JP3732074B2 - Deposition equipment - Google Patents

Description

[0001]
[Field of the Invention]
The present invention relates to a film forming apparatus for forming a transparent conductive film or the like on a substrate using a plasma beam.
[0002]
[Prior art]
As a film forming apparatus using a plasma beam, for example, there is an ion plating apparatus disclosed in JP-A-9-194232. In this ion plating apparatus, the upper end of a material tablet made of indium and tin oxide (ITO) is guided through a hollow cone-shaped guide member provided in the hearth through a plasma beam from a pressure gradient type plasma gun to the hearth. This is gradually pushed up while sublimating. The evaporating substance emitted from the upper end of the material tablet is ionized in the plasma beam, and the ionized material particles adhere to the surface of the substrate conveyed opposite to the hearth, and an ITO film is formed here.
[0003]
[Problems to be solved by the invention]
In the film forming apparatus as described above, copper having high conductivity and heat conductivity is usually used as the hearth. However, since copper has a property of easily reacting with indium even at a relatively low temperature, the material tablet is a hearth guide member. It may be difficult to push up the material tablet by adhering to the inner surface.
[0004]
On the other hand, if the guide member is excessively cooled, a temperature difference will occur between the center and the periphery of the material tablet, and only the center part of the material tablet may be deeply dug to make stable film formation difficult. .
[0005]
Furthermore, the plasma beam may be incident on the guide member in a biased or concentrated manner. In such a case, the material tablet may be decentered and recessed, and stable film formation may be hindered. .
[0006]
Accordingly, an object of the present invention is to provide a film forming apparatus that prevents the material tablet and the guide member from adhering to each other and prevents the material tablet from being dug unevenly, thereby enabling stable film formation. .
[0007]
[Means for Solving the Problems]
In order to solve the above problems, a film forming apparatus of the present invention includes a plasma source for supplying a plasma beam into a film forming chamber, a hearth disposed in the film forming chamber and guiding the plasma beam, and a film as a material evaporation source in the hearth. A material supply device for continuously supplying a material, wherein the hearth includes an annular guide member having a through-hole through which the film material passes, and the guide member is connected to the outer body layer. And an inner layer formed of a material that is relatively less reactive with the membrane material than the main body layer.
[0008]
In this case, since the guide member has an outer main body layer and an inner layer formed of a material that is relatively less reactive with the film material than the main body layer, the film material is guided during film formation. It is possible to maintain the cooling capacity, conductivity, and the like of the entire guide member while preventing adhesion to the inside of the guide member.
[0009]
Further, another film forming apparatus of the present invention includes a plasma source for supplying a plasma beam into a film forming chamber, a hearth disposed in the film forming chamber for guiding the plasma beam, and a film material as a material evaporation source in the hearth continuously. A material supply device for supplying the material, wherein the hearth includes an annular guide member having a through-hole through which the film material passes, and the guide member includes an outer body layer and the body. And an inner layer formed of a material having a lower thermal conductivity than the layer.
[0010]
In this case, since the inner layer is formed of a material having a lower thermal conductivity than that of the main body layer, heat radiation from the film material to the guide member is relatively gentle, and the temperature of the film material is relatively uniform. Can be maintained at temperature. Therefore, for example, a rod-shaped film material can be dug at a relatively uniform depth, and uniform, stable and rapid film formation becomes possible.
[0011]
In a preferred aspect of the above device, the inner layer is formed of a material having a relatively higher heat resistant temperature than the main body layer.
[0012]
In this case, since the inner layer is formed of a material having a relatively high heat resistance temperature than the main body layer, even if the temperature of the film material is relatively high, the guide member may be damaged or the film material and the guide It can prevent that a member reacts.
[0013]
Moreover, in the preferable aspect of the said apparatus, a main body layer consists of copper and an inner side layer consists of stainless steel.
[0014]
In this case, the film material can be effectively prevented from adhering to the inside of the guide member, and the temperature distribution in the film material can be made uniform easily. In addition, since the inner layer is made of stainless steel, which is a magnetic material, the lines of magnetic force are attracted to the magnetic material surrounding the film material near the tip of the guide member, and the plasma beam is compared directly above the tip of the guide member. Will spread evenly. As a result, the upper surface of the film material is heated relatively uniformly, the film material is consumed uniformly, and stable film formation becomes possible.
