change in the frequency of the crystal. In the monitor 6, a sensor unit (not shown) is made of quartz, and the evaporation rate is calculated based on a change in the vibration frequency of the quartz accompanying the deposition material 15 adhering to the surface.

  The heater 8 heats the deposition target substrate 16 to a predetermined temperature, for example, for the purpose of improving the durability of the thin film formed on the surface of the deposition target substrate 16.

  The substrate holder 9 mechanically holds the deposition target substrate 16 on which the deposition material 15 is deposited. In this electron beam vapor deposition apparatus, a plurality of substrate holders 9 are provided, and a vapor deposition substrate 16 is attached to each.

  The holder rotating mechanism 11 rotates the substrate holder 9 in order to avoid positional deviation of the deposit during the vapor deposition process. The holder rotating mechanism 11 has a support portion 11A that supports the substrate holder 9, a drive portion 11C that functions as a drive force source such as an electric motor, and a support shaft 11B that transmits the power of the drive portion 11C to the support portion 11A. ing. That is, each substrate holder 9 (and the deposition target substrate 16) revolves around the support shaft 11B as a rotation center.

  The vacuum exhaust system 12 is for sucking from the exhaust pipe 12A and evacuating the inside of the vapor deposition processing container 1 to a predetermined degree of vacuum. The degree of vacuum inside the vapor deposition processing container 1 is measured by the vacuum degree measuring instrument 10. The vapor deposition processing vessel 1 is provided with a gas inlet (not shown).

  The control circuit system 13 issues a command signal to the shutter 5 to control the opening / closing operation of the shutter 5, and issues a command signal to the power supply circuit system 14 to control the evaporation amount of the deposition material 15 from the crucible 2. And a function of controlling the vacuum exhaust system 12.

  Specifically, when starting the vapor deposition process, the control circuit system 13 drives the evacuation system 12 to evacuate the interior of the vapor deposition process container 1 and then issues a command signal to the power supply circuit system 14. It functions to supply power to the filament 4A to emit thermoelectrons and to start evaporation of the deposition material 15. In addition, the control circuit system 13 adjusts the amount of released thermoelectrons from the filament 4A via the power supply circuit system 14 based on the evaporation rate data from the monitor 6, so that the vapor deposition material 15 from the crucible 2 is controlled. It also has a function of controlling the evaporation rate.

  Next, the configuration of the fixing mechanism 4B will be described in detail with reference to FIG. 2 and FIG. FIG. 2 is a perspective view (combination drawing) showing the overall configuration of the fixing mechanism 4B, and FIG. 3 is an exploded perspective view of the fixing mechanism 4B.

  The fixing mechanism 4B is disposed so as to face the end 4AT of the filament 4A, and includes first and second members 20 and 30 each having an engagement portion that engages with each other, and the first and second members together with the end 4AT of the filament 4A. A holding plate 40 sandwiched between the second members 20 and 30 and a bolt 50 for fastening the second member 30 to the first member 20 are provided. The first and second members 20 and 30, the pressing plate 40, and the bolt 50 are all made of, for example, a metal material. 4 to 6 show the first member 20, the second member 30, and the holding plate 40, respectively. FIGS. 4 (A) to 4 (C) are the first member. FIG. 5A to FIG. 5C sequentially represent a plan view, a side view, and a front view of the second member 30, and FIG. -FIG.6 (C) represents the top view, side view, and front view of the pressing board 40 in order.

  The first member 20 includes a support column 21 having an upper surface 21A, arm portions 22 and 23 arranged so as to sandwich the support column 21 on the upper surface 21A side, and a support column 21 on the opposite side of the upper surface 21A. The leg portions 24 and 25 disposed so as to face each other are integrated. The column 21 has a prismatic shape extending in the tightening direction (Z-axis direction) of the bolt 50, and a part of the upper surface 21A thereof is a contact region 21S in contact with the end 4AT of the filament 4A (see FIG. 3). ). The arm portions 22 and 23 protrude from the support column 21 in the direction (Y-axis direction) intersecting the direction in which the pressing plate 40 is urged by the bolt 50 (the tightening direction of the bolt 50). The upper surfaces 22A and 23A of the arm portions 22 and 23 form a common plane together with the upper surface 21A of the column portion 21. The surfaces of the arm portions 22 and 23 opposite to the upper surfaces 22A and 23A are contact surfaces 22T and 23T that contact a part of the second member 30. The contact surfaces 22T and 23T are inclined with respect to the tightening direction of the bolt 50.

  The second member 30 has a screw hole 31K substantially at the center and a flat plate portion 31 having a substantially flat plate shape, and flange portions 32 and 33 erected at both ends of the flat plate portion 31. is there. The collar portions 32 and 33 have arm portions 32A and 33A and claw portions 32B and 33B provided at the tips thereof. The claw portions 32B and 33B have contact surfaces 32T and 33T that contact the contact surfaces 22T and 23T of the first member 20, respectively. It is desirable that the contact surfaces 22T and 23T and the contact surfaces 32T and 33T have the same inclination angle.

  The holding plate 40 is a flat plate-like member provided with a cylindrical inner surface groove 41 that fits the tip of the bolt 50 at the center thereof. The planar shape of the pressing plate 40 is, for example, the same shape as the upper surface 21A of the first member 20. When the front end of the bolt 50 is accommodated in the groove 41, it is possible to prevent the pressing plate 40 from being detached from the predetermined position in the horizontal direction.