[0015]
Further, another film forming apparatus of the present invention includes a plasma source for supplying a plasma beam into the film forming chamber, a hearth disposed in the film forming chamber for guiding the plasma beam, and a film material as a material evaporation source for the hearth. A film forming apparatus comprising a material supply device that continuously supplies a hearth comprising an annular guide member having a through-hole through which a film material passes, and a magnetic material provided on an upper outer periphery of the guide member A magnetic member.
[0016]
In this case, since the magnetic member made of a magnetic material is provided on the upper outer periphery of the guide member, the magnetic lines of force are attracted to the magnetic member surrounding the guide member near the tip of the guide member, and the plasma beam is generated immediately above the tip of the guide member. It spreads relatively uniformly. As a result, the upper surface of the film material is heated relatively uniformly, the upper part of the film material is evenly consumed, and stable film formation becomes possible.
[0017]
In a preferred aspect of the above apparatus, the apparatus further comprises a magnet arranged in an annular shape around the hearth, or a magnetic field control member that controls the upper magnetic field close to the hearth, and the plasma source performs arc discharge. This is a pressure gradient type plasma gun.
[0018]
In this case, a film having a more uniform thickness can be formed by correcting the plasma beam incident on the hearth by the magnetic field control member with a cusp-like magnetic field.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
[First Embodiment]
FIG. 1 is a diagram schematically illustrating the overall structure of the film forming apparatus according to the first embodiment. The film forming apparatus includes a vacuum container 10 that is a film forming chamber, a plasma gun 30 that is a plasma source that supplies a plasma beam PB into the vacuum container 10, and a plasma beam PB that is disposed at the bottom of the vacuum container 10. An incident anode member 50 and a transport mechanism 60 that appropriately moves a substrate holding member WH for holding a substrate such as a liquid crystal glass plate to be deposited above the anode member 50 are provided.
[0020]
The plasma gun 30 is a pressure gradient type plasma gun disclosed in Japanese Patent Application Laid-Open No. 9-194232 and the like, and its main body portion is attached to a cylindrical portion 12 provided on the side wall of the vacuum vessel 10. The main body portion is composed of a glass tube 32 whose one end is closed by a cathode 31. In the glass tube 32, a cylinder 33 made of molybdenum Mo is fixed to the cathode 31 and arranged concentrically. In the cylinder 33, a disk 34 made of LaB ₆ and tantalum Ta are formed. The pipe 35 is built in. The first and second intermediate electrodes 41, 42 are concentric between the end of the glass tube 32 opposite to the cathode 31 and the end of the cylindrical portion 12 provided in the vacuum vessel 10. Are arranged in series. In the first intermediate electrode 41, an annular permanent magnet 44 for converging the plasma beam PB is incorporated. An electromagnetic coil 45 for converging the plasma beam PB is also built in the second intermediate electrode 42. A steering coil 47 that guides the plasma beam PB generated on the cathode 31 side and drawn to the first and second intermediate electrodes 41 and 42 into the vacuum vessel 10 is provided around the cylindrical portion 12. .
[0021]
The operation of the plasma gun 30 is controlled by a gun driving device (not shown). Thus, the power supply to the cathode 31 can be turned on / off, the supply voltage to the cathode 31 can be adjusted, and the power supply to the first and second intermediate electrodes 41, 42, the electromagnet coil 45, and the steering coil 47. Can be adjusted. That is, the intensity and distribution state of the plasma beam PB supplied into the vacuum vessel 10 can be controlled.
[0022]
The pipe 35 arranged on the innermost side of the plasma gun 30 is for introducing a carrier gas such as Ar, which is the source of the plasma beam PB, into the plasma gun 30 and thus into the vacuum vessel 10. And is connected to a carrier gas source 90 via a flow rate adjusting valve 94.
[0023]
The anode member 50 disposed in the lower part of the vacuum vessel 10 includes a hearth 51 that is a main anode for guiding the plasma beam PB downward, and an annular auxiliary anode 52 disposed around the anode 51.
[0024]
The former hearth 51 is made of a conductive material and is supported by a grounded vacuum vessel 10 via an insulator (not shown). The hearth 51 is controlled to an appropriate positive potential and sucks the plasma beam PB emitted from the plasma gun 30 downward. The hearth 51 has a through hole 51a in which a rod-shaped material rod 53, which is a material evaporation source, is loaded at the center where the plasma beam PB from the plasma gun 30 is incident. This material rod 53 is obtained by sintering and hardening indium oxide powder and tin oxide powder, which are film materials, and is heated and sublimated by the current from the plasma beam PB to form an ITO film on the substrate. Generate material vapor to form. The material supply device 58 provided in the lower part of the vacuum vessel 10 has a structure in which the material rods 53 are successively loaded into the through holes 51a of the hearth 51 and the loaded material rods 53 are gradually raised. Even if the upper end evaporates and wears, the upper end can always protrude from the recess of the hearth 51 by a certain amount.
[0025]
The latter auxiliary anode 52 is constituted by an annular container disposed concentrically around the hearth 51. In this annular container, an annular permanent magnet 55 made of ferrite or the like and a coil 56 laminated concentrically therewith are accommodated. The permanent magnet 55 and the coil 56 are magnetic field control members, and form a cusp-like magnetic field directly above the hearth 51. Thereby, the direction of the plasma beam PB incident on the hearth 51 can be corrected.
[0026]
The coil 56 in the auxiliary anode 52 constitutes an electromagnet, and is supplied with power from an anode power supply device (not shown) to form an additional magnetic field that has the same direction as the magnetic field on the center side generated by the permanent magnet 55. Thereby, the current supplied to the coil 56 can be changed, and the direction of the plasma beam PB incident on the hearth 51 can be finely adjusted.
[0027]
The container of the auxiliary anode 52 is also made of a conductive material, like the hearth 51. The auxiliary anode 52 is attached to the hearth 51 via an insulator (not shown). By changing the voltage applied to the auxiliary anode 52, the electric field above the hearth 51 can be controlled complementarily. That is, when the potential of the auxiliary anode 52 is made the same as that of the hearth 51, the plasma beam PB is also attracted thereto, and the supply of the plasma beam PB to the hearth 51 is reduced. On the other hand, when the potential of the auxiliary anode 52 is lowered to the same level as that of the vacuum vessel 10, the plasma beam PB is attracted to the hearth 51 and the material rod 53 is heated.
[0028]
The transport mechanism 60 is arranged in the transport path 61 at equal intervals in the horizontal direction and supports a plurality of rollers 62 that support the end portions of the substrate holding member WH, and rotates these rollers 62 at an appropriate speed to rotate the substrate holding member. And a drive device (not shown) that moves the WH at a constant speed.
[0029]
The oxygen gas supply device 71 is for supplying an appropriate amount of oxygen gas to the vacuum vessel 10 at an appropriate timing. A supply line from an oxygen gas source 71a that stores oxygen gas is connected to the vacuum vessel 10 via a flow rate control valve 71b and a flow meter 71c. The carrier gas supply device 72 is for supplying an appropriate amount of carrier gas to the vacuum vessel 10 at an appropriate timing. The carrier gas branched from the carrier gas source 90 is directly introduced into the vacuum vessel 10 through the flow rate adjustment valve 72b and the flow meter 72c of the carrier gas supply device 72. The exhaust device 76 appropriately exhausts the gas in the vacuum vessel 10 through the vacuum gate 76a by the exhaust pump 76b.
[0030]
FIG. 2 is a side sectional view for explaining a more detailed structure of the hearth 51. The hearth 51 includes a base member 151 having a cooling cavity C, and a cone-shaped guide member 251 fixed on the base member 151. The base member 151 and the guide member 251 are fixed so that the centers of the openings 151a and 251a provided in the base member 151 and the guide member 251 coincide with each other. Thereby, a cylindrical through-hole 51 a for feeding the material rod 53 upward is formed in the center of the hearth 51.
[0031]
The base member 151 is made of copper, has high thermal conductivity and conductivity, and is cooled by cooling water supplied to the cavity C.