  The fixing mechanism 4 </ b> B made of such components rotates the bolt 50 held by the second member 30 in the tightening direction, so that the pressing plate 40 is pressed in the direction toward the support column 21 (−Z direction). At this time, the claw portions 32B and 33B of the second member 30 engage with the arm portions 22 and 23 of the first member 20, and the contact surfaces 32T and 33T and the contact surfaces 22T and 23T come into contact with each other. Therefore, by further rotating the bolt 50 in the tightening direction, the end portion 4AT of the filament 4A is sufficiently firmly held by the pressing plate 40 and the upper surface 21A of the column portion 21.

  As described above, according to the present embodiment, the bolt 50 presses a part of the region corresponding to the contact region 21S (the region corresponding to the filament end 4AT) on the pressing plate 40 toward the upper surface 21A. Thus, since the end plate 4AT of the filament 4A is gripped by the pressing plate 40 and the upper surface 21A, a good contact state between the end portion 4AT and the upper surface 21A can be easily realized. Therefore, the contact resistance between the filament 4A and the first member 20 can be reliably reduced. In addition, it is possible to efficiently dissipate heat while reducing heat generation near the upper surface 21A. As a result, the fixing mechanism 4B can mechanically and sufficiently fix the filament 4A without causing fusion between the respective members and the filament 4A.

  Therefore, according to the electron gun 4 as a heat generating mechanism using such a fixing mechanism 4B, stable heat generation can be performed for a longer time. Further, the life of the filament 4A can be extended. Furthermore, according to the vapor deposition apparatus of the present embodiment in which such an electron gun 4 is mounted, it is possible to perform a vapor deposition process that is stable for a longer time and to improve the production efficiency.

  Here, when the contact area between the pressing plate 40 and the end portion 4AT and the contact area 21S on the contact surface 21A coincide with each other, a stress with a smaller bias is applied over the entire surface of the contact area 21S. Therefore, it is more preferable.

  While the present invention has been described with reference to the embodiment, the present invention is not limited to the above embodiment, and various modifications can be made. For example, in the above embodiment, thermoelectrons are taken out by heating a deposition material using an electron gun, but the present invention is not limited to this, and a resistance heating method, a high frequency induction heating method, or the like is used. It can also be adopted.

  Furthermore, in the above-described embodiment, the electrode is configured by the first and second members 20 and 30 divided from each other. However, the present invention is not limited to this. For example, an integrated base 60 having an opening 60K may be used as in the modification shown in FIG. However, by dividing the electrode into the first member 20 and the second member 30 as in the above embodiment, the polishing and cleaning operations for maintaining the smooth state of the upper surface 21A are facilitated. Therefore, it is preferable.

It is a schematic block diagram of the electron beam vapor deposition apparatus as one embodiment in this invention. It is a perspective view (combination drawing) showing the whole structure of the fixing mechanism shown in FIG. It is a disassembled perspective view showing the whole structure of the fixing mechanism shown in FIG. It is the top view showing the structure of the 1st member 20 which comprises the fixing mechanism shown in FIG. 1, the front view, and the side view. It is the top view showing the structure of the 2nd member 30 which comprises the fixing mechanism shown in FIG. 1, the front view, and the side view. FIG. 2 is a plan view, a front view, and a side view illustrating a configuration of a pressing plate 40 configuring the fixing mechanism illustrated in FIG. 1. It is a perspective view showing the whole structure in the modification of the fixing mechanism shown in FIG. It is a perspective view showing the structure of the conventional fixing mechanism. It is sectional drawing of the conventional fixing mechanism shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Deposition processing container, 2 ... Crucible, 3 ... Crucible cooling system, 4 ... Electron gun, 4A ... Filament, 4AT ... End part, 4B ... Fixing mechanism, 4C ... Gun member, 5 ... Shutter, 6 ... Monitor, 8 ... Heater, 9 ... Substrate holder, 10 ... Vacuum degree measuring device, 11 ... Holder rotating mechanism, 12 ... Vacuum exhaust system, 13 ... Control circuit system, 14 ... Power supply circuit system, 15 ... Deposition substance, 16 ... Substrate to be deposited, 20 ... 1st member, 21S ... Contact area, 30 ... 2nd member, 40 ... Holding plate, 50 ... Bolt.

Claims (7)

A filament fixing mechanism for holding an end of the filament,
An electrode having a contact surface in contact with an end of the filament;
A holding plate disposed so as to sandwich an end of the filament between the contact surface;
Urging means for pressing at least a part of a region of the pressing plate corresponding to the end of the filament toward the contact surface;
The electrode is a first member having the contact surface, and a second member that is disposed so as to sandwich the end of the filament and the pressing plate between the contact surface and holds the biasing means. Including
The first and second members each have an engagement portion that engages with each other by a pressing operation of the urging means against the pressing plate and fixes the first and second members to each other. Filament fixing mechanism. The filament fixing mechanism according to claim 1 , wherein two sets of the engaging portions are provided with the filament interposed therebetween. The biasing means is a bolt that fits into a fitting hole provided in a part of the second member,
The filament fixing mechanism according to claim 1 or 2 , wherein a tip portion of the bolt is located in a region corresponding to an end portion of the filament. The contact surface where the engaging portion of the first member and the engaging portion of the second member contact each other is inclined with respect to the urging direction by the urging means. The filament fixing mechanism according to any one of claims 1 to 3 . The contact area between the pressing plate and the end of the filament and the contact area between the contact surface of the electrode and the end of the filament are equal to each other.
Filament fixing mechanism according to any one of claims 1 to 4, wherein the arc. Filament,
A heating mechanism comprising: the filament fixing mechanism according to any one of claims 1 to 5 , which grips both ends of the filament. An evaporation apparatus comprising an evaporation source having the heat generating mechanism according to claim 6 .

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