[0032]
The guide member 251 includes an outer main body layer 251b and an inner layer 251c on the opening 251a side. The former body layer 251b is made of copper, has high thermal conductivity and conductivity, is electrically and mechanically connected to the base member 151, and is maintained at an appropriate potential and temperature. On the other hand, the inner layer 251c is made of, for example, stainless steel such as SUS430 and has high heat resistance. However, the inner layer 251c is somewhat inferior in terms of thermal conductivity and conductivity than the copper main body layer 251b. For this reason, when the material rod 53 is heated by the plasma beam PB, the inner layer 251c acts as a barrier to restrict heat dissipation to some extent, so that the material rod 53 is maintained at a relatively uniform and high temperature. Thus, when the material rod 53 is uniformly heated, the material rod 53 is consumed relatively evenly, and the upper surface 53a of the material rod 53 becomes relatively flat, so that the material rod 53 is uniform and stable. Film formation becomes possible. In addition, the film forming speed can be increased by setting the material rod 53 to a high temperature. Further, since the inner layer 251c is formed of stainless steel, it is difficult to adhere to the inner layer 251c even if the material rod 53 is heated. Further, since the inner layer 251c is formed of stainless steel, the magnetic lines of force are attracted to the inner layer 251c near the tip of the guide member 251, and the magnetic flux density decreases just above the tip of the guide member 251 so that the plasma beam PB is generated. Can be spread. As a result, the upper surface 53a of the material rod 53 is heated relatively uniformly, and stable film formation becomes possible.
[0033]
FIG. 3 is a diagram for conceptually explaining the distribution of the lines of magnetic force in the vicinity of the tip of the guide member 251. As is clear from the figure, the lines of magnetic force incident on the guide member 251 from above converge on the inner layer 251c, which is a magnetic body, so that the magnetic flux density above the guide member 251 decreases uniformly. That is, the plasma beam PB is spread above the guide member 251, and it is possible to prevent digging in which the upper portion of the material rod 53 is unevenly depressed as the film is formed.
[0034]
Hereinafter, the operation of the film forming apparatus shown in FIG. 1 will be described. During film formation by this film formation apparatus, a discharge is generated between the cathode 31 of the plasma gun 30 and the hearth 51 in the vacuum vessel 10, thereby generating a plasma beam PB. The plasma beam PB reaches the hearth 51 while being guided by a magnetic field determined by the steering coil 47 and the permanent magnet 55 in the auxiliary anode 52. The material rod 53 of the hearth 51 is heated by the current from the plasma beam PB, the tip of the material rod 53 is sublimated, and the vapor of the film material is stably emitted therefrom. This vapor is ionized by the plasma beam PB and adheres to, for example, the surface of the substrate to which a negative voltage is applied to form a film.
[0035]
In the film forming apparatus, since the inner layer 251c made of stainless steel is provided inside the guide member 251 for guiding the material rod 53, the inner layer 251c is heated when the material rod 53 is heated by the plasma beam PB during film formation. Limits heat dissipation to some extent. As a result, the material rod 53 is maintained relatively uniformly and at a high temperature and consumed relatively evenly, and the upper surface 53a of the material rod 53 becomes relatively flat, and uniform and stable film formation is possible. At this time, since the material rod 53 does not easily adhere to the stainless inner layer 251c, the material rod 53 can be supplied smoothly. Further, the lines of magnetic force are attracted to the stainless steel inner layer 251c near the tip of the guide member 251, and the plasma beam PB is expanded just above the tip of the guide member 251, so that the upper surface 53a of the material rod 53 is heated relatively uniformly. In addition, more stable film formation becomes possible.
[0036]
[Second Embodiment]
FIG. 4 is a diagram for explaining a main part of the film forming apparatus according to the second embodiment. The film forming apparatus according to the second embodiment is a modification of the film forming apparatus according to the first embodiment, and the same portions are denoted by the same reference numerals and redundant description is omitted.
[0037]
In this case, the hearth 51 includes an annular magnetic member 651 made of a magnetic material on the outer periphery of the upper portion of the guide member 551 fixed on the base member 151. The former guide member 551 is made of copper and is electrically and mechanically connected to the base member 151 to be maintained at an appropriate potential and temperature. The latter magnetic member 651 is made of stainless steel and attracts the magnetic field lines near the tip of the guide member 551. Therefore, the magnetic flux density decreases just above the tip of the guide member 251 and the plasma beam PB is expanded. As a result, the upper surface 53a of the material rod 53 is heated relatively uniformly, and stable film formation becomes possible.
[0038]
As described above, the present invention has been described according to the embodiment, but the present invention is not limited to the above embodiment. For example, when the film is formed using an oxide such as SiO ₂ or MgO as another film material, the material rod 53 can be adhered by providing the inner layer 251c made of stainless steel inside the guide member 251. Thus, the upper surface 53a of the material rod 53 can be made flat, and uniform and stable film formation is possible.
[0039]
Also, the thickness of the inner layer 251c and the shape and arrangement of the magnetic member 651 can be changed as appropriate.
[0040]
Further, the material of the inner layer 251c is not necessarily limited to a magnetic material such as SUS430, and may be another material having no magnetism (for example, SUS304). Furthermore, the material of the magnetic member 651 is not limited to stainless steel, and may be other materials such as iron.
[0041]
【The invention's effect】
As is apparent from the above description, according to the film forming apparatus of the present invention, the guide member is formed of the outer body layer and the inner layer formed of a material that is relatively less reactive with the film material than the body layer. Therefore, it is possible to maintain the cooling capacity, conductivity, and the like of the entire guide member while preventing the film material from adhering to the inside of the guide member during film formation.
[0042]
Further, according to another film forming apparatus of the present invention, since the inner layer is formed of a material having a relatively lower thermal conductivity than that of the main body layer, heat radiation from the film material to the guide member is relatively moderate. As a result, the temperature of the film material can be maintained at a relatively uniform temperature. Therefore, for example, a rod-shaped film material can be dug at a relatively uniform depth, and uniform, stable and rapid film formation becomes possible.
[0043]
According to still another film forming apparatus of the present invention, since the magnetic member made of a magnetic material is provided on the upper outer periphery of the guide member, the magnetic lines of force are attracted to the magnetic member surrounding the guide member in the vicinity of the tip of the guide member. The plasma beam is spread relatively uniformly just above the tip of the guide member. As a result, the upper surface of the film material is heated relatively uniformly, the upper part of the film material is evenly consumed, and stable film formation becomes possible.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating the overall structure of a film forming apparatus according to a first embodiment.
FIG. 2 is a side cross-sectional view illustrating the structure of a hearth incorporated in the film forming apparatus of FIG.
FIG. 3 is a diagram conceptually illustrating the distribution of magnetic lines of force in the vicinity of the tip of the guide member.
FIG. 4 is a side sectional view for explaining the structure of a hearth incorporated in a film forming apparatus according to a second embodiment.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Vacuum vessel 30 Plasma gun 31 Cathode 47 Steering coil 50 Anode member 51 Hearth 52 Auxiliary anode 53 Material rod 55 Permanent magnet 56 Coil 60 Conveying mechanism 62 Roller 90 Carrier gas source 251 Guide member 251b Main body layer 251c Inner layer 651 Magnetic member WH Substrate Holding member

Claims (6)

A plasma source for supplying a plasma beam into the film forming chamber; a hearth disposed in the film forming chamber for guiding the plasma beam; and a material supply device for continuously supplying a film material to the hearth as a material evaporation source. A film forming apparatus comprising:
The hearth is provided with a base member comprising a cavity for cooling, and an annular guide member having an opening through which said membrane material is fixed to the base member, the guide member includes an outer body layer, And an inner layer formed of a material that is relatively less reactive with the film material than the main body layer. A plasma source for supplying a plasma beam into the film forming chamber; a hearth disposed in the film forming chamber for guiding the plasma beam; and a material supply device for continuously supplying a film material to the hearth as a material evaporation source. A film forming apparatus comprising:
The hearth is provided with a base member comprising a cavity for cooling, and an annular guide member having an opening through which said membrane material is fixed to the base member, the guide member includes an outer body layer, And an inner layer formed of a material having a relatively lower thermal conductivity than the main body layer.   The film forming apparatus according to claim 2, wherein the inner layer is formed of a material having a relatively high heat resistant temperature than the main body layer.   The film forming apparatus according to claim 1, wherein the main body layer is made of copper, and the inner layer is made of stainless steel.   5. The film forming apparatus according to claim 1, wherein the inner layer is formed on the guide member side in a through-hole penetrating the base member and the guide member. A plasma source for supplying a plasma beam into the film forming chamber; a hearth disposed in the film forming chamber for guiding the plasma beam; and a material supply device for continuously supplying a film material to the hearth as a material evaporation source. A film forming apparatus comprising:
The hearth includes a ring-shaped guide member having a through-hole through which the film material passes, and a magnetic member made of a magnetic material provided on the outer periphery of the guide member.

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